Sample records for intensity frontier cosmic

  1. Accelerators for Intensity Frontier Research

    SciTech Connect (OSTI)

    Derwent, Paul; /Fermilab

    2012-05-11T23:59:59.000Z

    In 2008, the Particle Physics Project Prioritization Panel identified three frontiers for research in high energy physics, the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. In this paper, I will describe how Fermilab is configuring and upgrading the accelerator complex, prior to the development of Project X, in support of the Intensity Frontier.

  2. Intensity Frontier Instrumentation

    SciTech Connect (OSTI)

    Kettell S.; Rameika, R.; Tshirhart, B.

    2013-09-24T23:59:59.000Z

    The fundamental origin of flavor in the Standard Model (SM) remains a mystery. Despite the roughly eighty years since Rabi asked “Who ordered that?” upon learning of the discovery of the muon, we have not understood the reason that there are three generations or, more recently, why the quark and neutrino mixing matrices and masses are so different. The solution to the flavor problem would give profound insights into physics beyond the Standard Model (BSM) and tell us about the couplings and the mass scale at which the next level of insight can be found. The SM fails to explain all observed phenomena: new interactions and yet unseen particles must exist. They may manifest themselves by causing SM reactions to differ from often very precise predictions. The Intensity Frontier (1) explores these fundamental questions by searching for new physics in extremely rare processes or those forbidden in the SM. This often requires massive and/or extremely finely tuned detectors.

  3. Frontiers in Cosmic Rays

    E-Print Network [OSTI]

    Luis A. Anchordoqui; Charles D. Dermer; Andreas Ringwald

    2004-02-27T23:59:59.000Z

    This rapporteur review covers selected results presented in the Parallel Session HEA2 (High Energy Astrophysics 2) of the 10th Marcel Grossmann Meeting on General Relativity, held in Rio de Janeiro, Brazil, July 2003. The subtopics are: ultra high energy cosmic ray anisotropies, the possible connection of these energetic particles with powerful gamma ray bursts, and new exciting scenarios with a strong neutrino-nucleon interaction in the atmosphere.

  4. Fundamental Physics at the Intensity Frontier

    E-Print Network [OSTI]

    J. L. Hewett; H. Weerts; R. Brock; J. N. Butler; B. C. K. Casey; J. Collar; A. de Gouvea; R. Essig; Y. Grossman; W. Haxton; J. A. Jaros; C. K. Jung; Z. T. Lu; K. Pitts; Z. Ligeti; J. R. Patterson; M. Ramsey-Musolf; J. L. Ritchie; A. Roodman; K. Scholberg; C. E. M. Wagner; G. P. Zeller; S. Aefsky; A. Afanasev; K. Agashe; C. Albright; J. Alonso; C. Ankenbrandt; M. Aoki; C. A. Arguelles; N. Arkani-Hamed; J. R. Armendariz; C. Armendariz-Picon; E. Arrieta Diaz; J. Asaadi; D. M. Asner; K. S. Babu; K. Bailey; O. Baker; B. Balantekin; B. Baller; M. Bass; B. Batell; J. Beacham; J. Behr; N. Berger; M. Bergevin; E. Berman; R. Bernstein; A. J. Bevan; M. Bishai; M. Blanke; S. Blessing; A. Blondel; T. Blum; G. Bock; A. Bodek; G. Bonvicini; F. Bossi; J. Boyce; R. Breedon; M. Breidenbach; S. J. Brice; R. A. Briere; S. Brodsky; C. Bromberg; A. Bross; T. E. Browder; D. A. Bryman; M. Buckley; R. Burnstein; E. Caden; P. Campana; R. Carlini; G. Carosi; C. Castromonte; R. Cenci; I. Chakaberia; M. C. Chen; C. H. Cheng; B. Choudhary; N. H. Christ; E. Christensen; M. E. Christy; T. E. Chupp; E. Church; D. B. Cline; T. E. Coan; P. Coloma; J. Comfort; L. Coney; J. Cooper; R. J. Cooper; R. Cowan; D. F. Cowen; D. Cronin-Hennessy; A. Datta; G. S. Davies; M. Demarteau; D. P. DeMille; A. Denig; R. Dermisek; A. Deshpande; M. S. Dewey; R. Dharmapalan; J. Dhooghe; M. R. Dietrich; M. Diwan; Z. Djurcic; S. Dobbs; M. Duraisamy; B. Dutta; H. Duyang; D. A. Dwyer; M. Eads; B. Echenard; S. R. Elliott; C. Escobar; J. Fajans; S. Farooq; C. Faroughy; J. E. Fast; B. Feinberg; J. Felde; G. Feldman; P. Fierlinger; P. Fileviez Perez; B. Filippone; P. Fisher; B. T. Flemming; K. T. Flood; R. Forty; M. J. Frank; A. Freyberger; A. Friedland; R. Gandhi; K. S. Ganezer; A. Garcia; F. G. Garcia; S. Gardner; L. Garrison; A. Gasparian; S. Geer; V. M. Gehman; T. Gershon; M. Gilchriese; C. Ginsberg; I. Gogoladze; M. Gonderinger; M. Goodman; H. Gould; M. Graham; P. W. Graham; R. Gran; J. Grange; G. Gratta; J. P. Green; H. Greenlee; R. C. Group; E. Guardincerri; V. Gudkov; R. Guenette; A. Haas; A. Hahn; T. Han; T. Handler; J. C. Hardy; R. Harnik; D. A. Harris; F. A. Harris; P. G. Harris; J. Hartnett; B. He; B. R. Heckel; K. M. Heeger; S. Henderson; D. Hertzog; R. Hill; E. A Hinds; D. G. Hitlin; R. J. Holt; N. Holtkamp; G. Horton-Smith; P. Huber; W. Huelsnitz; J. Imber; I. Irastorza; J. Jaeckel; I. Jaegle; C. James; A. Jawahery; D. Jensen; C. P. Jessop; B. Jones; H. Jostlein; T. Junk; A. L. Kagan; M. Kalita; Y. Kamyshkov; D. M. Kaplan; G. Karagiorgi; A. Karle; T. Katori; B. Kayser; R. Kephart; S. Kettell; Y. K. Kim; M. Kirby; K. Kirch; J. Klein; J. Kneller; A. Kobach; M. Kohl; J. Kopp; M. Kordosky; W. Korsch; I. Kourbanis; A. D. Krisch; P. Krizan; A. S. Kronfeld; S. Kulkarni; K. S. Kumar; Y. Kuno; T. Kutter; T. Lachenmaier; M. Lamm; J. Lancaster; M. Lancaster; C. Lane; K. Lang; P. Langacker; S. Lazarevic; T. Le; K. Lee; K. T. Lesko; Y. Li; M. Lindgren; A. Lindner; J. Link; D. Lissauer; L. S. Littenberg; B. Littlejohn; C. Y. Liu; W. Loinaz; W. Lorenzon; W. C. Louis; J. Lozier; L. Ludovici; L. Lueking; C. Lunardini; D. B. MacFarlane; P. A. N. Machado; P. B. Mackenzie; J. Maloney; W. J. Marciano; W. Marsh; M. Marshak; J. W. Martin; C. Mauger; K. S. McFarland; C. McGrew; G. McLaughlin; D. McKeen; R. McKeown; B. T. Meadows; R. Mehdiyev; D. Melconian; H. Merkel; M. Messier; J. P. Miller; G. Mills; U. K. Minamisono; S. R. Mishra; I. Mocioiu; S. Moed Sher; R. N. Mohapatra; B. Monreal; C. D. Moore; J. G. Morfin; J. Mousseau; L. A. Moustakas; G. Mueller; P. Mueller; M. Muether; H. P. Mumm; C. Munger; H. Murayama; P. Nath; O. Naviliat-Cuncin; J. K. Nelson; D. Neuffer; J. S. Nico; A. Norman; D. Nygren; Y. Obayashi; T. P. O'Connor; Y. Okada; J. Olsen; L. Orozco; J. L. Orrell; J. Osta; B. Pahlka; J. Paley; V. Papadimitriou; M. Papucci; S. Parke; R. H. Parker; Z. Parsa; K. Partyka; A. Patch; J. C. Pati; R. B. Patterson; Z. Pavlovic; G. Paz; G. N. Perdue; D. Perevalov; G. Perez; R. Petti; W. Pettus; A. Piepke; M. Pivovaroff; R. Plunkett; C. C. Polly; M. Pospelov; R. Povey; A. Prakesh; M. V. Purohit; S. Raby; J. L. Raaf; R. Rajendran; S. Rajendran; G. Rameika; R. Ramsey; A. Rashed; B. N. Ratcliff; B. Rebel; J. Redondo; P. Reimer; D. Reitzner; F. Ringer; A. Ringwald; S. Riordan; B. L. Roberts; D. A. Roberts; R. Robertson; F. Robicheaux; M. Rominsky; R. Roser; J. L. Rosner; C. Rott; P. Rubin; N. Saito; M. Sanchez; S. Sarkar; H. Schellman; B. Schmidt; M. Schmitt; D. W. Schmitz; J. Schneps; A. Schopper; P. Schuster; A. J. Schwartz; M. Schwarz; J. Seeman; Y. K. Semertzidis; K. K. Seth; Q. Shafi; P. Shanahan; R. Sharma; S. R. Sharpe; M. Shiozawa; V. Shiltsev; K. Sigurdson; P. Sikivie; J. Singh; D. Sivers; T. Skwarnicki; N. Smith; J. Sobczyk; H. Sobel; M. Soderberg; Y. H. Song; A. Soni; P. Souder; A. Sousa; J. Spitz; M. Stancari; G. C. Stavenga; J. H. Steffen

    2012-05-11T23:59:59.000Z

    The Proceedings of the 2011 workshop on Fundamental Physics at the Intensity Frontier. Science opportunities at the intensity frontier are identified and described in the areas of heavy quarks, charged leptons, neutrinos, proton decay, new light weakly-coupled particles, and nucleons, nuclei, and atoms.

  5. Fundamental Physics at the Intensity Frontier

    E-Print Network [OSTI]

    Hewett, J L; Brock, R; Butler, J N; Casey, B C K; Collar, J; de Gouvea, A; Essig, R; Grossman, Y; Haxton, W; Jaros, J A; Jung, C K; Lu, Z T; Pitts, K; Ligeti, Z; Patterson, J R; Ramsey-Musolf, M; Ritchie, J L; Roodman, A; Scholberg, K; Wagner, C E M; Zeller, G P; Aefsky, S; Afanasev, A; Agashe, K; Albright, C; Alonso, J; Ankenbrandt, C; Aoki, M; Arguelles, C A; Arkani-Hamed, N; Armendariz, J R; Armendariz-Picon, C; Diaz, E Arrieta; Asaadi, J; Asner, D M; Babu, K S; Bailey, K; Baker, O; Balantekin, B; Baller, B; Bass, M; Batell, B; Beacham, J; Behr, J; Berger, N; Bergevin, M; Berman, E; Bernstein, R; Bevan, A J; Bishai, M; Blanke, M; Blessing, S; Blondel, A; Blum, T; Bock, G; Bodek, A; Bonvicini, G; Bossi, F; Boyce, J; Breedon, R; Breidenbach, M; Brice, S J; Briere, R A; Brodsky, S; Bromberg, C; Bross, A; Browder, T E; Bryman, D A; Buckley, M; Burnstein, R; Caden, E; Campana, P; Carlini, R; Carosi, G; Castromonte, C; Cenci, R; Chakaberia, I; Chen, M C; Cheng, C H; Choudhary, B; Christ, N H; Christensen, E; Christy, M E; Chupp, T E; Church, E; Cline, D B; Coan, T E; Coloma, P; Comfort, J; Coney, L; Cooper, J; Cooper, R J; Cowan, R; Cowen, D F; Cronin-Hennessy, D; Datta, A; Davies, G S; Demarteau, M; DeMille, D P; Denig, A; Dermisek, R; Deshpande, A; Dewey, M S; Dharmapalan, R; Dhooghe, J; Dietrich, M R; Diwan, M; Djurcic, Z; Dobbs, S; Duraisamy, M; Dutta, B; Duyang, H; Dwyer, D A; Eads, M; Echenard, B; Elliott, S R; Escobar, C; Fajans, J; Farooq, S; Faroughy, C; Fast, J E; Feinberg, B; Felde, J; Feldman, G; Fierlinger, P; Perez, P Fileviez; Filippone, B; Fisher, P; Flemming, B T; Flood, K T; Forty, R; Frank, M J; Freyberger, A; Friedland, A; Gandhi, R; Ganezer, K S; Garcia, A; Garcia, F G; Gardner, S; Garrison, L; Gasparian, A; Geer, S; Gehman, V M; Gershon, T; Gilchriese, M; Ginsberg, C; Gogoladze, I; Gonderinger, M; Goodman, M; Gould, H; Graham, M; Graham, P W; Gran, R; Grange, J; Gratta, G; Green, J P; Greenlee, H; Guardincerri, E; Gudkov, V; Guenette, R; Haas, A; Hahn, A; Han, T; Handler, T; Hardy, J C; Harnik, R; Harris, D A; Harris, F A; Harris, P G; Hartnett, J; He, B; Heckel, B R; Heeger, K M; Henderson, S; Hertzog, D; Hill, R; Hinds, E A; Hitlin, D G; Holt, R J; Holtkamp, N; Horton-Smith, G; Huber, P; Huelsnitz, W; Imber, J; Irastorza, I; Jaeckel, J; Jaegle, I; James, C; Jawahery, A; Jensen, D; Jessop, C P; Jones, B; Jostlein, H; Junk, T; Kagan, A L; Kalita, M; Kamyshkov, Y; Kaplan, D M; Karagiorgi, G; Karle, A; Katori, T; Kayser, B; Kephart, R; Kettell, S; Kim, Y K; Kirby, M; Kirch, K; Klein, J; Kneller, J; Kobach, A; Kohl, M; Kopp, J; Kordosky, M; Korsch, W; Kourbanis, I; Krisch, A D; Krizan, P; Kronfeld, A S; Kulkarni, S; Kumar, K S; Kuno, Y; Kutter, T; Lachenmaier, T; Lamm, M; Lancaster, J; Lancaster, M; Lane, C; Lang, K; Langacker, P; Lazarevic, S; Le, T; Lee, K; Lesko, K T; Li, Y; Lindgren, M; Lindner, A; Link, J; Lissauer, D; Littenberg, L S; Littlejohn, B; Liu, C Y; Loinaz, W; Lorenzon, W; Louis, W C; Lozier, J; Ludovici, L; Lueking, L; Lunardini, C; MacFarlane, D B; Machado, P A N; Mackenzie, P B; Maloney, J; Marciano, W J; Marsh, W; Marshak, M; Martin, J W; Mauger, C; McFarland, K S; McGrew, C; McLaughlin, G; McKeen, D; McKeown, R; Meadows, B T; Mehdiyev, R; Melconian, D; Merkel, H; Messier, M; Miller, J P; Mills, G; Minamisono, U K; Mishra, S R; Mocioiu, I; Sher, S Moed; Mohapatra, R N; Monreal, B; Moore, C D; Morfin, J G; Mousseau, J; Moustakas, L A; Mueller, G; Mueller, P; Muether, M; Mumm, H P; Munger, C; Murayama, H; Nath, P; Naviliat-Cuncin, O; Nelson, J K; Neuffer, D; Nico, J S; Norman, A; Nygren, D; Obayashi, Y; O'Connor, T P; Okada, Y; Olsen, J; Orozco, L; Orrell, J L; Osta, J; Pahlka, B; Paley, J; Papadimitriou, V; Papucci, M; Parke, S; Parker, R H; Parsa, Z; Partyka, K; Patch, A; Pati, J C; Patterson, R B; Pavlovic, Z; Paz, G; Perdue, G N; Perevalov, D; Perez, G; Petti, R; Pettus, W; Piepke, A; Pivovaroff, M; Plunkett, R; Polly, C C; Pospelov, M; Povey, R; Prakesh, A; Purohit, M V; Raby, S; Raaf, J L; Rajendran, R; Rajendran, S; Rameika, G; Ramsey, R; Rashed, A; Ratcliff, B N; Rebel, B; Redondo, J; Reimer, P; Reitzner, D; Ringer, F; Ringwald, A; Riordan, S; Roberts, B L; Roberts, D A; Robertson, R; Robicheaux, F; Rominsky, M; Roser, R; Rosner, J L; Rott, C; Rubin, P; Saito, N; Sanchez, M; Sarkar, S; Schellman, H; Schmidt, B; Schmitt, M; Schmitz, D W; Schneps, J; Schopper, A; Schuster, P; Schwartz, A J; Schwarz, M; Seeman, J; Semertzidis, Y K; Seth, K K; Shafi, Q; Shanahan, P; Sharma, R; Sharpe, S R; Shiozawa, M; Shiltsev, V; Sigurdson, K; Sikivie, P; Singh, J; Sivers, D; Skwarnicki, T; Smith, N; Sobczyk, J; Sobel, H; Soderberg, M; Song, Y H; Soni, A; Souder, P; Sousa, A; Spitz, J; Stancari, M; Stavenga, G C; Steffen, J H; Stepanyan, S; Stoeckinger, D; Stone, S; Strait, J; Strassler, M; Sulai, I A; Sundrum, R; Svoboda, R; Szczerbinska, B; Szelc, A; Takeuchi, T; Tanedo, P

    2012-01-01T23:59:59.000Z

    The Proceedings of the 2011 workshop on Fundamental Physics at the Intensity Frontier. Science opportunities at the intensity frontier are identified and described in the areas of heavy quarks, charged leptons, neutrinos, proton decay, new light weakly-coupled particles, and nucleons, nuclei, and atoms.

  6. Fermilab | Science at Fermilab | Experiments & Projects | Cosmic Frontier

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13, 2013Focusreceives .1Grid Intensity Frontier

  7. Working Group Report: Computing for the Intensity Frontier

    SciTech Connect (OSTI)

    Rebel, B.; Sanchez, M.C.; Wolbers, S.

    2013-10-25T23:59:59.000Z

    This is the report of the Computing Frontier working group on Lattice Field Theory prepared for the proceedings of the 2013 Community Summer Study ("Snowmass"). We present the future computing needs and plans of the U.S. lattice gauge theory community and argue that continued support of the U.S. (and worldwide) lattice-QCD effort is essential to fully capitalize on the enormous investment in the high-energy physics experimental program. We first summarize the dramatic progress of numerical lattice-QCD simulations in the past decade, with some emphasis on calculations carried out under the auspices of the U.S. Lattice-QCD Collaboration, and describe a broad program of lattice-QCD calculations that will be relevant for future experiments at the intensity and energy frontiers. We then present details of the computational hardware and software resources needed to undertake these calculations.

  8. Issues and R&D Required for the Intensity Frontier Accelerators

    SciTech Connect (OSTI)

    Shiltsev, V.; Henderson, S.; Hurh, P.; Kourbanis, I.; Lebedev, V.

    2013-09-26T23:59:59.000Z

    Operation, upgrade and development of accelerators for Intensity Frontier face formidable challenges in order to satisfy both the near-term and long-term Particle Physics program. Here we discuss key issues and R&D required for the Intensity Frontier accelerators.

  9. Fundamental physics at the intensity frontier. Report of the workshop held December 2011 in Rockville, MD.

    SciTech Connect (OSTI)

    Hewett, J.L.; Weerts, H.; Brock, R.; Butler, J.N.; Casey, B.C.K.; Lu, Z.T.; Wagner, C.E.M.; Dietrich, M.R.; Djurcic, Z.; Goodman, M.; Green, J.P.; Holt, R.J.; Mueller, P.; Paley, J.; Reimer, P.; Singh, J.; Upadhye, A. (High Energy Physics); ( PHY); (Stanford Linear Accelerator Center); (Univ. of Michigan); (Fermi National Accelerator Laboratory)

    2012-06-05T23:59:59.000Z

    Particle physics aims to understand the universe around us. The Standard Model of particle physics describes the basic structure of matter and forces, to the extent we have been able to probe thus far. However, it leaves some big questions unanswered. Some are within the Standard Model itself, such as why there are so many fundamental particles and why they have different masses. In other cases, the Standard Model simply fails to explain some phenomena, such as the observed matter-antimatter asymmetry in the universe, the existence of dark matter and dark energy, and the mechanism that reconciles gravity with quantum mechanics. These gaps lead us to conclude that the universe must contain new and unexplored elements of Nature. Most of particle and nuclear physics is directed towards discovering and understanding these new laws of physics. These questions are best pursued with a variety of approaches, rather than with a single experiment or technique. Particle physics uses three basic approaches, often characterized as exploration along the cosmic, energy, and intensity frontiers. Each employs different tools and techniques, but they ultimately address the same fundamental questions. This allows a multi-pronged approach where attacking basic questions from different angles furthers knowledge and provides deeper answers, so that the whole is more than a sum of the parts. A coherent picture or underlying theoretical model can more easily emerge, to be proven correct or not. The intensity frontier explores fundamental physics with intense sources and ultra-sensitive, sometimes massive detectors. It encompasses searches for extremely rare processes and for tiny deviations from Standard Model expectations. Intensity frontier experiments use precision measurements to probe quantum effects. They typically investigate very large energy scales, even higher than the kinematic reach of high energy particle accelerators. The science addresses basic questions, such as: Are there new sources of CP violation? Is there CP violation in the leptonic sector? Are neutrinos their own antiparticles? Do the forces unify? Is there a weakly coupled hidden sector that is related to dark matter? Do new symmetries exist at very high energy scales? To identify the most compelling science opportunities in this area, the workshop Fundamental Physics at the Intensity Frontier was held in December 2011, sponsored by the Office of High Energy Physics in the US Department of Energy Office of Science. Participants investigated the most promising experiments to exploit these opportunities and described the knowledge that can be gained from such a program. The workshop generated much interest in the community, as witnessed by the large and energetic participation by a broad spectrum of scientists. This document chronicles the activities of the workshop, with contributions by more than 450 authors. The workshop organized the intensity frontier science program along six topics that formed the basis for working groups: experiments that probe (i) heavy quarks, (ii) charged leptons, (iii) neutrinos, (iv) proton decay, (v) light, weakly interacting particles, and (vi) nucleons, nuclei, and atoms. The conveners for each working group included an experimenter and a theorist working in the field and an observer from the community at large. The working groups began their efforts well in advance of the workshop, holding regular meetings and soliciting written contributions. Specific avenues of exploration were identified by each working group. Experiments that study rare strange, charm, and bottom meson decays provide a broad program of measurements that are sensitive to new interactions. Charged leptons, particularly muons and taus, provide a precise probe for new physics because the Standard Model predictions for their properties are very accurate. Research at the intensity frontier can reveal CP violation in the lepton sector, and elucidate whether neutrinos are their own antiparticles. A very weakly coupled hidden-sector that may comprise the dark matter in the univ

  10. MARS15 Code Developments Driven by the Intensity Frontier Needs

    E-Print Network [OSTI]

    Mokhov, N V; Rakhno, I L; Striganov, S I; Tropin, I S; Eidelman, Yu I; Aarnio, P; Gudima, K K; Konobeev, A Yu

    2014-01-01T23:59:59.000Z

    The MARS15(2012) is the latest version of a multi-purpose Monte-Carlo code developed since 1974 for detailed simulation of hadronic and electromagnetic cascades in an arbitrary 3-D geometry of shielding, accelerator, detector and spacecraft components with energy ranging from a fraction of an electronvolt to 100 TeV. Driven by needs of the intensity frontier projects with their Megawatt beams, e.g., ESS, FAIR and Project X, the code has been recently substantially improved and extended. These include inclusive and exclusive particle event generators in the 0.7 to 12 GeV energy range, proton inelastic interaction modeling below 20 MeV, implementation of the EGS5 code for electromagnetic shower simulation at energies from 1 keV to 20 MeV, stopping power description in compound materials, new module for DPA calculations for neutrons from a fraction of eV to 20-150 MeV, user-friendly DeTra-based method to calculate nuclide inventories, and new ROOT-based geometry.

  11. Spectral Intensities of Antiprotons and the lifetime of Cosmic Rays in the Galaxy

    E-Print Network [OSTI]

    Cowsik, Ramanath

    2015-01-01T23:59:59.000Z

    In this paper we note that the spectral intensities of antiprotons observed in Galactic cosmic rays in the energy range ~ 1-100 GeV by BESS, PAMELA and AMS instruments display nearly the same spectral shape as that generated by primary cosmic rays through their interaction with matter in the interstellar medium, without any significant modifications. More importantly, a constant residence time of ~ 2.5 +/-0.7 million years in the Galactic volume, independent of the energy of cosmic rays, matches the observed intensities. A small additional component of secondary antiprotons in the energy below 10 GeV, generated in cocoon-like regions surrounding the cosmic-ray sources, seems to be present. We discuss this result in the context of observations of other secondary components like positrons and Boron, and conclude with general remarks about the origins and propagation of cosmic rays.

  12. RECORD-SETTING COSMIC-RAY INTENSITIES IN 2009 AND 2010

    SciTech Connect (OSTI)

    Mewaldt, R. A.; Davis, A. J.; Leske, R. A.; Stone, E. C.; Cummings, A. C.; Labrador, A. W. [California Institute of Technology, Pasadena, CA 91125 (United States); Lave, K. A.; Binns, W. R.; Israel, M. H. [Washington University, St. Louis, MO 63130 (United States); Wiedenbeck, M. E. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Christian, E. R.; De Nolfo, G. A.; Von Rosenvinge, T. T. [NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2010-11-01T23:59:59.000Z

    We report measurements of record-setting intensities of cosmic-ray nuclei from C to Fe, made with the Cosmic Ray Isotope Spectrometer carried on the Advanced Composition Explorer in orbit about the inner Sun-Earth Lagrangian point. In the energy interval from {approx}70 to {approx}450 MeV nucleon{sup -1}, near the peak in the near-Earth cosmic-ray spectrum, the measured intensities of major species from C to Fe were each 20%-26% greater in late 2009 than in the 1997-1998 minimum and previous solar minima of the space age (1957-1997). The elevated intensities reported here and also at neutron monitor energies were undoubtedly due to several unusual aspects of the solar cycle 23/24 minimum, including record-low interplanetary magnetic field (IMF) intensities, an extended period of reduced IMF turbulence, reduced solar-wind dynamic pressure, and extremely low solar activity during an extended solar minimum. The estimated parallel diffusion coefficient for cosmic-ray transport based on measured solar-wind properties was 44% greater in 2009 than in the 1997-1998 solar-minimum period. In addition, the weaker IMF should result in higher cosmic-ray drift velocities. Cosmic-ray intensity variations at 1 AU are found to lag IMF variations by 2-3 solar rotations, indicating that significant solar modulation occurs inside {approx}20 AU, consistent with earlier galactic cosmic-ray radial-gradient measurements. In 2010, the intensities suddenly decreased to 1997 levels following increases in solar activity and in the inclination of the heliospheric current sheet. We describe the conditions that gave cosmic rays greater access to the inner solar system and discuss some of their implications.

  13. Left-Right Symmetric Models at the High-Intensity Frontier

    E-Print Network [OSTI]

    Castillo-Felisola, Oscar; Helo, Juan C; Kovalenko, Sergey G; Ortiz, Sebastian E

    2015-01-01T23:59:59.000Z

    We study constraints on Left-Right Symmetric models from searches of semileptonic decays of $D$, $D_{s}$, $B$ mesons, mediated by heavy neutrinos $N$ with masses $m_N\\sim $ GeV that go on their mass shell leading to a resonant enhancement of the rates. Using these processes we examine, as a function of $m_N$ and $M_{W_R}$, the physics reach of the recently proposed high-intensity beam dump experiment SHiP, which is expected to produce a large sample of $D_s$ mesons. We compare these results with the corresponding reach of neutrinoless double beta decay experiments, as well as like-sign dilepton searches with displaced vertices at the LHC. We conclude that the SHiP experiment has clear advantages in probing the Left-Right Symmetric models for heavy neutrinos in the GeV mass range.

  14. Intensity-Frontier Antiproton Physics with The Antiproton Annihilation Spectrometer (TAPAS) at Fermilab

    SciTech Connect (OSTI)

    Apollinari, Giorgio; /Fermilab; Asner, David M.; /PNL, Richland; Baldini, Wander; /INFN, Ferrara; Bartoszek, Larry; Broemmelsiek, Daniel R.; Brown, Charles N.; /Fermilab; Chakravorty, Alak; /St. Xavier U., Chicago; Colas, Paul; /Saclay; Derwent, Paul; /Fermilab; Drutskoy, Alexey; /Moscow, ITEP; Fortner, Michael; /Northern Illinois U. /Saclay /Indian Inst. Tech., Hyderabad

    2011-11-01T23:59:59.000Z

    The Fermilab Antiproton Source is the world's most intense source of antimatter. With the Tevatron program now behind us, this unique facility can help make the case for Fermilab's continued accelerator operations. The Antiproton Source can be used for unique, dedicated antimatter studies, including medium-energy {bar p}-annihilation experiments. We propose to assemble a powerful, yet cost-effective, solenoidal magnetic spectrometer for antiproton-annihilation events, and to use it at the Fermilab Antiproton Accumulator to measure the charm production cross section, study rare hyperon decays, search for hyperon CP asymmetry, precisely measure the properties of several charmonium and nearby states, and make the first measurements of the Drell-Yan continuum in medium-energy antiproton annihilation. Should the charm production cross section be as large as some have proposed, we will also be able to measure D{sup 0}-{bar D}{sup 0} mixing with high precision and discover (or sensitively limit) charm CP violation. The observation of charm or hyperon CP violation would be evidence for physics beyond the Standard Model, with possible implications for the origin of the baryon asymmetry of the universe - the question of what happened to all the antimatter that must have been produced in the Big Bang. The experiment will be carried out by an international collaboration and will require some four years of running time. As possibly the sole hadron experiment in progress at Fermilab during that time, it will play an important role in maintaining a broad particle physics program at Fermilab and in the U.S. It will thus help us to continue attracting creative and capable young people into science and technology, and introducing them to the important technologies of accelerators, detectors, and data acquisition and analysis - key roles in society that accelerator-based particle physics has historically played.

  15. On the 27-day Variations of Cosmic Ray Intensity in Recent Solar Minimum 23/24

    E-Print Network [OSTI]

    Modzelewska, R

    2015-01-01T23:59:59.000Z

    We have studied the 27-day variations and their harmonics of the galactic cosmic ray (GCR) intensity, solar wind velocity, and interplanetary magnetic field (IMF) components in the recent prolonged solar minimum 23 24. The time evolution of the quasi-periodicity in these parameters connected with the Suns rotation reveals that their synodic period is stable and is aprox 26-27 days. This means that the changes in the solar wind speed and IMF are related to the Suns near equatorial regions in considering the differential rotation of the Sun. However, the solar wind parameters observed near the Earths orbit provide only the conditions in the limited local vicinity of the equatorial region in the heliosphere (within in latitude). We also demonstrate that the observed period of the GCR intensity connected with the Suns rotation increased up to aprox 33-36 days in 2009. This means that the process driving the 27-day variations of the GCR intensity takes place not only in the limited local surroundings of the equato...

  16. On the relationship of the 27-day variations of the solar wind velocity and galactic cosmic ray intensity in minimum epoch of solar activity

    E-Print Network [OSTI]

    Alania, M V; Wawrzynczak, A

    2015-01-01T23:59:59.000Z

    We study the relationship of the 27-day variation of the galactic cosmic ray intensity with similar changes of the solar wind velocity and the interplanetary magnetic field based on the experimental data for the Bartels rotation period 2379 of 23 November 2007-19 December 2007. We develop a three dimensional (3-D) model of the 27-day variation of galactic cosmic ray intensity based on the heliolongitudinally dependent solar wind velocity. A consistent, divergence-free interplanetary magnetic field is derived by solving Maxwells equations with a heliolongitudinally dependent 27-day variation of the solar wind velocity reproducing in situ observations. We consider two types of 3-D models of the 27-day variation of galactic cosmic ray intensity - (1) with a plane heliospheric neutral sheet, and (2)- with the sector structure of the interplanetary magnetic field. The theoretical calculation shows that the sector structure does not influence significantly on the 27-day variation of galactic cosmic ray intensity as...

  17. A proposal to extend the intensity frontier of nuclear and particle physics to 45 GeV (LAMPF 2)

    SciTech Connect (OSTI)

    Not Available

    1984-12-01T23:59:59.000Z

    It is proposed to construct and operate a high-intensity, medium energy synchrotron addition to the Clinton P. Anderson Meson Physics Facility. The addition is to consist of a 6-GeV, 170-..mu..A booster and a 45-GeV, 34-..mu..A, 3-Hz main synchrotron with 50% duty factor. The physics of strong and electroweak interactions to be studied at the facility is discussed, as well as accelerator design, scope of experimental area facilities, and cost estimates and schedule. (LEW)

  18. Some Frontiers of Accelerator Physics

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01T23:59:59.000Z

    Some Frontiers of Accelerator Physics A.M. Sessler OctoberSOME FRONTIERS OF ACCELERATOR PHYSICS* Andrew M. Sessleris Some Frontiers of Accelerator Physics and it is most

  19. Frontiers of Astrophysics - Workshop Summary

    E-Print Network [OSTI]

    Heino Falcke; Peter L. Biermann

    1997-11-07T23:59:59.000Z

    We summarize recent results presented in the astrophysics session during a conference on ``Frontiers of Contemporary Physics''. We will discuss three main fields (High-Energy Astrophysics, Relativistic Astrophysics, and Cosmology), where Astrophysicists are pushing the limits of our knowledge of the physics of the universe to new frontiers. Since the highlights of early 1997 were the first detection of a redshift and the optical and X-ray afterglows of gamma-ray bursts, as well as the first well-documented flares of TeV-Blazars across a large fraction of the electromagnetic spectrum, we will concentrate on these topics. Other topics covered are black holes and relativistic jets, high-energy cosmic rays, Neutrino-Astronomy, extragalactic magnetic fields, and cosmological models.

  20. Environmental Frontier of Sustainability

    E-Print Network [OSTI]

    Takada, Shoji

    A A Global Environmental Studies Frontier of Sustainability Science Akihisa MORI, Global Environmental Studies Satoshi KONISHI, Institute of Advanced Energy, etc Integrated Research Bld This class is designed for graduate students to acknowledge research frontier of Sustainability Science

  1. Modeling and experimental study of the 27-day variation of galactic cosmic-ray intensity for a solar-wind velocity depending on heliolongitude

    E-Print Network [OSTI]

    Alania, M V; Wawrzynczak, A

    2015-01-01T23:59:59.000Z

    We develop a three dimensional (3-D) model of the 27-day variation of galactic cosmic ray (GCR) intensity with a spatial variation of the solar wind velocity. A consistent, divergence-free interplanetary magnetic field is derived by solving the corresponding Maxwell equations with a variable solar wind speed, which reproduces in situ observed experimental data for the time interval to be analyzed (24 August 2007-28 February 2008). We perform model calculations for the GCR intensity using the variable solar wind and the corresponding magnetic field. Results are compatible with experimental data; the correlation coefficient between our model predictions and observed 27-day GCR variation is 0.80 0.05.

  2. Muon Colliders: The Next Frontier

    ScienceCinema (OSTI)

    Yagmur Tourun

    2010-01-08T23:59:59.000Z

    Muon Colliders provide a path to the energy frontier in particle physics but have been regarded to be "at least 20 years away" for 20 years. I will review recent progress in design studies and hardware R&D and show that a Muon Collider can be established as a real option for the post-LHC era if the current vigorous R&D effort revitalized by the Muon Collider Task Force at Fermilab can be supported to its conclusion. All critical technologies are being addressed and no show-stoppers have emerged. Detector backgrounds have been studied in detail and appear to be manageable and the physics can be done with existing detector technology. A muon facility can be built through a staged scenario starting from a low-energy muon source with unprecedented intensity for exquisite reach for rare processes, followed by a Neutrino Factory with ultrapure neutrino beams with unparalleled sensitivity for disentangling neutrino mixing, leading to an energy frontier Muon Collider with excellent energy resolution.

  3. Connecting Accelerator RD to User Needs | U.S. DOE Office of...

    Office of Science (SC) Website

    High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier Cosmic Frontier Theoretical Physics Advanced Technology...

  4. Environmental Frontier of Sustainability Science

    E-Print Network [OSTI]

    Takada, Shoji

    A Global Environmental Studies Frontier of Sustainability Science Akihisa MORI, Global Environmental Studies Satoshi KONISHI, Institute of Advanced Energy, etc Master July 14 frontier of Sustainability Science. Sustainability Science is a new academic field that was lately created

  5. SOLAR CYCLE DEPENDENCE OF THE DIURNAL ANISOTROPY OF 0.6 TeV COSMIC-RAY INTENSITY OBSERVED WITH THE MATSUSHIRO UNDERGROUND MUON DETECTOR

    SciTech Connect (OSTI)

    Munakata, K.; Mizoguchi, Y.; Kato, C.; Yasue, S.; Mori, S. [Department of Physics, Shinshu University, Matsumoto 390-8621 (Japan); Takita, M. [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Kota, J., E-mail: kmuna00@shinshu-u.ac.j [Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 87721 (United States)

    2010-04-01T23:59:59.000Z

    We analyze the temporal variation of the diurnal anisotropy of sub-TeV cosmic-ray intensity observed with the Matsushiro (Japan) underground muon detector over two full solar activity cycles in 1985-2008. We find an anisotropy component in the solar diurnal anisotropy superimposed on the Compton-Getting anisotropy due to Earth's orbital motion around the Sun. The phase of this additional anisotropy is almost constant at {approx}15:00 local solar time corresponding to the direction perpendicular to the average interplanetary magnetic field at Earth's orbit, while the amplitude varies between a maximum (0.043% +- 0.002%) and minimum ({approx}0.008% +- 0.002%) in a clear correlation with the solar activity. We find a significant time lag between the temporal variations of the amplitude and the sunspot number (SSN) and obtain the best correlation coefficient of +0.74 with the SSN delayed for 26 months. We suggest that this anisotropy might be interpreted in terms of the energy change due to the solar-wind-induced electric field expected for galactic cosmic rays (GCRs) crossing the wavy neutral sheet. The average amplitude of the sidereal diurnal variation over the entire period is 0.034% +- 0.003%, which is roughly one-third of the amplitude reported from air shower and deep-underground muon experiments monitoring multi-TeV GCR intensity suggesting a significant attenuation of the anisotropy due to the solar modulation. We find, on the other hand, only a weak positive correlation between the sidereal diurnal anisotropy and the solar activity cycle in which the amplitude in the 'active' solar activity epoch is about twice the amplitude in the 'quiet' solar activity epoch. This implies that only one-fourth of the total attenuation varies in correlation with the solar activity cycle and/or the solar magnetic cycle. We finally examine the temporal variation of the 'single-band valley depth' (SBVD) quoted by the Milagro experiment and, in contrast with recent Milagro's report, we find no steady increase in the Matsushiro observations in a seven-year period between 2000 and 2007. We suggest, therefore, that the steady increase of the SBVD reported by the Milagro experiment is not caused by the decreasing solar modulation in the declining phase of the 23rd solar activity cycle.

  6. A Comparison of Radial Intensity Profiles of Termination Shock Particles and Anomalous Cosmic Rays in the Outer North-South Heliosheaths Using CRS data from V1 and V2

    E-Print Network [OSTI]

    Webber, W R

    2015-01-01T23:59:59.000Z

    Using data from the Voyager 1 and 2 CRS telescopes available on the web through the end of 2014 we have studied the intensity variations of termination shock H nuclei and anomalous cosmic ray H and He nuclei as a function of radial distance. In contrast to the inner part of the heliosheath where the intensity vs. radius profiles in the North and South heliosheaths are much different, these intensity vs. radius profiles, as well as the intensities themselves, are more similar in the outer North and South heliosheaths as measured by V1 and V2 respectively. In the N heliosheath, taken to be 27.6 AU thick beyond the HTS crossing distance of 94 AU, the intensities of termination shock particles and anomalous cosmic rays reach a maximum at between 110-112 AU or at a location ~halfway between the termination shock and the heliopause. They then decrease more or less continuously to an intensity ~2/3 of the maximum for each component just before the final dropout at ~121 AU, just inside the heliopause. This intensity-...

  7. Energy Frontier Research Centers | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Synthesis from Atoms to Systems Materials Characterization Materials Theory and Simulation Energy Frontier Research Centers Center for Defect Physics in Structural...

  8. Frontiers in Science Archive

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA)Budget(DANCE)FrequentlyLectures » Frontiers in Science

  9. Snowmass Energy Frontier Simulations

    E-Print Network [OSTI]

    Jacob Anderson; Aram Avetisyan; Raymond Brock; Sergei Chekanov; Timothy Cohen; Nitish Dhingra; James Dolen; James Hirschauer; Kiel Howe; Ashutosh Kotwal; Tom LeCompte; Sudhir Malik; Patricia Mcbride; Kalanand Mishra; Meenakshi Narain; Jim Olsen; Sanjay Padhi; Michael E. Peskin; John Stupak III; Jay G. Wacker

    2013-09-01T23:59:59.000Z

    This document describes the simulation framework used in the Snowmass Energy Frontier studies for future Hadron Colliders. An overview of event generation with {\\sc Madgraph}5 along with parton shower and hadronization with {\\sc Pythia}6 is followed by a detailed description of pile-up and detector simulation with {\\sc Delphes}3. Details of event generation are included in a companion paper cited within this paper. The input parametrization is chosen to reflect the best object performance expected from the future ATLAS and CMS experiments; this is referred to as the "Combined Snowmass Detector". We perform simulations of $pp$ interactions at center-of-mass energies $\\sqrt{s}=$ 14, 33, and 100 TeV with 0, 50, and 140 additional $pp$ pile-up interactions. The object performance with multi-TeV $pp$ collisions are studied for the first time using large pile-up interactions.

  10. Cosmic Microwave Background Polarization

    E-Print Network [OSTI]

    James G. Bartlett

    2006-04-18T23:59:59.000Z

    Cosmic microwave background (CMB) anisotropy is our richest source of cosmological information; the standard cosmological model was largely established thanks to study of the temperature anisotropies. By the end of the decade, the Planck satellite will close this important chapter and move us deeper into the new frontier of polarization measurements. Numerous ground--based and balloon--borne experiments are already forging into this new territory. Besides providing new and independent information on the primordial density perturbations and cosmological parameters, polarization measurements offer the potential to detect primordial gravity waves, constrain dark energy and measure the neutrino mass scale. A vigorous experimental program is underway worldwide and heading towards a new satellite mission dedicated to CMB polarization.

  11. Cosmic Microwave Background Project at NERSC

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi Site Office (FSO)CorporateCosmic Frontier HighCosmic

  12. Proceedings of ICRC 2001: 3838 c Copernicus Gesellschaft 2001 Long-term cosmic ray intensity vs. solar proxies: A simple linear

    E-Print Network [OSTI]

    Usoskin, Ilya G.

    intensity vs. solar proxies: A simple linear relation does not work K. Mursula1 , I. G. Usoskin2 , and G. A. Kovaltsov3 1 Department of Physical Sciences, FIN-90014 University of Oulu, Finland 2 Sodankyl¨a Geophysical Observatory (Oulu unit), FIN-90014 University of Oulu, Finland 3 Ioffe Physical-Technical Institute, St

  13. Cosmic Frontier | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,,of Science (SC)ContractContractContract

  14. Photo of the Week: The Cosmic Frontier | Department of Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeedingBiomassPPPOPetroleum Reserves Vision,4 Photo of the13,ofThe 2014The

  15. Research Frontiers Cutting-Edge Research

    E-Print Network [OSTI]

    Takada, Shoji

    Research Frontiers Cutting-Edge Research in Kyoto University Kyoto University is known. Some of them exhibit circularly polarized light (CPL) with unprecedented anisotropy factors: they emit

  16. NERSC Frontiers in Advanced Storage Technology Project

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Storage R&D Frontiers in Advanced Storage Technologies (FAST) project Working with vendors to develop new functionality in storage technologies generally not yet available to...

  17. Pushing the Frontier of High-Definition Ion Mobility Spectrometry...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the Frontier of High-Definition Ion Mobility Spectrometry Using FAIMS. Pushing the Frontier of High-Definition Ion Mobility Spectrometry Using FAIMS. Abstract: Differential ion...

  18. Frontiers, Opportunities, and Challenges in Biochemical and Chemical...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Frontiers, Opportunities, and Challenges in Biochemical and Chemical Catalysis of CO2. Frontiers, Opportunities, and Challenges in Biochemical and Chemical Catalysis of CO2....

  19. Los Alamos engineer selected to participate in NAE's 2012 "Frontiers...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Moody to participate in "Frontiers of Engineering" Los Alamos engineer selected to participate in NAE's 2012 "Frontiers of Engineering" symposium Engineers between 30 to 45 who are...

  20. DOE to Award $100 Million for Energy Frontier Research Centers...

    Office of Science (SC) Website

    to Award 100 Million for Energy Frontier Research Centers Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC...

  1. Department of Energy Hosts Inaugural Energy Frontier Research...

    Office of Science (SC) Website

    News & Events DOE Announcements Department of Energy Hosts Inaugural Energy Frontier Research Center Summit Energy Frontier Research Centers (EFRCs) EFRCs Home Centers...

  2. Frontier Associates | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A PotentialJumpGermanFife EnergyFreight Best PracticeFrey| OpenFrontier

  3. Frontiers in Science Lecture Series

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA)Budget(DANCE)FrequentlyLectures » Frontiers in

  4. Intensity Frontier| U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron4 Self-Scrubbing:,,ofOpportunitieshighlights/ Theisc/about/jobs/ Below

  5. Fermilab | For Physicists & Engineers | Fellowships | Intensity Frontier

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13, 2013Focus Group Report Robert R.Fellows

  6. Cosmic Rays and Global Warming

    E-Print Network [OSTI]

    T. Sloan; A W Wolfendale

    2007-06-28T23:59:59.000Z

    It has been claimed by others that observed temporal correlations of terrestrial cloud cover with `the cosmic ray intensity' are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim to look for evidence to corroborate it. So far we have not found any and so our tentative conclusions are to doubt it. Such correlations as appear are more likely to be due to the small variations in solar irradiance, which, of course, correlate with cosmic rays. We estimate that less than 15% of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 35 years is due to this cause.

  7. Frontiers in Chemical Imaging Seminar Series

    E-Print Network [OSTI]

    Frontiers in Chemical Imaging Seminar Series On the trail of the Chimera The Atom the Chimera is still elusive. 1. Thomas F. Kelly and David J. Larson. Ann Rev. Materials Res 42 (2012) 1. 2

  8. Microfluidics Expanding the Frontiers of Microbial Ecology

    E-Print Network [OSTI]

    Rusconi, Roberto

    Microfluidics has significantly contributed to the expansion of the frontiers of microbial ecology over the past decade by allowing researchers to observe the behaviors of microbes in highly controlled microenvironments, ...

  9. Systematic Analysis of Frontier Energy Collider Data

    E-Print Network [OSTI]

    Bruce Knuteson

    2005-04-23T23:59:59.000Z

    Ignorance of the form new physics will take suggests the importance of systematically analyzing all data collected at the energy frontier, with the goal of maximizing the chance for discovery both before and after the turn on of the LHC.

  10. World-making with extended gravity black holes for cosmic natural selection in the multiverse scenario

    E-Print Network [OSTI]

    A. Barrau

    2007-02-09T23:59:59.000Z

    Physics is facing contingency. Not only in facts but also in laws (the frontier becoming extremely narrow). Cosmic natural selection is a tantalizing idea to explain the apparently highly improbable structure of our Universe. In this brief note I will study the creation of Universes by black holes in -string inspired- higher order curvature gravity.

  11. Cosmic Rays and Global Warming

    SciTech Connect (OSTI)

    Sloan, T. [Physics Department, University of Lancaster, Lancaster, UK (United Kingdom); Wolfendale, A. W. [Physics Department, Durham University, Durham (United Kingdom)

    2008-01-24T23:59:59.000Z

    Some workers have claimed that the observed temporal correlations of (low level) terrestrial cloud cover with the cosmic ray intensity changes, due to solar modulation, are causal. The possibility arises, therefore, of a connection between cosmic rays and Global Warming. If true, the implications would be very great. We have examined this claim in some detail. So far, we have not found any evidence in support and so our conclusions are to doubt it. From the absence of corroborative evidence we estimate that less than 15% at the 95% confidence level, of the 11-year cycle warming variations are due to cosmic rays and less than 2% of the warming over the last 43 years is due to this cause. The origin of the correlation itself is probably the cycle of solar irradiance although there is, as yet, no certainty.

  12. Fundamental Physics Explored with High Intensity Laser

    E-Print Network [OSTI]

    T. Tajima; K. Homma

    2012-09-13T23:59:59.000Z

    Over the last Century the method of particle acceleration to high energies has become the prime approach to explore the fundamental nature of matter in laboratory. It appears that the latest search of the contemporary accelerator based on the colliders shows a sign of saturation (or at least a slow-down) in increasing its energy and other necessary parameters to extend this frontier. We suggest two pronged approach enabled by the recent progress in high intensity lasers.

  13. Opening New Frontiers in Power Generation

    E-Print Network [OSTI]

    Haile, Sossina M.

    FUEL CELLS Opening New Frontiers in Power Generation U . S . D e p a r t m e n t o f E n e r g y in the power generation industry. Fuel cells have the potential to truly revolutionize power generation. Fuel by subjecting it to steam and high temperatures. In order to use coal, biomass, or a range of hydrocarbon wastes

  14. Global Emergence of Frontier Knowledge November 2013

    E-Print Network [OSTI]

    Yamamoto, Hirosuke

    , Infrastructure, Medical and Biologi- cal Engineering, Mineral Resources, Nano Physics, SustainabilityGlobal Emergence of Frontier Knowledge November 2013 Nov. 7th U.Católica (Casa Central) 09:00 Doors, Culture & Body, Earthquakes, Tsunami & Volcanoes, Element & Material Sciences, Food Resource

  15. Frontiers in Chemical Imaging Seminar Series

    E-Print Network [OSTI]

    the positions of Professor in the Dept. of Materials Science and Engineering, University of TennesseeFrontiers in Chemical Imaging Seminar Series Presented by Dr. Stephen J Pennycook, Ph.D. Materials properties. Finally, the direct imaging and identification of point defect configurations in monolayer BN

  16. Frontiers in Exploration Workshop Organizing Committee

    E-Print Network [OSTI]

    Sparks, Donald L.

    Mary Firestone, University of California, Berkeley Dan Richter, Duke University Art White, USGS, Menlo., Pregitzer, K., Derry, L., Chorover, J., Chadwick, O., April, R., Anderson, S., Amundson, R., 2006, Frontiers, and in soil chemistry, and can be inferred from histori- cal data and from the geologic re- cord (ANDERSON ET

  17. Frontiers in Global Change Seminar Series

    E-Print Network [OSTI]

    Frontiers in Global Change Seminar Series Aerosol-Cloud Interactions: The Elusive Component particles ("aerosols") exert a net cooling effect by directly scattering and absorption of solar radiation (the "aerosol direct climatic effect"). Aerosols also affect clouds by acting as the seed for droplet

  18. PNNLs Data Intensive Computing research battles Homeland Security threats

    ScienceCinema (OSTI)

    David Thurman; Joe Kielman; Katherine Wolf; David Atkinson

    2012-12-31T23:59:59.000Z

    The Pacific Northwest National Laboratorys (PNNL's) approach to data intensive computing (DIC) is focused on three key research areas: hybrid hardware architecture, software architectures, and analytic algorithms. Advancements in these areas will help to address, and solve, DIC issues associated with capturing, managing, analyzing and understanding, in near real time, data at volumes and rates that push the frontiers of current technologies.

  19. PNNL pushing scientific discovery through data intensive computing breakthroughs

    ScienceCinema (OSTI)

    Deborah Gracio; David Koppenaal; Ruby Leung

    2012-12-31T23:59:59.000Z

    The Pacific Northwest National Laboratorys approach to data intensive computing (DIC) is focused on three key research areas: hybrid hardware architectures, software architectures, and analytic algorithms. Advancements in these areas will help to address, and solve, DIC issues associated with capturing, managing, analyzing and understanding, in near real time, data at volumes and rates that push the frontiers of current technologies.

  20. Apply: Building Energy Efficiency Frontiers and Incubator Technologies...

    Energy Savers [EERE]

    for inclusion in future program roadmaps. Frontiers will support advancing program roadmap-driven R&D activities that contribute to core program technological areas. It is...

  1. How Will We Explore Earth's Final Frontier? | GE Global Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    see how technology is helping us understand, utilize and protect the last frontier on earth. At GE Global Research's Rio de Janiero location, researchers are developing...

  2. Frontiers in Computational and Information Sciences Seminar Series

    E-Print Network [OSTI]

    Frontiers in Computational and Information Sciences Seminar Series Programming Models in the Exascale Era Presented by... Professor Barbara Chapman Department of Computer Science University of Houston

  3. Frontiers in Computational and Information Sciences Seminar Series

    E-Print Network [OSTI]

    Frontiers in Computational and Information Sciences Seminar Series The PhyloFacts Microbial evolutionary reconstruction of gene families, integrating information from protein 3D structure, biological

  4. Links | NEES - EFRC | University of Maryland Energy Frontier...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sciences U.S. Department of Energy, EFRC Program Energy Frontier Community The University of Maryland, College Park Sandia National Laboratories The University of California,...

  5. EFRC management reference document Energy Frontier Research Centers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    appropriate acknowledgment of the facility or equipment and its supporting agency. EFRC management reference document Energy Frontier Research Centers Acknowledgments of Support...

  6. Frontiers in Planetary and Stellar Magnetism through High-Performance...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hwang, project co-PI Frontiers in Planetary and Stellar Magnetism through High-Performance Computing PI Name: Jonathan Aurnou PI Email: aurnou@ucla.edu Institution: University...

  7. 343. Document entitled "Develop "Frontier" Resources to Ensure...

    Broader source: Energy.gov (indexed) [DOE]

    3. Document entitled "Develop "Frontier" Resources to Ensure Future Oil and Natural Gas Supply," dated March 8, 2001. B-5 Exemption - Information withheld (under Exemption 5)...

  8. Life at the Frontiers of Energy Research Video Contest | U.S...

    Office of Science (SC) Website

    Life at the Frontiers of Energy Research Video Contest Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC Events...

  9. Cosmic Reionization On Computers | Argonne Leadership Computing Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi Site Office (FSO)CorporateCosmic Frontier

  10. Interstellar Hydrogen and Cosmic Background Radiation

    E-Print Network [OSTI]

    B. G. Sidharth

    2000-04-18T23:59:59.000Z

    It is shown that a collection of photons with nearly the same frequency exhibits a "condensation" type of phenomenon corresponding to a peak intensity. The observed cosmic background radiation can be explained from this standpoint in terms of the radiation due to fluctuations in interstellar Hydrogen.

  11. Cosmic Background Radiation Due to Photon Condensation

    E-Print Network [OSTI]

    B. G. Sidharth

    1998-06-10T23:59:59.000Z

    It is shown that a collection of photons with nearly the same frequency exhibits a Bose "condensation" type of phenomenon at about 3 degrees K corresponding to a peak intensity at a wave length of about 0.4cm. This could give a mechanism for the observed Cosmic Background Radiation, and also explain some curious features.

  12. USC-CHEVRON FRONTIERS OF ENERGY RESOURCES SUMMER CAMP

    E-Print Network [OSTI]

    Shahabi, Cyrus

    to genuine challenges, such as the estimation of business costs for hypothetical conversion of coal powerUSC-CHEVRON FRONTIERS OF ENERGY RESOURCES SUMMER CAMP CHALLENGES FUTURE ENERGY ENGINEERS the 2013 Frontiers of Energy Resources Summer Camp this past June. The program, sponsored by Chevron

  13. Proximate Population Factors and Deforestation in Tropical Agricultural Frontiers

    E-Print Network [OSTI]

    Lopez-Carr, David

    Proximate Population Factors and Deforestation in Tropical Agricultural Frontiers David L. Carr are significantly associated at the global and regional scales, evidence for population links to deforestation of thought on population­environment theories relevant to deforestation in tropical agricultural frontiers

  14. Quantum Field Theory & Gravity

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Quantum Field Theory & Gravity Quantum Field Theory & Gravity Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664...

  15. Dark Matter Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dark Matter Theory Dark Matter Theory Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten (505)...

  16. Frontier Renewables LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A PotentialJumpGermanFife EnergyFreight Best PracticeFrey|Frontier Renewables

  17. Physics Advisory Committee Meeting November 3-5, 2008

    E-Print Network [OSTI]

    Quigg, Chris

    in the Particle Physics Project Prioritization Panel (P5) report to HEPAP--the Energy Frontier, the Intensity Frontier and the Cosmic Frontier. The current highest priority of the Fermilab program is the Energy Frontier. The Tevatron is the world's highest energy accelerator. Even after this is no longer true

  18. Towards hadronic shower timing with CALICE Analog Hadron Calorimeter, Calorimetry for High Energy Frontier

    E-Print Network [OSTI]

    Ramilli, M

    2015-01-01T23:59:59.000Z

    Towards hadronic shower timing with CALICE Analog Hadron Calorimeter, Calorimetry for High Energy Frontier

  19. Cosmic-ray Muon Flux In Belgrade

    SciTech Connect (OSTI)

    Banjanac, R.; Dragic, A.; Jokovic, D.; Udovicic, V. [Institute of Physics, University of Belgrade, Belgrade (Serbia and Montenegro); Puzovic, J.; Anicin, I. [Faculty of Physics, University of Belgrade, Belgrade (Serbia and Montenegro)

    2007-04-23T23:59:59.000Z

    Two identical plastic scintillator detectors, of prismatic shape (50x23x5)cm similar to NE102, were used for continuous monitoring of cosmic-ray intensity. Muon {delta}E spectra have been taken at five minute intervals, simultaneously from the detector situated on the ground level and from the second one at the depth of 25 m.w.e in the low-level underground laboratory. Sum of all the spectra for the years 2002-2004 has been used to determine the cosmic-ray muon flux at the ground level and in the underground laboratory.

  20. IGNITION AND FRONTIER SCIENCE ON THE NATIONAL IGNITION FACILITY

    SciTech Connect (OSTI)

    Moses, E

    2009-06-22T23:59:59.000Z

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and experiments studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF construction Project was certified by the Department of Energy as complete on March 30, 2009. NIF, a 192-beam Nd-glass laser facility, will produce 1.8 MJ, 500 TW of light at the third-harmonic, ultraviolet light of 351 nm. On March 10, 2009, a total 192-beam energy of 1.1 MJ was demonstrated; this is approximately 30 times more energy than ever produced in an ICF laser system. The principal goal of NIF is to achieve ignition of a deuterium-tritium (DT) fuel capsule and provide access to HED physics regimes needed for experiments related to national security, fusion energy and for broader frontier scientific exploration. NIF experiments in support of indirect drive ignition will begin in FY2009. These first experiments represent the next phase of the National Ignition Campaign (NIC). The NIC is a 1.7 billion dollar national effort to achieve fusion ignition and is coordinated through a detailed execution plan that includes the science, technology, and equipment. Equipment required for ignition experiments include diagnostics, cryogenic target manipulator, and user optics. Participants in this effort include LLNL, General Atomics (GA), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), and the University of Rochester Laboratory for Energetics (LLE). The primary goal for NIC is to have all of the equipment operational and integrated into the facility and be ready to begin a credible ignition campaign in 2010. With NIF now operational, the long-sought goal of achieving self-sustained nuclear fusion and energy gain in the laboratory is much closer to realization. Successful demonstration of ignition and net energy gain on NIF will be a major step towards demonstrating the feasibility of Inertial Fusion Energy (IFE) and will likely focus the world's attention on the possibility of an ICF energy option. NIF experiments to demonstrate ignition and gain will use central-hot-spot (CHS) ignition, where a spherical fuel capsule is simultaneously compressed and ignited. The scientific basis for CHS has been intensively developed and has high probability of success. Achieving ignition with CHS will open the door for other advanced concepts, such as the use of high-yield pulses of visible wavelength rather than ultraviolet and Fast Ignition concepts. Moreover, NIF will have important scientific applications in such diverse fields as astrophysics, nuclear physics and materials science. The NIC will develop the full set of capabilities required to operate NIF as a major national and international user facility. A solicitation for NIF frontier science experiments to be conducted by the academic community is planned for summer 2009. This paper summarizes the design, performance, and status of NIF, experimental plans for NIC, and will present a brief discussion of the unparalleled opportunities to explore frontier basic science that will be available on the NIF.

  1. Origin of Cosmic Radiation

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2000-11-28T23:59:59.000Z

    I give a brief overview of cosmic ray physics, highlighting some key questions and how they will be addressed by new experiments.

  2. Frontiers of in situ electron microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zheng, Haimei; Zhu, Yimei; Meng, Shirley Ying

    2015-01-01T23:59:59.000Z

    In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by inmore »this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.« less

  3. Frontiers of interfacial water research :workshop report.

    SciTech Connect (OSTI)

    Cygan, Randall Timothy; Greathouse, Jeffery A.

    2005-10-01T23:59:59.000Z

    Water is the critical natural resource of the new century. Significant improvements in traditional water treatment processes require novel approaches based on a fundamental understanding of nanoscale and atomic interactions at interfaces between aqueous solution and materials. To better understand these critical issues and to promote an open dialog among leading international experts in water-related specialties, Sandia National Laboratories sponsored a workshop on April 24-26, 2005 in Santa Fe, New Mexico. The ''Frontiers of Interfacial Water Research Workshop'' provided attendees with a critical review of water technologies and emphasized the new advances in surface and interfacial microscopy, spectroscopy, diffraction, and computer simulation needed for the development of new materials for water treatment.

  4. EFRC Overview | University of Texas Energy Frontier Research...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    About the EFRC The Center for Nano- and Molecular Science and Technology (CNM) at The University of Texas at Austin is the site of an Energy Frontier Research Center (EFRC) funded...

  5. Earthquake triggering discussed in three Frontiers in Science...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Frontiers in Science lectures by Paul Johnson of Los Alamos National Laboratory's Geophysics group. The first lecture is at 7 p.m. Nov. 12 at the New Mexico Museum of Natural...

  6. Frontiers in Catalysis Science and Engineering Materials Science

    E-Print Network [OSTI]

    Frontiers in Catalysis Science and Engineering Materials Science Chemical Imaging Date: May 13 the quality of human life but also critical to our survival. To power the planet for a better future

  7. Heart of the Solution - Energy Frontiers (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Green, Peter F. (Director, Center for Solar and Thermal Energy Conversion, University of Michigan); CSTEC Staff

    2011-11-02T23:59:59.000Z

    'Heart of the Solution - Energy Frontiers' was submitted by the Center for Solar and Thermal Energy Conversion (CSTEC) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. This video was both the People's Choice Award winner and selected as one of five winners by a distinguished panel of judges for its 'exemplary explanation of the role of an Energy Frontier Research Center'. The Center for Solar and Thermal Energy Conversion is directed by Peter F. Green at the University of Michigan. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Solar and Thermal Energy Conversion is 'to study complex material structures on the nanoscale to identify key features for their potential use as materials to convert solar energy and heat to electricity.' Research topics are: solar photovoltaic, photonic, optics, solar thermal, thermoelectric, phonons, thermal conductivity, solar electrodes, defects, ultrafast physics, interfacial characterization, matter by design, novel materials synthesis, charge transport, and self-assembly.

  8. Characterization and fluid flow simulation of naturally fractured Frontier sandstone, Green River Basin, Wyoming

    SciTech Connect (OSTI)

    Harstad, H. [New Mexico Tech, Socorro, NM (United States); Teufel, L.W.; Lorenz, J.C.; Brown, S.R. [Sandia National Labs., Albuquerque, NM (United States). Geomechanics Dept.

    1996-08-01T23:59:59.000Z

    Significant gas reserves are present in low-permeability sandstones of the Frontier Formation in the greater Green River Basin, Wyoming. Successful exploitation of these reservoirs requires an understanding of the characteristics and fluid-flow response of the regional natural fracture system that controls reservoir productivity. Fracture characteristics were obtained from outcrop studies of Frontier sandstones at locations in the basin. The fracture data were combined with matrix permeability data to compute an anisotropic horizontal permeability tensor (magnitude and direction) corresponding to an equivalent reservoir system in the subsurface using a computational model developed by Oda (1985). This analysis shows that the maximum and minimum horizontal permeability and flow capacity are controlled by fracture intensity and decrease with increasing bed thickness. However, storage capacity is controlled by matrix porosity and increases linearly with increasing bed thickness. The relationship between bed thickness and the calculated fluid-flow properties was used in a reservoir simulation study of vertical, hydraulically-fractured and horizontal wells and horizontal wells of different lengths in analogous naturally fractured gas reservoirs. The simulation results show that flow capacity dominates early time production, while storage capacity dominates pressure support over time for vertical wells. For horizontal wells drilled perpendicular to the maximum permeability direction a high target production rate can be maintained over a longer time and have higher cumulative production than vertical wells. Longer horizontal wells are required for the same cumulative production with decreasing bed thickness.

  9. On the relationship between cosmic rays, solar activity and powerful earthquakes

    E-Print Network [OSTI]

    Mikhail Kovalyov; Selena Kovalyov

    2015-02-10T23:59:59.000Z

    In this paper we analyze the correlation of cosmic rays intensity to increases in seismic activity. We also show that high-magnitude earthquakes appear in group. As a prequel, we discuss in \\S1 naive visualization of the solar-cosmic ray interplay.

  10. Cosmic rays in astrospheres

    E-Print Network [OSTI]

    Scherer, Klaus; Bomans, Dominik; Ferreira, Stefan; Fichtner, Horst; Kleimann, Jens; Strauss, Dutoit; Weis, Kerstin; Wiengarten, Tobias; Wodzinski, Thomas

    2015-01-01T23:59:59.000Z

    Cosmic rays passing through large astrospheres can be efficiently cooled inside these "cavities" in the interstellar medium. Moreover, the energy spectra of these energetic particles are already modulated in front of the astrospherical bow shocks. We study the cosmic ray flux in and around lambda Cephei as an example for an astrosphere. The large-scale plasma flow is modeled hydrodynamically with radiative cooling. We studied the cosmic ray flux in a stellar wind cavity using a transport model based on stochastic differential equations. The required parameters, most importantly, the elements of the diffusion tensor, are based on the heliospheric parameters. The magnetic field required for the diffusion coefficients is calculated kinematically. We discuss the transport in an astrospheric scenario with varying parameters for the transport coefficients. We show that large stellar wind cavities can act as sinks for the galactic cosmic ray flux and thus can give rise to small-scale anisotropies in the direction to...

  11. The Cosmic Background Radiation

    E-Print Network [OSTI]

    George Smoot; Douglas Scott

    1997-11-08T23:59:59.000Z

    We summarise the current status of cosmic microwave background spectrum and anisotropy measurements, and their theoretical interpretation. This is the update of the mini-review for the 1997 web-version of the Review of Particle Properties.

  12. US Residential Energy Demand and Energy Efficiency: A Stochastic Demand Frontier

    E-Print Network [OSTI]

    US Residential Energy Demand and Energy Efficiency: A Stochastic Demand Frontier Approach Massimo www.cepe.ethz.ch #12;US Residential Energy Demand and Energy Efficiency: A Stochastic Demand Frontier Approach Page 1 of 25 US Residential Energy Demand and Energy Efficiency: A Stochastic Demand Frontier

  13. #SpaceWeek: Science on the Cosmic Frontier | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed off Energy.gov. Are you sure you wantJoin us for|IdahotheWhat is the FOIARenewable

  14. Experiments at the Cosmic Frontier | U.S. DOE Office of Science (SC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. Category UC-l 1,Energy ConsumersExperimental TestNew Phase

  15. Fort Inge and the Texas frontier, 1849-1869

    E-Print Network [OSTI]

    Smith, Thomas Tyree

    1991-01-01T23:59:59.000Z

    ) May 1991 ABSTRACT Fort Inge and the Texas Frontier, 1849-1869. (May 1991) Thomas Tyree Smith B. S. in Ed. , Southwest Texas State University Chair of Advisory Committee: Dr. Joseph G. Dawson III Now an obscure site near Uvalde, Fort Inge was once...'s Report on the Eighth Nilitary Department, " Cartographic Division, DR 148, RG 77, NA. 12 NOTES 1. Frederick Law Olmsted, A Journey Through Texas: Or A Saddle- Trip On the Southwestern Frontier (New York: Dix, Edwards 6 Co. , 1857; rpr. , Austin...

  16. Power System Extreme Event Detection: The VulnerabilityFrontier

    SciTech Connect (OSTI)

    Lesieutre, Bernard C.; Pinar, Ali; Roy, Sandip

    2007-10-17T23:59:59.000Z

    In this work we apply graph theoretic tools to provide aclose bound on a frontier relating the number of line outages in a gridto the power disrupted by the outages. This frontier describes theboundary of a space relating the possible severity of a disturbance interms of power disruption, from zero to some maximum on the boundary, tothe number line outages involved in the event. We present the usefulnessof this analysis with a complete analysis of a 30 bus system, and presentresults for larger systems.

  17. Life Extinctions By Cosmic Ray Bursts

    E-Print Network [OSTI]

    Arnon Dar; Ari Laor; Nir J. Shaviv

    1997-05-02T23:59:59.000Z

    High energy cosmic ray jets from nearby mergers or accretion induced collapse (AIC) of neutron stars (NS) that hit the atmosphere can produce lethal fluxes of atmospheric muons at ground level, underground and underwater, destroy the ozone layer and radioactivate the environment. They could have caused most of the massive life extinctions on planet Earth in the past 600 My. Biological mutations due to ionizing radiations could have caused the fast appearance of new species after the massive extinctions. An early warning of future extinctions due to NS mergers may be obtained by identifying, mapping and timing all the nearby binary neutron stars systems. A warning of an approaching cosmic ray burst from a nearby NS merger/AIC may be provided by a very intense gamma ray burst which preceeds it.

  18. Cloud a particle beam facility to investigate the influence of cosmic rays on clouds

    E-Print Network [OSTI]

    Kirkby, Jasper

    2001-01-01T23:59:59.000Z

    Palaeoclimatic data provide extensive evidence for solar forcing of the climate during the Holocene and the last ice age, but the underlying mechanism remains a mystery. However recent observations suggest that cosmic rays may play a key role. Satellite data have revealed a surprising correlation between cosmic ray intensity and the fraction of the Earth covered by low clouds \\cite{svensmark97,marsh}. Since the cosmic ray intensity is modulated by the solar wind, this may be an important clue to the long-sought mechanism for solar-climate variability. In order to test whether cosmic rays and clouds are causally linked and, if so, to understand the microphysical mechanisms, a novel experiment known as CLOUD\\footnotemark\\ has been proposed \\cite{cloud_proposal}--\\cite{cloud_addendum_2}. CLOUD proposes to investigate ion-aerosol-cloud microphysics under controlled laboratory conditions using a beam from a particle accelerator, which provides a precisely adjustable and measurable artificial source of cosmic rays....

  19. FRONTIER SYNCHROTRON INFRARED SPECTROSCOPY BEAMLINE UNDER EXTREME CONDITIONS (FIS)

    E-Print Network [OSTI]

    Ohta, Shigemi

    FRONTIER SYNCHROTRON INFRARED SPECTROSCOPY BEAMLINE UNDER EXTREME CONDITIONS (FIS) Proposal Team: L INFORMATION · TECHNIQUE(S): Fourier transform infrared spectroscopy; Raman and visible spectroscopy; Diamond techniques combined with DACs; Laser heating techniques combined with DACs. · SOURCE: Large-gap (90 mm

  20. Frontiers in Catalysis Science and Engineering Seminar Series

    E-Print Network [OSTI]

    in internal combustion engines and power plants. Copper-exchanged promising as selective catalytic reduction ) are a major atmospheric pollutant produced through the combustion of fossil fuels in internal combustionFrontiers in Catalysis Science and Engineering Seminar Series Small Pore Zeolites: Effective

  1. New Frontiers in Solar Physics: Broadband Imaging Spectroscopy with the

    E-Print Network [OSTI]

    , the solar panel of the AASC recommended an integrated suite of instrumentation designed to meetNew Frontiers in Solar Physics: Broadband Imaging Spectroscopy with the Frequency Agile Solar and other astrophysical objects and processes. Outstanding problems in solar physics include the magnetic

  2. Business Intelligence: The Next Frontier for Information Systems Research?

    E-Print Network [OSTI]

    Polz, Martin

    Business Intelligence: The Next Frontier for Information Systems Research? Panel at WITS-20011 1) (http://www.busi.mun.ca/parsons/wits2001/), held New Orleans, LA, USA, Dec. 15-16, 2001, in conjunction not appear in Proceedings, due to lack of space. Abraham Bernstein NYU ­ Stern School of Business 44 West 4th

  3. Business Intelligence: The Next Frontier for Information Systems Research?

    E-Print Network [OSTI]

    Polz, Martin

    Business Intelligence: The Next Frontier for Information Systems Research? Panel at WITS­2001 1 1) (http://www.busi.mun.ca/parsons/wits2001/), held New Orleans, LA, USA, Dec. 15­16, 2001, in conjunction not appear in Proceedings, due to lack of space. Abraham Bernstein NYU -- Stern School of Business 44 West 4

  4. A LETTERS JOURNAL EXPLORING THE FRONTIERS OF PHYSICS

    E-Print Network [OSTI]

    Iglesias, José Roberto

    A LETTERS JOURNAL EXPLORING THE FRONTIERS OF PHYSICS OFFPRINT Coexistence of ferromagnetism in some uranium compounds, is studied in the framework of an underscreened Kondo lattice model within of another class of heavy-fermion systems, uranium compounds, whose behavior is quite different from cerium

  5. Invited Paper New Frontiers of Network Security: The Threat Within

    E-Print Network [OSTI]

    Sanyal, Sugata

    Invited Paper New Frontiers of Network Security: The Threat Within Sugata Sanyal1 , Ajit Shelat2% of information security threats originate from inside the organization. The instances of insider threats have. The Insider threats are generally caused by current or ex-employees, contractors or partners, who have

  6. Frontiers in Catalysis Science and Engineering Seminar Series

    E-Print Network [OSTI]

    Frontiers in Catalysis Science and Engineering Seminar Series On the role of hydrogen of Chemical & Biological Engineering ·University of Wisconsin - Madison Abstract Hydrogen is a frequent principles governing the role of hydrogen in a wide range of catalytic transformations begin to emerge

  7. Frontiers in Computational and Information Sciences Seminar Series

    E-Print Network [OSTI]

    Frontiers in Computational and Information Sciences Seminar Series Stochastic Multiscale Modeling phenomena, where information is lost as part of the coarse-graining procedure, e.g. formulating mesoscale in computational science both on algorithms and applications. A main current thrust is stochastic simulation (in

  8. Frontiers in Computational and Information Sciences Seminar Series

    E-Print Network [OSTI]

    Frontiers in Computational and Information Sciences Seminar Series "An Overview of the SciDAC-3 California Information Sciences Institute Abstract Over the next five years (2012--2016), computational scientists working on behalf of the Department of Energy's Office of Science (DOE SC) will exploit a new

  9. Software Engineering Frontiers in Computational Science and Engineering

    E-Print Network [OSTI]

    Hallstrom, Jason

    into the behavior of complex systems. Computational science and engineering uses computational methods to conductSoftware Engineering Frontiers in Computational Science and Engineering D. E. Stevenson Department­ quire the multidisciplinary teamwork of engineers plus com­ puter, mathematical and physical scientists

  10. The Amazon Frontier of Land-Use Change: Croplands and

    E-Print Network [OSTI]

    Vermont, University of

    -cropping intensification. Greenhouse gas emissions are estimated for the period 2001­06 due to conversion of natural; Hansen et al. 2008). Economic de- velopment and global markets have driven large-scale conversionsThe Amazon Frontier of Land-Use Change: Croplands and Consequences for Greenhouse Gas Emissions

  11. Frontiers in Catalysis Science and Engineering Seminar Series

    E-Print Network [OSTI]

    Frontiers in Catalysis Science and Engineering Seminar Series "Frustrated Lewis Pairs": Metal and applied to develop metal-free hydrogenations for C=N bonds in a variety of organic substrates. In addition, alkynes, cyclopropanes, CO2 and N2O. The implications of the discovery of such systems to catalysis

  12. Frontiers in Catalysis Science and Engineering Seminar Series

    E-Print Network [OSTI]

    Frontiers in Catalysis Science and Engineering Seminar Series Heterogenized M-Salen Catalysts complexes are widely applied as catalysts for numerous important enantioselective reactions. The reactions catalysis (e.g. Co-salen for epoxide ring-opening or Al-salen conjugate additions of cyanide). The design

  13. APOLLO 7 40th Anniversary Frontiers of Flight Museum

    E-Print Network [OSTI]

    APOLLO 7 40th Anniversary Frontiers of Flight Museum Dallas, Texas 17 October 2008 N. A. Armstrong., the first Apollo crew sat in their Apollo 1 spacecraft during a simulated countdown test when tragedy struck be their replacement. They had been completely prepared to fly that original Apollo Command Module if it had been

  14. RESEARCH IN PARTICLE PHYSICS

    SciTech Connect (OSTI)

    Kearns, Edward [Boston Universiy] [Boston Universiy

    2013-07-12T23:59:59.000Z

    This is the final report for the Department of Energy Grant to Principal Investigators in Experimental and Theoretical Particle Physics at Boston University. The research performed was in the Energy Frontier at the LHC, the Intensity Frontier at Super-Kamiokande and T2K, the Cosmic Frontier and detector R&D in dark matter detector development, and in particle theory.

  15. Experiments at the Intensity Frontier | U.S. DOE Office of Science (SC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist. Category UC-l 1,Energy ConsumersExperimental TestNew

  16. The Cosmic Organism Theory

    E-Print Network [OSTI]

    Ding-Yu Chung; Volodymyr Krasnoholovets

    2005-12-05T23:59:59.000Z

    We present the cosmic organism theory in which all visible and invisible matter has different cosmic genetic expressions. The cosmic gene includes codes for the object structure and the space structure. The cosmic digital code for the object structure consists of full object (1, 2, and 3 for particle, string, and membrane, respectively) and empty object (0) as anti de Sitter space (AdS). The tessellation lattice of empty objects is tessellattice. The decomposition of a full object in tessellattice results in the AdS/CFT (conformal field theory) duality. The digital code for the object structure accounts for the AdS/CFT duality, the dS/bulk duality, and gravity. The digital code for the space structure consists of 1 and 0 for attachment space and detachment space, respectively. Attachment space attaches to object permanently at zero speed or reversibly at the speed of light. Detachment space detaches from the object irreversibly at the speed of light. The combination of attachment space and detachment space results in miscible space, binary lattice space or binary partition space. Miscible space represents special relativity. Binary lattice space consists of multiple quantized units of attachment space separated from one another by detachment space. Binary lattice space corresponds to the nilpotent universal computational rewrite system (NUCRS) by Diaz and Rowlands. The gauge force fields and wavefunction are in binary lattice space. With tessellattice and binary lattice space, 11D brane is reducing to 4D particle surrounded by gravity and the gauge force fields. The cosmic dimension varies due to different speeds of light in different dimensional space-times and the increase of mass.

  17. Transverse beam shape measurements of intense proton beams using optical transition radiation

    SciTech Connect (OSTI)

    Scarpine, Victor E.; /Fermilab

    2012-03-01T23:59:59.000Z

    A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.

  18. 24. Cosmic rays 1 24. COSMIC RAYS

    E-Print Network [OSTI]

    fraction of these particles may be primary is a question of current interest. Apart from particles are affected by the geomagnetic field, which they must penetrate to reach the top of the atmosphere. Thus measure a quantity that is related to total energy per particle. The units of differential intensity I

  19. 26. Cosmic rays 1 26. COSMIC RAYS

    E-Print Network [OSTI]

    fraction of these particles may be primary is a question of current interest. Apart from particles are affected by the geomagnetic field, which they must penetrate to reach the top of the atmosphere. Thus measure a quantity that is related to total energy per particle. The units of differential intensity I

  20. PILOT and cosmic shear

    E-Print Network [OSTI]

    W. Saunders

    2008-01-29T23:59:59.000Z

    Cosmic shear offers a remarkbly clean way to measure the equation of state of the Universe and its evolution. Resolution over a wide field is paramount, and Antarctica offers unique possibilities in this respect. There is an order of magnitude gain in speed over temperate sites, or a factor three in surface density. This means that PILOT outperforms much larger telescopes elsewhere, and can compete with the proposed DUNE space mission. Keywords: Antarctic astronomy, Surveys, Adaptive optics, Weak lensing

  1. Geochemical Prospecting of Hydrocarbons in Frontier Basins of India* By

    E-Print Network [OSTI]

    B. Kumar; D. J. Patil; G. Kalpana; C. Vishnu Vardhan

    India has 26 sedimentary basins with a basinal area of approximately 1.8x 10 6 km 2 (excluding deep waters), out of which seven are producing basins and two have proven potential. Exploration efforts in other basins, called “frontier basins ” are in progress. These basins are characterized by varied geology, age, tectonics, and depositional environments. Hydrocarbon shows in many of these basins are known, and in few basins oil and gas have flowed in commercial /non-commercial quantities. Within the framework of India Hydrocarbon Vision – 2025 and New Exploration Licensing Policy, there is a continuous increase in area under active exploration. The asset management concept with multi-disciplinary teams has created a demand for synergic application of risk-reduction technologies, including surface geochemical surveys. National Geophysical Research Institute (NGRI), Hyderabad, India has initiated/planned surface geochemical surveys composed of gas chromatographic and carbon isotopic analyses in few of the frontier basins of India. The adsorbed soil gas data in one of the basins (Saurashtra basin, Gujarat) has shown varied concentrations of CH4 to C4H10. The C1 concentration varies between 3 to 766 ppb and ??C2+, 1 to 543 ppb. This basin has thin soil cover and the Mesozoic sediments (probable source rocks) are overlain by thick cover of Deccan Traps. The scope and perspective of geochemical surveys in frontier basins of India are presented here.

  2. Frontiers in X-Ray Science

    SciTech Connect (OSTI)

    Linda Young

    2011-02-23T23:59:59.000Z

    The year 2010 marked the fiftieth anniversary of the optical laser and the first anniversary of the world's first hard x-ray free-electron laser, the Linac Coherent Light Source (LCLS) at SLAC. This exciting, new accelerator-based source of x-rays provides peak brilliances roughly a billion times greater than currently available from synchrotron sources such as the Advanced Photon Source at Argonne, and thus explores a qualitatively different parameter space. This talk will describe the first experiments at the LCLS aimed at understanding the nature of high intensity x-ray interactions, related applications in ultrafast imaging on the atomic scale and sketch nascent plans for the extension of both linac and storage-ring based photon sources.

  3. The Origin of Cosmic Rays

    ScienceCinema (OSTI)

    Pasquale Blasi

    2010-01-08T23:59:59.000Z

    Cosmic Rays reach the Earth from space with energies of up to more than 1020 eV, carrying information on the most powerful particle accelerators that Nature has been able to assemble. Understanding where and how cosmic rays originate has required almost one century of investigations, and, although the last word is not written yet, recent observations and theory seem now to fit together to provide us with a global picture of the origin of cosmic rays of unprecedented clarity. Here we will describe what we learned from recent observations of astrophysical sources (such as supernova remnants and active galaxies) and we will illustrate what these observations tell us about the physics of particle acceleration and transport. We will also discuss the ?end? of the Galactic cosmic ray spectrum, which bridges out attention towards the so called ultra high energy cosmic rays (UHECRs). At ~1020 eV the gyration scale of cosmic rays in cosmic magnetic fields becomes large enough to allow us to point back to their sources, thereby allowing us to perform ?cosmic ray astronomy?, as confirmed by the recent results obtained with the Pierre Auger Observatory. We will discuss the implications of these observations for the understanding of UHECRs, as well as some questions which will likely remain unanswered and will be the target of the next generation of cosmic ray experiments.

  4. Energy Frontier Research Center Materials Science of Actinides (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Burns, Peter (Director, Materials Science of Actinides); MSA Staff

    2011-11-03T23:59:59.000Z

    'Energy Frontier Research Center Materials Science of Actinides' was submitted by the EFRC for Materials Science of Actinides (MSA) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. MSA is directed by Peter Burns at the University of Notre Dame, and is a partnership of scientists from ten institutions.The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  5. The Center for Frontiers of Subsurface Energy Security (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Pope, Gary A. (Director, Center for Frontiers of Subsurface Energy Security); CFSES Staff

    2011-11-03T23:59:59.000Z

    'The Center for Frontiers of Subsurface Energy Security (CFSES)' was submitted to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CFSES is directed by Gary A. Pope at the University of Texas at Austin and partners with Sandia National Laboratories. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  6. RURAL-FRONTIER MIGRATION AND DEFORESTATION IN THE SIERRA DE LACANDON NATIONAL PARK, GUATEMALA

    E-Print Network [OSTI]

    Lopez-Carr, David

    RURAL-FRONTIER MIGRATION AND DEFORESTATION IN THE SIERRA DE LACANDON NATIONAL PARK, GUATEMALA-frontier Migration and Deforestation in the Sierra de Lacandón National Park, Guatemala (Under the direction of deforestation in the Sierra de Lacandón Park (SLNP), Petén, Guatemala. To explore the first cause

  7. FNAL Proton Source High Intensity Operations and Beam Loss Control

    E-Print Network [OSTI]

    Garcia, F G

    2014-01-01T23:59:59.000Z

    The 40-year-old Fermilab Proton Source machines, constituted by the Pre-Injector, Linac and the synchrotron Booster, have been the workhorse of the Fermi National Accelerator Laboratory (Fermilab). During this time, the High Energy Physics Program has demanded an increase in proton throughput, especially during the past decade with the beginning of the neutrino program at Fermilab. In order to achieve a successful program, major upgrades and changes were made in Booster. Once again, the Proton Source has been charged to double their beam throughput, while maintain the present residual activation levels, to meet the laboratory Intensity Frontier program goals until new machines are built and operational to replace the Proton Source machines. This paper discusses the present performance of Booster and the plans involved in reaching even higher intensities.

  8. Extreme Cosmic String

    E-Print Network [OSTI]

    P. F. Gonzalez-Diaz

    1995-08-28T23:59:59.000Z

    This paper deals with the geometry of supermassive cosmic strings. We have used an approach that enforces the spacetime of cosmic strings to also satisfy the conservation laws of a cylindric gravitational topological defect, that is a spacetime kink. In the simplest case of kink number unity, the entire energy range of supermassive strings becomes then quantized so that only cylindrical defects with linear energy density $G\\mu=1/4$ (critical string) and $G\\mu=1/2$ (extreme string) are allowed to occur in this range. It has been seen that the internal spherical coordinate $\\theta$ of the string metric embedded in an Euclidean three-space also evolves on imaginary values, leading to the creation of a covering shell of broken phase that protects the core with trapped energy, even for $G\\mu=1/2$. Then the conical singularity becomes a removable horizaon singularity. We re-express the extreme string metric in the Finkelstein- McCollum standard form and remove the geodesic incompleteness by using the Kruskal technique. The z=const. sections of the resulting metric are the same as the hemispherical section of the metric of a De Sitter kink. Some physical consequences from these results, including the possibility that the extreme string drives inflation and thermal effects in its core, are also discussed.

  9. Single cell analysis: the new frontier in 'Omics'

    SciTech Connect (OSTI)

    Wang, Daojing; Bodovitz, Steven

    2010-01-14T23:59:59.000Z

    Cellular heterogeneity arising from stochastic expression of genes, proteins, and metabolites is a fundamental principle of cell biology, but single cell analysis has been beyond the capabilities of 'Omics' technologies. This is rapidly changing with the recent examples of single cell genomics, transcriptomics, proteomics, and metabolomics. The rate of change is expected to accelerate owing to emerging technologies that range from micro/nanofluidics to microfabricated interfaces for mass spectrometry to third- and fourth-generation automated DNA sequencers. As described in this review, single cell analysis is the new frontier in Omics, and single cell Omics has the potential to transform systems biology through new discoveries derived from cellular heterogeneity.

  10. The Smith plan, Texas frontier defense in the 1850's

    E-Print Network [OSTI]

    Frysinger, Victor Francis

    1975-01-01T23:59:59.000Z

    - bat the Indians from the annexation of Texas in 1845 up until the departure of General Persifor F . Smith in April, 1856. The early years of statehood were filled with confusion, dis- organization, and disunity as far as frontier defense.... General Smith in Texas, 1851-1856 IV. Aftermath and Evaluation 24 85 Appendix: Status of Forces in Texas, 1851-1856 . 93 Bibliography 105 Vita 113 LIST OF MAPS Map 1 ACTIVE MILITARY POSTS IN TEXAS, 1849 2 THE SMITH PLAN COMPLETED& 1852 3 ACT1VE...

  11. Expanding the Frontiers of Visual Analytics and Visualization

    SciTech Connect (OSTI)

    Dill, John; Earnshaw, Rae; Kasik, David; Vince, John; Wong, Pak C.

    2012-05-31T23:59:59.000Z

    Expanding the Frontiers of Visual Analytics and Visualization contains international contributions by leading researchers from within the field. Dedicated to the memory of Jim Thomas, the book begins with the dynamics of evolving a vision based on some of the principles that Jim and colleagues established and in which Jim’s leadership was evident. This is followed by chapters in the areas of visual analytics, visualization, interaction, modelling, architecture, and virtual reality, before concluding with the key area of technology transfer to industry.

  12. Lab's Frontiers in Science lectures focus on epigenetics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your Home asLCLS ExperimentalFiveVentureFrontiers in Science

  13. Frontiers in Science Lectures focus on saving energy through

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA)Budget(DANCE)FrequentlyLectures » Frontiers

  14. Frontier, North Dakota: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdf Jump1946865°, -86.0529604° ShowCounty, California:Frontier, North Dakota:

  15. Earthquake triggering discussed in three Frontiers in Science lectures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract ManagementDiscoveringESnet UpdateEarth Week event all aboutFrontiers

  16. Ultrahigh Energy Cosmic Rays Detection

    E-Print Network [OSTI]

    Carla Aramo

    2005-09-06T23:59:59.000Z

    The paper describes methods used for the detection of cosmic rays with energies above 10^18 eV (UHECR, UltraHigh Energy Cosmic Rays). It had been anticipated there would be a cutoff in the energy spectrum of primary cosmic rays around 3 10^19 eV induced by their interaction with the 2.7 K primordial photons. This has become known as the GZK cutoff. However, several showers have been detected with estimated primary energy exceeding this limit.

  17. Cosmic Rays at the Knee

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2006-08-25T23:59:59.000Z

    Several kinds of measurements are combined in an attempt to obtain a consistent estimate of the spectrum and composition of the primary cosmic radiation through the knee region. Assuming that the knee is a signal of the high-energy end of a galactic cosmic-ray population, I discuss possible signatures of a transition to an extra-galactic population and how they might be detected.

  18. COSMIC-RAY DIFFUSION IN A SECTORED MAGNETIC FIELD IN THE DISTANT HELIOSHEATH

    SciTech Connect (OSTI)

    Florinski, V. [Department of Physics, University of Alabama, Huntsville, AL 35899 (United States); Alouani-Bibi, F.; Guo, X. [Center for Space Plasma and Aeronomic Research, University of Alabama, Huntsville, AL 35899 (United States); Kota, J. [Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States)

    2012-07-20T23:59:59.000Z

    Very high intensities of galactic cosmic rays measured by Voyager 1 in the heliosheath appear to be incompatible with the presence of a modulation 'wall' near the heliopause produced by a pile up of the heliospheric magnetic field. We propose that the modulation wall is a structure permeable to cosmic rays as a result of a sectored magnetic field topology compressed by plasma slowdown on approach to the heliopause and stretched to high latitudes by latitudinal flows in the heliosheath. The tightly folded warped current sheet permits efficient cosmic-ray transport in the radial direction via a drift-like mechanism. We show that when stochastic variations in the sector widths are taken into account, particle transport becomes predominantly diffusive both along and across the magnetic sectors. Using a test-particle model for cosmic rays in the heliosheath we investigate the dependence of the diffusion coefficients on the properties of the sector structure and on particle energy.

  19. SPECTROSCOPIC REDSHIFTS OF GALAXIES WITHIN THE FRONTIER FIELDS

    SciTech Connect (OSTI)

    Ebeling, Harald; Ma, Cheng-Jiun; Barrett, Elizabeth [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2014-04-01T23:59:59.000Z

    We present a catalog of 1921 spectroscopic redshifts measured in the fields of the massive galaxy clusters MACSJ0416.1–2403 (z = 0.397), MACSJ0717.5+3745 (z = 0.546), and MACSJ1149.5+2223 (z = 0.544), i.e., three of the four clusters selected by Space Telescope Science Institute as the targets of the Frontier Fields (FFs) initiative for studies of the distant Universe via gravitational lensing. Compiled in the course of the Massive Cluster Survey project (MACS) that detected the FF clusters, this catalog is provided to the community for three purposes: (1) to allow the identification of cluster members for studies of the galaxy population of these extreme systems, (2) to facilitate the removal of unlensed galaxies and thus reduce shear dilution in weak-lensing analyses, and (3) to improve the calibration of photometric redshifts based on both ground- and spacebased observations of the FF clusters.

  20. Frontier market analysis : a case study of Iraq's real estate industry

    E-Print Network [OSTI]

    Watkins, Steven C., Jr. (Steven Charles)

    2010-01-01T23:59:59.000Z

    Success in frontier markets could mean high returns for real estate developers and investors. In order to succeed, companies must determine how to provide their products or services in an environment that may not necessarily ...

  1. Apply: Building Energy Efficiency Frontiers and Innovation Technologies (BENEFIT)- 2015 Funding Opportunity Announcement

    Broader source: Energy.gov [DOE]

    Closed Application Deadline: January 12, 2015 This Building Energy Efficiency Frontiers and Innovations Technologies (BENEFIT) 2015 FOA contributes to advancement in two core technological areas: non-vapor compression HVAC technologies and advanced vapor compression HVAC technologies.

  2. Basin analog approach answers characterization challenges of unconventional gas potential in frontier basins

    E-Print Network [OSTI]

    Singh, Kalwant

    2007-04-25T23:59:59.000Z

    To continue increasing the energy supply to meet global demand in the coming decades, the energy industry needs creative thinking that leads to the development of new energy sources. Unconventional gas resources, especially those in frontier basins...

  3. PARC - Scientific Exchange Program (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Blankenship, Robert E. (Director, Photosynthetic Antenna Research Center); PARC Staff

    2011-11-03T23:59:59.000Z

    'PARC - Scientific Exchange Program' was submitted by the Photosynthetic Antenna Research Center (PARC) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. PARC, an EFRC directed by Robert E. Blankenship at Washington University in St. Louis, is a partnership of scientists from ten institutions. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  4. Electricity: The Energy of Tomorrow (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Abruna, Hector D. (Director, Energy Materials Center at Cornell); emc2 Staff

    2011-11-03T23:59:59.000Z

    'Electricity: the Energy of Tomorrow' was submitted by the Energy Materials Center at Cornell (emc2) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. emc2, an EFRC directed by Hector D. Abruna at Cornell University (lead) is a partnership between Cornell and Lawrence Berkeley National Laboratory. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  5. Electricity: The Energy of Tomorrow (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    SciTech Connect (OSTI)

    Abruna, Hector D. (Director, Energy Materials Center at Cornell) [Director, Energy Materials Center at Cornell; emc2 Staff

    2011-05-01T23:59:59.000Z

    'Electricity: the Energy of Tomorrow' was submitted by the Energy Materials Center at Cornell (emc2) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. emc2, an EFRC directed by Hector D. Abruna at Cornell University (lead) is a partnership between Cornell and Lawrence Berkeley National Laboratory. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  6. Light intensity compressor

    DOE Patents [OSTI]

    Rushford, Michael C. (Livermore, CA)

    1990-01-01T23:59:59.000Z

    In a system for recording images having vastly differing light intensities over the face of the image, a light intensity compressor is provided that utilizes the properties of twisted nematic liquid crystals to compress the image intensity. A photoconductor or photodiode material that is responsive to the wavelength of radiation being recorded is placed adjacent a layer of twisted nematic liquid crystal material. An electric potential applied to a pair of electrodes that are disposed outside of the liquid crystal/photoconductor arrangement to provide an electric field in the vicinity of the liquid crystal material. The electrodes are substantially transparent to the form of radiation being recorded. A pair of crossed polarizers are provided on opposite sides of the liquid crystal. The front polarizer linearly polarizes the light, while the back polarizer cooperates with the front polarizer and the liquid crystal material to compress the intensity of a viewed scene. Light incident upon the intensity compressor activates the photoconductor in proportion to the intensity of the light, thereby varying the field applied to the liquid crystal. The increased field causes the liquid crystal to have less of a twisting effect on the incident linearly polarized light, which will cause an increased percentage of the light to be absorbed by the back polarizer. The intensity of an image may be compressed by forming an image on the light intensity compressor.

  7. Imaging the High Energy Cosmic Ray Sky

    E-Print Network [OSTI]

    Haviland, David

    Imaging the High Energy Cosmic Ray Sky PETTER HOFVERBERG Licentiate Thesis Stockholm, Sweden 2006 #12;#12;Licentiate Thesis Imaging the High Energy Cosmic Ray Sky Petter Hofverberg Particle

  8. Measuring the cosmic shear in Fourier space

    E-Print Network [OSTI]

    Zhang, Jun

    2008-01-01T23:59:59.000Z

    Measuring the Cosmic Shear in Fourier Space Bernardeau F. ,the Cosmic Shear in Fourier Space Jun Zhang ? Department ofshould be carried out in Fourier space, in which the point

  9. EFRC:CST at the University of Texas at Austin - A DOE Energy Frontier Research Center (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Zhu, Xiaoyang (Director, Understanding Charge Separation and Transfer at Interfaces in Energy Materials); CST Staff

    2011-11-03T23:59:59.000Z

    'EFRC:CST at the University of Texas at Austin - A DOE Energy Frontier Research Center' was submitted by the EFRC for Understanding Charge Separation and Transfer at Interfaces in Energy Materials (EFRC:CST) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. EFRC:CST is directed by Xiaoyang Zhu at the University of Texas at Austin in partnership with Sandia National Laboratories. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  10. Center for Defect Physics - Energy Frontier Research Center (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Stocks, G. Malcolm (Director, Center for Defect Physics in Structural Materials); CDP Staff

    2011-11-03T23:59:59.000Z

    'Center for Defect Physics - Energy Frontier Research Center' was submitted by the Center for Defect Physics (CDP) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CDP is directed by G. Malcolm Stocks at Oak Ridge National Laboratory, and is a partnership of scientists from nine institutions: Oak Ridge National Laboratory (lead); Ames Laboratory; Brown University; University of California, Berkeley; Carnegie Mellon University; University of Illinois, Urbana-Champaign; Lawrence Livermore National Laboratory; Ohio State University; and University of Tennessee. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  11. Clusters and the Cosmic Web

    E-Print Network [OSTI]

    Rien van de Weygaert

    2006-07-24T23:59:59.000Z

    We discuss the intimate relationship between the filamentary features and the rare dense compact cluster nodes in this network, via the large scale tidal field going along with them, following the cosmic web theory developed Bond et al. The Megaparsec scale tidal shear pattern is responsible for the contraction of matter into filaments, and its link with the cluster locations can be understood through the implied quadrupolar mass distribution in which the clusters are to be found at the sites of the overdense patches. We present a new technique for tracing the cosmic web, identifying planar walls, elongated filaments and cluster nodes in the galaxy distribution. This will allow the practical exploitation of the concept of the cosmic web towards identifying and tracing the locations of the gaseous WHIM. These methods, the Delaunay Tessellation Field Estimator (DTFE) and the Morphology Multiscale Filter (MMF) find their basis in computational geometry and visualization.

  12. Quadratic superconducting cosmic strings revisited

    E-Print Network [OSTI]

    Mustapha Azreg-Aïnou

    2008-02-22T23:59:59.000Z

    It has been shown that 5-dimensional general relativity action extended by appropriate quadratic terms admits a singular superconducting cosmic string solution. We search for cosmic strings endowed with similar and extended physical properties by directly integrating the non-linear matrix field equations thus avoiding the perturbative approach by which we constructed the above-mentioned \\textsl{exact} solution. The most general superconducting cosmic string, subject to some constraints, will be derived and shown to be mathematically \\textsl{unique} up to linear coordinate transformations mixing its Killing vectors. The most general solution, however, is not globally equivalent to the old one due to the existence of Killing vectors with closed orbits.

  13. High-energy Cosmic Rays

    E-Print Network [OSTI]

    Thomas K. Gaisser; Todor Stanev

    2005-10-11T23:59:59.000Z

    After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesting are two features of the spectrum, the `knee' above $10^{15}$ eV and the `ankle' above $10^{18}$ eV. An important question is whether the highest energy particles are of extra-galactic origin and, if so, at what energy the transition occurs. A theme common to all energy ranges is use of nuclear abundances as a tool for understanding the origin of the cosmic radiation.

  14. Cosmic Particle Acceleration: Basic Issues

    E-Print Network [OSTI]

    T. W. Jones

    2000-12-22T23:59:59.000Z

    Cosmic-rays are ubiquitous, but their origins are surprisingly difficult to understand. A review is presented of some of the basic issues common to cosmic particle accelerators and arguments leading to the likely importance of diffusive shock acceleration as a general explanation. The basic theory of diffusive shock acceleration is outlined, followed by a discussion of some of the key issues that still prevent us from a full understanding of its outcomes. Some recent insights are mentioned at the end that may help direct ultimate resolution of our uncertainties.

  15. The Intense Radiation Gas

    E-Print Network [OSTI]

    M. Marklund; P. K. Shukla; B. Eliasson

    2005-03-08T23:59:59.000Z

    We present a new dispersion relation for photons that are nonlinearly interacting with a radiation gas of arbitrary intensity due to photon-photon scattering. It is found that the photon phase velocity decreases with increasing radiation intensity, it and attains a minimum value in the limit of super-intense fields. By using Hamilton's ray equations, a self-consistent kinetic theory for interacting photons is formulated. The interaction between an electromagnetic pulse and the radiation gas is shown to produce pulse self-compression and nonlinear saturation. Implications of our new results are discussed.

  16. Temporal and energy behavior of cosmic ray fluxes in the periods of low solar activity

    E-Print Network [OSTI]

    Bazilevskaya, G A; Krainev, M B; Makhmutov, V S; Svirzhevskaya, A K; Svirzhevsky, N S

    2014-01-01T23:59:59.000Z

    Modulation of galactic cosmic ray intensity is governed by several mechanisms including diffusion, convection, adiabatic energy losses and drift. Relative roles of these factors change in the course of an 11-year solar cycle. That can result in the changes in the energy dependence of the 11-year cosmic ray modulation. The minimum between the solar cycles 23 and 24 was extremely deep and long-lasting which led to the record high cosmic ray fluxes low-energy particles dominating. This was a signature of unusually soft energy spectrum of the cosmic rays. In this work we examine the energy dependence of the 11-year modulation during the last three solar cycles and argue that a soft energy spectrum was observed in the minimum of each cycle however only for particles below of energy around 10 GeV. From mid 1980s the energy dependence of cosmic rays became softer from minimum to minimum of solar activity. The work is based on the cosmic ray data of the spacecraft, balloon-borne and the ground-based observations.

  17. Multipole analysis in cosmic topology

    E-Print Network [OSTI]

    Peter Kramer

    2010-09-29T23:59:59.000Z

    Low multipole amplitudes in the Cosmic Microwave Background CMB radiation can be explained by selection rules from the underlying multiply-connected homotopy. We apply a multipole analysis to the harmonic bases and introduce point symmetry.We give explicit results for two cubic 3-spherical manifolds and lowest polynomial degrees, and derive three new spherical 3-manifolds.

  18. Reheating and Cosmic String Production

    E-Print Network [OSTI]

    Chao-Jun Feng; Xian Gao; Miao Li; Wei Song; Yushu Song

    2008-01-04T23:59:59.000Z

    We compute the string production rate at the end of inflation, using the string spectrum obtained in \\lss in a near-de Sitter space. Our result shows that highly excited strings are hardly produced, thus the simple slow-roll inflation alone does not offer a cosmic string production mechanism.

  19. Solar radiation intensity calculations

    E-Print Network [OSTI]

    Levine, Randolph Steven

    1978-01-01T23:59:59.000Z

    SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Submitted to the Graduate College of Texas A&M University in partia'l fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject...: Physics SOLAR RADIATION INTENSITY CALCULATIONS A Thesis by RANDOLPH STEVEN LEVINE Approved as to style and content by: (Chairman of Committee) (Member) (Member) ( member) (Head of Department) December 1978 f219 037 ABSTRACT Solar Radiation...

  20. Frontiers of in situ electron microscopy

    SciTech Connect (OSTI)

    Zheng, Haimei [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhu, Yimei [Brookhaven National Lab. (BNL), Upton, NY (United States); Meng, Shirley Ying [Univ. of California-San Diego, San Diego, CA (United States)

    2015-01-01T23:59:59.000Z

    In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by in this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.

  1. Diagnostic potential of cosmic-neutrino absorption spectroscopy

    SciTech Connect (OSTI)

    Barenboim, Gabriela; /Valencia U.; Mena Requejo, Olga; Quigg, Chris; /Fermilab

    2004-12-01T23:59:59.000Z

    Annihilation of extremely energetic cosmic neutrinos on the relic-neutrino background can give rise to absorption lines at energies corresponding to formation of the electroweak gauge boson Z{sup 0}. The positions of the absorption dips are set by the masses of the relic neutrinos. Suitably intense sources of extremely energetic (10{sup 21} - 10{sup 25}-eV) cosmic neutrinos might therefore enable the determination of the absolute neutrino masses and the flavor composition of the mass eigenstates. Several factors--other than neutrino mass and composition--distort the absorption lines, however. We analyze the influence of the time-evolution of the relic-neutrino density and the consequences of neutrino decay. We consider the sensitivity of the lineshape to the age and character of extremely energetic neutrino sources, and to the thermal history of the Universe, reflected in the expansion rate. We take into account Fermi motion arising from the thermal distribution of the relic-neutrino gas. We also note the implications of Dirac vs. Majorana relics, and briefly consider unconventional neutrino histories. We ask what kinds of external information would enhance the potential of cosmic-neutrino absorption spectroscopy, and estimate the sensitivity required to make the technique a reality.

  2. Diagnostic potential of cosmic-neutrino absorption spectroscopy

    SciTech Connect (OSTI)

    Barenboim, Gabriela; Requejo, Olga Mena; Quigg, Chris [Departament de Fisica Teorica, Universitat de Valencia, Carrer Dr. Moliner 50, E-46100 Burjassot, Valencia (Spain); Theoretical Physics Department, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510 (United States)

    2005-04-15T23:59:59.000Z

    Annihilation of extremely energetic cosmic neutrinos on the relic-neutrino background can give rise to absorption lines at energies corresponding to formation of the electroweak gauge boson Z{sup 0}. The positions of the absorption dips are set by the masses of the relic neutrinos. Suitably intense sources of extremely energetic (10{sup 21}-10{sup 25}-eV) cosmic neutrinos might therefore enable the determination of the absolute neutrino masses and the flavor composition of the mass eigenstates. Several factors--other than neutrino mass and composition--distort the absorption lines, however. We analyze the influence of the time evolution of the relic-neutrino density and the consequences of neutrino decay. We consider the sensitivity of the line shape to the age and character of extremely energetic neutrino sources, and to the thermal history of the Universe, reflected in the expansion rate. We take into account Fermi motion arising from the thermal distribution of the relic-neutrino gas. We also note the implications of Dirac vs. Majorana relics, and briefly consider unconventional neutrino histories. We ask what kinds of external information would enhance the potential of cosmic-neutrino absorption spectroscopy, and estimate the sensitivity required to make the technique a reality.

  3. Ohio State's researchers to collaborate on three new Ohio Third Frontier photovoltaics grants Ohio State's Institute for Materials Research (IMR) is the central collaborator on three Ohio Third Frontier Photovoltaics

    E-Print Network [OSTI]

    Ohio State's researchers to collaborate on three new Ohio Third Frontier photovoltaics grants Ohio Photovoltaics Program (PVP) projects recommended for funding by the Ohio Third Frontier Commission. The goal of the PVP is to accelerate the development and growth of the photovoltaics industry in Ohio by supporting

  4. Cash crops, smallholder decision-making and institutional interactions in a closing-frontier: Calakmul, Campeche, Mexico

    E-Print Network [OSTI]

    Robeson, Scott M.

    -frontier: Calakmul, Campeche, Mexico Author(s): Eric Keys and Rinku Roy Chowdhury Source: Journal of Latin American decision-making and institutional interactions in a closing frontier: Calakmul, Campeche, Mexico Eric Keys and policy factors in the municipality of Calakmul in Campeche, Mexico. Jalapeno chili is the foremost market

  5. AAPPS Bulletin April 2008, Vol. 18, No. 2 11 A Perspective of Frontiers in Modern Condensed Matter Physics

    E-Print Network [OSTI]

    Yeh, Nai-Chang

    Physics A Perspective of Frontiers in Modern Condensed Matter Physics Nai-Chang Yeh Department of Physics, California Institute of Technology, Pasadena, California 91125, USA Articles Modern condensed matter physics research frontiers in modern condensed matter physics without getting too much into the technical details

  6. Energy Intensity Strategy 

    E-Print Network [OSTI]

    Rappolee, D.; Shaw, J.

    2008-01-01T23:59:59.000Z

    Our presentation will cover how we began the journey of conserving energy at our facility. We’ll discuss a basic layout of our energy intensity plan and the impact our team has had on the process, what tools we’re using, what goals have been...

  7. Numerical Simulations Unravel the Cosmic Web

    E-Print Network [OSTI]

    C. -A. Faucher-Giguere; A. Lidz; L. Hernquist

    2008-03-03T23:59:59.000Z

    The universe is permeated by a network of filaments, sheets, and knots collectively forming a "cosmic web.'' The discovery of the cosmic web, especially through its signature of absorption of light from distant sources by neutral hydrogen in the intergalactic medium, exemplifies the interplay between theory and experiment that drives science, and is one of the great examples in which numerical simulations have played a key and decisive role. We recount the milestones in our understanding of cosmic structure, summarize its impact on astronomy, cosmology, and physics, and look ahead by outlining the challenges faced as we prepare to probe the cosmic web at new wavelengths.

  8. CABS: Green Energy for Our Nation's Future (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    SciTech Connect (OSTI)

    Jan Jaworski (Director, Center for Advanced Biofuel Systems) [Director, Center for Advanced Biofuel Systems; Sayre, Richard T. (previous Director) [previous Director; CABS Staff

    2011-05-01T23:59:59.000Z

    'CABS: Green Energy for our Nation's Future' was submitted by the Center for Advanced Biofuel Systems (CABS) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CABS, an EFRC directed by Jan Jaworski at the Donald Danforth Plant Science Center is a partnership of scientists from five institutions: Donald Danforth Plant Science Center (lead), Michigan State University, the University of Nebraska, New Mexico Consortium/LANL, and Washington State University. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  9. Liquid Sunshine to Fuel Your Car (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    SciTech Connect (OSTI)

    Cosgrove, Daniel (Director, Center for Lignocellulose Structure and Formation) [Director, Center for Lignocellulose Structure and Formation; CLSF Staff

    2011-05-01T23:59:59.000Z

    'Liquid Sunshine to Fuel Your Car' was submitted by the Center for Lignocellulose Structure and Formation (CLSF) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CLSF is directed by Daniel Cosgrove at Pennsylvania State University and is a partnership of scientists from three institutions: Penn State (lead), North Caroline State University, and Virginia Tech University. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Lignocellulose Structure and Formation is 'to dramatically increase our fundamental knowledge of the formation and physical interactions of bio-polymer networks in plant cell walls to provide a basis for improved methods for converting biomass into fuels.' Research topics are: biofuels (biomass), membrane, interfacial characterization, matter by design, and self-assembly.

  10. Battle against Phonons (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum

    ScienceCinema (OSTI)

    Chen, Gang (Director, Solid-State Solar-Thermal Energy Conversion Center); S3TEC Staff

    2011-11-02T23:59:59.000Z

    'Battle against Phonons' was submitted by the Solid-State Solar-Thermal Energy Conversion (S3TEC) EFRC to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. This video was selected as one of five winners by a distinguished panel of judges for the special award, 'Best with Popcorn'. S3TEC, an EFRC directed by Gang Chen at the Massachusetts Institute of Technology is a partnership of scientists from four research institutions: MIT (lead), Oak Ridge National Laboratory, Boston College, and Rensselaer Polytechnic Institute. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Solid-State Solar Thermal Energy Conversion Center is 'to create novel, solid-state materials for the conversion of sunlight into electricity using thermal and photovoltaic processes.' Research topics are: solar photovoltaic, photonic, metamaterial, optics, solar thermal, thermoelectric, phonons, thermal conductivity, defects, ultrafast physics, interfacial characterization, matter by design, novel materials synthesis, charge transport, defect tolerant materials, and scalable processing.

  11. Saving the Sun for a Rainy Day (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Bullock, R. Morris (Director, Center for Molecular Electrocatalysis); CME Staff

    2011-11-02T23:59:59.000Z

    'Saving the Sun for a Rainy Day' was submitted by the Center for Molecular Electrocatalysis (CME) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CME, an EFRC directed by R. Morris Bullock at Pacific Northwest National Laboratory is a partnership of scientists from four institutions: PNNL (lead), Pensylvania State University, University of Washington, and the University of Wyoming. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Molecular Electrocatalysis is 'to understand, design and develop molecular electrocatalysts for solar fuel production and use.' Research topics are: catalysis (water), electrocatalysis, bio-inspired, electrical energy storage, fuel cells, hydrogen (fuel), matter by design, novel materials synthesis, and charge transport.

  12. UNC EFRC: Fuels from Sunlight (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Meyer, Thomas J. (Director, UNC EFRC: Solar Fuels and Next Generation Photovoltaics); UNC EFRC Staff

    2011-11-02T23:59:59.000Z

    'Fuels from Sunlight' was submitted by the University of North Carolina (UNC) EFRC: Solar Fuels and Next Generation Photovoltaics to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. The UNC EFRC directed by Thomas J. Meyer is a partnership of scientists from six institutions: UNC (lead), Duke University, University of Florida, North Caroline Central University, North Carolina State University, and the Research Triangle Institute. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of Solar Fuels and Next Generation Photovoltaics is 'to combine the best features of academic and translational research to study light/matter interactions and chemical processes for the efficient collection, transfer, and conversion of solar energy into chemical fuels and electricity.' Research topics are: catalysis (CO{sub 2}, hydrocarbons, water), electrocatalysis, photocatalysis, photoelectrocatalysis, solar photovoltaic, solar fuels, photonic, solar electrodes, photosynthesis, fuel cells, CO{sub 2} (convert), greenhosue gas, hydrogen (fuel), interfacial characterization, novel materials synthesis, charge transport, and self-assembly.

  13. Enabling Energy Efficiency (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Coltrin, Mike (Acting Director, EFRC for Solid State Lighting Science); Simmons, Jerry; SSLS Staff

    2011-11-03T23:59:59.000Z

    'Enabling Energy Efficiency' was submitted by the EFRC for Solid-State Lighting Science (SSLS) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. SSLS is directed by Mike Coltrin (Acting) and Jerry Simmons at Sandia National Laboratories, and is a partnership of scientists from eight institutions: Sandia National Laboratories (lead); California Institute of Technology; Los Alamos National Laboratory; University of Massachusetts, Lowell; University of New Mexico; Northwestern University; Philips Lumileds Lighting; and Rensselaer Polytechnic Institute. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  14. Search for the ANSER (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum

    ScienceCinema (OSTI)

    Wasielewski, Michael R. (Director, Argonne-Northwestern Solar Energy Research Center); ANSER Staff

    2011-11-02T23:59:59.000Z

    'Search for the ANSER' was submitted by the Argonne-Northwestern Solar Energy Research Center (ANSER) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. ANSER, an EFRC directed by Michael Wasielewski at Argonne National Laboratory is a partnership of scientists from five institutions: Argonne National Laboratory, Northwestern University, University of Chicago, University of Illinois at Urbana-Champaign, and Yale. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. At ANSER, the mission is 'to revolutionize our understanding of molecules, materials and methods necessary to create dramatically more efficient technologies for solar fuels and electricity production.' Research topics are: catalysis (water), electrocatalysis, photocatalysis, photoelectrocatalysis, solar photovoltaic, solar fuels, solar electrodes, photosynthesis, transportation fuels, bio-inspired, spin dynamics, hydrogen (fuel), ultrafast physics, interfacial characterization, matter by design, novel materials synthesis, charge transport, and self-assembly.

  15. Inverse Design: Playing "Jeopardy" in Materials Science (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Alex Zunger (former Director, Center for Inverse Design); Tumas, Bill (Director, Center for Inverse Design); CID Staff

    2011-11-02T23:59:59.000Z

    'Inverse Design: Playing 'Jeopardy' in Materials Science' was submitted by the Center for Inverse Design (CID) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CID, an EFRC directed by Bill Tumas at the National Renewable Energy Laboratory is a partnership of scientists from five institutions: NREL (lead), Northwestern University, University of Colorado, Stanford University, and Oregon State University. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Inverse Design is 'to replace trial-and-error methods used in the development of materials for solar energy conversion with an inverse design approach powered by theory and computation.' Research topics are: solar photovoltaic, photonic, metamaterial, defects, spin dynamics, matter by design, novel materials synthesis, and defect tolerant materials.

  16. Liquid Sunshine to Fuel Your Car (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Cosgrove, Daniel (Director, Center for Lignocellulose Structure and Formation); CLSF Staff

    2011-11-02T23:59:59.000Z

    'Liquid Sunshine to Fuel Your Car' was submitted by the Center for Lignocellulose Structure and Formation (CLSF) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CLSF is directed by Daniel Cosgrove at Pennsylvania State University and is a partnership of scientists from three institutions: Penn State (lead), North Caroline State University, and Virginia Tech University. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Lignocellulose Structure and Formation is 'to dramatically increase our fundamental knowledge of the formation and physical interactions of bio-polymer networks in plant cell walls to provide a basis for improved methods for converting biomass into fuels.' Research topics are: biofuels (biomass), membrane, interfacial characterization, matter by design, and self-assembly.

  17. Precision monitoring of relative beam intensity for Mu2e

    SciTech Connect (OSTI)

    Evans, N.J.; Kopp, S.E.; /Texas U.; Prebys, E.; /Fermilab

    2011-04-01T23:59:59.000Z

    For future experiments at the intensity frontier, precise and accurate knowledge of beam time structure will be critical to understanding backgrounds. The proposed Mu2e experiment will utilize {approx}200 ns (FW) bunches of 3 x 10{sup 7} protons at 8 GeV with a bunch-to-bunch period of 1695 ns. The out-of-bunch beam must be suppressed by a factor of 10{sup -10} relative to in-bunch beam and continuously monitored. I propose a Cerenkov-based particle telescope to measure secondary production from beam interactions in a several tens of microns thick foil. Correlating timing information with beam passage will allow the determination of relative beam intensity to arbitrary precision given a sufficiently long integration time. The goal is to verify out-of-bunch extinction to the level 10{sup -6} in the span of several seconds. This will allow near real-time monitoring of the initial extinction of the beam resonantly extracted from Fermilabs Debuncher before a system of AC dipoles and collimators, which will provide the final extinction. The effect on beam emittance is minimal, allowing the necessary continuous measurement. I will present the detector design and some concerns about bunch growth during the resonant extraction.

  18. Solar Fuels and Next Generation Photovoltaics: The UNC-CH Energy Frontier Research Center

    SciTech Connect (OSTI)

    Meyer, Thomas J.; Papanikolas, John M.; Heyer, Catherine M.

    2011-01-01T23:59:59.000Z

    The UNC Energy Frontier Research Center: “Solar Fuels and Next Generation Photovoltaics” is funded by a $17.5 M grant from the US Department of Energy. Its mission is to conduct basic research that will enable a revolution in the collection and conversion of sunlight into storable solar fuels and electricity.

  19. SEPTEMBER 3, 2013 LASPE NEWSLETTER USC-CHEVRON FRONTIERS OF ENERGY RESOURCES SUMMER

    E-Print Network [OSTI]

    Shahabi, Cyrus

    solutions to genuine challenge questions, such as the estimation of business costs for hypotheticalSEPTEMBER 3, 2013 LASPE NEWSLETTER PAGE 22 USC-CHEVRON FRONTIERS OF ENERGY RESOURCES SUMMER CAMP CHALLENGES FUTURE ENERGY ENGINEERS This past June, 24 outstanding high school students and 2 science teachers

  20. Explore the Genetic Frontier: Biotechnology and Cotton-Texas' Biggest Crop

    E-Print Network [OSTI]

    Boecker, Steve; Edelman, Jaime; Gergini, Timm; Hawkins, Carole; Hinnant, Thomas; O'Neill, Kelli

    2002-09-18T23:59:59.000Z

    This publication is one of the Explore the Genetic Frontier series brochures that discuss the use of biotechnology to develop new varieties of plants for human needs. Texas is the No. 1 producer of cotton in the United States. This brochure...

  1. Frontiers in Contaminant Speciation and Reactivity in Terrestrial Environments: The Role of Synchrotron Radiation

    E-Print Network [OSTI]

    Sparks, Donald L.

    science. To delineate reaction mechanisms of contaminant reactions on soil minerals and in soils attenuation processes, speciation of metal(loid)s in heterogeneous soilslbiosolids/plants, and mineral/microbe/contaminant226 Frontiers in Contaminant Speciation and Reactivity in Terrestrial Environments: The Role

  2. TABLE OF CONTENTS A Combinatorial Explosion | Cross-Disciplinary Approach Bridges Gaps to New Frontiers 4

    E-Print Network [OSTI]

    Prodiæ, Aleksandar

    Gaps to New Frontiers 4 Bending Beams and Extending the Laws of Physics to Focus Electromagnetic Waves with Unparalleled Precision 6 Revolution Evolution On The Net | Harnessing Network Dynamics for a Better Tomorrow 8 with innovative research ideas and projects. This creative energy, in turn, benefits our undergraduate program

  3. Vision Statement for Plant Physiology Comparative Plant Genomics. Frontiers and Prospects

    E-Print Network [OSTI]

    Purugganan, Michael D.

    Vision Statement for Plant Physiology Comparative Plant Genomics. Frontiers and Prospects Ana L function and evolution at various levels of biological organiza- tion. The availability of whole-genome sequences as well as other genomic resources (e.g. microarray meth- ods, expressed sequence tag [EST

  4. Web Intelligence: New Frontiers of Exploration Yiyu (Y.Y.) Yao

    E-Print Network [OSTI]

    Yao, Yiyu

    Web Intelligence: New Frontiers of Exploration Yiyu (Y.Y.) Yao Department of Computer Science://www.cs.uregina.ca/yyao Abstract-- Web Intelligence (WI) deals with the scientific exploration of the new territories of the Web in the context of the Web, and goes beyond each of them. From several perspectives of the Web, we investigate

  5. Frontiers in Public Health Services and Systems Research Volume 1 | Number 1 Article 6

    E-Print Network [OSTI]

    Sadeh, Norman M.

    improvement plans. Since these activities are fundamental aspects of accreditation and health reformFrontiers in Public Health Services and Systems Research Volume 1 | Number 1 Article 6 4-17-2012 Patterns of Interaction Among Local Public Health Officials and the Adoption of Recommended Practices

  6. Where are the Frontiers of Energy Research in a Stormy World?

    E-Print Network [OSTI]

    Companies: The Baton Passes from US/Japan to China #12;1. Top 10 Solar Companies: The Baton Passes from USWhere are the Frontiers of Energy Research in a Stormy World? 1 #12;The March of Solar of its environment more than regular academic research Don't Happy, Be Worry #12;4 1. Top 10 Solar

  7. Proceedings of the Seventh Applied Diamond Conference/Third Frontier Carbon

    E-Print Network [OSTI]

    Tzeng, Yonhua

    Proceedings of the Seventh Applied Diamond Conference/Third Frontier Carbon Technology Joint Conference (ADC/FCT 2003) NASA/CP--2003-212319 August 2003 #12;The NASA STI Program Office . . . in Profile. · CONFERENCE PUBLICATION. Collected papers from scientific and technical conferences, symposia, seminars

  8. Fractally deforested landscape: Pattern and process in a tri-national Amazon frontier

    E-Print Network [OSTI]

    Fractally deforested landscape: Pattern and process in a tri-national Amazon frontier Jing Sun a 32611, USA Keywords: Amazon Deforestation Fractal analysis Fixed-grid scans Bottom-up plan Configuration of deforestation at a pixel level from 1986 to 2010 in the study region. The evolving pattern of development

  9. Frontiers: Research highlights 1946-1996 [50th Anniversary Edition. Argonne National Laboratory

    SciTech Connect (OSTI)

    NONE

    1996-12-31T23:59:59.000Z

    This special edition of 'Frontiers' commemorates Argonne National Laboratory's 50th anniversary of service to science and society. America's first national laboratory, Argonne has been in the forefront of U.S. scientific and technological research from its beginning. Past accomplishments, current research, and future plans are highlighted.

  10. Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy Science: A Talk by Carl Wieman

    SciTech Connect (OSTI)

    Wieman, Carl

    2008-08-30T23:59:59.000Z

    Carl Wieman presents a talk at Frontiers in Laser Cooling, Single-Molecule Biophysics and Energy Science, a scientific symposium honoring Steve Chu, director of Lawrence Berkeley National Laboratory and recipient of the 1997 Nobel Prize in Physics. The symposium was held August 30, 2008 in Berkeley.

  11. Duty-Cycling Buildings Aggressively: The Next Frontier in HVAC Control

    E-Print Network [OSTI]

    Simunic, Tajana

    Duty-Cycling Buildings Aggressively: The Next Frontier in HVAC Control Yuvraj Agarwal, Bharathan the dominant energy consumer is the HVAC system. Despite this fact, in most buildings the HVAC system is run sensing to guide the operation of a building HVAC system. We show how we can enable aggressive duty

  12. FRONTIERS ARTICLE Efficiency enhancement of copper contaminated radial pn junction solar cells

    E-Print Network [OSTI]

    Yang, Peidong

    energy represents one of the most important sustainable and renewable energy sources. The most common power from solar cells [1]. The reason is that crystalline silicon solar cell manufacturingFRONTIERS ARTICLE Efficiency enhancement of copper contaminated radial p­n junction solar cells

  13. Frontier orbital symmetry control of intermolecular electron transfer. Final report, September 15, 1988--December 31, 1994

    SciTech Connect (OSTI)

    Stevens, B.

    1997-07-01T23:59:59.000Z

    This report discusses the following topics: the recovery of intermolecular transfer parameters from fluorescence quenching in liquids; photoinduced intramolecular electron transfer in flexible donor/space/acceptor systems containing an extended unsaturated spacer; electron transfer sensitized reaction; the recovery of solute and fractal dimensions from electron transfer quenching data; and frontier orbital symmetry control of back electron transfer.

  14. Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy Science: A Talk by Carl Wieman

    ScienceCinema (OSTI)

    Wieman, Carl

    2011-04-13T23:59:59.000Z

    Carl Wieman presents a talk at Frontiers in Laser Cooling, Single-Molecule Biophysics and Energy Science, a scientific symposium honoring Steve Chu, director of Lawrence Berkeley National Laboratory and recipient of the 1997 Nobel Prize in Physics. The symposium was held August 30, 2008 in Berkeley.

  15. The Cosmic Web: Geometric Analysis

    E-Print Network [OSTI]

    Rien van de Weygaert; Willem Schaap

    2007-08-10T23:59:59.000Z

    The lecture notes describe the Delaunay Tessellation Field Estimator for Cosmic Web analysis. The high sensitivity of Voronoi/Delaunay tessellations to the local point distribution is used to obtain estimates of density and related quantities. The adaptive and minimum triangulation properties of Delaunay tessellations are utilized for interpolation to continuous volume-covering density and velocity fields. The adaptivity to the local density and geometry preserves three key characteristics of the cosmic matter distribution: 1) its hierarchical nature,2) its anisotropic weblike morphology, 3) the presence and structure of voids. The lecture notes discuss the mathematical context and background of the DTFE method, in essence a first order version of Natural Neighbour methods, smooth and higher order spatial interpolation techniques. This is followed by an outline of the DTFE procedure. A series of tests on spatially complex point distributions provides quantitative information on its performance and noise characteristics. We conclude with a few cosmological applications. The reconstruction of the spatial weblike patterns in N-body simulations and in the 2dFGRS provide a visual impression of DTFE's performance. The analysis of the velocity divergence pdf and maps obtained of the velocity flow in the Local Universe (implied by PSCz) illustrate its promise for probing the dynamics of cosmic structure. The Watershed Void Finder (Platen et al. 2007), for the study of voids, and Multiscale Morphology Filter (Aragon-Calvo et al. 2007), for identifying and analyzing weblike networks of filaments, sheets and clusters, are based upon DTFE density fields. We also mention SimpleX, a related random lattice radiative transfer formalism (Ritzerveld & Icke 2006).

  16. A Cosmic Vision Beyond Einstein

    E-Print Network [OSTI]

    Eric V. Linder

    2008-10-09T23:59:59.000Z

    The acceleration of the cosmic expansion is a fundamental challenge to standard models of particle physics and cosmology. The new physics of dark energy may lie in the nature of gravity, the quantum vacuum, or extra dimensions. I give a brief overview of the puzzles and possibilities of dark energy, and discuss the confrontation of a wide variety of "beyond Einstein" models with the latest data, showing what we currently know and what we must seek to learn. Next generation experiments using a variety of cosmological probes will deeply explore dark energy, dark matter, and gravitation.

  17. The cosmic variance of Omega

    E-Print Network [OSTI]

    T. P. Waterhouse; J. P. Zibin

    2008-04-10T23:59:59.000Z

    How much can we know about our Universe? All of our observations are restricted to a finite volume, and therefore our estimates of presumably global cosmological parameters are necessarily based on incomplete information. Even assuming that the Standard Model of cosmology is correct, this means that some cosmological questions may be unanswerable. For example, is the curvature parameter Omega_K positive, negative, or identically zero? If its magnitude is sufficiently small, then due to cosmic variance no causal observation can ever answer that question. In this article, we first describe the gauge problems associated with defining the cosmic variance of cosmological parameters, then describe a solution involving the use of parameters defined on the surface of last scattering, and finally calculate the statistical variance of ideal measurements of the matter, radiation, and curvature density parameters. We find that Omega_K cannot be measured to better than about 1.5x10^(-5) (1 sigma), and that this limit has already begun to decrease due to the flattening effect of dark energy. Proposed 21 cm hydrogen experiments, for example, make this limit more than just a theoretical curiosity.

  18. Cosmic radioactivity and INTEGRAL results

    SciTech Connect (OSTI)

    Diehl, Roland [Max Planck Institut für Extraterrestrische Physik, D-85748 Garching, Germany and Excellence Cluster Origin and Evolution of the Universe', D-85748 Garching (Germany)

    2014-05-02T23:59:59.000Z

    Gamma-ray lines from radioactive decay of unstable isotopes co-produced by nucleosynthesis in massive stars and supernova have been measured since more than thirty years. Over the past ten years, INTEGRAL complemented the first sky survey made by COMPTEL. The {sup 26}A1 isotope with 1 My decay time had been first direct proof of currently-ongoing nucleosynthesis in our Galaxy. This has now become a tool to study the ?My history of specific source regions, such as massive-star groups and associations in nearby regions which can be discriminated from the galactic-plane background, and the inner Galaxy, where Doppler shifted lines add to the astronomical information about bar and spiral structure. Recent findings suggest that superbubbles show a remarkable asymmetry, on average, in the spiral arms of our galaxy. {sup 60}Fe is co-produced by the sources of {sup 26}A1, and the isotopic ratio from their nucleosynthesis encodes stellar-structure information. Annihilation gamma-rays from positrons in interstellar space show a puzzling bright and extended source region central to our Galaxy, but also may be partly related to nucleosynthesis. {sup 56}Ni and {sup 44}Ti isotope gamma-rays have been used to constrain supernova explosion mechanisms. Here we report latest results using the accumulated multi-year database of INTEGRAL observations, and discuss their astrophysical interpretations, connecting to other traces of cosmic radioactivity and to other cosmic messengers.

  19. Frontiers for Discovery in High Energy Density Physics

    SciTech Connect (OSTI)

    Davidson, R. C.; Katsouleas, T.; Arons, J.; Baring, M.; Deeney, C.; Di Mauro, L.; Ditmire, T.; Falcone, R.; Hammer, D.; Hill, W.; Jacak, B.; Joshi, C.; Lamb, F.; Lee, R.; Logan, B. G.; Melissinos, A.; Meyerhofer, D.; Mori, W.; Murnane, M.; Remington, B.; Rosner, R.; Schneider, D.; Silvera, I.; Stone, J.; Wilde, B.; Zajc. W.

    2004-07-20T23:59:59.000Z

    The report is intended to identify the compelling research opportunities of high intellectual value in high energy density physics. The opportunities for discovery include the broad scope of this highly interdisciplinary field that spans a wide range of physics areas including plasma physics, laser and particle beam physics, nuclear physics, astrophysics, atomic and molecular physics, materials science and condensed matter physics, intense radiation-matter interaction physics, fluid dynamics, and magnetohydrodynamics

  20. EMMA an underground cosmic-ray experiment T. Enqvista

    E-Print Network [OSTI]

    Usoskin, Ilya G.

    of Oulu, Oulu, Finland g Radiation and Nuclear Safety Authority (STUK), Helsinki, Finland A new cosmic

  1. OBSERVATION OF ANISOTROPY IN THE ARRIVAL DIRECTIONS OF GALACTIC COSMIC RAYS AT MULTIPLE ANGULAR SCALES WITH IceCube

    SciTech Connect (OSTI)

    Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium); Abu-Zayyad, T. [Department of Physics, University of Wisconsin, River Falls, WI 54022 (United States); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Ahlers, M. [Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Altmann, D. [III. Physikalisches Institut, RWTH Aachen University, D-52056 Aachen (Germany); Auffenberg, J.; Becker, K.-H. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Alba, J. L. Bazo; Benabderrahmane, M. L. [DESY, D-15735 Zeuthen (Germany); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Universite Libre de Bruxelles, Science Faculty CP230, B-1050 Brussels (Belgium); Becker, J. K. [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

    2011-10-10T23:59:59.000Z

    Between 2009 May and 2010 May, the IceCube neutrino detector at the South Pole recorded 32 billion muons generated in air showers produced by cosmic rays with a median energy of 20 TeV. With a data set of this size, it is possible to probe the southern sky for per-mil anisotropy on all angular scales in the arrival direction distribution of cosmic rays. Applying a power spectrum analysis to the relative intensity map of the cosmic ray flux in the southern hemisphere, we show that the arrival direction distribution is not isotropic, but shows significant structure on several angular scales. In addition to previously reported large-scale structure in the form of a strong dipole and quadrupole, the data show small-scale structure on scales between 15{sup 0} and 30{sup 0}. The skymap exhibits several localized regions of significant excess and deficit in cosmic ray intensity. The relative intensity of the smaller-scale structures is about a factor of five weaker than that of the dipole and quadrupole structure. The most significant structure, an excess localized at (right ascension {alpha} = 122.{sup 0}4 and declination {delta} = -47.{sup 0}4), extends over at least 20{sup 0} in right ascension and has a post-trials significance of 5.3{sigma}. The origin of this anisotropy is still unknown.

  2. Carbon in Underland (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum

    ScienceCinema (OSTI)

    DePaolo, Donald J. (Director, Center for Nanoscale Control of Geologic CO2); NCGC Staff

    2011-11-02T23:59:59.000Z

    'Carbon in Underland' was submitted by the Center for Nanoscale Control of Geologic CO2 (NCGC) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. This video was selected as one of five winners by a distinguished panel of judges for its 'entertaining animation and engaging explanations of carbon sequestration'. NCGC, an EFRC directed by Donald J. DePaolo at Lawrence Berkeley National Laboratory is a partnership of scientists from seven institutions: LBNL (lead) Massachusetts Institute of Technology, Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, University of California, Davis, Ohio State University, and Washington University in St. Louis. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Nanoscale Control of Geologic CO{sub 2} is 'to use new investigative tools, combined with experiments and computer simulations, to build a fundamental understanding of molecular-to-pore-scale processes in fluid-rock systems, and to demonstrate the ability to control critical aspects of flow, transport, and mineralization in porous rock media as applied to geologic sequestration of CO{sub 2}. Research topics are: bio-inspired, CO{sub 2} (store), greenhouse gas, and interfacial characterization.

  3. New Dimensions in Cosmic Lensing

    E-Print Network [OSTI]

    Andy Taylor

    2003-06-13T23:59:59.000Z

    I review the current status of combing weak gravitational lensing with depth information from redshifts as a direct probe of dark matter and dark energy in the Universe. In particular I highlight: (1) The first maximum likelihood measurement of the cosmic shear power spectrum, with the COMBO17 dataset (Brown et al 2003); (2) A new method for mapping the 3-D dark matter distribution from weak shear, and its first application to the COMBO17 dataset (Taylor et al 2003); (3) A new method for measuring the Dark Energy of the Universe using purely the geometry of gravitational lensing, based on cross-correlation tomography (Jain & Taylor 2003). I show that this method can constrain the equation of state of the universe and its evolution to a few percent accuracy.

  4. Ultra High Energy Cosmic Rays

    E-Print Network [OSTI]

    Todor Stanev

    2004-11-04T23:59:59.000Z

    We discuss theoretical issues and experimental data that brought the ultra high energy cosmic rays in the list of Nature's greatest puzzles. After many years of research we still do not know how astrophysical acceleration processes can reach energies exceeding 10$^{11}$ GeV. The main alternative {\\em top-down} mechanism postulates the existence of super massive $X$-particles that create a particle spectrum extending down to the observed energy through their decay channels. The propagation of nuclei and photons from their sources to us adds to the puzzle as all particles of these energies interact with the ambient photons, mostly of the microwave background. We also describe briefly the main observational results and give some information on the new experiments that are being built and designed now.

  5. SLAC Cosmic Ray Telescope Facility

    SciTech Connect (OSTI)

    Va'vra, J.

    2010-02-15T23:59:59.000Z

    SLAC does not have a test beam for the HEP detector development at present. We have therefore created a cosmic ray telescope (CRT) facility, which is presently being used to test the FDIRC prototype. We have used it in the past to debug this prototype with the original SLAC electronics before going to the ESA test beam. Presently, it is used to test a new waveform digitizing electronics developed by the University of Hawaii, and we are also planning to incorporate the new Orsay TDC/ADC electronics. As a next step, we plan to put in a full size DIRC bar box with a new focusing optics, and test it together with a final SuberB electronics. The CRT is located in building 121 at SLAC. We anticipate more users to join in the future. This purpose of this note is to provide an introductory manual for newcomers.

  6. Fermilab | Science at Fermilab | Experiments & Projects | Energy Frontier

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13, 2013Focusreceives .1Grid Intensity

  7. Fermilab | Science at Fermilab | Experiments & Projects | Energy Frontier |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13, 2013Focusreceives .1Grid IntensityFermilab and

  8. Evidences of high energy protons with energies beyond 0.4 GeV in the solar particle spectrum as responsible for the cosmic rays solar diurnal anisotropy

    E-Print Network [OSTI]

    C. E. Navia; C. R. A. Augusto; M. B. Robba; K. H. Tsui

    2007-06-26T23:59:59.000Z

    Analysis on the daily variations of cosmic ray muons with $E_{\\mu}\\geq 0.2 GeV$ based on the data of two directional muon telescopes at sea level and with a rigidity of response to cosmic proton spectrum above 0.4 GV is presented. The analysis covers two months of observations and in 60% of days, abrupt transitions between a low to a high muon intensity and vice-verse is observed, the period of high muon intensity is from $\\sim 8.0h$ up to $\\sim 19.0h$ (local time) and coincides with the period when the interplanetary magnetic field (IMF) lines overtake the Earth. This behavior strongly suggest that the high muon intensity is due to a contribution of solar protons (ions) on the muon intensity produced by the galactic cosmic rays, responsible for the low muon intensity. This implies that the solar particle spectrum extends to energies beyond 1 GeV. We show that this picture can explain the solar daily variation origin, and it is a most accurate scenario than the assumption of corotating galactic cosmic ray with the IMF lines, specially in the high rigidity region. Obtained results are consistent with the data reported in others papers. Some aspects on the sensitivity of our muon telescopes are also presented.

  9. Effect of cosmic string on spin dynamics

    E-Print Network [OSTI]

    Debashree Chowdhury; B. Basu

    2014-11-07T23:59:59.000Z

    In the present paper, we have investigated the role of cosmic string on spin current and Hall electric field. Due to the background cosmic string, the modified electric field of the system generates renormalized spin orbit coupling, which induces a modified non-Abelian gauge field. The defect causes a change in the AB and AC phases appearing due to the modified electromagnetic field. In addition, for a time varying electric field we perform explicit analytic calculations to derive the exact form of spin electric field and spin current, which is defect parameter dependent and of oscillating type. Furthermore, in an asymmetric crystal within the Drude model approach we investigate the dependence of the cosmic string parameters on cosmic string induced Hall electric field.

  10. COSMIC-RAY TRANSPORT AND ANISOTROPIES

    SciTech Connect (OSTI)

    Biermann, Peter L. [MPI for Radioastronomy, Auf dem Huegel 69, D-53121 Bonn (Germany); Becker Tjus, Julia; Mandelartz, Matthias [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Theoretische Physik I, D-44780 Bochum (Germany); Seo, Eun-Suk [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

    2013-05-10T23:59:59.000Z

    We show that the large-scale cosmic-ray anisotropy at {approx}10 TeV can be explained by a modified Compton-Getting effect in the magnetized flow field of old supernova remnants. Cosmic rays arrive isotropically to the flow field and are then carried along with the flow to produce a large-scale anisotropy in the arrival direction. This approach suggests an optimum energy scale for detecting the anisotropy. Two key assumptions are that propagation is based on turbulence following a Kolmogorov law and that cosmic-ray interactions are dominated by transport via cosmic-ray-excited magnetic irregularities through the stellar wind of an exploding star and its shock shell. A prediction is that the amplitude is smaller at lower energies due to incomplete sampling of the velocity field and also smaller at larger energies due to smearing.

  11. Terrestrial Effects of High Energy Cosmic Rays

    E-Print Network [OSTI]

    Atri, Dimitra

    2011-04-26T23:59:59.000Z

    On geological timescales, the Earth is likely to be exposed to higher than the usual flux of high energy cosmic rays (HECRs) from astrophysical sources such as nearby supernovae, gamma ray bursts or by galactic shocks. ...

  12. Detecting cosmic rays of the highest energies

    E-Print Network [OSTI]

    F. Vannucci

    2001-06-06T23:59:59.000Z

    Charged cosmic rays have been measured up to macroscopic energies. Concerning neutrinos, the detection is still limited to terrestrial ones (apart from supernova production). A new way to search for extragalactic neutrinos is discussed.

  13. Annual modulation of cosmic relic neutrinos

    E-Print Network [OSTI]

    Safdi, Benjamin R.

    The cosmic neutrino background (C?B), produced about one second after the big bang, permeates the Universe today. New technological advancements make neutrino capture on beta-decaying nuclei (NCB) a clear path forward ...

  14. Cosmic neutrino cascades from secret neutrino interactions

    E-Print Network [OSTI]

    Kenny C. Y. Ng; John F. Beacom

    2014-11-01T23:59:59.000Z

    The first detection of high-energy astrophysical neutrinos by IceCube provides new opportunities for tests of neutrino properties. The long baseline through the Cosmic Neutrino Background (C$\

  15. The highest-energy cosmic rays

    E-Print Network [OSTI]

    James W. Cronin

    2004-02-20T23:59:59.000Z

    This paper begins with a pedagogical discussion of the propagation of cosmic rays and the showers produced when a cosmic ray primary hits the upper atmosphere. The paper focusses cosmic rays, with energy > 10^19 eV. Emphasis is placed on the shower properties that are relevant to the detection of cosmic rays by surface arrays and fluorescence telescopes. The two major experiments, AGASA and HiRes are described in some detail. Then the experimental results are reviewed. It is no surprise that more data will be needed. But it is also true that improved analysis and further data from HiRes can make significant improvements in the experimental situation.

  16. Essays on Regression Spline Structural Nonparametric Stochastic Production Frontier Estimation and Inefficiency Analysis Models

    E-Print Network [OSTI]

    Li, Ke

    2012-02-14T23:59:59.000Z

    of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2010 Major Subject: Agricultural Economics Essays on Regression Spline Structural Nonparametric Stochastic Production Frontier Estimation and Ine ciency Analysis Models Copyright 2010 Ke Li... of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Ximing Wu Committee Members, David Bessler H. Alan Love Qi Li Head of Department, John P. Nichols December 2010 Major Subject: Agricultural Economics iii ABSTRACT...

  17. School Cosmic Ray Outreach Detector (SCROD)

    E-Print Network [OSTI]

    L. A. Anchordoqui; J. Cook; M. Gabour; N. Kirsch; J. MacLeod; T. P. McCauley; Y. Musienko; T. C. Paul; S. Reucroft; J. D. Swain; R. Terry

    2001-06-01T23:59:59.000Z

    We report on our studies of applying novel detector technologies developed for LHC-era experiments to cosmic ray detection. In particular, we are investigating usage of scintillating tiles with embedded wavelength-shifting fibers and avalanche photodiode readout as part of a robust, inexpensive cosmic air shower detector. In the near future, we are planning to deploy detector stations based on this technology at area high schools and colleges as part of an outreach and education effort, known as SCROD.

  18. Gamma Ray Bursts from Ordinary Cosmic Strings

    E-Print Network [OSTI]

    R. H. Brandenberger; A. T. Sornborger; M. Trodden

    1993-02-12T23:59:59.000Z

    We give an upper estimate for the number of gamma ray bursts from ordinary (non-superconducting) cosmic strings expected to be observed at terrestrial detectors. Assuming that cusp annihilation is the mechanism responsible for the bursts we consider strings arising at a GUT phase transition and compare our estimate with the recent BATSE results. Further we give a lower limit for the effective area of future detectors designed to detect the cosmic string induced flux of gamma ray bursts.

  19. MCNP6 Cosmic-Source Option

    SciTech Connect (OSTI)

    McKinney, Gregg W [Los Alamos National Laboratory; Armstrong, Hirotatsu [Los Alamos National Laboratory; James, Michael R [Los Alamos National Laboratory; Clem, John [University of Delaware, BRI; Goldhagen, Paul [DHS, National Urban Security Technology Laboratory

    2012-06-19T23:59:59.000Z

    MCNP is a Monte Carlo radiation transport code that has been under development for over half a century. Over the last decade, the development team of a high-energy offshoot of MCNP, called MCNPX, has implemented several physics and algorithm improvements important for modeling galactic cosmic-ray (GCR) interactions with matter. In this presentation, we discuss the latest of these improvements, a new Cosmic-Source option, that has been implemented in MCNP6.

  20. Greatly improved cache update times for conditions data with Frontier/Squid

    SciTech Connect (OSTI)

    Dykstra, Dave; Lueking, Lee; /Fermilab

    2009-05-01T23:59:59.000Z

    The CMS detector project loads copies of conditions data to over 100,000 computer cores worldwide by using a software subsystem called Frontier. This subsystem translates database queries into HTTP, looks up the results in a central database at CERN, and caches the results in an industry-standard HTTP proxy/caching server called Squid. One of the most challenging aspects of any cache system is coherency, that is, ensuring that changes made to the underlying data get propagated out to all clients in a timely manner. Recently, the Frontier system was enhanced to drastically reduce the time for changes to be propagated everywhere without heavily loading servers. The propagation time is now as low as 15 minutes for some kinds of data and no more than 60 minutes for the rest of the data. This was accomplished by taking advantage of an HTTP and Squid feature called If-Modified-Since. In order to use this feature, the Frontier server sends a Last-Modified timestamp, but since modification times are not normally tracked by Oracle databases, a PL/SQL program was developed to track the modification times of database tables. We discuss the details of this caching scheme and the obstacles overcome including database and Squid bugs.

  1. Cosmic Rays, Gamma-Rays, & Neutrinos in the Starburst Nuclei of Arp 220

    E-Print Network [OSTI]

    Yoast-Hull, Tova M; Zweibel, Ellen G

    2015-01-01T23:59:59.000Z

    The cores of Arp 220, the closest ultra-luminous infrared starburst galaxy, provide an opportunity to study interactions of cosmic rays under extreme conditions. In this paper, we model the populations of cosmic rays produced by supernovae in the central molecular zones of both starburst nuclei. We find that ~65 - 100% of cosmic rays are absorbed in these regions due to their huge molecular gas contents, and thus, the nuclei of Arp 220 nearly complete proton calorimeters. As the cosmic ray protons collide with the interstellar medium, they produce secondary electrons that are also contained within the system and radiate synchrotron emission. Using results from chi-squared tests between the model and the observed radio spectral energy distribution, we predict the emergent gamma-ray and high-energy neutrino spectra and find the magnetic field to be at milligauss levels. Because of the extremely intense far-infrared radiation fields, the gamma-ray spectrum steepens significantly at TeV energies due to gamma-gamm...

  2. High-energy cosmic neutrinos from spine-sheath BL Lac jets

    E-Print Network [OSTI]

    Tavecchio, F

    2014-01-01T23:59:59.000Z

    We recently proposed that structured (spine-sheath) jets associated to BL Lac objects offer a suitable environment for the production of the extragalactic high-energy ($E>100$ TeV) neutrino recently revealed by IceCube. Our previous analysis was limited to low-power BL Lac objects. We extend our preliminary study to the entire BL Lac population. We assume that the power of cosmic rays as well as the radiative luminosity of the sheath depend linearly on the the jet power. In turn, we assume that the latter is well traced by the $\\gamma$-ray luminosity. We exploit the BL Lac $\\gamma$-ray luminosity function and its cosmic evolution as recently inferred from Fermi-LAT data to derive the expected neutrino cumulative intensity from the entire BL Lac population. When considering only the low-power BL Lacs, a large cosmic ray power for each source is required to account for the neutrino flux. Instead, if BL Lacs of all powers produce neutrinos, the power demand decreases, and the required cosmic ray power becomes of...

  3. High-Energy Neutrinos from Cosmic Rays

    E-Print Network [OSTI]

    F. Halzen

    2002-06-17T23:59:59.000Z

    We introduce neutrino astronomy from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back close to a century, we do not know how and where they are accelerated. We review the facts as well as the speculations about the sources. Among these gamma ray bursts and active galaxies represent well-motivated speculations because these are also the sources of the highest energy gamma rays, with emission observed up to 20 TeV, possibly higher. We discuss why cosmic accelerators are also expected to be cosmic beam dumps producing high-energy neutrino beams associated with the highest energy cosmic rays. Cosmic ray sources may produce neutrinos from MeV to EeV energy by a variety of mechanisms. The important conclusion is that, independently of the specific blueprint of the source, it takes a kilometer-scale neutrino observatory to detect the neutrino beam associated with the highest energy cosmic rays and gamma rays. The technology for commissioning such instruments exists.

  4. Neutrino Physics from the Cosmic Microwave Background and Large Scale Structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Slosar, A.; Arnold, K.; Austermann, J.; Benson, B. A.; Bischoff, C.; Bock, J.; Bond, J. R.; Borrill, J.; Calabrese, E.; Carlstrom, J. E.; Carvalho, C. S.; Chang, C. L.; Chiang, H. C.; Church, S.; Cooray, A.; Crawford, T. M.; Dawson, K. S.; Das, S.; Devlin, M. J.; Dobbs, M.; Dodelson, S.; Dore, O.; Dunkley, J.; Errard, J.; Fraisse, A.; Gallicchio, J.; Halverson, N. W.; Hanany, S.; Hildebrandt, S. R.; Hincks, A.; Hlozek, R.; Holder, G.; Holzapfel, W. L.; Honscheid, K.; Hu, W.; Hubmayr, J.; Irwin, K.; Jones, W. C.; Kamionkowski, M.; Keating, B.; Keisler, R.; Knox, L.; Komatsu, E.; Kovac, J.; Lawrence, C.; Lee, A. T.; Leitch, E.; Linder, E.; Lubin, P.; McMahon, J.; Miller, A.; Newburgh, L.; Niemack, M. D.; Nguyen, H.; Nguyen, H. T.; Page, L.; Pryke, C.; Reichardt, C. L.; Ruhl, J. E.; Sehgal, N.; Seljak, U.; Sievers, J.; Silverstein, E.; Smith, K. M.; Spergel, D.; Staggs, S. T.; Stark, A.; Stompor, R.; Vieregg, A. G.; Wang, G.; Watson, S.; Wollack, E. J.; Wu, W. L.K.; Yoon, K. W.; Zahn, O.; Kuo, C. -L.

    2015-03-01T23:59:59.000Z

    This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in detail via its influence on distance-redshift relations and the growth of structure. The program for the next decade described in this document, including upcoming spectroscopic galaxy surveys eBOSS and DESI and a new Stage-IV CMB polarization experiment CMB-S4, will achieve ? (?mv) = 16 meV and ? (Neff)(Neff) = 0.020. Such a mass measurement will produce a high significance detection of non-zero ?m??m?, whose lower bound derived from atmospheric and solar neutrino oscillation data is about 58 meV. If neutrinos have a minimal normal mass hierarchy, this measurement will definitively rule out the inverted neutrino mass hierarchy, shedding light on one of the most puzzling aspects of the Standard Model of particle physics — the origin of mass. This precise a measurement of Neff will allow for high sensitivity to any light and dark degrees of freedom produced in the big bang and a precision test of the standard cosmological model prediction that Neff = 3.046.

  5. Neutrino Physics from the Cosmic Microwave Background and Large Scale Structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Slosar, A.; Arnold, K.; Austermann, J.; Benson, B. A.; Bischoff, C.; Bock, J.; Bond, J. R.; Borrill, J.; Calabrese, E.; Carlstrom, J. E.; et al

    2015-03-01T23:59:59.000Z

    This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in detail via its influence on distance-redshift relations and the growth of structure. The program for the next decade described in this document, including upcoming spectroscopic galaxy surveys eBOSS and DESI and a new Stage-IV CMB polarization experiment CMB-S4, will achieve ? (?mv) = 16 meV and ? (Neff)(Neff) = 0.020.more »Such a mass measurement will produce a high significance detection of non-zero ?m??m?, whose lower bound derived from atmospheric and solar neutrino oscillation data is about 58 meV. If neutrinos have a minimal normal mass hierarchy, this measurement will definitively rule out the inverted neutrino mass hierarchy, shedding light on one of the most puzzling aspects of the Standard Model of particle physics — the origin of mass. This precise a measurement of Neff will allow for high sensitivity to any light and dark degrees of freedom produced in the big bang and a precision test of the standard cosmological model prediction that Neff = 3.046.« less

  6. Energy conditions and cosmic acceleration

    SciTech Connect (OSTI)

    Santos, J. [Universidade Federal do Rio Grande do Norte, Departamento de Fisica, C.P. 1641, 59072-970 Natal, RN (Brazil); Departamento de Astronomia, Observatorio Nacional, 20921-400, Rio de Janeiro, RJ (Brazil); Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil); Alcaniz, J. S. [Departamento de Astronomia, Observatorio Nacional, 20921-400, Rio de Janeiro, RJ (Brazil); Pires, N. [Universidade Federal do Rio Grande do Norte, Departamento de Fisica, C.P. 1641, 59072-970 Natal, RN (Brazil); Reboucas, M. J. [Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil)

    2007-04-15T23:59:59.000Z

    In general relativity, the energy conditions are invoked to restrict general energy-momentum tensors T{sub {mu}}{sub {nu}} in different frameworks, and to derive general results that hold in a variety of general contexts on physical grounds. We show that in the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) approach, where the equation of state of the cosmological fluid is unknown, the energy conditions provide model-independent bounds on the behavior of the distance modulus of cosmic sources as a function of the redshift for any spatial curvature. We use the most recent type Ia supernovae (SNe Ia) observations, which include the new Hubble Space Telescope SNe Ia events, to carry out a model-independent analysis of the energy conditions violation in the context of the standard cosmology. We show that both the null (NEC), weak (WEC), and dominant (DEC) conditions, which are associated with the existence of the so-called phantom fields, seem to have been violated only recently (z < or approx. 0.2), whereas the condition for attractive gravity, i.e., the strong energy condition (SEC) was first violated billions of years ago, at z > or approx. 1.

  7. The Behavior of Hydrogen Under Extreme Conditions on Ultrafast Timescales (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Mao, Ho-kwang (Director, Center for Energy Frontier Research in Extreme Environments); EFree Staff

    2011-11-02T23:59:59.000Z

    'The Behavior of Hydrogen Under Extreme Conditions on Ultrafast Timescales ' was submitted by the Center for Energy Frontier Research in Extreme Environments (EFree) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. EFree is directed by Ho-kwang Mao at the Carnegie Institute of Washington and is a partnership of scientists from thirteen institutions.The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of Energy Frontier Research in Extreme Environments is 'to accelerate the discovery and creation of energy-relevant materials using extreme pressures and temperatures.' Research topics are: catalysis (CO{sub 2}, water), photocatalysis, solid state lighting, optics, thermelectric, phonons, thermal conductivity, solar electrodes, fuel cells, superconductivity, extreme environment, radiation effects, defects, spin dynamics, CO{sub 2} (capture, convert, store), greenhouse gas, hydrogen (fuel, storage), ultrafast physics, novel materials synthesis, and defect tolerant materials.

  8. Development of large flow counters for detection of low intensity cosmic ray particles

    E-Print Network [OSTI]

    Bull, Kenneth Winson

    1965-01-01T23:59:59.000Z

    the fluorescent tubing for use as Geiger envelopes, one must use extreme care. The white coating contains beryllium zinc silicate which is toxic if brought into contact with the mucous membranes. The glass is also very brittle and therefore gloves should... be obtained in various sizes and is strong, unifozm in cross section, and smooth. It has the disadvantage, however, that it cannot be soft soldezed. For this reason, the tungsten is first spot welded to some nickel-silver wire at each end. Then the nickel...

  9. OBSERVATION OF ANISOTROPY IN THE GALACTIC COSMIC-RAY ARRIVAL DIRECTIONS AT 400 TeV WITH ICECUBE

    SciTech Connect (OSTI)

    Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium); Abu-Zayyad, T. [Department of Physics, University of Wisconsin, River Falls, WI 54022 (United States); Ackermann, M.; Bazo Alba, J. L. [DESY, D-15735 Zeuthen (Germany); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Ahlers, M. [Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Allen, M. M. [Department of Physics, Pennsylvania State University, University Park, PA 16802 (United States); Altmann, D. [III. Physikalisches Institut, RWTH Aachen University, D-52056 Aachen (Germany); Auffenberg, J. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Science Faculty CP230, Universite Libre de Bruxelles, B-1050 Brussels (Belgium); Becker, J. K. [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Collaboration: IceCube Collaboration; and others

    2012-02-10T23:59:59.000Z

    In this paper we report the first observation in the Southern hemisphere of an energy dependence in the Galactic cosmic-ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic-ray-induced muons recorded by the partially deployed IceCube observatory between 2009 May and 2010 May. The data include a total of 33 Multiplication-Sign 10{sup 9} muon events with a median angular resolution of {approx}3 Degree-Sign . A sky map of the relative intensity in arrival direction over the Southern celestial sky is presented for cosmic-ray median energies of 20 and 400 TeV. The same large-scale anisotropy observed at median energies around 20 TeV is not present at 400 TeV. Instead, the high-energy sky map shows a different anisotropy structure including a deficit with a post-trial significance of -6.3{sigma}. This anisotropy reveals a new feature of the Galactic cosmic-ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.

  10. Monopole Annihilation and Highest Energy Cosmic Rays

    E-Print Network [OSTI]

    P. Bhattacharjee; G. Sigl

    1994-12-15T23:59:59.000Z

    Cosmic rays with energies exceeding $10^{20}\\eV$ have been detected. The origin of these highest energy cosmic rays remains unknown. Established astrophysical acceleration mechanisms encounter severe difficulties in accelerating particles to these energies. Alternative scenarios where these particles are created by the decay of cosmic topological defects have been suggested in literature. In this paper we study the possibility of producing the highest energy cosmic rays through a process that involves formation of metastable magnetic monopole-antimonopole bound states and their subsequent collapse. The annihilation of the heavy monopole-antimonopole pairs constituting the monopolonia can produce energetic nucleons, gamma rays and neutrinos whose expected flux we estimate and discuss in relation to experimental data so far available. The monopoles we consider are the ones that could be produced in the early universe during a phase transition at the grand unification energy scale. We find that observable cosmic ray fluxes can be produced with monopole abundances compatible with present bounds.

  11. Cosmic Ray Interactions in Shielding Materials

    SciTech Connect (OSTI)

    Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J.; Troy, Meredith D.

    2011-09-08T23:59:59.000Z

    This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earth’s surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that will stop the induced neutrons. The interaction of the different cosmic-ray components at ground level (protons, neutrons, muons) with their wide energy range (from kilo-electron volts to giga-electron volts) is a complex calculation. Monte Carlo calculations have proven to be a suitable tool for the simulation of nucleon transport, including hadron interactions and radioactive isotope production. The industry standard Monte Carlo simulation tool, Geant4, was used for this study. The result of this study is the assertion that activation at Earth’s surface is a result of the neutronic and protonic components of the cosmic-ray shower. The best material to shield against these cosmic-ray components is iron, which has the best combination of primary shielding and minimal secondary neutron production.

  12. ITP Energy Intensive Processes: Energy-Intensive Processes Portfolio...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    teChnologIes Program IntroduCtIon the research and development (r&d) portfolio for energy-Intensive Processes (eIP) addresses the top technology opportunities to save energy...

  13. Reference Radiation for Cosmic Rays in RBE Research 

    E-Print Network [OSTI]

    Feng, Shaoyong

    2011-10-21T23:59:59.000Z

    When astronauts travel in space, they are exposed to high energy cosmic radiations. The cosmic ray spectrum contains very high energy particles, generally up to several GeV per nucleon. Currently NASA is funding research on the effects...

  14. Intensity-Intensity Correlations of Classically Entangled Light

    E-Print Network [OSTI]

    Partha Ghose; Anirban Mukherjee

    2014-01-03T23:59:59.000Z

    An experiment is proposed to show that after initial frequency and polarization selection, classical thermal light from two independent sources can be made path-polarization entangled. Such light will show new intensity-intensity correlations involving both path and polarization phases, formally similar to those for four-particle GHZ states. For fixed polarization phases, the correlations reduce to the Hanbury Brown-Twiss phase correlations. It is also shown that these classical correlations violate noncontextuality.

  15. Cosmic absorption of ultra high energy particles

    E-Print Network [OSTI]

    Ruffini, R; Xue, S -S

    2015-01-01T23:59:59.000Z

    This paper summarizes the limits on propagation of ultra high energy particles in the Universe, set up by their interactions with cosmic background of photons and neutrinos. By taking into account cosmic evolution of these backgrounds and considering appropriate interactions we derive the mean free path for ultra high energy photons, protons and neutrinos. For photons the relevant processes are the Breit-Wheeler process as well as the double pair production process. For protons the relevant reactions are the photopion production and the Bethe-Heitler process. We discuss the interplay between the energy loss length and mean free path for the Bethe-Heitler process. Neutrino opacity is determined by its scattering off the cosmic background neutrino. We compute for the first time the high energy neutrino horizon as a function of its energy.

  16. The Spine of the Cosmic Web

    E-Print Network [OSTI]

    Miguel A. Aragon-Calvo; Erwin Platen; Rien van de Weygaert; Alexander S. Szalay

    2010-09-05T23:59:59.000Z

    We present the SpineWeb framework for the topological analysis of the Cosmic Web and the identification of its walls, filaments and cluster nodes. Based on the watershed segmentation of the cosmic density field, the SpineWeb method invokes the local adjacency properties of the boundaries between the watershed basins to trace the critical points in the density field and the separatrices defined by them. The separatrices are classified into walls and the spine, the network of filaments and nodes in the matter distribution. Testing the method with a heuristic Voronoi model yields outstanding results. Following the discussion of the test results, we apply the SpineWeb method to a set of cosmological N-body simulations. The latter illustrates the potential for studying the structure and dynamics of the Cosmic Web.

  17. Cosmic-ray diffusion in magnetized turbulence

    E-Print Network [OSTI]

    Tautz, R C

    2015-01-01T23:59:59.000Z

    The problem of cosmic-ray scattering in the turbulent electromagnetic fields of the interstellar medium and the solar wind is of great importance due to the variety of applications of the resulting diffusion coefficients. Examples are diffusive shock acceleration, cosmic-ray observations, and, in the solar system, the propagation of coronal mass ejections. In recent years, it was found that the simple diffusive motion that had been assumed for decades is often in disagreement both with numerical and observational results. Here, an overview is given of the interaction processes of cosmic rays and turbulent electromagnetic fields. First, the formation of turbulent fields due to plasma instabilities is treated, where especially the non-linear behavior of the resulting unstable wave modes is discussed. Second, the analytical and the numerical side of high-energy particle propagation will be reviewed by presenting non-linear analytical theories and Monte-Carlo simulations. For the example of the solar wind, the im...

  18. Cosmic Rays from Supernovae Proven to Hit Earth

    Broader source: Energy.gov [DOE]

    A new study confirms that cosmic rays are born in the violent aftermath of supernovas, exploding stars throughout the galaxy.

  19. Ultra High Energy Cosmic Ray Accelerators

    E-Print Network [OSTI]

    Angela V. Olinto

    1999-11-09T23:59:59.000Z

    The surprising lack of a high energy cutoff in the cosmic ray spectrum at the highest energies together with an apparently isotropic distribution of arrival directions have strongly challenged most models proposed for the acceleration of ultra high energy cosmic rays. Young neutron star winds may be able to explain the mystery. We discuss this recent proposal after summarizing the observational challenge and plausible acceleration sites. Young neutrons star winds differ from alternative models in the predictions for composition, spectrum, and angular distribution which will be tested in future experiments.

  20. Cosmic strings: A problem or a solution

    SciTech Connect (OSTI)

    Bennett, D.P.; Bouchet, F.R.

    1987-10-01T23:59:59.000Z

    The most fundamental issue in the theory of cosmic strings is addressed by means of Numerical Simulations: the existence of a scaling solution. The resolution of this question will determine whether cosmic strings can form the basis of an attractive theory of galaxy formation or prove to be a cosmological disaster like magnetic monopoles or domain walls. After a brief discussion of our numerical technique, results are presented which, though still preliminary, offer the best support to date of this scaling hypothesis. 6 refs., 2 figs.

  1. Simulations of Cosmic Chemical Enrichment with Hypernova

    E-Print Network [OSTI]

    Chiaki Kobayashi

    2006-11-27T23:59:59.000Z

    We simulate cosmic chemical enrichment with a hydrodynamical model including supernova and hypernova feedback. We find that the majority of stars in present-day massive galaxies formed in much smaller galaxies at high redshifts, despite their late assembly times. The hypernova feedback drives galactic outflows efficiently in low mass galaxies, and these winds eject heavy elements into the intergalactic medium. The ejected baryon fraction is larger for less massive galaxies, correlates well with stellar metallicity. The observed mass-metallicity relation is well reproduced as a result of the mass-dependent galactic winds. We also predict the cosmic supernova and gamma-ray burst rate histories.

  2. Constraining Cosmic Magnetic Fields by a Measurement of

    E-Print Network [OSTI]

    Erdmann, Martin

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 7 Energy-Energy-Correlations 51 7.1 Definition of Energy-EnergyConstraining Cosmic Magnetic Fields by a Measurement of Energy-Energy-Correlations with the Pierre Ultra High Energy Cosmic Rays 3 2.1 Cosmic Rays with Energies below 4 Ee

  3. Iron and Steel Energy Intensities

    U.S. Energy Information Administration (EIA) Indexed Site

    If you are having trouble, call 202-586-8800 for help. Home > >Energy Users > Energy Efficiency Page > Iron and Steel Energy Intensities First Use of Energy Blue Bullet First Use...

  4. The Frontier times magazine, 1923-1954: an index and brief history

    E-Print Network [OSTI]

    Hambric, Jacqueline Barnett

    1979-01-01T23:59:59.000Z

    interview with J. Marvin Hunter, Jr. , October 3, 1978. 29. Ibid. 30. [Hunter] n[Subscription Increase]" Frontier Times 29 (4) (Jan. , 1951), p. 101. 31. Telephone interview with J. Marvin Hunter, Jr. October 3, 1978. 32. Ibid. 33. Ibid, 34. Rothe... Trail Driving Days, " 5 (1) 20-22 {Oct. 1927) Abbott, E. CME 14(11) 497-498 (Aug. 1937) [ Abbott, E. C. ], 2 (10) 20-23 (July 1925) "Abel Korgan, Soldier and RoseoE? 18 (4) 175-180 (Jan. 1941) "Abel Horgan's Experience at GoliadE? 18(8) 339...

  5. A review of "Russia’s Steppe Frontier. The Making of a Colonial Empire." by Michael Khodarkovsky 

    E-Print Network [OSTI]

    Jakub Basista

    2004-01-01T23:59:59.000Z

    efforts is a solid, working foundation. Michael Khodarkovsky. Russia?s Steppe Frontier. The Making of a Colonial Empire, 1500-1800. Bloomington: Indiana University Press, 2002. Indiana-Michigan Series in Russian and East European Studies. xiv + 290 pp... and the coasts of the Pacific Ocean. It is the growth of the Russia?s expansion to these territories, along with its mechanisms, that Michael Khodarkovsky analyzes in his work Russia?s Steppe Frontier. After reading the book and looking at its title, I am...

  6. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1994-08-16T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  7. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1995-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  8. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, L.H.

    1995-10-17T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  9. Gamma radiation field intensity meter

    DOE Patents [OSTI]

    Thacker, Louis H. (Knoxville, TN)

    1994-01-01T23:59:59.000Z

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  10. Solar Variability, Cosmic Rays and Climate: What's up? The topic of possible relations between solar and cosmic

    E-Print Network [OSTI]

    Usoskin, Ilya G.

    Preface Solar Variability, Cosmic Rays and Climate: What's up? The topic of possible relations between solar and cosmic ray variability on one hand, and Earth's climate on the other hand, is quite in Space Research topical issue on Solar Variability, Cosmic Rays and Climate presents a collection

  11. Magnetic monopole searches in the cosmic radiation

    E-Print Network [OSTI]

    Ivan De Mitri

    2002-07-22T23:59:59.000Z

    There has been a big effort in the past twenty years with at least a couple of generations of experiments which searched for supermassive GUT magnetic monopoles in the cosmic radiation. Here a short review of these searches is given, together with a brief description of the theoretical framework and of the detection techniques.

  12. The Polarization of the Cosmic Microwave Background

    E-Print Network [OSTI]

    Matias Zaldarriaga

    2003-05-15T23:59:59.000Z

    We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use of polarization as a test of the inflationary paradigm. We discuss some physical processes that affect the CMB polarization after recombination such as gravitational lensing and the reionization of the universe.

  13. Accelerator Data for Cosmic Ray Physics

    E-Print Network [OSTI]

    M. G. Albrow

    2010-09-21T23:59:59.000Z

    I present selected examples of accelerator data, mainly from hadron colliders, that are relevant for understanding cosmic ray showers. I focus on the forward region, $x_{Feynman} > 0.05$, where high energy data are scarce, since the emphasis in collider physics became high-$p_T$ phenomena.

  14. Production of Axions by Cosmic Magnetic Helicity

    E-Print Network [OSTI]

    L. Campanelli; M. Giannotti

    2006-04-05T23:59:59.000Z

    We investigate the effects of an external magnetic helicity production on the evolution of the cosmic axion field. It is shown that a helicity larger than (few \\times 10^{-15} G)^2 Mpc, if produced at temperatures above a few GeV, is in contradiction with the existence of the axion, since it would produce too much of an axion relic abundance.

  15. Numerical likelihood analysis of cosmic ray anisotropies

    SciTech Connect (OSTI)

    Carlos Hojvat et al.

    2003-07-02T23:59:59.000Z

    A numerical likelihood approach to the determination of cosmic ray anisotropies is presented which offers many advantages over other approaches. It allows a wide range of statistically meaningful hypotheses to be compared even when full sky coverage is unavailable, can be readily extended in order to include measurement errors, and makes maximum unbiased use of all available information.

  16. Nuclear War from a Cosmic Perspective

    E-Print Network [OSTI]

    Tegmark, Max

    2015-01-01T23:59:59.000Z

    I discuss the impact of computer progress on nuclear war policy, both by enabling more accurate nuclear winter simulations and by affecting the probability of war starting accidentally. I argue that from a cosmic perspective, humanity's track record of risk mitigation is inexcusably pathetic, jeopardizing the potential for life to flourish for billions of years.

  17. Kink in superconducting cosmic string: exact solution

    E-Print Network [OSTI]

    Ernst Trojan

    2014-12-24T23:59:59.000Z

    We solve the equations of motion and find the Lorentz transformation associated with a kink in superconducting cosmic string. The kink velocity does not depend on its amplitude. The kink amplitude cannot be arbitrary but it varies within definite range and determines the explicit form of the relevant Lorentz transformation.

  18. Observing Air Showers from Cosmic Superluminal Particles

    E-Print Network [OSTI]

    Luis Gonzalez-Mestres

    1997-12-26T23:59:59.000Z

    The Poincar\\'e relativity principle has been tested at low energy with great accuracy, but its extrapolation to very high-energy phenomena is much less well established. Lorentz symmetry can be broken at Planck scale due to the renormalization of gravity or to some deeper structure of matter: we expect such a breaking to be a very high energy and very short distance phenomenon. If textbook special relativity is only an approximate property of the equations describing a sector of matter above some critical distance scale, an absolute local frame (the "vacuum rest frame", VRF) can possibly be found and superluminal sectors of matter may exist related to new degrees of freedom not yet discovered experimentally. The new superluminal particles ("superbradyons", i.e. bradyons with superluminal critical speed) would have positive mass and energy, and behave kinematically like "ordinary" particles (those with critical speed in vacuum equal to c, the speed of light) apart from the difference in critical speed (c_i >> c where c_i is the critical speed of a superluminal sector). They may be the ultimate building blocks of matter At speed v > c, they are expected to release "Cherenkov" radiation ("ordinary" particles) in vacuum. Superluminal particles could provide most of the cosmic (dark) matter and produce very high-energy cosmic rays. We discuss: a) the possible relevance of superluminal matter to the composition, sources and spectra of high-energy cosmic rays; b) signatures and experiments allowing to possibly explore such effects. Very large volume and unprecedented background rejection ability are crucial requirements for any detector devoted to the search for cosmic superbradyons. Future cosmic-ray experiments using air-shower detectors (especially from space) naturally fulfil both requirements.

  19. Study of Dispersion of Mass Distribution of Ultra-High Energy Cosmic Rays using a Surface Array of Muon and Electromagnetic Detectors

    E-Print Network [OSTI]

    Vícha, Jakub; Nosek, Dalibor; Ebr, Jan

    2015-01-01T23:59:59.000Z

    We consider a hypothetical observatory of ultra-high energy cosmic rays consisting of two surface detector arrays that measure independently electromagnetic and muon signals induced by air showers. Using the constant intensity cut method, sets of events ordered according to each of both signal sizes are compared giving the number of matched events. Based on its dependence on the zenith angle, a parameter sensitive to the dispersion of the distribution of the logarithmic mass of cosmic rays is introduced. The results obtained using two post-LHC models of hadronic interactions are very similar and indicate a weak dependence on details of these interactions.

  20. Proceedings of the 6th International Conference on Frontiers of Design and Manufacturing ADVANCES IN LASER FORMING RESEARCH

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    of laser forming are presented based on the work in Manufacturing Research Laboratory (MRL) of ColumbiaProceedings of the 6th International Conference on Frontiers of Design and Manufacturing -1- ADVANCES IN LASER FORMING RESEARCH Y. Lawrence Yao, Peng Cheng, Duncan Pratt and Yajun Fan Department

  1. Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy Science: A Talk from Leo Holberg and Allen Mills

    ScienceCinema (OSTI)

    Holberg, Leo; Mills, Allen [NIST

    2011-04-28T23:59:59.000Z

    Leo Holberg and Allen Mills present a talk at Frontiers in Laser Cooling, Single-Molecule Biophysics and Energy Science, a scientific symposium honoring Steve Chu, director of Lawrence Berkeley National Laboratory and recipient of the 1997 Nobel Prize in Physics. The symposium was held August 30, 2008 in Berkeley.

  2. 'Matebili' Thompson Africa in the 19th century was a land of mystery and adventure, a frontier far wilder than

    E-Print Network [OSTI]

    Francis, Paul

    'Matebili' Thompson Africa in the 19th century was a land of mystery and adventure, a frontier far wilder than the "wild west". Francis 'Matebili' Thompson, Gogo's grandfather, had his share in some in 1850 #12;... My father was the third son of Francis Thompson, of Cornforth Hill, Richmond, Yorkshire

  3. Pecularities of cosmic ray modulation in the solar minimum 23/24

    E-Print Network [OSTI]

    Alania, M V; Wawrzynczak, A

    2015-01-01T23:59:59.000Z

    We study changes of the galactic cosmic ray (GCR) intensity for the ending period of the solar cycle 23 and the beginning of the solar cycle 24 using neutron monitors experimental data. We show that an increase of the GCR intensity in 2009 is generally related with decrease of the solar wind velocity U, the strength B of the interplanetary magnetic field (IMF), and the drift in negative (Aneg) polarity epoch. We present that temporal changes of rigidity dependence of the GCR intensity variation before reaching maximum level in 2009 and after it, do not noticeably differ from each other. The rigidity spectrum of the GCR intensity variations calculated based on neutron monitors data (for rigidities greaten than 10 GV) is hard in the minimum and near minimum epoch. We do not recognize any non-ordinary changes in the physical mechanism of modulation of the GCR intensity in the rigidity range of GCR particles to which neutron monitors respond. We compose 2-D non stationary model of transport equation to describe v...

  4. Extracting cosmic microwave background polarisation from satellite astrophysical maps

    E-Print Network [OSTI]

    C. Baccigalupi; F. Perrotta; G. De Zotti; G. F. Smoot; C. Burigana; D. Maino; L. Bedini; E. Salerno

    2004-07-12T23:59:59.000Z

    We present the application of the Fast Independent Component Analysis ({\\ica}) technique for blind component separation to polarized astrophysical emission. We study how the Cosmic Microwave Background (CMB) polarized signal, consisting of $E$ and $B$ modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foreground emission and instrumental noise. {We implement Monte Carlo chains varying the CMB and noise realizations in order to asses the average capabilities of the algorithm and their variance.} We perform the analysis of all sky maps simulated according to the {\\sc Planck} satellite capabilities, modelling the sky signal as a superposition of the CMB and of the existing simulated polarization templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB $E$-mode can be recovered on all scales up to $\\ell\\simeq 1000$, corresponding to the fourth acoustic oscillation, while the $B$-mode power spectrum can be detected, up to its turnover at $\\ell\\simeq 100$, if the ratio of tensor to scalar contributions to the temperature quadrupole exceeds 30%. The power spectrum of the cross correlation between total intensity and polarization, $TE$, can be recovered up to $\\ell\\simeq 1200$, corresponding to the seventh $TE$ acoustic oscillation.

  5. Extracting cosmic microwave background polarization from satelliteastrophysical maps

    SciTech Connect (OSTI)

    Baccigalpi, C.; Perrotta, F.; Zotti, G.D.; Smoot, G.F.; Burigana,C.; Maino, D.; Bedini, L.; Salerno, E.

    2004-05-02T23:59:59.000Z

    We present the application of the fast independent component analysis (FASTICA) technique for blind component separation to polarized astrophysical emission. We study how the cosmic microwave background (CMB) polarized signal, consisting of E and B modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foreground emission and instrumental noise. We implement Monte Carlo chains varying the CMB and noise realizations in order to assess the average capabilities of the algorithm and their variance. We perform the analysis of all-sky maps simulated according to the Planck satellite capabilities, modeling the sky signal as a superposition of the CMB and of the existing simulated polarization templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB E mode can be recovered on all scales up to lsimilar or equal to 1000, corresponding to the fourth acoustic oscillation, while the B-mode power spectrum can be detected, up to its turnover at lsimilar or equal to 100, if the ratio of tensor to scalar contributions to the temperature quadrupole exceeds 30 per cent. The power spectrum of the cross-correlation between total intensity and polarization, TE, can be recovered up to lsimilar or equal to 1200, corresponding to the seventh TE acoustic oscillation.

  6. GALACTIC COSMIC-RAY ENERGY SPECTRA AND COMPOSITION DURING THE 2009-2010 SOLAR MINIMUM PERIOD

    SciTech Connect (OSTI)

    Lave, K. A.; Binns, W. R.; Israel, M. H. [Department of Physics and the McDonnell Center for the Space Sciences, Washington University, St. Louis, MO 63130 (United States); Wiedenbeck, M. E. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Christian, E. R.; De Nolfo, G. A.; Von Rosenvinge, T. T. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Cummings, A. C.; Davis, A. J.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C. [California Institute of Technology, Pasadena, CA 91125 (United States)

    2013-06-20T23:59:59.000Z

    We report new measurements of the elemental energy spectra and composition of galactic cosmic rays during the 2009-2010 solar minimum period using observations from the Cosmic Ray Isotope Spectrometer (CRIS) onboard the Advanced Composition Explorer. This period of time exhibited record-setting cosmic-ray intensities and very low levels of solar activity. Results are given for particles with nuclear charge 5 {<=} Z {<=} 28 in the energy range {approx}50-550 MeV nucleon{sup -1}. Several recent improvements have been made to the earlier CRIS data analysis, and therefore updates of our previous observations for the 1997-1998 solar minimum and 2001-2003 solar maximum are also given here. For most species, the reported intensities changed by less than {approx}7%, and the relative abundances changed by less than {approx}4%. Compared with the 1997-1998 solar minimum relative abundances, the 2009-2010 abundances differ by less than 2{sigma}, with a trend of fewer secondary species observed in the more recent time period. The new 2009-2010 data are also compared with results of a simple ''leaky-box'' galactic transport model combined with a spherically symmetric solar modulation model. We demonstrate that this model is able to give reasonable fits to the energy spectra and the secondary-to-primary ratios B/C and (Sc+Ti+V)/Fe. These results are also shown to be comparable to a GALPROP numerical model that includes the effects of diffusive reacceleration in the interstellar medium.

  7. The Sticky Geometry of the Cosmic Web

    E-Print Network [OSTI]

    Johan Hidding; Rien van de Weygaert; Gert Vegter; Bernard J. T. Jones; Monique Teillaud

    2012-05-08T23:59:59.000Z

    In this video we highlight the application of Computational Geometry to our understanding of the formation and dynamics of the Cosmic Web. The emergence of this intricate and pervasive weblike structure of the Universe on Megaparsec scales can be approximated by a well-known equation from fluid mechanics, the Burgers' equation. The solution to this equation can be obtained from a geometrical formalism. We have extended and improved this method by invoking weighted Delaunay and Voronoi tessellations. The duality between these tessellations finds a remarkable and profound reflection in the description of physical systems in Eulerian and Lagrangian terms. The resulting Adhesion formalism provides deep insight into the dynamics and topology of the Cosmic Web. It uncovers a direct connection between the conditions in the very early Universe and the complex spatial patterns that emerged out of these under the influence of gravity.

  8. Wiggly cosmic strings accrete dark energy

    E-Print Network [OSTI]

    Pedro F. Gonzalez-Diaz; Jose A. Jimenez Madrid

    2005-06-29T23:59:59.000Z

    This paper deals with a study of the cylindrically symmetric accretion of dark energy with equation of state $p=w\\rho$ onto wiggly straight cosmic strings. We have obtained that when $w>-1$ the linear energy density in the string core gradually increases tending to a finite maximum value as time increases for all considered dark energy models. On the regime where the dominant energy condition is violated all such models predict a steady decreasing of the linear energy density of the cosmic strings as phantom energy is being accreted. The final state of the string after such an accretion process is a wiggleless defect. It is argued however that if accreation of phantom energy would proceed by successive quantum steps then the defect would continue losing linear energy density until a minimum nonzero value which can be quite smaller than that corresponding to the unperturbed string.

  9. Generalized Strong Curvature Singularities and Cosmic Censorship

    E-Print Network [OSTI]

    W. Rudnicki; R. J. Budzynski; W. Kondracki

    2002-03-19T23:59:59.000Z

    A new definition of a strong curvature singularity is proposed. This definition is motivated by the definitions given by Tipler and Krolak, but is significantly different and more general. All causal geodesics terminating at these new singularities, which we call generalized strong curvature singularities, are classified into three possible types; the classification is based on certain relations between the curvature strength of the singularities and the causal structure in their neighborhood. A cosmic censorship theorem is formulated and proved which shows that only one class of generalized strong curvature singularities, corresponding to a single type of geodesics according to our classification, can be naked. Implications of this result for the cosmic censorship hypothesis are indicated.

  10. 2Cosmic Bar Graphs Galaxy Type

    E-Print Network [OSTI]

    in the cluster are spirals? Problem 2 ­ Gamma-ray bursts happen about once each day. The bar graph to the right there are 160 total galaxies, the fraction of spirals is 137/160 = 0.86, or equivalently 86%. Problem 2 ­ Gamma-ray2Cosmic Bar Graphs 0 20 40 60 80 100 S E SB I Galaxy Type Number 0 200 400 600 800 1000 FB SB Burst

  11. Gravity waves from cosmic bubble collisions

    SciTech Connect (OSTI)

    Salem, Michael P.; Saraswat, Prashant; Shaghoulian, Edgar, E-mail: mpsalem@stanford.edu, E-mail: ps88@stanford.edu, E-mail: edgars@stanford.edu [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, California 94305 (United States)

    2013-02-01T23:59:59.000Z

    Our local Hubble volume might be contained within a bubble that nucleated in a false vacuum with only two large spatial dimensions. We study bubble collisions in this scenario and find that they generate gravity waves, which are made possible in this context by the reduced symmetry of the global geometry. These gravity waves would produce B-mode polarization in the cosmic microwave background, which could in principle dominate over the inflationary background.

  12. Solar panels as cosmic-ray detectors

    E-Print Network [OSTI]

    Stella, Carlo; Assis, Pedro; Brogueira, Pedro; Santo, Catarina Espirito; Goncalves, Patricia; Pimenta, Mario; De Angelis, Alessandro

    2014-01-01T23:59:59.000Z

    Due to fundamental limitations of accelerators, only cosmic rays can give access to centre-of- mass energies more than one order of magnitude above those reached at the LHC. In fact, extreme energy cosmic rays (1018 eV - 1020 eV) are the only possibility to explore the 100 TeV energy scale in the years to come. This leap by one order of magnitude gives a unique way to open new horizons: new families of particles, new physics scales, in-depth investigations of the Lorentz symmetries. However, the flux of cosmic rays decreases rapidly, being less than one particle per square kilometer per year above 1019 eV: one needs to sample large surfaces. A way to develop large-effective area, low cost, detectors, is to build a solar panel-based device which can be used in parallel for power generation and Cherenkov light detection. Using solar panels for Cherenkov light detection would combine power generation and a non-standard detection device.

  13. Observing the Multiverse with Cosmic Wakes

    E-Print Network [OSTI]

    Matthew Kleban; Thomas S. Levi; Kris Sigurdson

    2011-09-15T23:59:59.000Z

    Current theories of the origin of the Universe, including string theory, predict the existence of a multiverse containing many bubble universes. These bubble universes will generically collide, and collisions with ours produce cosmic wakes that enter our Hubble volume, appear as unusually symmetric disks in the cosmic microwave background (CMB) and disturb large scale structure (LSS). There is preliminary observational evidence consistent with one or more of these disturbances on our sky. However, other sources can produce similar features in the CMB temperature map and so additional signals are needed to verify their extra-universal origin. Here we find, for the first time, the detailed three-dimensional shape and CMB temperature and polarization signals of the cosmic wake of a bubble collision in the early universe consistent with current observations. The predicted polarization pattern has distinctive features that when correlated with the corresponding temperature pattern are a unique and striking signal of a bubble collision. These features represent the first verifiable prediction of the multiverse paradigm and might be detected by current experiments such as Planck and future CMB polarization missions. A detection of a bubble collision would confirm the existence of the Multiverse, provide compelling evidence for the string theory landscape, and sharpen our picture of the Universe and its origins.

  14. The impact of trade costs on rare earth exports : a stochastic frontier estimation approach.

    SciTech Connect (OSTI)

    Sanyal, Prabuddha; Brady, Patrick Vane; Vugrin, Eric D.

    2013-09-01T23:59:59.000Z

    The study develops a novel stochastic frontier modeling approach to the gravity equation for rare earth element (REE) trade between China and its trading partners between 2001 and 2009. The novelty lies in differentiating betweenbehind the border' trade costs by China and theimplicit beyond the border costs' of China's trading partners. Results indicate that the significance level of the independent variables change dramatically over the time period. While geographical distance matters for trade flows in both periods, the effect of income on trade flows is significantly attenuated, possibly capturing the negative effects of financial crises in the developed world. Second, the total export losses due tobehind the border' trade costs almost tripled over the time period. Finally, looking atimplicit beyond the border' trade costs, results show China gaining in some markets, although it is likely that some countries are substituting away from Chinese REE exports.

  15. Neutrino physics with an intense \

    E-Print Network [OSTI]

    R. Henning

    2010-11-16T23:59:59.000Z

    We study some of the physics potential of an intense $1\\,\\mathrm{MCi}$ $^{51}\\mathrm{Cr}$ source combined with the {\\sc Majorana Demonstrator} enriched germanium detector array. The {\\sc Demonstrator} will consist of detectors with ultra-low radioactive backgrounds and extremely low energy thresholds of~$\\sim 400\\,\\mathrm{eV}$. We show that it can improve the current limit on the neutrino magnetic dipole moment. We briefly discuss physics applications of the charged-current reaction of the $^{51}\\mathrm{Cr} neutrino with the $^{73}\\mathrm{Ge} isotope. Finally, we argue that the rate from a realistic, intense tritium source is below the detectable limit of even a tonne-scale HPGe experiment

  16. anomalous cosmic rays: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (arXiv) Summary: We consider the propagation of galactic cosmic rays in the fractal interstellar medium. Steady state solution of the fractional diffusion equation,...

  17. anomalous cosmic ray: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (arXiv) Summary: We consider the propagation of galactic cosmic rays in the fractal interstellar medium. Steady state solution of the fractional diffusion equation,...

  18. NERSC Helps Discover Cosmic Transients - NERSC Science News June...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lab) to expose relatively rare and fleeting cosmic events, like supernovae and gamma ray bursts. In fact, during the commissioning phase alone, the survey has already uncovered...

  19. The Hubble Web: The Dark Matter Problem and Cosmic Strings

    E-Print Network [OSTI]

    Stephon Alexander

    2007-02-27T23:59:59.000Z

    I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing baryonic and warm dark matter into disks. These cosmic strings survive as configurations which thread spiral and elliptical galaxies leading to the observed flatness of rotation curves and the Tully-Fisher relation. We find a relationship between the rotational velocity of the galaxy and the string tension and discuss the testability of this model.

  20. A Flat Universe from High-Resolution Maps of the Cosmic Microwave Background Radiation

    E-Print Network [OSTI]

    2000-01-01T23:59:59.000Z

    in the Cosmic Background Radiation with the Cambridge CosmicCosmic Microwave Background Radiation arXiv:astro-ph/0004404Roma, Italy,. The blackbody radiation left over from the Big

  1. Solar Cells from Plastics? Mission Possible at the PHaSE Energy Research Center, UMass Amherst (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    SciTech Connect (OSTI)

    Russell, Thomas P; Lahti, Paul M. (PHaSE - Polymer-Based Materials for Harvesting Solar Energy) [PHaSE - Polymer-Based Materials for Harvesting Solar Energy; PHaSE Staff

    2011-05-01T23:59:59.000Z

    'Solar Cells from Plastics? Mission Possible at the PHaSE Energy Research Center, UMass Amherst' was submitted by the Polymer-Based Materials for Harvesting Solar Energy (PHaSE) EFRC to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. PHaSE, an EFRC co-directed by Thomas P. Russell and Paul M. Lahti at the University of Massachusetts, Amherst, is a partnership of scientists from six institutions: UMass (lead), Oak Ridge National Laboratory, Pennyslvania State University, Rensselaer Polytechnic Institute, and the University of Pittsburgh. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  2. The Center for Material Science of Nuclear Fuel (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Allen, Todd (Director, Center for Material Science of Nuclear Fuel); CMSNF Staff

    2011-11-02T23:59:59.000Z

    'The Center for Material Science of Nuclear Fuel (CMSNF)' was submitted by the CMSNF to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CMSNF, an EFRC directed by Todd Allen at the Idaho National Laboratory is a partnership of scientists from six institutions: INL (lead), Colorado School of Mines, University of Florida, Florida State University, Oak Ridge National Laboratory, and the University of Wisconsin at Madison. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Materials Science of Nuclear Fuels is 'to achieve a first-principles based understanding of the effect of irradiation-induced defects and microstructures on thermal transport in oxide nuclear fuels.' Research topics are: phonons, thermal conductivity, nuclear, extreme environment, radiation effects, defects, and matter by design.

  3. Autonomic Materials for Smarter, Safer, Longer-Lasting Batteries (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Thackeray, Michael (Director, Center for Electrical Energy Storage); CEES Staff

    2011-11-02T23:59:59.000Z

    'Autonomic Materials for Smarter, Safer, Longer-Lasting Batteries' was submitted by the Center for Electrical Energy Storage (CEES) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CEES, an EFRC directed by Michael Thackery at Argonne National Laboratory is a partnership of scientists from three institutions: ANL (lead), Northwestern University, and the University of Illinois at Urbana-Champaign. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Electrical Energy Storage is 'to acquire a fundamental understanding of interfacial phenomena controlling electrochemical processes that will enable dramatic improvements in the properties and performance of energy storage devices, notable Li ion batteries.' Research topics are: electrical energy storage, batteries, battery electrodes, electrolytes, adaptive materials, interfacial characterization, matter by design; novel materials synthesis, charge transport, and defect tolerant materials.

  4. Center for Materials at Irradiation and Mechanical Extremes at LANL (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Michael Nastasi (Director, Center for Materials at Irradiation and Mechanical Extremes); CMIME Staff

    2011-11-03T23:59:59.000Z

    'Center for Materials at Irradiation and Mechanical Extremes (CMIME) at LANL' was submitted by CMIME to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CMIME, an EFRC directed by Michael Nastasi at Los Alamos National Laboratory is a partnership of scientists from four institutions: LANL (lead), Carnegia Mellon University, the University of Illinois at Urbana Champaign, and the Massachusetts Institute of Technology. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  5. Undergraduate Research at the Center for Energy Efficient Materials (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum

    ScienceCinema (OSTI)

    Bowers, John (Director, Center for Energy Efficient Materials ); CEEM Staff

    2011-11-02T23:59:59.000Z

    'Undergraduate Research at the Center for Energy Efficient Materials (CEEM)' was submitted by CEEM to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CEEM, an EFRC directed by John Bowers at the University of California, Santa Barbara is a partnership of scientists from four institutions: UC, Santa Barbara (lead), UC, Santa Cruz, Los Alamos National Laboratory, and National Renewable Energy Laboratory. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Energy Efficient Materials is 'to discover and develop materials that control the interactions between light, electricity, and heat at the nanoscale for improved solar energy conversion, solid-state lighting, and conversion of heat into electricity.' Research topics are: solar photovoltaic, photonic, solid state lighting, optics, thermoelectric, bio-inspired, electrical energy storage, batteries, battery electrodes, novel materials synthesis, and scalable processing.

  6. Solar Cells from Plastics? Mission Possible at the PHaSE Energy Research Center, UMass Amherst (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Russell, Thomas P; Lahti, Paul M. (PHaSE - Polymer-Based Materials for Harvesting Solar Energy); PHaSE Staff

    2011-11-03T23:59:59.000Z

    'Solar Cells from Plastics? Mission Possible at the PHaSE Energy Research Center, UMass Amherst' was submitted by the Polymer-Based Materials for Harvesting Solar Energy (PHaSE) EFRC to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. PHaSE, an EFRC co-directed by Thomas P. Russell and Paul M. Lahti at the University of Massachusetts, Amherst, is a partnership of scientists from six institutions: UMass (lead), Oak Ridge National Laboratory, Pennyslvania State University, Rensselaer Polytechnic Institute, and the University of Pittsburgh. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  7. Moving from Petroleum to Plants to Energize our World (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    McCann, Maureen (Director, Center for Direct Catalytic Conversion of Biomass to Biofuels); C3Bio Staff

    2011-11-03T23:59:59.000Z

    'Moving from Petroleum to Plants to Energize our World' was submitted by the Center for Direct Catalytic Conversion of Biomass to Biofuels (C3Bio) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. C3Bio, an EFRC directed by Maureen McCann at Purdue University is a partnership between five institutions: Purdue (lead), Argonne National Laboratory, National Renewable Energy Laboratory, Northeastern University, and the University of Tennessee. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges.

  8. SNOWMASS WHITE PAPER - SLHC Endcap 1.4Optical Calorimetry Upgrades in CMS with Applications to NLC/T-LEP, Intensity Frontier, and Beyond

    E-Print Network [OSTI]

    Bilki, Burak; Winn, David R; Yetkin, Taylan

    2013-01-01T23:59:59.000Z

    Radiation damage in the plastic scintillator and/or readout WLS fibers in the HE endcap calorimeter 1.4radiation-hard pTerphenyl(pTP) or the fast phosphor ZnO:Ga. These tiles would be read-out by easily replaceable arrays of straight, parallel WLS fibers coupled to clear plastic-cladded quartz fibers of proven radiation resistance. We describe a second alternative with a new absorber matrix extending to 1.4

  9. High Intensity Polarized Electron Gun

    SciTech Connect (OSTI)

    Redwine, Robert

    2012-07-31T23:59:59.000Z

    The goal of the project was to investigate the possibility of building a very high intensity polarized electron gun for the Electron-Ion Collider. This development is crucial for the eRHIC project. The gun implements a large area cathode, ring-shaped laser beam and active cathode cooling. A polarized electron gun chamber with a large area cathode and active cathode cooling has been built and tested. A preparation chamber for cathode activation has been built and initial tests have been performed. Major parts for a load-lock chamber, where cathodes are loaded into the vacuum system, have been manufactured.

  10. Intensive Observation Period Projects Scheduled

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other NewsSpin andInterimInvokingInspector XE 20131 Intensive

  11. The New Energy Management Frontier: The Critical Role of a Systematic Management Approach in Making Technology Improvements Successful

    E-Print Network [OSTI]

    Feldman, J.

    The New Energy Management Frontier: The Critical Role of a Systematic Management Approach in Making Technology Improvements Successful Jon Feldman Senior Consultant Hatch Consulting Mississauga, Ontario, Canada ABSTRACT Improvements... in technology certainly playa pivotal role in the quest for increased energy efficiency. However, sophisticated industrial energy users are increasingly learning that technology alone cannot drive long-tenn, sustainable reductions in energy cost. The role...

  12. Cosmic acceleration and Brans-Dicke theory

    SciTech Connect (OSTI)

    Sharif, M., E-mail: msharif.math@pu.edu.pk; Waheed, S. [University of the Punjab, Department of Mathematics (Pakistan)

    2012-10-15T23:59:59.000Z

    We study the accelerated expansion of the universe by exploring the Brans-Dicke parameter in different eras. For this, we take the FRW universe model with a viscous fluid (without potential) and the Bianchi type-I universe model with a barotropic fluid (with and without a potential). We evaluate the deceleration parameter and the Brans-Dicke parameter to explore cosmic acceleration. It is concluded that accelerated expansion of the universe can also be achieved for higher values of the Brans-Dicke parameter in some cases.

  13. New parametrization of cosmic neutrino oscillations

    E-Print Network [OSTI]

    Palladino, Andrea

    2015-01-01T23:59:59.000Z

    A new parameterization of neutrinos oscillations in vacuum, assuming the conventional three flavor scheme, is proposed and discussed. Applications of this parameterization are considered, that concern the study of the flavor ratios, of their uncertainties, the expectations for the signal due to Glashow resonance. It is shown that a Gaussian treatment describes to a good level of approximation the effects of the uncertainties on the mixing angles and on the CP violating phase. The recently obtained agreement of observations with the hypothesis of cosmic neutrino oscillations is confirmed.

  14. Particle Production and Dissipative Cosmic Field

    E-Print Network [OSTI]

    H. Fujisaki; K. Kumekawa; M. Yamaguchi; M. Yoshimura

    1995-08-27T23:59:59.000Z

    Large amplitude oscillation of cosmic field that may occur right after inflation and in the decay process of weakly interacting fields gives rise to violent particle production via the parametric resonance. In the large amplitude limit the problem of back reaction against the field oscillation is solved and the energy spectrum of created particles is determined in a semi-classical approximation. For large enough coupling or large enough amplitude the resulting energy spectrum is broadly distributed, implying larger production of high energy particles than what a simple estimate of the reheating temperature due to the Born formula would suggest.

  15. Revealing Cosmic Magnetism with Radio Polarimetry

    E-Print Network [OSTI]

    Bryan M. Gaensler

    2007-12-18T23:59:59.000Z

    While gravitation sustains the on-going evolution of the cosmos, it is magnetism that breaks gravity's symmetry and that provides the pathway to the non-thermal Universe. By enabling processes such as anisotropic pressure support, particle acceleration, and jet collimation, magnetism has for billions of years regulated the feedback vital for returning matter to the interstellar and intergalactic medium. After reviewing recent results that demonstrate the unique view of magnetic fields provided by radio astronomy, I explain how the Square Kilometre Array will provide data that will reveal what cosmic magnets look like, how they formed, and what role they have played in the evolving Universe.

  16. Adhesion and the Geometry of the Cosmic Web

    E-Print Network [OSTI]

    Johan Hidding; Rien van de Weygaert; Gert Vegter; Bernard J. T. Jones

    2012-11-22T23:59:59.000Z

    We present a new way to formulate the geometry of the Cosmic Web in terms of Lagrangian space. The Adhesion model has an ingenious geometric interpretation out of which the spine of the Cosmic Web emerges naturally. Within this context we demonstrate a deep connection of the relation between Eulerian and Lagrangian space with that between Voronoi and Delaunay tessellations.

  17. Plasmoid impacts on neutron stars and highest energy cosmic rays

    E-Print Network [OSTI]

    C. Litwin; R. Rosner

    2001-04-04T23:59:59.000Z

    Particle acceleration by electrostatic polarization fields that arise in plasmas streaming across magnetic fields is discussed as a possible acceleration mechanism of highest-energy cosmic rays. Specifically, plasmoids arising in planetoid impacts onto neutron star magnetospheres are considered. We find that such impacts at plausible rates may account for the observed flux and energy spectrum of the highest energy cosmic rays.

  18. Non Thermal Features in the Cosmic Neutrino Background

    E-Print Network [OSTI]

    G. Mangano

    2006-03-22T23:59:59.000Z

    I review some of the basic information on the Cosmic Neutrino Background momentum distribution. In particular, I discuss how present data from several cosmological observables such as Big Bang Nucleosynthesis, Cosmic Microwave Background and Large Scale Structure power spectrum constrain possible deviations from a standard Fermi-Dirac thermal distribution.

  19. An electronic radiation of blackbody: Cosmic electron background

    E-Print Network [OSTI]

    Jian-Miin Liu

    2008-02-23T23:59:59.000Z

    The Universe owns the electronic radiation of blackbody at temperature 2.725 K, which we call the cosmic electron background. We calculate its radiation spectrum. The energy distribution of number density of electrons in the cosmic electron background becomes zero as energy goes to both zero and infinity. It has one maximum peak near the energy level of 10**(-23) J.

  20. 30TH INTERNATIONAL COSMIC RAY CONFERENCE The TALE Tower Detector

    E-Print Network [OSTI]

    30TH INTERNATIONAL COSMIC RAY CONFERENCE The TALE Tower Detector D. R. BERGMAN1 , FOR THE TA and extend the range of its energy coverage to lower energies. One of the TALE detectors is a "tower cosmic rays with energies between 1016.5 and 1018 eV. To achieve this low-energy sensitivity the tower

  1. The effects of coronal mass ejection on galactic cosmic rays in the high latitude heliosphere: Observations from Ulysses` first orbit

    SciTech Connect (OSTI)

    Bothmer, V.; Heber, B.; Kunow, H.; Mueller-Mellin, R.; Wibberenz, G. [Univ. of Kiel (Germany). Institut fuer Kernphysik; Gosling, J.T. [Los Alamos National Lab., NM (United States); Balogh, A. [Imperial College, London (United Kingdom). Blackett Lab.; Raviart, A. [CEA, Gif-sur-Yvette (France). Service d`Astrophysique; Paizis, C. [Univ. di Milano (Italy). Istituto di Fisica Cosmica CNR

    1997-10-01T23:59:59.000Z

    During its first solar orbit the Ulysses spacecraft detected several coronal mass ejections (CMEs) at high heliographic latitudes. The authors present first observations on the effects of these high latitude CMEs on galactic cosmic rays (GCRs) using measurements from the Kiel Electron Telescope (KET) which is part of the Cosmic Ray and Solar Particle Investigation (COSPIN) experiment, the Los Alamos SWOOPS (Solar Wind Observations Over the Poles of the Sun) experiment and the magnetic field experiments. They find the passage of these CMEs over the spacecraft to be associated with short term decreases of GCR intensities The relatively weak shocks in these events, driven by the CMEs` over-expansion, had no strong influence on the GCRs. The intensity minimums of GCRs occurred on closed magnetic field lines inside the CMEs themselves as indicated by bidirectional fluxes of suprathermal electrons. Short episodes of intensity increases of GCRs inside CMEs at times when the bidirectional fluxes of suprathermal electrons disappeared, can be interpreted as evidence that GCRs can easily access the interior of those CMEs in which open magnetic field lines are embedded.

  2. Theoretical and Experimental Studies of Elementary Particle Physics

    SciTech Connect (OSTI)

    Evans, Harold G [Indiana University] [Indiana University; Kostelecky, V Alan [Indiana University] [Indiana University; Musser, James A [Indiana University] [Indiana University

    2013-07-29T23:59:59.000Z

    The elementary particle physics research program at Indiana University spans a broad range of the most interesting topics in this fundamental field, including important contributions to each of the frontiers identified in the recent report of HEPAP's Particle Physics Prioritization Panel: the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. Experimentally, we contribute to knowledge at the Energy Frontier through our work on the D0 and ATLAS collaborations. We work at the Intensity Frontier on the MINOS and NOvA experiments and participate in R&D for LBNE. We are also very active on the theoretical side of each of these areas with internationally recognized efforts in phenomenology both in and beyond the Standard Model and in lattice QCD. Finally, although not part of this grant, members of the Indiana University particle physics group have strong involvement in several astrophysics projects at the Cosmic Frontier. Our research efforts are divided into three task areas. The Task A group works on D0 and ATLAS; Task B is our theory group; and Task C contains our MINOS, NOvA, and LBNE (LArTPC) research. Each task includes contributions from faculty, senior scientists, postdocs, graduate and undergraduate students, engineers, technicians, and administrative personnel. This work was supported by DOE Grant DE-FG02-91ER40661. In the following, we describe progress made in the research of each task during the final period of the grant, from November 1, 2009 to April 30, 2013.

  3. Experimental transport of intensity diffraction tomography

    E-Print Network [OSTI]

    Lee, Justin Wu

    2011-01-01T23:59:59.000Z

    In this thesis, I perform intensity-based tomographic phase imaging in two ways. First, I utilize the paraxial transport of intensity equation (TIE) to construct phase maps of a phase object at multiple projection angles ...

  4. Cosmic Ray Rejection by Linear Filtering of Single Images

    E-Print Network [OSTI]

    James E. Rhoads

    2000-02-02T23:59:59.000Z

    We present a convolution-based algorithm for finding cosmic rays in single well-sampled astronomical images. The spatial filter used is the point spread function (approximated by a Gaussian) minus a scaled delta function, and cosmic rays are identified by thresholding the filtered image. This filter searches for features with significant power at spatial frequencies too high for legitimate objects. Noise properties of the filtered image are readily calculated, which allows us to compute the probability of rejecting a pixel not contaminated by a cosmic ray (the false alarm probability). We demonstrate that the false alarm probability for a pixel containing object flux will never exceed the corresponding probability for a blank sky pixel, provided we choose the convolution kernel appropriately. This allows confident rejection of cosmic rays superposed on real objects. Identification of multiple-pixel cosmic ray hits can be enhanced by running the algorithm iteratively, replacing flagged pixels with the background level at each iteration.

  5. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Kirkby, Jasper

    2001-01-01T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual e...

  6. 28th International Cosmic Ray Conference 4065 The Cosmic Ray Shadows of the Moon and the Sun De-

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    28th International Cosmic Ray Conference 4065 The Cosmic Ray Shadows of the Moon and the Sun De of the data shows that the shadows of the sun and moon have each been detected with high significances of the sun is significantly weaker than that of the moon. As expected, the measured positions of the deficits

  7. 29th International Cosmic Ray Conference Pune (2005) 2, 247250 Long-Term Modulation of the Cosmic Ray Fluctuation Spectrum

    E-Print Network [OSTI]

    Usoskin, Ilya G.

    energy-dependent difference in the solar cycle variation of cosmic ray fluctuations. 1. Introduction, there are indications that this relation may not be valid for lower energy cosmic rays of solar/interplanetary origin of Oulu, FIN-90014,Finland (c) Department of Physical Sciences, P.O.Box 3000, FIN-90014 University of Oulu

  8. Theoretical cosmic Type Ia supernova rates

    E-Print Network [OSTI]

    R. Valiante; F. Matteucci; S. Recchi; F. Calura

    2009-03-16T23:59:59.000Z

    The aim of this work is the computation of the cosmic Type Ia supernova rates at very high redshifts (z>2). We adopt various progenitor models in order to predict the number of explosions in different scenarios for galaxy formation and to check whether it is possible to select the best delay time distribution model, on the basis of the available observations of Type Ia supernovae. We also computed the Type Ia supernova rate in typical elliptical galaxies of different initial luminous masses and the total amount of iron produced by Type Ia supernovae in each case. It emerges that: it is not easy to select the best delay time distribution scenario from the observational data and this is because the cosmic star formation rate dominates over the distribution function of the delay times; the monolithic collapse scenario predicts an increasing trend of the SN Ia rate at high redshifts whereas the predicted rate in the hierarchical scheme drops dramatically at high redshift; for the elliptical galaxies we note that the predicted maximum of the Type Ia supernova rate depends on the initial galactic mass. The maximum occurs earlier (at about 0.3 Gyr) in the most massive ellipticals, as a consequence of downsizing in star formation. We find that different delay time distributions predict different relations between the Type Ia supernova rate per unit mass at the present time and the color of the parent galaxies and that bluer ellipticals present higher supernova Type Ia rates at the present time.

  9. A Dynamical Classification of the Cosmic Web

    E-Print Network [OSTI]

    J. E. Forero-Romero; Y. Hoffman; S. Gottloeber; A. Klypin; G. Yepes

    2008-09-24T23:59:59.000Z

    A dynamical classification of the cosmic web is proposed. The large scale environment is classified into four web types: voids, sheets, filaments and knots. The classification is based on the evaluation of the deformation tensor, i.e. the Hessian of the gravitational potential, on a grid. The classification is based on counting the number of eigenvalues above a certain threshold, lambda_th at each grid point, where the case of zero, one, two or three such eigenvalues corresponds to void, sheet, filament or a knot grid point. The collection of neighboring grid points, friends-of-friends, of the same web attribute constitutes voids, sheets, filaments and knots as web objects. A simple dynamical consideration suggests that lambda_th should be approximately unity, upon an appropriate scaling of the deformation tensor. The algorithm has been applied and tested against a suite of (dark matter only) cosmological N-body simulations. In particular, the dependence of the volume and mass filling fractions on lambda_th and on the resolution has been calculated for the four web types. Also, the percolation properties of voids and filaments have been studied. Our main findings are: (a) Already at lambda_th = 0.1 the resulting web classification reproduces the visual impression of the cosmic web. (b) Between 0.2 web. (c) The dynamical nature of the suggested classification provides a robust framework for incorporating environmental information into galaxy formation models, and in particular the semi-analytical ones.

  10. Alignments of Voids in the Cosmic Web

    E-Print Network [OSTI]

    Erwin Platen; Rien van de Weygaert; Bernard J. T. Jones

    2007-11-15T23:59:59.000Z

    We investigate the shapes and mutual alignment of voids in the large scale matter distribution of a LCDM cosmology simulation. The voids are identified using the novel WVF void finder technique. The identified voids are quite nonspherical and slightly prolate, with axis ratios in the order of c:b:a approx. 0.5:0.7:1. Their orientations are strongly correlated with significant alignments spanning scales >30 Mpc/h. We also find an intimate link between the cosmic tidal field and the void orientations. Over a very wide range of scales we find a coherent and strong alignment of the voids with the tidal field computed from the smoothed density distribution. This orientation-tide alignment remains significant on scales exceeding twice the typical void size, which shows that the long range external field is responsible for the alignment of the voids. This confirms the view that the large scale tidal force field is the main agent for the large scale spatial organization of the Cosmic Web.

  11. The consistency test on the cosmic evolution

    E-Print Network [OSTI]

    Gong, Yan; Zhang, Shuang-Nan; Chen, Xuelei

    2015-01-01T23:59:59.000Z

    We propose a new and robust method to test the consistency of the cosmic evolution given by a cosmological model. It is realized by comparing the combined quantity r_d^CMB/D_V^SN, which is derived from the comoving sound horizon r_d from cosmic microwave background (CMB) measurements and the effective distance D_V derived from low-redshift Type-Ia supernovae (SNe Ia) data, with direct and independent r_d/D_V obtained by baryon acoustic oscillation (BAO) measurements at median redshifts. We apply this test method for the LCDM and wCDM models, and investigate the consistency of the derived value of r_d/D_V from Planck 2015 and the SN Ia data sets of Union2.1 and JLA (z<1.5), and the r_d/D_V directly given by BAO data from six-degree-field galaxy survey (6dFGS), Sloan Digital Sky Survey Data Release 7 Main Galaxy Survey (SDSS-DR7 MGS), DR11 of SDSS-III, WiggleZ and Ly-alpha forecast surveys from Baryon Oscillation Spectroscopic Data (BOSS) DR-11 over 0.1

  12. Beam intensity upgrade at Fermilab

    SciTech Connect (OSTI)

    Marchionni, A.; /Fermilab

    2006-07-01T23:59:59.000Z

    The performance of the Fermilab proton accelerator complex is reviewed. The coming into operation of the NuMI neutrino line and the implementation of slip-stacking to increase the anti-proton production rate has pushed the total beam intensity in the Main Injector up to {approx} 3 x 10{sup 13} protons/pulse. A maximum beam power of 270 kW has been delivered on the NuMI target during the first year of operation. A plan is in place to increase it to 350 kW, in parallel with the operation of the Collider program. As more machines of the Fermilab complex become available with the termination of the Collider operation, a set of upgrades are being planned to reach first 700 kW and then 1.2 MW by reducing the Main Injector cycle time and by implementing proton stacking.

  13. Electron Ion Collider: The Next QCD Frontier - Understanding the glue that binds us all

    E-Print Network [OSTI]

    A. Accardi; J. L. Albacete; M. Anselmino; N. Armesto; E. C. Aschenauer; A. Bacchetta; D. Boer; W. K. Brooks; T. Burton; N. -B. Chang; W. -T. Deng; A. Deshpande; M. Diehl; A. Dumitru; R. Dupré; R. Ent; S. Fazio; H. Gao; V. Guzey; H. Hakobyan; Y. Hao; D. Hasch; R. Holt; T. Horn; M. Huang; A. Hutton; C. Hyde; J. Jalilian-Marian; S. Klein; B. Kopeliovich; Y. Kovchegov; K. Kumar; K. Kumeri?ki; M. A. C. Lamont; T. Lappi; J. -H. Lee; Y. Lee; E. M. Levin; F. -L. Lin; V. Litvinenko; T. W. Ludlam; C. Marquet; Z. -E. Meziani; R. McKeown; A. Metz; R. Milner; V. S. Morozov; A. H. Mueller; B. Müller; D. Müller; P. Nadel-Turonski; H. Paukkunen; A. Prokudin; V. Ptitsyn; X. Qian; J. -W. Qiu; M. Ramsey-Musolf; T. Roser; F. Sabatié; R. Sassot; G. Schnell; P. Schweitzer; E. Sichtermann; M. Stratmann; M. Strikman; M. Sullivan; S. Taneja; T. Toll; D. Trbojevic; T. Ullrich; R. Venugopalan; S. Vigdor; W. Vogelsang; C. Weiss; B. -W. Xiao; F. Yuan; Y. -H. Zhang; L. Zheng

    2014-11-30T23:59:59.000Z

    This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics and, in particular, the focused ten-week program on "Gluons and quark sea at high energies" at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them, and it benefited from inputs from the users' communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the U.S., established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.

  14. Sensitivity to light weakly-coupled new physics at the precision frontier

    E-Print Network [OSTI]

    Dall, Matthias Le; Ritz, Adam

    2015-01-01T23:59:59.000Z

    Precision measurements of rare particle physics phenomena (flavor oscillations and decays, electric dipole moments, etc.) are often sensitive to the effects of new physics encoded in higher-dimensional operators with Wilson coefficients given by ${\\rm C}/(\\Lambda_{\\rm NP})^n$, where C is dimensionless, $n\\geq 1$, and $\\Lambda_{\\rm NP}$ is an energy scale. Many extensions of the Standard Model predict that $\\Lambda_{\\rm NP} $ should be at the electroweak scale or above, and the search for new short-distance physics is often stated as the primary goal of experiments at the precision frontier. In rather general terms, we investigate the alternative possibility: ${\\rm C} \\ll 1$, and $\\Lambda_{\\rm NP} \\ll m_W$, to identify classes of precision measurements sensitive to light new physics (hidden sectors) that do not require an ultraviolet completion with additional states at or above the electroweak scale. We find that hadronic electric dipole moments, lepton number and flavor violation, non-universality, as well a...

  15. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Jasper Kirkby

    2001-04-27T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual effect on global temperatures of the burning of fossil fuels, an issue of profound importance to society. Furthermore, light radio-isotope records indicate a correlation has existed between global climate and the cosmic ray flux extending back over the present inter-glacial and perhaps earlier. This suggests it may eventually become possible to make long-term (10-1,000 year) predictions of changes in the Earth's climate, provided a deeper understanding can be achieved of the ``geomagnetic climate'' of the Sun and Earth that modulates the cosmic-ray flux.

  16. Neutrinos from gamma-ray bursts: propagation of cosmic rays in their host galaxies

    E-Print Network [OSTI]

    Wang, Zi-Yi; Wang, Jun-Feng

    2015-01-01T23:59:59.000Z

    Gamma-ray bursts (GRBs) are proposed as candidate sources of ultra-high energy cosmic rays (UHECRs). We study the possibility that the PeV neutrinos recently observed by IceCube are produced by GRB cosmic rays interacting with the interstellar gas in the host galaxies. By studying the relation between the X-ray absorption column density N_H and the surface star-formation rate of GRB host galaxies, we find that N_H is a good indicator of the surface gas density of the host galaxies. Then we are able to calculate the neutrino production efficiency of CRs for GRBs with known N_H. We collect a sample of GRBs that have both measurements of N_H and accurate gamma-ray fluence, and attempt to calculate the accumulated neutrino flux based on the current knowledge about GRBs and their host galaxies. When the CR intensity produced by GRBs is normalized with the observed UHECR flux above $10^{19}{\\rm eV}$, the accumulated neutrino flux at PeV energies is estimated to be about $(0.3\\pm0.2)\\times10^{-8} \\rm{GeV\\ cm^{-2}\\ s...

  17. Cosmic Reionization and the 21-cm signal: Comparison between an analytical model and a simulation

    E-Print Network [OSTI]

    Mario G. Santos; Alexandre Amblard; Jonathan Pritchard; Hy Trac; Renyue Cen; Asantha Cooray

    2008-08-28T23:59:59.000Z

    We measure several properties of the reionization process and the corresponding low-frequency 21-cm signal associated with the neutral hydrogen distribution, using a large volume, high resolution simulation of cosmic reionization. The brightness temperature of the 21-cm signal is derived by post-processing this numerical simulation with a semi-analytical prescription. Our study extends to high redshifts (z ~ 25) where, in addition to collisional coupling, our post-processed simulations take into account the inhomogeneities in the heating of the neutral gas by X-rays and the effect of an inhomogeneous Lya radiation field. Unlike the well-studied case where spin temperature is assumed to be significantly greater than the temperature of the cosmic microwave background due to uniform heating of the gas by X-rays, spatial fluctuations in both the Lya radiation field and X-ray intensity impact predictions related to the brightness temperature at z > 10, during the early stages of reionization and gas heating. The statistics of the 21-cm signal from our simulation are then compared to existing analytical models in the literature and we find that these analytical models provide a reasonably accurate description of the 21-cm power spectrum at z 10 and, with upcoming interferometric data, these differences in return can provide a way to better understand the astrophysical processes during reionization.

  18. Processing of formic acid-containing ice by heavy and energetic cosmic ray analogues

    E-Print Network [OSTI]

    Bergantini, A; Rothard, H; Boduch, P; Andrade, D P P

    2014-01-01T23:59:59.000Z

    Formic acid (HCOOH) has been extensively detected in space environments, including interstellar medium (gas and grains), comets and meteorites. Such environments are often subjected to the action of ionizing agents, which may cause changes in the molecular structure, thus leading to formation of new species. Formic acid is a possible precursor of pre-biotic species, such as Glycine (NH2CH2COOH). This work investigates experimentally the physicochemical effects resulting from interaction of heavy and energetic cosmic ray analogues (46MeV 58Ni11+) in H2O:HCOOH (1:1) ice, at 15 K, in ultrahigh vacuum regime, using Fourier transform infrared spectrometry in the mid-infrared region (4000-600 cm-1 or 2.5-12.5 microns). After the bombardment, the sample was slowly heated to room temperature. The results show the dissociation cross-section for the formic acid of 2.4x10^-13 cm2, and half-life due to galactic cosmic rays of 8x10^7 yr. The IR spectra show intense formation of CO and CO2, and small production of more com...

  19. Cosmic Ray Acceleration at Relativistic Shocks

    E-Print Network [OSTI]

    Michal Ostrowski

    2003-10-29T23:59:59.000Z

    Theoretical studies of cosmic ray particle acceleration in the first-order Fermi process at relativistic shocks are reviewed. At the beginning we discuss the acceleration processes acting at mildly relativistic shock waves. An essential role of oblique field configurations and field perturbations in forming the particle energy spectrum and changing the acceleration time scale is discussed. Then, we report on attempts to consider particle acceleration at ultra-relativistic shocks, often yielding an asymptotic spectral index sigma = 2.2 at large shock Lorentz factors. We explain why this result is limited to the cases of highly turbulent conditions near shocks. We conclude that our present knowledge of the acceleration processes acting at relativistic shocks is insufficient to allow for realistic modelling of the real shocks. The present review is a modified, extended and updated version of Ostrowski (1999).

  20. Dark Energy Generated by Warped Cosmic Strings

    E-Print Network [OSTI]

    Reinoud Jan Slagter

    2014-07-29T23:59:59.000Z

    If we live on the weak brane in a warped 5D bulk spacetime, gravitational waves and brane fluctuations can be generated by a part of the 5D Weyl tensor and carries information of the gravitational field outside the brane. We consider the U(1) self-gravitating scalar-gauge field on the warped spacetime without bulk matter. It turns out that "branons" can be formed dynamically, due to the modified energy-momentum tensor components of the cosmic string. It turns out that the parameter $\\alpha$, i.e., the gauge-to-scalar mass, changes from a value $>1$ to a value $wave energy. It is the time-dependent part of the warp factor which triggers this extraordinary behavior.

  1. Muon Acceleration in Cosmic-ray Sources

    E-Print Network [OSTI]

    Spencer R. Klein; Rune Mikkelsen; Julia K. Becker Tjus

    2012-08-09T23:59:59.000Z

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

  2. Muon acceleration in cosmic-ray sources

    SciTech Connect (OSTI)

    Klein, Spencer R.; Mikkelsen, Rune E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Becker Tjus, Julia [Fakultät für Physik and Astronomie, Theoretische Physik I, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2013-12-20T23:59:59.000Z

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in gamma-ray bursts, magnetars, or other sources. These transient sources have short lifetimes, which necessitate very high accelerating gradients, up to 10{sup 13} keV cm{sup –1}. At gradients above 1.6 keV cm{sup –1}, muons produced by hadronic interactions undergo significant acceleration before they decay. This muon acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. Using the IceCube high-energy diffuse neutrino flux limits, we set two-dimensional limits on the source opacity and matter density, as a function of accelerating gradient. These limits put strong constraints on different models of particle acceleration, particularly those based on plasma wake-field acceleration, and limit models for sources like gamma-ray bursts and magnetars.

  3. The `excess' of primary cosmic ray electrons

    E-Print Network [OSTI]

    Xiang Li; Zhao-Qiang Shen; Bo-Qiang Lu; Tie-Kuang Dong; Yi-Zhong Fan; Lei Feng; Si-Ming Liu; Jin Chang

    2014-12-04T23:59:59.000Z

    With the accurate cosmic ray (CR) electron and positron spectra (denoted as $\\Phi_{\\rm e^{-}}$ and $\\Phi_{\\rm e^{+}}$, respectively) measured by AMS-02 collaboration, the difference between the electron and positron fluxes (i.e., $\\Delta \\Phi=\\Phi_{\\rm e^{-}}-\\Phi_{\\rm e^{+}}$), dominated by the propagated primary electrons, can be reliably inferred. In the standard model, the spectrum of propagated primary CR electrons at energies $\\geq 30$ GeV softens with the increase of energy. The absence of any evidence for such a continuous spectral softening in $\\Delta \\Phi$ strongly suggests a significant `excess' of primary CR electrons and at energies of $100-400$ GeV the identified excess component has a flux comparable to that of the observed positron excess. Middle-age but `nearby' supernova remnants (e.g., Monogem and Geminga) are favored sources for such an excess.

  4. The SDSS Coadd: Cosmic Shear Measurement

    SciTech Connect (OSTI)

    Lin, Huan; /Fermilab; Dodelson, Scott; /Fermilab /Chicago U., EFI /Chicago U., KICP; Seo, Hee-Jong; /UC, Berkeley; Soares-Santos, Marcelle; /Fermilab; Annis, James; /Fermilab; Hao, Jiangang; /Fermilab; Johnston, David; /Fermilab; Kubo, Jeffrey M.; /Fermilab; Reis, Ribamar R.R.; /Fermilab /Rio de Janeiro Federal U.; Simet, Melanie; /Chicago U., EFI /Chicago U., KICP

    2011-11-01T23:59:59.000Z

    Stripe 82 in the Sloan Digital Sky Survey was observed multiple times, allowing deeper images to be constructed by coadding the data. Here we analyze the ellipticities of background galaxies in this 275 square degree region, searching for evidence of distortions due to cosmic shear. The E-mode is detected in both real and Fourier space with > 5-{sigma} significance on degree scales, while the B-mode is consistent with zero as expected. The amplitude of the signal constrains the combination of the matter density {Omega}{sub m} and fluctuation amplitude {sigma}{sub 8} to be {Omega}{sub m}{sup 0.7} {sigma}{sub 8} = 0.276{sub -0.050}{sup +0.036}.

  5. Cosmic-ray positrons from millisecond pulsars

    E-Print Network [OSTI]

    Venter, C; Harding, A K; Gonthier, P L; Büsching, I

    2015-01-01T23:59:59.000Z

    Observations by the Fermi Large Area Telescope of gamma-ray millisecond pulsar light curves imply copious pair production in their magnetospheres, and not exclusively in those of younger pulsars. Such pair cascades may be a primary source of Galactic electrons and positrons, contributing to the observed enhancement in positron flux above ~10 GeV. Fermi has also uncovered many new millisecond pulsars, impacting Galactic stellar population models. We investigate the contribution of Galactic millisecond pulsars to the flux of terrestrial cosmic-ray electrons and positrons. Our population synthesis code predicts the source properties of present-day millisecond pulsars. We simulate their pair spectra invoking an offset-dipole magnetic field. We also consider positrons and electrons that have been further accelerated to energies of several TeV by strong intrabinary shocks in black widow and redback systems. Since millisecond pulsars are not surrounded by pulsar wind nebulae or supernova shells, we assume that the p...

  6. Lyman Alpha Absorption in The Cosmic Web

    E-Print Network [OSTI]

    J. Richard Bond; James W. Wadsley

    1997-10-10T23:59:59.000Z

    We describe large scale structure at high redshift in terms of the Cosmic Web picture for {S,Lambda,O,H}CDM models: how galactic-scale ``peak-patches'', filaments and membranes create an interconnected intergalactic medium. The ideas are applied to our Ly$\\alpha$ forest simulations of ``shear-field patches''. We discuss simulation method and design, resolution dependence, the statistical combination of patches, UV flux scaling, and whether filtered Zel'dovich maps are useful. The response to changes in power spectrum shape and amplitude, and in cosmological parameters, is described. We also show Omega_b h^2 derived from UV rescaling is overestimated if the resolution is not adequate.

  7. The Cosmic Battery in Astrophysical Accretion Disks

    E-Print Network [OSTI]

    Contopoulos, Ioannis; Katsanikas, Matthaios

    2015-01-01T23:59:59.000Z

    The aberrated radiation pressure at the inner edge of the accretion disk around an astrophysical black hole imparts a relative azimuthal velocity on the electrons with respect to the ions which gives rise to a ring electric current that generates large scale poloidal magnetic field loops. This is the Cosmic Battery established by Contopoulos and Kazanas in 1998. In the present work we perform realistic numerical simulations of this important astrophysical mechanism in advection-dominated accretion flows-ADAF. We confirm the original prediction that the inner parts of the loops are continuously advected toward the central black hole and contribute to the growth of the large scale magnetic field, whereas the outer parts of the loops are continuously diffusing outward through the turbulent accretion flow. This process of inward advection of the axial field and outward diffusion of the return field proceeds all the way to equipartition, thus generating astrophysically significant magnetic fields on astrophysicall...

  8. Transition from galactic to extragalactic cosmic rays

    E-Print Network [OSTI]

    V. Berezinsky

    2007-10-20T23:59:59.000Z

    The transition from galactic to extragalactic cosmic rays is discussed. One of critical indications for transition is given by the Standard Model of Galactic cosmic rays, according to which the maximum energy of acceleration for iron nuclei is of order of $E_{\\rm Fe}^{\\rm max} \\approx 1\\times 10^{17}$ eV. At $E > E_{\\rm Fe}^{\\rm max}$ the spectrum is predicted to be very steep and thus the Standard Model favours the transition at energy not much higher than $E_{\\rm Fe}^{\\rm max}$. As observations are concerned there are two signatures of transition: change of energy spectra and elongation rate (depth of shower maximum in the atmosphere $X_{\\rm max}$ as function of energy). Three models of transition are discussed: dip-based model, mixed composition model and ankle model. In the latter model the transition occurs at the observed spectral feature, ankle, which starts at $E_a \\approx 1\\times 10^{19}$ eV and is characterised by change of mass compostion from galactic iron to extragalactic protons. In the dip model the transition occures at the second knee observed at energy $(4 -8)\\times 10^{17}$ eV and is characterised by change of mass composition from galactic iron to extragalactic protons. The mixed composition model describes transition at $E \\sim 3\\times 10^{18}$ eV with mass composition changing from galactic iron to extragactic mixed composition of different nuclei. These models are confronted with observational data on spectra and elongation rates from different experiments, including Auger.

  9. The Fluid Interface Reactions Structures and Transport (FIRST) EFRC (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    SciTech Connect (OSTI)

    Wesolowski, David J. (Director, FIRST - Fluid Interface Reactions, Structures, and Transport Center) [Director, FIRST - Fluid Interface Reactions, Structures, and Transport Center; FIRST Staff

    2011-05-01T23:59:59.000Z

    'The Fluid Interface Reactions Structures and Transport (FIRST) EFRC' was submitted by FIRST to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. FIRST, an EFRC directed by David J. Wesolowski at the Oak Ridge National Laboratory is a partnership of scientists from nine institutions: Oak Ridge National Laboratory (lead), Argonne National Laboratory, Drexel University, Georgia State University, Northwestern University, Pennsylvania State University, Suffolk University, Vanderbilt University, and University of Virginia. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of Fluid Interface Reactions, Structures and Transport Center is 'to develop quantitative and predictive models of the unique nanoscale environment at fluid-solid interfaces that will enable transformational advances in electrical energy storage and heterogeneous catalysis for solar fuels.' Research topics are: catalysis (biomass, CO{sub 2}, water), electrocatalysis, photocatalysis, photoelectrocatalysis, solar fuels, solar electrodes, electrical energy storage, batteries, capacitors, battery electrodes, electrolytes, extreme environment, CO{sub 2} (convert), greenhouse gas, microelectromechanical systems (MEMS), interfacial characterization, matter by design, novel materials synthesis, and charge transport.

  10. The Fluid Interface Reactions Structures and Transport (FIRST) EFRC (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Wesolowski, David J. (Director, FIRST - Fluid Interface Reactions, Structures, and Transport Center); FIRST Staff

    2011-11-02T23:59:59.000Z

    'The Fluid Interface Reactions Structures and Transport (FIRST) EFRC' was submitted by FIRST to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. FIRST, an EFRC directed by David J. Wesolowski at the Oak Ridge National Laboratory is a partnership of scientists from nine institutions: Oak Ridge National Laboratory (lead), Argonne National Laboratory, Drexel University, Georgia State University, Northwestern University, Pennsylvania State University, Suffolk University, Vanderbilt University, and University of Virginia. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of Fluid Interface Reactions, Structures and Transport Center is 'to develop quantitative and predictive models of the unique nanoscale environment at fluid-solid interfaces that will enable transformational advances in electrical energy storage and heterogeneous catalysis for solar fuels.' Research topics are: catalysis (biomass, CO{sub 2}, water), electrocatalysis, photocatalysis, photoelectrocatalysis, solar fuels, solar electrodes, electrical energy storage, batteries, capacitors, battery electrodes, electrolytes, extreme environment, CO{sub 2} (convert), greenhouse gas, microelectromechanical systems (MEMS), interfacial characterization, matter by design, novel materials synthesis, and charge transport.

  11. Cosmic microwave background constraints on dark energy dynamics: analysis beyond the power spectrum

    E-Print Network [OSTI]

    Fabio Giovi; Carlo Baccigalupi; Francesca Perrotta

    2005-05-18T23:59:59.000Z

    We consider the distribution of the non-Gaussian signal induced by weak lensing on the primary total intensity cosmic microwave background (CMB) anisotropies. Our study focuses on the three point statistics exploiting an harmonic analysis based on the CMB bispectrum. By considering the three multipoles as independent variables, we reveal a complex structure of peaks and valleys determined by the re-projection of the primordial acoustic oscillations through the lensing mechanism. We study the dependence of this system on the expansion rate at the epoch in which the weak lensing power injection is relevant, probing the dark energy equation of state at redshift corresponding to the equivalence with matter or higher ($w_\\infty$). We evaluate the impact of the bispectrum observable on the CMB capability of constraining the dark energy dynamics. We perform a maximum likelihood analysis by varying the dark energy abundance, the present equation of state $w_0$ and $w_\\infty$. We show that the projection degeneracy affecting a pure power spectrum analysis in total intensity is broken if the bispectrum is taken into account. For a Planck-like experiment, assuming nominal performance, no foregrounds or systematics, and fixing all the parameters except $w_0$, $w_\\infty$ and the dark energy abundance, a percent and ten percent precision measure of $w_0$ and $w_\\infty$ is achievable from CMB data only. These results indicate that the detection of the weak lensing signal by the forthcoming CMB probes may be relevant to gain insight into the dark energy dynamics at the onset of cosmic acceleration.

  12. TeV Blazars and Cosmic Infrared Background Radiation

    E-Print Network [OSTI]

    F. A. Aharonian

    2001-12-13T23:59:59.000Z

    The recent developments in studies of TeV radiation from blazars are highlighted and the implications of these results for derivation of cosmologically important information about the cosmic infrared background radiation are discussed.

  13. Doctoral Thesis in Physics Measurements of cosmic ray antiprotons

    E-Print Network [OSTI]

    Haviland, David

    of propagation models Juan Wu Particle and Astroparticle Physics, Department of Physics, Royal Institute such as dark matter. To understand cosmic ray accel- eration and propagation mechanisms, accurate measurements

  14. Cosmic Web and Environmental Dependence of Screening: Vainshtein vs. Chameleon

    E-Print Network [OSTI]

    Falck, Bridget; Zhao, Gong-bo

    2015-01-01T23:59:59.000Z

    Theories which modify general relativity to explain the accelerated expansion of the Universe often use screening mechanisms to satisfy constraints on Solar System scales. We investigate the effects of the cosmic web and the local environmental density of dark matter halos on the screening properties of the Vainshtein and chameleon screening mechanisms. We compare the cosmic web morphology of dark matter particles, mass functions of dark matter halos, mass and radial dependence of screening, velocity dispersions and peculiar velocities, and environmental dependence of screening mechanisms in $f(R)$ and nDGP models. Using the ORIGAMI cosmic web identification routine we find that the Vainshtein mechanism depends on the cosmic web morphology of dark matter particles, since these are defined according to the dimensionality of their collapse, while the chameleon mechanism shows no morphology dependence. The chameleon screening of halos and their velocity dispersions depend on halo mass, and small halos and subhal...

  15. A Quantum Phase Transition in the Cosmic Ray Energy Distribution

    E-Print Network [OSTI]

    Widom, A; Srivastava, Y

    2015-01-01T23:59:59.000Z

    We here argue that the "knee" of the cosmic ray energy distribution at $E_c \\sim 1$ PeV represents a second order phase transition of cosmic proportions. The discontinuity of the heat capacity per cosmic ray particle is given by $\\Delta c=0.450196\\ k_B$. However the idea of a deeper critical point singularity cannot be ruled out by present accuracy in neither theory nor experiment. The quantum phase transition consists of cosmic rays dominated by bosons for the low temperature phase E E_c$. The low temperature phase arises from those nuclei described by the usual and conventional collective boson models of nuclear physics. The high temperature phase is dominated by protons. The transition energy $E_c$ may be estimated in terms of the photo-disintegration of nuclei.

  16. Bulk Viscosity, Decaying Dark Matter, and the Cosmic Acceleration

    E-Print Network [OSTI]

    James R. Wilson; Grant J. Mathews; George M. Fuller

    2006-09-25T23:59:59.000Z

    We discuss a cosmology in which cold dark-matter particles decay into relativistic particles. We argue that such decays could lead naturally to a bulk viscosity in the cosmic fluid. For decay lifetimes comparable to the present hubble age, this bulk viscosity enters the cosmic energy equation as an effective negative pressure. We investigate whether this negative pressure is of sufficient magnitude to account fo the observed cosmic acceleration. We show that a single decaying species in a flat, dark-matter dominated cosmology without a cosmological constant cannot reproduce the observed magnitude-redshift relation from Type Ia supernovae. However, a delayed bulk viscosity, possibly due to a cascade of decaying particles may be able to account for a significant fraction of the apparent cosmic acceleration. Possible candidate nonrelativistic particles for this scenario include sterile neutrinos or gauge-mediated decaying supersymmetric particles.

  17. Towards a metamaterial simulation of a spinning cosmic string

    E-Print Network [OSTI]

    Tom G. Mackay; Akhlesh Lakhtakia

    2009-11-21T23:59:59.000Z

    Establishing the constitutive parameters of a nonhomogeneous bianisotropic medium that is equivalent to the spacetime metric of a spinning cosmic string, in a noncovariant formalism, we found a metamaterial route to investigate the existence of closed timelike curves.

  18. Cosmic ray lithium isotope measurement with AMS-01

    E-Print Network [OSTI]

    Zhou, Feng, Ph. D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    The AMS-01 detector measured charged cosmic rays during 10 days on the Space Shuttle Discovery in 1998 and collected 108 events. By identifying 8349 Lithium and 22709 Carbon nuclei from the raw data, this thesis presents ...

  19. Energy Intensity Baselining and Tracking Guidance

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Learn more at betterbuildings.energy.gov Energy Intensity Baselining and Tracking Guidance i Preface The U.S. Department of Energy's (DOE's) Better Buildings, Better Plants Program...

  20. Energy Frontier Research Center, Center for Materials Science of Nuclear Fuels

    SciTech Connect (OSTI)

    Todd R. Allen, Director

    2011-04-01T23:59:59.000Z

    The Office of Science, Basic Energy Sciences, has funded the INL as one of the Energy Frontier Research Centers in the area of material science of nuclear fuels. This document is the required annual report to the Office of Science that outlines the accomplishments for the period of May 2010 through April 2011. The aim of the Center for Material Science of Nuclear Fuels (CMSNF) is to establish the foundation for predictive understanding of the effects of irradiation-induced defects on thermal transport in oxide nuclear fuels. The science driver of the center’s investigation is to understand how complex defect and microstructures affect phonon mediated thermal transport in UO2, and achieve this understanding for the particular case of irradiation-induced defects and microstructures. The center’s research thus includes modeling and measurement of thermal transport in oxide fuels with different levels of impurities, lattice disorder and irradiation-induced microstructure, as well as theoretical and experimental investigation of the evolution of disorder, stoichiometry and microstructure in nuclear fuel under irradiation. With the premise that thermal transport in irradiated UO2 is a phonon-mediated energy transport process in a crystalline material with defects and microstructure, a step-by-step approach will be utilized to understand the effects of types of defects and microstructures on the collective phonon dynamics in irradiated UO2. Our efforts under the thermal transport thrust involved both measurement of diffusive phonon transport (an approach that integrates over the entire phonon spectrum) and spectroscopic measurements of phonon attenuation/lifetime and phonon dispersion. Our distinct experimental efforts dovetail with our modeling effort involving atomistic simulation of phonon transport and prediction of lattice thermal conductivity using the Boltzmann transport framework.

  1. Energy Frontier Research Centers: A View from Senior EFRC Representatives (2011 EFRC Summit, panel session)

    ScienceCinema (OSTI)

    Drell, Persis (SLAC); Armstrong, Neal (University of Arizona); Carter, Emily (Princeton University); DePaolo, Don (Lawrence Berkeley National Laboratory); Gunnoe, Brent (University of Virginia)

    2012-03-16T23:59:59.000Z

    A distinguished panel of scientists from the EFRC community provide their perspective on the importance of EFRCs for addressing critical energy needs at the 2011 EFRC Summit. Persis Drell, Director at SLAC, served as moderator. Panel members are Neal Armstrong (Director of the Center for Interface Science: Solar Electric Materials, led by the University of Arizona), Emily Carter (Co-Director of the Combustion EFRC, led by Princeton University. She is also Team Leader of the Heterogeneous Functional Materials Center, led by the University of South Caroline), Don DePaolo (Director of the Center for Nanoscale Control of Geologic CO2, led by LBNL), and Brent Gunnoe (Director of the Center for Catalytic Hydrocarbon Functionalization, led by the University of Virginia). The 2011 EFRC Summit and Forum brought together the EFRC community and science and policy leaders from universities, national laboratories, industry and government to discuss "Science for our Nation's Energy Future." In August 2009, the Office of Science established 46 Energy Frontier Research Centers. The EFRCs are collaborative research efforts intended to accelerate high-risk, high-reward fundamental research, the scientific basis for transformative energy technologies of the future. These Centers involve universities, national laboratories, nonprofit organizations, and for-profit firms, singly or in partnerships, selected by scientific peer review. They are funded at $2 to $5 million per year for a total planned DOE commitment of $777 million over the initial five-year award period, pending Congressional appropriations. These integrated, multi-investigator Centers are conducting fundamental research focusing on one or more of several ?grand challenges? and use-inspired ?basic research needs? recently identified in major strategic planning efforts by the scientific community. The purpose of the EFRCs is to integrate the talents and expertise of leading scientists in a setting designed to accelerate research that transforms the future of energy and the environment.

  2. Frontiers in Microbiology: Envisioning a Curriculum Unit for High School Biology

    SciTech Connect (OSTI)

    Mark Bloom

    2004-06-18T23:59:59.000Z

    Microbiology is undergoing a quiet revolution. Techniques such as polymerase chain reaction, high throughput DNA sequencing, whole genome shotgun sequencing, DNA microarrays, and bioinformatics analyses are greatly aiding our understanding of the estimated one billion species of microbes that inhabit the Earth. Unfortunately, the rapid pace of research in microbiology stands in contrast to the much slower pace of change in educational reform. Biological Sciences Curriculum Study (BSCS) hosted a two-day planning meeting to discuss whether or not a new curriculum unit on microbiology is desirable for the high school audience. Attending the meeting were microbiologists, high school biology teachers, and science educators. The consensus of the participants was that an inquiry-based unit dealing with advances in microbiology should be developed for a high school biology audience. Participants established content priorities for the unit, discussed the unit's conceptual flow, brainstormed potential student activities, and discussed the role of educational technology for the unit. As a result of the planning meeting discussions, BSCS staff sought additional funding to develop, disseminate, and evaluate the Frontiers in Microbiology curriculum unit. This unit was intended to be developed as a replacement unit suitable for an introductory biology course. The unit would feature inquiry-based student activities and provide approximately four weeks of instruction. As appropriate, activities would make use of multimedia. The development and production processes would require about two years for completion. Unfortunately, BSCS staff was not able to attract sufficient funding to develop the proposed curriculum unit. Since there were some unexpended funds left over from the planning meeting, BSCS requested and received permission from DOE to use the balance of the funds to prepare background materials about advances in microbiology that would be useful to teachers. These materials were developed and placed on the BSCS Web site (http://www.bscs.org).

  3. High Energy Neutrino Astronomy - the cosmic-ray connection

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2000-11-28T23:59:59.000Z

    Several of the models for origin of the highest energy cosmic rays also predict significant neutrino fluxes. A common factor of the models is that they must provide sufficient power to supply the observed energy in the extragalactic component of the cosmic radiation. The assumption that a comparable amount of energy goes into high-energy neutrinos allows a model-independent estimate of the neutrino signal that may be expected.

  4. The HAWC Gamma-Ray Observatory: Observations of Cosmic Rays

    E-Print Network [OSTI]

    Abeysekara, A U; Alvarez, C; Álvarez, J D; Arceo, R; Arteaga-Velázquez, J C; Solares, H A Ayala; Barber, A S; Baughman, B M; Bautista-Elivar, N; Belmont, E; BenZvi, S Y; Berley, D; Rosales, M Bonilla; Braun, J; Caballero-Lopez, R A; Caballero-Mora, K S; Carramiñana, A; Castillo, M; Cotti, U; Cotzomi, J; de la Fuente, E; De León, C; DeYoung, T; Hernandez, R Diaz; Díaz-Vélez, J C; Dingus, B L; DuVernois, M A; Ellsworth, R W; Fernandez, A; Fiorino, D W; Fraija, N; Galindo, A; Garfias, F; González, L X; González, M M; Goodman, J A; Grabski, V; Gussert, M; Hampel-Arias, Z; Hui, C M; Hüntemeyer, P; Imran, A; Iriarte, A; Karn, P; Kieda, D; Kunde, G J; Lara, A; Lauer, R J; Lee, W H; Lennarz, D; Vargas, H León; Linares, E C; Linnemann, J T; Longo, M; Luna-GarcIa, R; Marinelli, A; Martinez, H; Martinez, O; Martínez-Castro, J; Matthews, J A J; Miranda-Romagnoli, P; Moreno, E; Mostafá, M; Nava, J; Nellen, L; Newbold, M; Noriega-Papaqui, R; Oceguera-Becerra, T; Patricelli, B; Pelayo, R; Pérez-Pérez, E G; Pretz, J; Rivière, C; Rosa-González, D; Salazar, H; Salesa, F; Sanchez, F E; Sandoval, A; Santos, E; Schneider, M; Silich, S; Sinnis, G; Smith, A J; Sparks, K; Springer, R W; Taboada, I; Toale, P A; Tollefson, K; Torres, I; Ukwatta, T N; Villaseñor, L; Weisgarber, T; Westerhoff, S; Wisher, I G; Wood, J; Yodh, G B; Younk, P W; Zaborov, D; Zepeda, A; Zhou, H

    2013-01-01T23:59:59.000Z

    We describe measurements of GeV and TeV cosmic rays with the High-Altitude Water Cherenkov Gamma-Ray Observatory, or HAWC. The measurements include the observation of the shadow of the moon; the observation of small-scale and large-scale angular clustering of the TeV cosmic rays; the prospects for measurement of transient solar events with HAWC; and the observation of Forbush decreases with the HAWC engineering array and HAWC-30.

  5. Constraints on the Cosmic Rays in the Small Magellanic Cloud

    E-Print Network [OSTI]

    Arnon Dar; Ari Laor; Abraham Loeb

    1993-02-25T23:59:59.000Z

    We show that recent $\\gamma$-ray observations of the Small Magellanic Cloud with EGRET rule out a universal cosmic ray flux only at energies below $\\approx 10$ GeV, while the observed diffuse X-ray and $\\gamma$-ray background radiations have already ruled out, by more than three orders of magnitude, a universal extragalactic cosmic ray flux identical to that observed in the local solar neighborhood at energies below $10^6$ GeV.

  6. Gauge-flation and Cosmic No-Hair Conjecture

    E-Print Network [OSTI]

    A. Maleknejad; M. M. Sheikh-Jabbari; Jiro Soda

    2011-10-06T23:59:59.000Z

    Gauge-flation, inflation from non-Abelian gauge fields, was introduced in [1,2]. In this work, we study the cosmic no-hair conjecture in gauge-flation. Starting from Bianchi-type I cosmology and through analytic and numeric studies we demonstrate that the isotropic FLRW inflation is an attractor of the dynamics of the theory and that the anisotropies are damped within a few e-folds, in accord with the cosmic no-hair conjecture.

  7. 32ND INTERNATIONAL COSMIC RAY CONFERENCE, BEIJING 2011 Solar modulation of cosmic rays since 1936: Neutron monitors and balloon-borne data

    E-Print Network [OSTI]

    Usoskin, Ilya G.

    32ND INTERNATIONAL COSMIC RAY CONFERENCE, BEIJING 2011 Solar modulation of cosmic rays since 1936¨a Geophysical Observatory, University of Oulu, Finland 2 Lebedev Physical Institute, Russian Academy of Sciences used to parameterize the energy spectrum of galactic cosmic rays, for the period from July 1936 through

  8. High intensity performance of the Brookhaven AGS

    SciTech Connect (OSTI)

    Brennan, J.M.; Roser, T.

    1996-07-01T23:59:59.000Z

    Experience and results from recent high intensity proton running periods of the Brookhaven AGS, during which a record intensity for a proton synchrotron of 6.3 x 10{sup 13} protons/pulse was reached, is presented. This high beam intensity allowed for the simultaneous operation of three high precision rare kaon decay experiments. The record beam intensities were achieved after the 1.5 GeV Booster was commissioned and a transition jump system, a powerful transverse damper, and an rf upgrade in the AGS were completed. Recently even higher intensity proton synchrotrons are studied for neutron spallation sources or proton driver for a muon collider. Implications of the experiences from the AGS to these proposals and also possible future upgrades for the AGS are discussed.

  9. On the Electrodynamics of Cosmic repulsion

    E-Print Network [OSTI]

    Howard D. Greyber

    2005-09-08T23:59:59.000Z

    Applying the known physics of plasmas, the 40 plus year old "Strong" Magnetic Field (SMF) model has been extended from explaining the nature of the AGN/quasar central engine, the evolution of galaxies, quasars and jets, the origin of large-scale magnetic fields and large-scale structure of galaxies in our Big Bang Universe, to explaining cosmic repulsion and why it overcame the influence of Gravity only about five billion years ago. Well-known facts about Einstein's general relativity equations, together with the SMF model, are used to explain the astronomical observations that forced us to deduce a present acceleration of the expansion of the Universe. Two groups of astronomical observers, one headed by Saul Perlmutter and the other by Robert Kirshner, recently found an amazing transition, from the expected slowing of the expansion of the Universe due to Gravity, to the expansion of the Universe beginning to be accelerated, at about an age of the Universe of nine billion years in our Big Bang Universe. Profound questions that arise are: what is this "dark energy" causing this result, and why has it started to overcome attractive gravity only in the last five billion years of our 14 billion year old Universe.

  10. Cosmic Microwave Background Anisotropy Window Functions Revisited

    E-Print Network [OSTI]

    Lloyd Knox

    1999-09-28T23:59:59.000Z

    The primary results of most observations of cosmic microwave background (CMB) anisotropy are estimates of the angular power spectrum averaged through some broad band, called band-powers. These estimates are in turn what are used to produce constraints on cosmological parameters due to all CMB observations. Essential to this estimation of cosmological parameters is the calculation of the expected band-power for a given experiment, given a theoretical power spectrum. Here we derive the "band power" window function which should be used for this calculation, and point out that it is not equivalent to the window function used to calculate the variance. This important distinction has been absent from much of the literature: the variance window function is often used as the band-power window function. We discuss the validity of this assumed equivalence, the role of window functions for experiments that constrain the power in {\\it multiple} bands, and summarize a prescription for reporting experimental results. The analysis methods detailed here are applied in a companion paper to three years of data from the Medium Scale Anisotropy Measurement.

  11. The Vainshtein Mechanism in the Cosmic Web

    E-Print Network [OSTI]

    Bridget Falck; Kazuya Koyama; Gong-bo Zhao; Baojiu Li

    2014-08-01T23:59:59.000Z

    We investigate the dependence of the Vainshtein screening mechanism on the cosmic web morphology of both dark matter particles and halos as determined by ORIGAMI. Unlike chameleon and symmetron screening, which come into effect in regions of high density, Vainshtein screening instead depends on the dimensionality of the system, and screened bodies can still feel external fields. ORIGAMI is well-suited to this problem because it defines morphologies according to the dimensionality of the collapsing structure and does not depend on a smoothing scale or density threshold parameter. We find that halo particles are screened while filament, wall, and void particles are unscreened, and this is independent of the particle density. However, after separating halos according to their large scale morphological environment, we find no difference in the screening properties of halos in filaments versus halos in clusters. We find that the fifth force enhancement of dark matter particles in halos is greatest well outside the virial radius. We confirm the theoretical expectation that even if the internal field is suppressed by the Vainshtein mechanism, the object still feels the fifth force generated by the external fields, by measuring peculiar velocities and velocity dispersions of halos. Finally, we investigate the morphology and gravity model dependence of halo spins, concentrations, and shapes.

  12. Cosmic axion background propagation in galaxies

    E-Print Network [OSTI]

    Day, Francesca V

    2015-01-01T23:59:59.000Z

    Many extensions of the Standard Model include axions or axion-like particles (ALPs). Here we study ALP to photon conversion in the magnetic field of the Milky Way and starburst galaxies. By modelling the effects of the coherent and random magnetic fields, the warm ionized medium and the warm neutral medium on the conversion process, we simulate maps of the conversion probability across the sky for a range of ALP energies. In particular, we consider a diffuse cosmic ALP background (CAB) analogous to the CMB, whose existence is suggested by string models of inflation. ALP-photon conversion of a CAB in the magnetic fields of galaxy clusters has been proposed as an explanation of the cluster soft X-ray excess. We therefore study the phenomenology and expected photon signal of CAB propagation in the Milky Way. We find that, for the CAB parameters required to explain the cluster soft X-ray excess, the photon flux from ALP-photon conversion in the Milky Way would be unobservably small. The ALP-photon conversion prob...

  13. Quasar H II Regions During Cosmic Reionization

    E-Print Network [OSTI]

    Marcelo A. Alvarez; Tom Abel

    2007-09-10T23:59:59.000Z

    Cosmic reionization progresses as HII regions form around sources of ionizing radiation. Their average size grows continuously until they percolate and complete reionization. We demonstrate how this typical growth can be calculated around the largest, biased sources of UV emission, such as quasars, by further developing an analytical model based on the excursion set formalism. This approach allows us to calculate the sizes and growth of the HII regions created by the progenitors of any dark matter halo of given mass and redshift with a minimum of free parameters. Statistical variations in the size of these pre-existing HII regions are an additional source of uncertainty in the determination of very high redshift quasar properties from their observed HII region sizes. We use this model to demonstrate that the transmission gaps seen in very high redshift quasars can be understood from the radiation of only their progenitors and associated clustered small galaxies. The fit sets a lower limit on the redshift of overlap at z = 5.8 +/- 0.1. This interpretation makes the transmission gaps independent of the age of the quasars observed. If this interpretation were correct it would raise the prospects of using radio interferometers currently under construction to detect the epoch of reionization.

  14. Morphological Statistics of the Cosmic Web

    E-Print Network [OSTI]

    Sergei F. Shandarin

    2004-05-28T23:59:59.000Z

    We report the {\\em first} systematic study of the supercluster-void network in the $\\Lambda$CDM concordance cosmology treating voids and superclusters on an equal footing. We study the dark matter density field in real space smoothed with the $L_s = 5$ \\hm1 Mpc Gaussian window. Superclusters and voids are defined as individual members of over-dense and under-dense excursion sets respectively. We determine the morphological properties of the cosmic web at a large number of dark matter density levels by computing Minkowski functionals for every supercluster and void. At the adopted smoothing scale individual superclusters totally occupy no more than about 5% of the total volume and contain no more than 20% of mass if the largest supercluster is excluded. Likewise, individual voids totally occupy no more than 14% of volume and contain no more than 4% of mass if the largest void is excluded. The genus of individual superclusters can be $\\sim 5$ while the genus of individual voids reaches $\\sim 55$, implying significant amount of substructure in superclusters and especially in voids. Large voids are typically distinctly non-spherical.

  15. Expansion and Collapse in the Cosmic Web

    E-Print Network [OSTI]

    Michael Rauch; George D. Becker; Matteo Viel; Wallace L. W. Sargent; Alain Smette; Robert A. Simcoe; Thomas A. Barlow; Martin G. Haehnelt

    2005-09-09T23:59:59.000Z

    We study the kinematics of the gaseous cosmic web at high redshift with Lyman alpha forest absorption in multiple QSO sightlines. Using a simple analytic model and a cosmological hydrodynamic simulation we constrain the underlying three-dimensional distribution of velocities from the observed line-of-sight distribution of velocity shear across the plane of the sky. The distribution is found to be in good agreement with the intergalactic medium (IGM) undergoing large scale motions dominated by the Hubble flow. Modeling the Lyman alpha clouds analytically and with a hydrodynamics simulation, the average expansion velocity of the gaseous structures causing the Lyman alpha forest in the lower redshift (z = 2) sample appears about 20 percent lower than the local Hubble expansion velocity. We interpret this as tentative evidence for some clouds undergoing gravitational collapse. However, the distribution of velocities is highly skewed, and the majority of clouds at redshifts from 2 to 3.8 expand typically about 5 - 20 percent faster than the Hubble flow. This behavior is explained if most absorbers in the column density range typically detectable are expanding filaments that stretch and drain into more massive nodes. We find no evidence for the observed distribution of velocity shear being significantly influenced by processes other than Hubble expansion and gravitational instability, like galactic winds. To avoid overly disturbing the IGM, winds may be old and/or limp by the time we observe them in the Lyman alpha forest, or they may occupy only an insignificant volume fraction of the IGM. (abridged)

  16. ISO and the Cosmic Infrared Background

    E-Print Network [OSTI]

    Herve Dole

    2002-12-12T23:59:59.000Z

    ISO observed, for the first time to such a high sensitivity level, the mid- and far-infrared universe. A Number of deep surveys were performed to probe the cosmological evolution of galaxies. In this review, I discuss and summarize results of mid-infrared ISOCAM and far-infrared ISOPHOT surveys, and show how our vision of the extragalactic infrared universe has become more accurate. In particular, ISO allowed us to resolve into sources a significant fraction of the Cosmic Infrared Background (CIB) in the mid-infrared, and to probe a fainter population in the far-infrared with the detection of the CIB fluctuations. Together with other wavelength data sets, the nature of ISO galaxies is now in the process of being understood. I also show that the high quality of the ISO data put strong constraints on the scenarios of galaxy evolution. This induced a burst in the development of models, yielding to a more coherent picture of galaxy evolution. I finally emphasize the potential of the ISO data archive in the field of observational cosmology, and describe the next steps, in particular the forthcoming cosmological surveys to be carried out by SIRTF.

  17. Modeling Data-Intensive Web Sites 259 ModelingData-Intensive

    E-Print Network [OSTI]

    Bouras, Christos

    Modeling Data-Intensive Web Sites 259 ChapterXII ModelingData-Intensive Web Sites-by-stepapproachtothedesign,implementation and management of a Data-Intensive Web Site (DIWS). The approach introduces five data formulation is that of "Web fragments," that is an information decomposition technique that aids design, implementation

  18. Measurement of the Cosmic Ray Energy Spectrum and Composition from 10^{17} to 10^{18.3} eV Using a Hybrid Fluorescence Technique

    E-Print Network [OSTI]

    T. Abu-Zayyad; K. Belov; D. J. Bird; J. Boyer; Z. Cao; M. Catanese; G. F. Chen; R. W. Clay; C. E. Covault; H. Y. Dai; B. R. Dawson; J. W. Elbert; B. E. Fick; L. F. Fortson; J. W. Fowler; K. G. Gibbs; M. A. K. Glasmacher; K. D. Green; Y. Ho; A. Huang; C. C. Jui; M. J. Kidd; D. B. Kieda; B. C. Knapp; S. Ko; C. G. Larsen; W. Lee; E. C. Loh; E. J. Mannel; J. Matthews; J. N. Matthews; B. J. Newport; D. F. Nitz; R. A. Ong; K. M. Simpson; J. D. Smith; D. Sinclair; P. Sokolsky; P. Sommers; C. Song; J. K. K. Tang; S. B. Thomas; J. .van der Velde; L. R. Wiencke; C. R. Wilkinson; S. Yoshida; X. Z. Zhang

    2000-10-31T23:59:59.000Z

    We study the spectrum and average mass composition of cosmic rays with primary energies between 10^{17} eV and 10^{18} eV using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum as a function of energy. A complete Monte Carlo simulation of the detector response and comparisons with shower simulations leads to the conclusion that the cosmic ray intensity is changing f rom a heavier to a lighter composition in this energy range. The spectrum is consistent with earlier Fly's Eye measurements and supports the previously found steepening near 4 \\times 10^{17} eV .

  19. Frontier of Fusion Research: Path to the Steady State Fusion Reactor by Large Helical Device

    SciTech Connect (OSTI)

    Motojima, Osamu [National Institute for Fusion Science, Toki-shi, Gifu-ken, 509-5292 (Japan)

    2006-12-01T23:59:59.000Z

    The ITER, the International Thermonuclear Experimental Reactor, which will be built in Cadarache in France, has finally started this year, 2006. Since the thermal energy produced by fusion reactions divided by the external heating power, i.e., the Q value, will be larger than 10, this is a big step of the fusion research for half a century trying to tame the nuclear fusion for the 6.5 Billion people on the Earth. The source of the Sun's power is lasting steadily and safely for 8 Billion years. As a potentially safe environmentally friendly and economically competitive energy source, fusion should provide a sustainable future energy supply for all mankind for ten thousands of years. At the frontier of fusion research important milestones are recently marked on a long road toward a true prototype fusion reactor. In its own merits, research into harnessing turbulent burning plasmas and thereby controlling fusion reaction, is one of the grand challenges of complex systems science.After a brief overview of a status of world fusion projects, a focus is given on fusion research at the National Institute for Fusion Science (NIFS) in Japan, which is playing a role of the Inter University Institute, the coordinating Center of Excellence for academic fusion research and by the Large Helical Device (LHD), the world's largest superconducting heliotron device, as a National Users' facility. The current status of LHD project is presented focusing on the experimental program and the recent achievements in basic parameters and in steady state operations. Since, its start in a year 1998, a remarkable progress has presently resulted in the temperature of 140 Million degree, the highest density of 500 Thousand Billion/cc with the internal density barrier (IDB) and the highest steady average beta of 4.5% in helical plasma devices and the largest total input energy of 1.6 GJ, in all magnetic confinement fusion devices. Finally, a perspective is given of the ITER Broad Approach program as an integrated part of ITER and Development of Fusion Energy project Agreement. Moreover, the relationship with the NIFS' new parent organization the National Institutes of Natural Sciences and with foreign research institutions is briefly explained.

  20. Eco-Hydro-Climate Science/Engineering in SESE Definition: An emerging frontier in Earth system science is the interaction of ecological,

    E-Print Network [OSTI]

    Rhoads, James

    Eco-Hydro-Climate Science/Engineering in SESE Definition: An emerging frontier in Earth system that are `retooled' to treat the coupled eco-hydro-climate system. Arid and semiarid regions (deserts) are a fruitful Southwest is thus an ideal laboratory for eco-hydro-climate studies and provides several case studies

  1. [Frontiers in Bioscience 15, 249-258, January 1, 2010] A pharmacodynamic model of Aurora kinase inhibitors in the spindle assembly checkpoint

    E-Print Network [OSTI]

    Davidson, Fordyce A.

    [Frontiers in Bioscience 15, 249-258, January 1, 2010] 249 A pharmacodynamic model of Aurora kinase OF CONTENTS 1. Abstract 2. Introduction 2.1. Aurora kinases and the spindle assembly checkpoint 2.2. Pharmacodynamic modelling 3. Model construction 3.1. Aurora kinase activity and biomarkers 3.2. Kinetochore

  2. Division of Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo Guide to The 2014 Entrance Examination of Master & Doctor Courses and Inquiry Sheet

    E-Print Network [OSTI]

    Yamamoto, Hirosuke

    Division of Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo and Program Master Course Doctor Course Information on Entrance Examination ? 2Division of Environmental. of Natural Environmental Studies 8 22 53Dept. of Ocean Technology, Policy, and Environment 10 24 64Dept

  3. Critical frontier of the Potts and percolation models in triangular-type and kagome-type lattices I: Closed-form expressions

    E-Print Network [OSTI]

    F. Y. Wu

    2009-11-13T23:59:59.000Z

    We consider the Potts model and the related bond, site, and mixed site-bond percolation problems on triangular-type and kagome-type lattices, and derive closed-form expressions for the critical frontier. For triangular-type lattices the critical frontier is known, usually derived from a duality consideration in conjunction with the assumption of a unique transition. Our analysis, however, is rigorous and based on an established result without the need of a uniqueness assumption, thus firmly establishing all derived results. For kagome-type lattices the exact critical frontier is not known. We derive a closed-form expression for the Potts critical frontier by making use of a homogeneity assumption. The closed-form expression is new, and we apply it to a host of problems including site, bond, and mixed site-bond percolation on various lattices. It yields exact thresholds for site percolation on kagome, martini, and other lattices, and is highly accurate numerically in other applications when compared to numerical determination.

  4. Frontiers in Laser Cooling, Single-Molecule Biophysics, and Energy Science: Remarks from Steve Chu at the Scientific Symposium Held in his Honor

    SciTech Connect (OSTI)

    Chu, Steve

    2008-08-30T23:59:59.000Z

    Steve Chu, director of Lawrence Berkeley National Laboratory and recipient of the 1997 Nobel Prize, presents a talk at Frontiers in Laser Cooling, Single-Molecule Biophysics and Energy Science, a scientific symposium in his honor. The symposium was held August 30, 2008 in Berkeley.

  5. Semiconductor lasers with uniform longitudinal intensity distribution

    SciTech Connect (OSTI)

    Schrans, T.; Yariv, A. (Department of Applied Physics 128-95, California Institute of Technology, Pasadena, California 91125 (USA))

    1990-04-16T23:59:59.000Z

    Power-dependent nonuniform longitudinal intensity distribution leading to spectral and spatial instabilities is a major problem in semiconductor lasers. It is shown theoretically that a proper choice of the longitudinal distribution of the gain as well as that of the magnitude of the grating coupling coefficient will lead to a uniform intensity distribution in distributed feedback lasers. We also show that the widely used phase, rather than magnitude, control of the coupling coefficient cannot lead to a uniform intensity distribution when the facet reflectivities are zero.

  6. Feedback Heating by Cosmic Rays in Clusters of Galaxies

    E-Print Network [OSTI]

    Fulai Guo; S. Peng OH

    2007-11-07T23:59:59.000Z

    Recent observations show that the cooling flows in the central regions of galaxy clusters are highly suppressed. Observed AGN-induced cavities/bubbles are a leading candidate for suppressing cooling, usually via some form of mechanical heating. At the same time, observed X-ray cavities and synchrotron emission point toward a significant non-thermal particle population. Previous studies have focused on the dynamical effects of cosmic-ray pressure support, but none have built successful models in which cosmic-ray heating is significant. Here we investigate a new model of AGN heating, in which the intracluster medium is efficiently heated by cosmic-rays, which are injected into the ICM through diffusion or the shredding of the bubbles by Rayleigh-Taylor or Kelvin-Helmholtz instabilities. We include thermal conduction as well. Using numerical simulations, we show that the cooling catastrophe is efficiently suppressed. The cluster quickly relaxes to a quasi-equilibrium state with a highly reduced accretion rate and temperature and density profiles which match observations. Unlike the conduction-only case, no fine-tuning of the Spitzer conduction suppression factor f is needed. The cosmic ray pressure, P_c/P_g heating is a very attractive alternative to mechanical heating, and may become particularly compelling if GLAST detects the gamma-ray signature of cosmic-rays in clusters.

  7. Cosmic and Galactic Neutrino Backgrounds from Thermonuclear Sources

    E-Print Network [OSTI]

    Cristiano Porciani; Silvia Petroni; Giovanni Fiorentini

    2003-11-20T23:59:59.000Z

    We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of the cosmic star formation history and the stellar initial mass function with accurate theoretical predictions of the neutrino yields all over the thermonuclear lifetime of stars of different masses. Models of the structure and evolution of the Milky Way are used to derive maps of the expected flux generated by Galactic sources as a function of sky direction. The predicted neutrino backgrounds depend only slightly on model parameters. In the relevant 50 keV-10 MeV window, the total flux of cosmic neutrinos ranges between 20 and 65 particles per square cm per s. Neutrinos reaching the Earth today have been typically emitted at redshift z~2. Their energy spectrum peaks at E~0.1-0.3 MeV. The energy and entropy densities of the cosmic background are negligible with respect to the thermal contribution of relic neutrinos originated in the early universe. In every sky direction, the cosmic background is outnumbered by the Galactic one, whose integrated flux amounts to 300-1000 particles per square cm per s. The emission from stars in the Galactic disk contributes more than 95 per cent of the signal.

  8. Primordial Helium And the Cosmic Background Radiation

    E-Print Network [OSTI]

    Gary Steigman

    2010-04-29T23:59:59.000Z

    The products of primordial nucleosynthesis and the cosmic microwave background (CMB) photons are relics from the early evolution of the Universe whose observations probe the standard model of cosmology and provide windows on new physics beyond the standard models of cosmology and of particle physics. In the standard, hot big bang cosmology, long before any stars have formed a significant fraction (~25%) of the baryonic mass in the Universe should be in the form of helium-4 nuclei. Since current 4He observations are restricted to low redshift regions where stellar nucleosynthesis has occurred, observations of high redshift, prestellar 4He would constitute a fundamental test of the hot, big bang cosmology. At recombination, long after big bang nucleosynthesis (BBN) has ended, the temperature anisotropy spectrum imprinted on the CMB depends on the 4He abundance through its connection to the electron density and the effect of the electron density on Silk damping. Since the relic abundance of 4He is relatively insensitive to the universal density of baryons, but is sensitive to a non-standard, early Universe expansion rate, the primordial mass fraction of 4He, Yp, offers a test of the consistency of the standard models of BBN and the CMB and, provides constraints on non-standard physics. Here, the WMAP seven year data (supplemented by other CMB experiments), which lead to an indirect determination of Yp at high redshift, are compared to the BBN predictions and to the independent, direct observations of 4He in low redshift, extragalactic HII regions. At present, given the very large uncertainties in the CMB-determined primordial 4He abundance (as well as for the helium abundances inferred from H II region observations), any differences between the BBN predictions and the CMB observations are small, at a level < 1.5 sigma.

  9. Testing cosmology with cosmic sound waves

    SciTech Connect (OSTI)

    Corasaniti, Pier Stefano [LUTH, Observatoire de Paris, CNRS UMR 8102, Universite Paris Diderot, 5 Place Jules Janssen, 92195 Meudon Cedex (France); Melchiorri, Alessandro [Dipartimento di Fisica e Sezione INFN, Universita degli Studi di Roma 'La Sapienza', Ple Aldo Moro 5, 00185, Rome (Italy); CERN, Theory Division, CH-1211 Geneva 23 (Switzerland)

    2008-05-15T23:59:59.000Z

    Wilkinson Microwave Anisotropy Probe (WMAP) observations have accurately determined the position of the first two peaks and dips in the cosmic microwave background (CMB) temperature power spectrum. These encode information on the ratio of the distance to the last scattering surface to the sound horizon at decoupling. However prerecombination processes can contaminate this distance information. In order to assess the amplitude of these effects, we use the WMAP data and evaluate the relative differences of the CMB peak and dip multipoles. We find that the position of the first peak is largely displaced with respect to the expected position of the sound horizon scale at decoupling. In contrast, the relative spacings of the higher extrema are statistically consistent with those expected from perfect harmonic oscillations. This provides evidence for a scale dependent phase shift of the CMB oscillations which is caused by gravitational driving forces affecting the propagation of sound waves before recombination. By accounting for these effects we have performed a Markov Chain Monte Carlo likelihood analysis of the location of WMAP extrema to constrain, in combination with recent BAO data, a constant dark energy equation of state parameter w. For a flat universe we find a strong 2{sigma} upper limit w<-1.10, and including the Hubble Space Telescope prior, we obtain w<-1.14, which is only marginally consistent with limits derived from the Supernova Legacy Survey sample. On the other hand, we infer larger limits for nonflat cosmologies. From the full CMB likelihood analysis, we also estimate the values of the shift parameter R and the multipole l{sub a} of the acoustic horizon at decoupling for several cosmologies, to test their dependence on model assumptions. Although the analysis of the full CMB spectra should always be preferred, using the position of the CMB peaks and dips provides a simple and consistent method for combining CMB constraints with other data sets.

  10. Physics Prospects with an Intense Neutrino Experiment

    E-Print Network [OSTI]

    N. Solomey

    2000-06-16T23:59:59.000Z

    With new forthcoming intense neutrino beams, for the study of neutrino oscillations, it is possible to consider other physics experiments that can be done with these extreme neutrino fluxes available close to the source.

  11. Computational phase imaging based on intensity transport

    E-Print Network [OSTI]

    Waller, Laura A. (Laura Ann)

    2010-01-01T23:59:59.000Z

    Light is a wave, having both an amplitude and a phase. However, optical frequencies are too high to allow direct detection of phase; thus, our eyes and cameras see only real values - intensity. Phase carries important ...

  12. Building dependability arguments for software intensive systems

    E-Print Network [OSTI]

    Seater, Robert Morrison

    2009-01-01T23:59:59.000Z

    A method is introduced for structuring and guiding the development of end-to-end dependability arguments. The goal is to establish high-level requirements of complex software-intensive systems, especially properties that ...

  13. Midlevel ventilation's constraint on tropical cyclone intensity

    E-Print Network [OSTI]

    Tang, Brian Hong-An

    2010-01-01T23:59:59.000Z

    Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a TC's intensity. An idealized ...

  14. Midlevel Ventilation's Constraint on Tropical Cyclone Intensity

    E-Print Network [OSTI]

    Tang, Brian Hong-An

    Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a tropical cyclone’s intensity. An ...

  15. Transport of elliptic intense charged -particle beams

    E-Print Network [OSTI]

    Zhou, J. (Jing), 1978-

    2006-01-01T23:59:59.000Z

    The transport theory of high-intensity elliptic charged-particle beams is presented. In particular, the halo formation and beam loss problem associated with the high space charge and small-aperture structure is addressed, ...

  16. Absolute vs. intensity-based emission caps

    E-Print Network [OSTI]

    Ellerman, A. Denny.

    Cap-and-trade systems limit emissions to some pre-specified absolute quantity. Intensity-based limits, that restrict emissions to some pre-specified rate relative to input or output, are much more widely used in environmental ...

  17. Laser intensity effects in noncommutative QED

    E-Print Network [OSTI]

    Thomas Heinzl; Anton Ilderton; Mattias Marklund

    2010-02-17T23:59:59.000Z

    We discuss a two-fold extension of QED assuming the presence of strong external fields provided by an ultra-intense laser and noncommutativity of spacetime. While noncommutative effects leave the electron's intensity induced mass shift unchanged, the photons change significantly in character: they acquire a quasi-momentum that is no longer light-like. We study the consequences of this combined noncommutative strong-field effect for basic lepton-photon interactions.

  18. ISOTOPIC COMPOSITION OF LIGHT NUCLEI IN COSMIC RAYS: RESULTS FROM AMS-01

    E-Print Network [OSTI]

    Becker, R.

    The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper, we ...

  19. Distributed Storage Systems for Data Intensive Computing

    SciTech Connect (OSTI)

    Vazhkudai, Sudharshan S [ORNL; Butt, Ali R [Virginia Polytechnic Institute and State University (Virginia Tech); Ma, Xiaosong [ORNL

    2012-01-01T23:59:59.000Z

    In this chapter, the authors present an overview of the utility of distributed storage systems in supporting modern applications that are increasingly becoming data intensive. Their coverage of distributed storage systems is based on the requirements imposed by data intensive computing and not a mere summary of storage systems. To this end, they delve into several aspects of supporting data-intensive analysis, such as data staging, offloading, checkpointing, and end-user access to terabytes of data, and illustrate the use of novel techniques and methodologies for realizing distributed storage systems therein. The data deluge from scientific experiments, observations, and simulations is affecting all of the aforementioned day-to-day operations in data-intensive computing. Modern distributed storage systems employ techniques that can help improve application performance, alleviate I/O bandwidth bottleneck, mask failures, and improve data availability. They present key guiding principles involved in the construction of such storage systems, associated tradeoffs, design, and architecture, all with an eye toward addressing challenges of data-intensive scientific applications. They highlight the concepts involved using several case studies of state-of-the-art storage systems that are currently available in the data-intensive computing landscape.

  20. Radio detection of cosmic ray air showers with LOPES

    E-Print Network [OSTI]

    Huege, T; Asch, T; Badea, A F; Bähren, L; Bekk, K; Bercuci, A; Bertaina, M; Biermann, P L; Blumer, J; Bozdog, H; Brancus, I M; Buitink, S; Bruggemann, M; Buchholz, P; Butcher, H; Chiavassa, A; Cossavella, F; Daumiller, K; Di Pierro, F; Doll, P; Engel, R; Falcke, H; Gemmeke, H; Ghia, P L; Glasstetter, R; Grupen, C; Hakenjos, A; Haungs, A; Heck, D; Hörandel, J R; Horneffer, A; Isar, P G; Kampert, K H; Kolotaev, Yu; Krömer, O; Kuijpers, J; Lafebre, S; Mathes, H J; Mayer, H J; Meurer, C; Milke, J; Mitrica, B; Morello, C; Navarra, G; Nehls, S; Nigl, A; Obenland, R; Oehlschläger, J; Ostapchenko, S; Over, S; Petcu, M; Petrovic, J; Pierog, T; Plewnia, S; Rebel, H; Risse, A; Roth, M; Schieler, H; Sima, O; Singh, K; Stumpert, M; Toma, G; Trinchero, G C; Ulrich, H; Van Buren, J; Walkowiak, W; Weindl, A; Wochele, J; Zabierowski, J; Zensus, J A; Zimmermann, D; Huege, Tim; al, et

    2006-01-01T23:59:59.000Z

    In the last few years, radio detection of cosmic ray air showers has experienced a true renaissance, becoming manifest in a number of new experiments and simulation efforts. In particular, the LOPES project has successfully implemented modern interferometric methods to measure the radio emission from extensive air showers. LOPES has confirmed that the emission is coherent and of geomagnetic origin, as expected by the geosynchrotron mechanism, and has demonstrated that a large scale application of the radio technique has great potential to complement current measurements of ultra-high energy cosmic rays. We describe the current status, most recent results and open questions regarding radio detection of cosmic rays and give an overview of ongoing research and development for an application of the radio technique in the framework of the Pierre Auger Observatory.

  1. Radio detection of cosmic ray air showers with LOPES

    E-Print Network [OSTI]

    Tim Huege; the LOPES Collaboration

    2006-09-15T23:59:59.000Z

    In the last few years, radio detection of cosmic ray air showers has experienced a true renaissance, becoming manifest in a number of new experiments and simulation efforts. In particular, the LOPES project has successfully implemented modern interferometric methods to measure the radio emission from extensive air showers. LOPES has confirmed that the emission is coherent and of geomagnetic origin, as expected by the geosynchrotron mechanism, and has demonstrated that a large scale application of the radio technique has great potential to complement current measurements of ultra-high energy cosmic rays. We describe the current status, most recent results and open questions regarding radio detection of cosmic rays and give an overview of ongoing research and development for an application of the radio technique in the framework of the Pierre Auger Observatory.

  2. Growth of Cosmic Structure: Probing Dark Energy Beyond Expansion

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Huterer, Dragan; Kirkby, David; Bean, Rachel; Connolly, Andrew; Dawson, Kyle; Dodelson, Scott; Evrard, August; Jain, Bhuvnesh; Jarvis, Michael; Linder, Eric; et al

    2015-03-01T23:59:59.000Z

    The quantity and quality of cosmic structure observations have greatly accelerated in recent years, and further leaps forward will be facilitated by imminent projects. These will enable us to map the evolution of dark and baryonic matter density fluctuations over cosmic history. The way that these fluctuations vary over space and time is sensitive to several pieces of fundamental physics: the primordial perturbations generated by GUT-scale physics; neutrino masses and interactions; the nature of dark matter and dark energy. We focus on the last of these here: the ways that combining probes of growth with those of the cosmic expansionmore »such as distance-redshift relations will pin down the mechanism driving the acceleration of the Universe.« less

  3. Plasma Wakefield Acceleration for Ultrahigh Energy Cosmic Rays

    E-Print Network [OSTI]

    Pisin Chen; Toshiki Tajima; Yoshiyuki Takahashi

    2002-05-21T23:59:59.000Z

    A cosmic acceleration mechanism is introduced which is based on the wakefields excited by the Alfven shocks in a relativistically flowing plasma, where the energy gain per distance of a test particle is Lorentz invariant. We show that there exists a threshold condition for transparency below which the accelerating particle is collision-free and suffers little energy loss in the plasma medium. The stochastic encounters of the random accelerating-decelerating phases results in a power-law energy spectrum: f(e) 1/e^2. The environment suitable for such plasma wakefield acceleration can be cosmically abundant. As an example, we discuss the possible production of super-GZK ultra high energy cosmic rays (UHECR) through this mechanism in the atmosphere of gamma ray bursts. We show that the acceleration gradient can be as high as G ~ 10^16 eV/cm. The estimated event rate in our model agrees with that from UHECR observations.

  4. Growth of Cosmic Structure: Probing Dark Energy Beyond Expansion

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Huterer, Dragan [University of Michigan, Department of Physics Ann Harbor, MI (United States); Kirkby, David [UC Irvine, Department of Physics and Astronomy, CA (United States); Bean, Rachel [Cornell University, Department of Astronomy, Ithaca, NY (United States); Connolly, Andrew [University of Washington, Department of Astronomy, Seattle, WA (United States); Dawson, Kyle [University of Utah, Department of Physics & Astronomy, Salt Lake City, UT (United States); Dodelson, Scott [Fermi National Accelerator Laboratory, Fermilab Center for Particle Astrophysics, Batavia, IL (United States); University of Chicago, Department of Physics & Astrophysics, Chicago, IL (United States); Evrard, August [University of Michigan, Department of Physics Ann Harbor, MI (United States); Jain, Bhuvnesh [University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, PA (United States); Jarvis, Michael [University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, PA (United States); Linder, Eric [Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Mandelbaum, Rachel [Carnegie Mellon University, Department of Physics, Pittsburgh, PA (United States); May, Morgan [Brookhaven National Laboratory (BNL), Upton, NY (United States); Raccanelli, Alvise [California Institute of Technology, NASA Jet Propulsion Laboratory, Pasadena, CA (United States); Reid, Beth [Lawrence Berkeley National Laboratory, Physics Division, Berkeley, CA (United States); Rozo, Eduardo [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Schmidt, Fabian [Princeton University, Department of Astrophysical Sciences, Princeton, NJ (United States); Max-Planck-Insitute for Astrophysics, Garching (Germany); Sehgal, Neelima [Stony Brook University, NY (United States); Slosar, Anze [Brookhaven National Laboratory (BNL), Upton, NY (United States); Van Engelen, Alex [Stony Brook University, NY (United States); Wu, Hao-Yi [University of Michigan, Department of Physics, Ann Harbor, MI (United States); Zhao, Gongbo [Chinese Academy of Science, National Astronomy Observatories, Beijing (China)

    2015-03-01T23:59:59.000Z

    The quantity and quality of cosmic structure observations have greatly accelerated in recent years, and further leaps forward will be facilitated by imminent projects. These will enable us to map the evolution of dark and baryonic matter density fluctuations over cosmic history. The way that these fluctuations vary over space and time is sensitive to several pieces of fundamental physics: the primordial perturbations generated by GUT-scale physics; neutrino masses and interactions; the nature of dark matter and dark energy. We focus on the last of these here: the ways that combining probes of growth with those of the cosmic expansion such as distance-redshift relations will pin down the mechanism driving the acceleration of the Universe.

  5. Cosmic Rays from the Knee to the Ankle

    E-Print Network [OSTI]

    Haungs, Andreas

    2015-01-01T23:59:59.000Z

    Investigations of the energy spectrum as well as the mass composition of cosmic rays in the energy range of PeVto EeV are important for understanding both, the origin of the galactic and the extragalactic cosmic rays. Recently, three modern experimental installations (KASCADE-Grande, IceTop, Tunka-133), dedicated to investigate this primary energy range, have published new results on the all-particle energy spectrum. In this short review these results are presented and the similarities and differences discussed. In addition, the effects of using different hadronic interaction models for interpreting the measured air-shower data will be examined. Finally, a brief discussion on the question if the present results are in agreement or in contradiction with astrophysical models for the transition from galactic to 10 pagesextragalactic origin of cosmic rays completes this paper.

  6. Production of Neutrinos and Secondary Electrons in Cosmic Sources

    E-Print Network [OSTI]

    C. -Y. Huang; M. Pohl

    2008-01-23T23:59:59.000Z

    We study the individual contribution to secondary lepton production in hadronic interactions of cosmic rays (CRs) including resonances and heavier secondaries. For this purpose we use the same ethodology discussed earlier \\cite{Huang07}, namely the Monte Carlo particle collision code DPMJET3.04 to determine the multiplicity spectra of various secondary particles with leptons as the final decay states, that result from inelastic collisions of cosmic-ray protons and Helium nuclei with the interstellar medium of standard composition. By combining the simulation results with parametric models for secondary particle (with resonances included) for incident cosmic-ray energies below a few GeV, where DPMJET appears unreliable, we thus derive production matrices for all stable secondary particles in cosmic-ray interactions with energies up to about 10 PeV. We apply the production matrices to calculate the radio synchrotron radiation of secondary electrons in a young shell-type SNR, RX J1713.7-3946, which is a measure of the age, the spectral index of hadronic cosmic rays, and most importantly the magnetic field strength. We find that the multi-mG fields recently invoked to explain the X-ray flux variations are unlikely to extend over a large fraction of the radio-emitting region, otherwise the spectrum of hadronic cosmic rays in the energy window 0.1-100 GeV must be unusually hard. We also use the production matrices to calculate the muon event rate in an IceCube-like detector that are induced by muon neutrinos from high-energy $\\gamma$-ray sources such as RX J1713.7-3946, Vela Jr. and MGRO J2019+37. At muon energies of a few TeV, or in other word, about 10 TeV neutrino energy, an accumulation of data over about five to ten years would allow testing the hadronic origin of TeV $\\gamma$-rays.

  7. Neutrino, Neutron, and Cosmic Ray Production in the External Shock Model of Gamma Ray Bursts

    E-Print Network [OSTI]

    Charles D. Dermer

    2002-04-16T23:59:59.000Z

    The hypothesis that ultra-high energy (>~ 10^19 eV) cosmic rays (UHECRs) are accelerated by gamma-ray burst (GRB) blast waves is assumed to be correct. Implications of this assumption are then derived for the external shock model of gamma-ray bursts. The evolving synchrotron radiation spectrum in GRB blast waves provides target photons for the photomeson production of neutrinos and neutrons. Decay characteristics and radiative efficiencies of the neutral particles that escape from the blast wave are calculated. The diffuse high-energy GRB neutrino background and the distribution of high-energy GRB neutrino events are calculated for specific parameter sets, and a scaling relation for the photomeson production efficiency in surroundings with different densities is derived. GRBs provide an intense flux of high-energy neutrons, with neutron-production efficiencies exceeding ~ 1% of the total energy release. The radiative characteristics of the neutron beta-decay electrons from the GRB "neutron bomb" are solved in a special case. Galaxies with GRB activity should be surrounded by radiation halos of ~ 100 kpc extent from the outflowing neutrons, consisting of a nonthermal optical/X-ray synchrotron component and a high-energy gamma-ray component from Compton-scattered microwave background radiation. The luminosity of sources of GRBs and relativistic outflows in L* galaxies such as the Milky Way is at the level of ~10^40+-1 ergs/s. This is sufficient to account for UHECR generation by GRBs. We briefly speculate on the possibility that hadronic cosmic rays originate from the subset of supernovae that collapse to form relativistic outflows and GRBs. (abridged)

  8. Gamma-Ray Bursts, Ultra High Energy Cosmic Rays, and Cosmic Gamma-Ray Background

    E-Print Network [OSTI]

    Tomonori Totani

    1999-04-13T23:59:59.000Z

    We argue that gamma-ray bursts (GRBs) may be the origin of the cosmic gamma-ray background radiation observed in GeV range. It has theoretically been discussed that protons may carry a much larger amount of energy than electrons in GRBs, and this large energy can be radiated in TeV range by synchrotron radiation of ultra-high-energy protons (\\sim 10^{20} eV). The possible detection of GRBs above 10 TeV suggested by the Tibet and HEGRA groups also supports this idea. If this is the case, most of TeV gamma-rays from GRBs are absorbed in intergalactic fields and eventually form GeV gamma-ray background, whose flux is in good agreement with the recent observation.

  9. CMS Data Processing Workflows during an Extended Cosmic Ray Run

    SciTech Connect (OSTI)

    Not Available

    2009-11-01T23:59:59.000Z

    The CMS Collaboration conducted a month-long data taking exercise, the Cosmic Run At Four Tesla, during October-November 2008, with the goal of commissioning the experiment for extended operation. With all installed detector systems participating, CMS recorded 270 million cosmic ray events with the solenoid at a magnetic field strength of 3.8 T. This paper describes the data flow from the detector through the various online and offline computing systems, as well as the workflows used for recording the data, for aligning and calibrating the detector, and for analysis of the data.

  10. Method for detecting moisture in soils using secondary cosmic radiation

    DOE Patents [OSTI]

    Condreva, Kenneth

    2003-12-16T23:59:59.000Z

    Water content in a soil is determined by measuring the attenuation of secondary background cosmic radiation as this radiation propagates through a layer of soil and water. By measuring the attenuation of secondary cosmic radiation in the range of 5 MeV-15 MeV it is possible to obtain a relative measure of the water content in a soil layer above a suitable radiation detector and thus establish when and how much irrigation is needed. The electronic circuitry is designed so that a battery pack can be used to supply power.

  11. Black Hole Collisions, Analytic Continuation, and Cosmic Censorship

    E-Print Network [OSTI]

    Dieter R. Brill

    1995-03-27T23:59:59.000Z

    Exact solutions of the Einstein-Maxwell equations that describe moving black holes in a cosmological setting are discussed with the aim of discovering the global structure and testing cosmic censorship. Continuation beyond the horizons present in these solutions is necessary in order to identify the global structure. Therefore the possibilities and methods of analytic extension of geometries are briefly reviewed. The global structure of the Reissner-Nordstr\\"om-de Sitter geometry is found by these methods. When several black holes are present, the exact solution is no longer everywhere analytic, but less smooth extensions satisfying the Einstein equations everywhere are possible. Some of these provide counterexamples to cosmic censorship.

  12. Energy spectrum of ultra high energy cosmic rays

    E-Print Network [OSTI]

    Ioana C. Maris; for the Pierre Auger Collaboration

    2008-08-12T23:59:59.000Z

    The construction of the southern site of the Pierre Auger Observatory is almost completed. Three independent measurements of the flux of the cosmic rays with energies larger than 1 EeV have been performed during the construction phase. The surface detector data collected until August 2007 have been used to establish a flux suppression at the highest energies with a 6 sigma significance. The observations of cosmic rays by the fluorescence detector allowed the extension of the energy spectrum to lower energies, where the efficiency of the surface detector is less than 100% and a change in the spectral index is expected.

  13. Note on Structure Formation from Cosmic String Wakes

    E-Print Network [OSTI]

    Duplessis, Francis

    2013-01-01T23:59:59.000Z

    The search for cosmic strings has been of renewed interest with the advent of precision cosmology. In this note we give a quantitative description of the nonlinear matter density fluctuations that can form from a scaling network of cosmic string wakes. Specifically, we compute the distribution of dark matter halos. These halos would possess strong correlations in position space that should have survived until today. We also discuss the challenges involved in their detection due to their small size and the complex dynamics of their formation.

  14. Real-Time Active Cosmic Neutron Background Reduction Methods

    SciTech Connect (OSTI)

    Mukhopadhyay, Sanjoy; Maurer, Richard; Wolff, Ronald; Mitchell, Stephen; Guss, Paul

    2013-09-01T23:59:59.000Z

    Neutron counting using large arrays of pressurized 3He proportional counters from an aerial system or in a maritime environment suffers from the background counts from the primary cosmic neutrons and secondary neutrons caused by cosmic ray?induced mechanisms like spallation and charge-exchange reaction. This paper reports the work performed at the Remote Sensing Laboratory–Andrews (RSL-A) and results obtained when using two different methods to reduce the cosmic neutron background in real time. Both methods used shielding materials with a high concentration (up to 30% by weight) of neutron-absorbing materials, such as natural boron, to remove the low-energy neutron flux from the cosmic background as the first step of the background reduction process. Our first method was to design, prototype, and test an up-looking plastic scintillator (BC-400, manufactured by Saint Gobain Corporation) to tag the cosmic neutrons and then create a logic pulse of a fixed time duration (~120 ?s) to block the data taken by the neutron counter (pressurized 3He tubes running in a proportional counter mode). The second method examined the time correlation between the arrival of two successive neutron signals to the counting array and calculated the excess of variance (Feynman variance Y2F)1 in the neutron count distribution from Poisson distribution. The dilution of this variance from cosmic background values ideally would signal the presence of man-made neutrons.2 The first method has been technically successful in tagging the neutrons in the cosmic-ray flux and preventing them from being counted in the 3He tube array by electronic veto—field measurement work shows the efficiency of the electronic veto counter to be about 87%. The second method has successfully derived an empirical relationship between the percentile non-cosmic component in a neutron flux and the Y2F of the measured neutron count distribution. By using shielding materials alone, approximately 55% of the neutron flux from man-made sources like 252Cf or Am-Be was removed.

  15. Inhomogeneus Inflation and Cosmic no-Hair Conjecture

    E-Print Network [OSTI]

    M. A. S. Nobre; M. R. de Garcia Maia; J. C. Carvalho; J. A. S. Lima

    2009-03-20T23:59:59.000Z

    The cosmic no hair conjecture is tested for a large class of inhomogeneous cosmologies with a positive cosmological constant. Firstly, we derive a new class of exact inhomogeneous cosmological solutions whose matter content of the models is formed by a mixture of two interacting simple fluids plus a cosmological Lambda-term. These models generalize the de Sitter spacetime and the inhomogeneous two-fluid Szekeres-type cosmologies derived by Lima and Tiomno. Finally, we show that the late time behaviour of our solutions is in agreement with the "cosmic no hair theorem" of Hawking and Moss.

  16. The Antarctic climate anomaly and galactic cosmic rays

    E-Print Network [OSTI]

    Svensmark, H

    2006-01-01T23:59:59.000Z

    It has been proposed that galactic cosmic rays may influence the Earth's climate by affecting cloud formation. If changes in cloudiness play a part in climate change, their effect changes sign in Antarctica. Satellite data from the Earth Radiation Budget Experiment (ERBE) are here used to calculate the changes in surface temperatures at all latitudes, due to small percentage changes in cloudiness. The results match the observed contrasts in temperature changes, globally and in Antarctica. Evidently clouds do not just respond passively to climate changes but take an active part in the forcing, in accordance with changes in the solar magnetic field that vary the cosmic-ray flux.

  17. 9,400 years of cosmic radiation and solar activity from ice cores and tree rings

    E-Print Network [OSTI]

    Wehrli, Bernhard

    9,400 years of cosmic radiation and solar activity from ice cores and tree rings Friedhelm) Understanding the temporal variation of cosmic radiation and solar activity during the Holocene is essential the history of cosmic radiation and solar activity over many millennia. Although records from different

  18. CMB distortions from damping of acoustic waves produced by cosmic strings

    SciTech Connect (OSTI)

    Tashiro, Hiroyuki; Sabancilar, Eray; Vachaspati, Tanmay, E-mail: Hiroyuki.Tashiro@asu.edu, E-mail: Eray.Sabancilar@asu.edu, E-mail: tvachasp@asu.edu [Physics Department, Arizona State University, Tempe, Arizona 85287 (United States)

    2013-08-01T23:59:59.000Z

    We study diffusion damping of acoustic waves in the photon-baryon fluid due to cosmic strings, and calculate the induced ?- and y-type spectral distortions of the cosmic microwave background. For cosmic strings with tension within current bounds, their contribution to the spectral distortions is subdominant compared to the distortions from primordial density perturbations.

  19. In situ formation of cosmogenic 14 C by cosmic ray nucleons in polar ice

    E-Print Network [OSTI]

    In situ formation of cosmogenic 14 C by cosmic ray nucleons in polar ice Aleksandr Nesterenok 2011 Available online 8 October 2011 Keywords: Cosmic rays Polar ice Radiocarbon In situ production a b s t r a c t We study interactions of cosmic ray particles with the Earth's atmosphere and polar ice

  20. What is Data-Intensive Science?

    SciTech Connect (OSTI)

    Critchlow, Terence J.; Kleese van Dam, Kerstin

    2013-06-03T23:59:59.000Z

    What is Data Intensive Science? Today we are living in a digital world, where scientists often no longer interact directly with the physical object of their research, but do so via digitally captured, reduced, calibrated, analyzed, synthesized and, at times, visualized data. Advances in experimental and computational technologies have lead to an exponential growth in the volumes, variety and complexity of this data and while the deluge is not happening everywhere in an absolute sense, it is in a relative one. Science today is data intensive. Data intensive science has the potential to transform not only how we do science, but how quickly we can translate scientific progress into complete solutions, policies, decisions and ultimately economic success. Critically, data intensive science touches some of the most important challenges we are facing. Consider a few of the grand challenges outlined by the U.S. National Academy of Engineering: make solar energy economical, provide energy from fusion, develop carbon sequestration methods, advance health informatics, engineer better medicines, secure cyberspace, and engineer the tools of scientific discovery. Arguably, meeting any of these challenges requires the collaborative effort of trans-disciplinary teams, but also significant contributions from enabling data intensive technologies. Indeed for many of them, advances in data intensive research will be the single most important factor in developing successful and timely solutions. Simple extrapolations of how we currently interact with and utilize data and knowledge are not sufficient to meet this need. Given the importance of these challenges, a new, bold vision for the role of data in science, and indeed how research will be conducted in a data intensive environment is evolving.

  1. On the Interaction Between Cosmic Rays and Dark Matter Molecular Clouds - II. The Age Distribution of Cosmic Ray Electrons

    E-Print Network [OSTI]

    D. W. Sciama

    1999-09-14T23:59:59.000Z

    We explore further the proposal in paper I of this series that the confinement time of cosmic ray nuclei in the Milky Way is determined by their interaction with dark matter molecular clouds rather than by their escape from the halo, as is assumed in conventional models of cosmic ray propagation. The same proposal can be made for cosmic ray electrons. This proposal leads to a specific age distribution for the electrons which is in agreement with Tang's (1984) observations of the electron spectrum at high energies but not with Nishimura et al's (1980) earlier data, which lead to a flatter spectrum. However, the simplest leaky box and diffusion models disagree with both sets of data so that our trapping model is supported if Tang's data are correct.

  2. Heavy Quark and Neutrino Physics Final Report 2011 – 2014

    SciTech Connect (OSTI)

    Horton-Smith, Glenn A. [Kansas State University] (ORCID:0000000196779167); Bolton, Timothy [Kansas State University; Ivanov, Andrew [Kansas State University; Maravin, Yurii [Kansas State University; Ratra, Bharat [Kansas State University

    2014-07-21T23:59:59.000Z

    This final closeout report covers research supported by the ``Heavy Quark and Neutrino Physics'' grant at Kansas State University during the grant's last renewal period, November 1, 2011, through April 30, 2014. The report begins with an overview of the group, its goals and activities, and personnel. Then summaries are given of achievements in each of the three frontiers: Energy Frontier research in the D0 and CMS experiments; Intensity Frontier research in the Double Chooz and ArgoNeuT experiments as well as research and development for MicroBooNE and LBNE; and Cosmic Frontier and Theoretical research. The report concludes with a list of publications supported by this grant in which our group made a significant contribution during the reporting period, followed by a list of students partially or fully supported by the grant who were awarded a PhD during this period.

  3. Upper Cretaceous Ferron-Frontier clastic wedge, Utah and Wyoming - interplay between sea level, sediment supply, and subsidence

    SciTech Connect (OSTI)

    Ryer, T.A.

    1986-08-01T23:59:59.000Z

    The Ferron-Frontier clastic wedge is among the most widespread in the Cretaceous System of North America. Some writers have emphasized the role of eustatic sea level in forming this clastic wedge; others have emphasized tectonics and variations in sediment supply. The evidence indicates that both were important, but to varying degrees and at different times. The Greenhorn regression was rapid, spanning only the middle part of Turonian time. It was caused primarily by lowering of sea level. Vast tracts of the sea floor that had previously been below wave base shoaled and became areas of accumulation of sandy and/or bioclastic-rich sediments. Sea level began to rise during late Turonian time. Subwave-base conditions returned to much of the sea floor, and the shoreline transgressed westward. It was during the Niobrara trangression that uplift in the Sevier orogenic belt and within the western part of the foreland basin caused a large volume of sediment to be carried eastward through the Ferron-Frontier river systems. In southwestern Wyoming, the influx of sediment slowed the transgression and resulted in stacking of shoreline sandstone units. The influx of sediment in central Utah was even greater - so much so that the shoreline once again prograded seaward. Late Turonian time marked the peak regression of the shoreline in that area. The tectonically induced influx of sediment appears to have been short-lived. A continued rise of sea level, combined with renewed downwarping of the foreland basin and trapping of sediment within it, led to abrupt westward transgression of the shoreline during Coniacian time.

  4. absolute intensity calibration: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    good. This is used in a technique developed for the absolute calibration of ultra high energy cosmic ray fluorescence telescopes, and it can also be applied to imaging atmospheric...

  5. Intensity Limitations in Fermilab Main Injector

    SciTech Connect (OSTI)

    Chan, W.

    1997-06-01T23:59:59.000Z

    The design beam intensity of the FNAL Main Injector (MI) is 3 x 10{sup 13} ppp. This paper investigates possible limitations in the intensity upgrade. These include the space charge, transition crossing, microwave instability, coupled bunch instability, resistive wall, beam loading (static and transient), rf power, aperture (physical and dynamic), coalescing, particle losses and radiation shielding, etc. It seems that to increase the intensity by a factor of two from the design value is straightforward. Even a factor of five is possible provided that the following measures are to be taken: an rf power upgrade, a {gamma}{sub t}-jump system, longitudinal and transverse feedback systems, rf feedback and feedforward, stopband corrections and local shieldings.

  6. Masking line foregrounds in intensity mapping surveys

    E-Print Network [OSTI]

    Breysse, Patrick C; Kamionkowski, Marc

    2015-01-01T23:59:59.000Z

    We address the problem of line confusion in intensity mapping surveys and explore the possibility to mitigate line foreground contamination by progressively masking the brightest pixels in the observed map. We consider experiments targeting CO(1-0) at $z=3$, Ly$\\alpha$ at $z=7$, and CII at $z=7$, and use simulated intensity maps, which include both clustering and shot noise components of the signal and possible foregrounds, in order to test the efficiency of our method. We find that for CO and Ly$\\alpha$ it is quite possible to remove most of the foreground contribution from the maps via only 1%-3% pixel masking. The CII maps will be more difficult to clean, however, due to instrumental constraints and the high-intensity foreground contamination involved. While the masking procedure sacrifices much of the astrophysical information present in our maps, we demonstrate that useful cosmological information in the targeted lines can be successfully retrieved.

  7. Radiation Reaction in High-Intense Fields

    E-Print Network [OSTI]

    Seto, Keita

    2015-01-01T23:59:59.000Z

    After the development of the radiating electron model by P. A. M. Dirac in 1938, many authors have tried to reformulate this model so-called radiation reaction. Recently, this effects has become important for ultra-intense laser-electron (plasma) interactions. In our recent research, we found a method for the stabilization of radiation reaction in quantum vacuum [PTEP 2014, 043A01 (2014), PTEP 2015, 023A01 (2015)]. In the other hand, the field modification by high-intense fields should be required under 10PW lasers, like ELI-NP facility. In this paper, I propose the combined method how to adopt the high-intense field correction with the stabilization by quantum vacuum as the extension from the model by Dirac.

  8. The Chelyabinsk Meteor: A Cosmic Wake-up Call?

    E-Print Network [OSTI]

    Robeson, Scott M.

    The Chelyabinsk Meteor: A Cosmic Wake-up Call? Monday, Oct. 14, 8:00 PM Rawles Hall The Inaugural F, the shock wave reached the ground in Chelyabinsk Russia, breaking windows and injuring about 1500 people from flying glass. The Chelyabinsk impactor was smaller

  9. Cosmological Cosmic Rays: Sharpening the Primordial Lithium Problem

    E-Print Network [OSTI]

    Prodanovic, Tijana

    2007-01-01T23:59:59.000Z

    Cosmic structure formation leads to large-scale shocked baryonic flows which are expected to produce a cosmological population of structure-formation cosmic rays (SFCRs). Interactions between SFCRs and ambient baryons will produce lithium isotopes via \\alpha+\\alpha \\to ^{6,7}Li. This pre-Galactic (but non-primordial) lithium should contribute to the primordial 7Li measured in halo stars and must be subtracted in order to arrive to the true observed primordial lithium abundance. In this paper we point out that the recent halo star 6Li measurements can be used to place a strong constraint to the level of such contamination, because the exclusive astrophysical production of 6Li is from cosmic-ray interactions. We find that the putative 6Li plateau, if due to pre-Galactic cosmic-ray interactions, implies that SFCR-produced lithium represents Li_{SFCR}/Li_{plateau}\\approx 15% of the observed elemental Li plateau. Taking the remaining plateau Li to be cosmological 7Li, we find a revised (and slightly worsened) disc...

  10. Cosmic Supernova Rate History and Type Ia Supernova Progenitors

    E-Print Network [OSTI]

    Chiaki Kobayashi; Ken'ichi Nomoto; Takuji Tsujimoto

    2001-02-14T23:59:59.000Z

    Adopting a single degenerate scenario for Type Ia supernova progenitors with the metallicity effect, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in spiral and elliptical galaxies, and compare with the recent observational data up to z ~ 0.55.

  11. The Cosmic Origins Spectrograph: A Hubble Replacement Instrument

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    The Cosmic Origins Spectrograph: A Hubble Replacement Instrument for the 2002 Reservicing Mission Origins Spectrograph (COS) has recently been selected as a replacement instrument for the Hubble Space Telescope. Installation is scheduled for late 2002, replacing COSTAR, which at that time will be unnecessary

  12. Cosmic Web and Environmental Dependence of Screening: Vainshtein vs. Chameleon

    E-Print Network [OSTI]

    Bridget Falck; Kazuya Koyama; Gong-bo Zhao

    2015-03-23T23:59:59.000Z

    Theories which modify general relativity to explain the accelerated expansion of the Universe often use screening mechanisms to satisfy constraints on Solar System scales. We investigate the effects of the cosmic web and the local environmental density of dark matter halos on the screening properties of the Vainshtein and chameleon screening mechanisms. We compare the cosmic web morphology of dark matter particles, mass functions of dark matter halos, mass and radial dependence of screening, velocity dispersions and peculiar velocities, and environmental dependence of screening mechanisms in $f(R)$ and nDGP models. Using the ORIGAMI cosmic web identification routine we find that the Vainshtein mechanism depends on the cosmic web morphology of dark matter particles, since these are defined according to the dimensionality of their collapse, while the chameleon mechanism shows no morphology dependence. The chameleon screening of halos and their velocity dispersions depend on halo mass, and small halos and subhalos can be environmentally screened in the chameleon mechanism. On the other hand, the screening of halos in the Vainshtein mechanism does not depend on mass nor environment, and their velocity dispersions are suppressed. The peculiar velocities of halos in the Vainshtein mechanism are enhanced because screened objects can still feel the fifth force generated by external fields, while peculiar velocities of chameleon halos are suppressed when the halo centers are screened.

  13. Simulations of cosmic ray interactions: past, present, and future

    E-Print Network [OSTI]

    Simulations of cosmic ray interactions: past, present, and future S S Ostapchenko Forschungszentrum data, over many energy decades. #12;2 In past, it was customary to treat hadronic cascades" partonic processes whose role greatly increases with energy. Different ways to account for non- linear

  14. Brane cosmic string compactification in Brans-Dicke theory

    SciTech Connect (OSTI)

    Abdalla, M. C. B.; Hoff da Silva, J. M. [Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145 01405-900 Sao Paulo, SP (Brazil); Guimaraes, M. E. X. [Departamento de Matematica, Universidade de Brasilia, Asa Norte 70910-900, Brasilia-DF (Brazil)

    2007-04-15T23:59:59.000Z

    We investigate an alternative compactification of extra dimensions using local cosmic string in the Brans-Dicke gravity framework. In the context of dynamical systems it is possible to show that there exist a stable field configuration for the Einstein-Brans-Dicke equations. We explore the analogies between this particular model and the Randall-Sundrum scenario.

  15. Reference Radiation for Cosmic Rays in RBE Research

    E-Print Network [OSTI]

    Feng, Shaoyong

    2011-10-21T23:59:59.000Z

    effectiveness relative to a specific radiation is usually used. For low energy heavy ions and neutrons 250 keV photons are usually used for the reference radiation but their depth dose distribution is very different from that for cosmic rays. In this research...

  16. Monte Carlo Simulations of Cosmic Rays Hadronic Interactions

    SciTech Connect (OSTI)

    Aguayo Navarrete, Estanislao; Orrell, John L.; Kouzes, Richard T.

    2011-04-01T23:59:59.000Z

    This document describes the construction and results of the MaCoR software tool, developed to model the hadronic interactions of cosmic rays with different geometries of materials. The ubiquity of cosmic radiation in the environment results in the activation of stable isotopes, referred to as cosmogenic activities. The objective is to use this application in conjunction with a model of the MAJORANA DEMONSTRATOR components, from extraction to deployment, to evaluate cosmogenic activation of such components before and after deployment. The cosmic ray showers include several types of particles with a wide range of energy (MeV to GeV). It is infeasible to compute an exact result with a deterministic algorithm for this problem; Monte Carlo simulations are a more suitable approach to model cosmic ray hadronic interactions. In order to validate the results generated by the application, a test comparing experimental muon flux measurements and those predicted by the application is presented. The experimental and simulated results have a deviation of 3%.

  17. Generalised scalar-tensor theory and the cosmic acceleration

    E-Print Network [OSTI]

    Narayan Banerjee; Koyel Ganguly

    2008-07-11T23:59:59.000Z

    In this paper it has been shown that a simple functional form of $\\omega(\\phi)$ in a generalised scalar tensor theory can drive the present cosmic acceleration without any quintessence field or the cosmological constant $\\Lambda$. Furthermore, it ensures a smooth transition from a decelerated to an accelerated phase of expansion in the matter dominated regime.

  18. Macroscopic quantum tunneling and the 'cosmic' Josephson effect

    SciTech Connect (OSTI)

    Barone, A. [Dipartimento di Scienze Fisiche, Universita di Napoli 'Federico II', CNR-SPIN, Piazzale Tecchio 21, 80125 Napoli (Italy); Gasperini, M. [Dipartimento di Fisica, Universita di Bari, Via G. Amendola 173, 70126 Bari (Italy); INFN, Sezione di Bari, Bari (Italy); Rotoli, G. [Dipartimento di Ingegneria dell'Informazione, Seconda Universita di Napoli (SUN), Via Roma 29, 81031 Aversa (CE) (Italy)

    2010-10-15T23:59:59.000Z

    We discuss the possible influence of a cosmic magnetic field on the macroscopic quantum tunneling process associated, in a cosmological context, to the decay of the 'false vacuum'. We find a close analogy with the effects of an external magnetic field applied to a Josephson junction in the context of low-temperature/high-temperature superconducting devices.

  19. Short rise time intense electron beam generator

    DOE Patents [OSTI]

    Olson, Craig L. (Albuquerque, NM)

    1987-01-01T23:59:59.000Z

    A generator for producing an intense relativistic electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.

  20. Short rise time intense electron beam generator

    DOE Patents [OSTI]

    Olson, C.L.

    1984-03-16T23:59:59.000Z

    A generator for producing an intense relativisitc electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.

  1. Delivering High IntensityDelivering High Intensity Proton Beam:Proton Beam

    E-Print Network [OSTI]

    McDonald, Kirk

    11 Delivering High IntensityDelivering High Intensity Proton Beam:Proton Beam: Lessons for the NextFACT08NuFACT08 ­­ 4 July4 July S. ChildressS. Childress ­­ Proton BeamsProton Beams 22 Presentation OutlinePresentation Outline Key Proton Beam ConsiderationsKey Proton Beam Considerations The First

  2. Quantitative Infrared Intensity Studies of Vapor-PhaseGlyoxal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Intensity Studies of Vapor-Phase Glyoxal,Methylglyoxal, and 2,3-Butanedione (Diacetyl) with Quantitative Infrared Intensity Studies of Vapor-Phase Glyoxal,Methylglyoxal,...

  3. Absolute integrated intensities of vapor-phase hydrogen peroxide...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Absolute integrated intensities of vapor-phase hydrogen peroxide (H202) in the mid-infrared at atmospheric pressure. Absolute integrated intensities of vapor-phase hydrogen...

  4. EIA Energy Efficiency-Commercial Buildings Sector Energy Intensities...

    U.S. Energy Information Administration (EIA) Indexed Site

    Commercial Buildings Sector Energy Intensities Commercial Buildings Sector Energy Intensities: 1992- 2003 Released Date: December 2004 Page Last Revised: August 2009 These tables...

  5. airglow intensities measured: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mark I 2013-01-01 23 Strongly Intensive Measures for Transverse Momentum and Particle Number Fluctuations Nuclear Experiment (arXiv) Summary: The strongly intensive measures ...

  6. Cosmological Cosmic Rays: Sharpening the Primordial Lithium Problem

    E-Print Network [OSTI]

    Tijana Prodanovic; Brian D. Fields

    2007-09-20T23:59:59.000Z

    Cosmic structure formation leads to large-scale shocked baryonic flows which are expected to produce a cosmological population of structure-formation cosmic rays (SFCRs). Interactions between SFCRs and ambient baryons will produce lithium isotopes via \\alpha+\\alpha \\to ^{6,7}Li. This pre-Galactic (but non-primordial) lithium should contribute to the primordial 7Li measured in halo stars and must be subtracted in order to arrive to the true observed primordial lithium abundance. In this paper we point out that the recent halo star 6Li measurements can be used to place a strong constraint to the level of such contamination, because the exclusive astrophysical production of 6Li is from cosmic-ray interactions. We find that the putative 6Li plateau, if due to pre-Galactic cosmic-ray interactions, implies that SFCR-produced lithium represents Li_{SFCR}/Li_{plateau}\\approx 15% of the observed elemental Li plateau. Taking the remaining plateau Li to be cosmological 7Li, we find a revised (and slightly worsened) discrepancy between the Li observations and Big Bang Nucleosynthesis predictions by a factor of ^7Li_{BBN}/^7Li_{plateau} \\approx 3.7. Moreover, SFCRs would also contribute to the extragalactic gamma-ray background (EGRB) through neutral pion production. This gamma-ray production is tightly related to the amount of lithium produced by the same cosmic rays; the 6Li plateau limits the pre-Galactic (high-redshift) SFCR contribution to be at the level of I_{\\pi_{\\gamma}SFCR}/I_{EGRB} < 5% of the currently observed EGRB.

  7. CMB ISW-lensing bispectrum from cosmic strings

    E-Print Network [OSTI]

    Daisuke Yamauchi; Yuuiti Sendouda; Keitaro Takahashi

    2014-10-21T23:59:59.000Z

    We study the effect of weak lensing by cosmic (super-)strings on the higher-order statistics of the cosmic microwave background (CMB). A cosmic string segment is expected to cause weak lensing as well as an integrated Sachs-Wolfe (ISW) effect, the so-called Gott-Kaiser-Stebbins (GKS) effect, to the CMB temperature fluctuation, which are thus naturally cross-correlated. We point out that, in the presence of such a correlation, yet another kind of the post-recombination CMB temperature bispectra, the ISW-lensing bispectra, will arise in the form of products of the auto- and cross-power spectra. We first present an analytic method to calculate the autocorrelation of the temperature fluctuations induced by the strings, and the cross-correlation between the temperature fluctuation and the lensing potential both due to the string network. In our formulation, the evolution of the string network is assumed to be characterized by the simple analytic model, the velocity-dependent one scale model, and the intercommutation probability is properly incorporated in orderto characterize the possible superstringy nature. Furthermore, the obtained power spectra are dominated by the Poisson-distributed string segments, whose correlations are assumed to satisfy the simple relations. We then estimate the signal-to-noise ratios of the string-induced ISW-lensing bispectra and discuss the detectability of such CMB signals from the cosmic string network. It is found that in the case of the smaller string tension, $G\\mu\\ll 10^{-7}$\\,, the ISW-lensing bispectrum induced by a cosmic string network can constrain the string-model parameters even more tightly than the purely GKS-induced bispectrum in the ongoing and future CMB observations on small scales.

  8. SKA Deep Polarization and Cosmic Magnetism

    E-Print Network [OSTI]

    Taylor, A R; Akahori, Takuya; Beck, Rainer; Gaensler, Bryan; Heald, George; Johnston-Hollitt, Melanie; Langer, Mathieu; Rudnick, Lawrence; Ryu, Dongsu; Scaife, Anna; Schleicher, Dominik; Stil, Jeroen

    2015-01-01T23:59:59.000Z

    Deep surveys with the SKA1-MID array offer for the first time the opportunity to systematically explore the polarization properties of the microJy source population. Our knowledge of the polarized sky approaching these levels is still very limited. In total intensity the population will be dominated by star-forming and normal galaxies to intermediate redshifts ($z \\sim1-2$), and low-luminosity AGN to high redshift. The polarized emission from these objects is a powerful probe of their intrinsic magnetic fields and of their magnetic environments. For redshift of order 1 and above the broad bandwidth of the mid-bands span the Faraday thick and thin regimes allowing study of the intrinsic polarization properties of these objects as well as depolarization from embedded and foreground plasmas. The deep field polarization images will provide Rotation Measures data with very high solid angle density allowing a sensitive statistical analysis of the angular variation of RM on critical arc-minute scales from a magnetic...

  9. Performances of BNL high-intensity synchrotrons

    SciTech Connect (OSTI)

    Weng, W.T.

    1998-03-01T23:59:59.000Z

    The AGS proton synchrotron was completed in 1960 with initial intensity in the 10 to the 10th power proton per pulse (ppp) range. Over the years, through many upgrades and improvements, the AGS now reached an intensity record of 6.3 {times} 10{sup 13} ppp, the highest world intensity record for a proton synchrotron on a single pulse basis. At the same time, the Booster reached 2.2 {times} 10{sup 13} ppp surpassing the design goal of 1.5 {times} 10{sup 13} ppp due to the introduction of second harmonic cavity during injection. The intensity limitation caused by space charge tune spread and its relationship to injection energy at 50 MeV, 200 MeV, and 1,500 MeV will be presented as well as many critical accelerator manipulations. BNL currently participates in the design of an accumulator ring for the SNS project at Oak Ridge. The status on the issues of halo formation, beam losses and collimation are also presented.

  10. MERcury Intense Target (MERIT) Van Graves, ORNL

    E-Print Network [OSTI]

    McDonald, Kirk

    OF ENERGY Airline Hydraulics 28 Oct 2005 Hg System Schematic Double Window (2) Primary Containment SecondaryMERcury Intense Target (MERIT) Overview Van Graves, ORNL Syringe Procurement Kickoff Meeting Airline Hydraulics Bensalem, PA Oct 28, 2005 #12;2 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT

  11. WHERE ARE THE MOST INTENSE THUNDERSTORMS

    E-Print Network [OSTI]

    Nesbitt, Steve

    provided unparalleled information on the global distribution of intense convective storms. T he Tropical-alti- tude, non-sun-synchronous orbit permits sampling throughout the diurnal cycle of precipitation. The cloud-top temperature of storms has been measured using infrared (IR) bright- ness temperature (Tb

  12. Name of Lecture Intensive Thermal Engineering

    E-Print Network [OSTI]

    Name of Lecture Intensive Thermal Engineering Term 2nd semester (October) Units 2-0-0 Lecturers' understanding of the essential part of thermal engineering, comprehensively. The classes are given by three in Thermal Engineering field require the students to have fundamental concepts of thermodynamics and heat

  13. Intense Femtosecond Laser Interactions with Ions in

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ), ultra-short laser light with atoms and molecules has led to the discovery of new phenomena such as bondIntense Femtosecond Laser Interactions with Ions in Beams and Traps A thesis presented through a re-scattering process where an electron is ionized, propagated in the laser field and is driven

  14. Energy Intensity of Agriculture and Food Systems

    E-Print Network [OSTI]

    Wang, Changlu

    dependencies in the light of energy price volatility and concerns as to long-term fossil energy availabilities ENERGY USE. . . . . . . . . . 232 6. FOOD WASTE AND ENERGY USE. . . . . . . . . . . . . Energy Intensity of Agriculture and Food Systems Nathan Pelletier,1 Eric Audsley,2 Sonja Brodt,3

  15. Nonlinear Evolution of Cosmic Magnetic Fields and Cosmic Microwave Background Anisotropies

    E-Print Network [OSTI]

    Hiroyuki Tashiro; Naoshi Sugiyama; Robi Banerjee

    2006-01-14T23:59:59.000Z

    In this work we investigate the effects of the primordial magnetic fields on cosmic microwave background anisotropies (CMB). Based on cosmological magnetohydrodynamic (MHD) simulations we calculate the CMB anisotropy spectra and polarization induced by fluid fluctuations (Alfv\\'en modes) generated by primordial magnetic fields. The strongest effect on the CMB spectra comes from the transition epoch from a turbulent regime to a viscous regime. The balance between magnetic and kinetic energy until the onset of the viscous regime provides a one to one relation between the comoving coherence length $L$ and the comoving magnetic field strength $B$, such as $L \\sim 30 (B/10^{-9}{\\rm G})^3 \\rm pc$. The resulting CMB temperature and polarization anisotropies are somewhat different from the ones previously obtained by using linear perturbation theory. Our calculation gives a constraint on the magnetic field strength in the intermediate scale of CMB observations. Upper limits are set by WMAP and BOOMERANG results for comoving magnetic field strength of $B 0.7 \\rm Mpc$ for the most extreme case, or $B 0.8 \\rm Mpc$ for the most conservative case.

  16. "The Most Hazardous and Dangerous and Greatest Adventure on Which Man Has Ever Embarked": The Frontier in Presidential Pro-Space Discourse, 1957-1963

    E-Print Network [OSTI]

    Leyerzapf, Amy Beth

    2011-12-31T23:59:59.000Z

    “The Most Hazardous and Dangerous and Greatest Adventure on Which Man Has Ever Embarked”: The Frontier in Presidential Pro-Space Discourse, 1957-1963 By Amy Beth Leyerzapf Submitted to the graduate degree program in Communication Studies....D. ________________________________ Dr. Jerry Bailey, Ed.D. Date Defended: September 1, 2011 ii The Dissertation Committee for Amy Beth Leyerzapf certifies that this is the approved version of the following dissertation: “The Most Hazardous and Dangerous...

  17. Neutrino and cosmic-ray release from gamma-ray bursts: Time-dependent simulations

    SciTech Connect (OSTI)

    Asano, Katsuaki [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan); Mészáros, Peter, E-mail: asanok@icrr.u-tokyo.ac.jp, E-mail: nnp@psu.edu [Department of Astronomy and Astrophysics, Department of Physics, Center for Particle and Gravitational Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2014-04-10T23:59:59.000Z

    We revisit the neutrino and ultra-high-energy cosmic-ray (UHECR) production from gamma-ray bursts (GRBs) with time-dependent simulations for the proton-induced cascades. This method can generate self-consistent photon, neutrino, and escaped neutron spectra. To obtain the integrated background spectra, we take into account the distributions of the burst luminosity and pulse duration timescale. A benchmark case with standard GRB luminosity function, a bulk Lorentz factor ? = 300, and a proton to gamma-ray luminosity fraction f{sub p} = 10 is consistent with both the neutrino upper limits and the observed UHECR intensity at ?10{sup 20} eV, while requiring a different type of UHECR source at the ankle. For the benchmark case, the GRBs in the bright end of the luminosity function, which contribute most of the neutrinos, have their photon spectrum substantially distorted by secondary photons. Such bright GRBs are few in number, and reducing their f{sub p} eliminates the distortion and reduces the neutrino production. Even if we neglect the contribution of the brightest GRBs, the UHECR production rate at energies corresponding to the Greisen-Zatsepin-Kuzmin limit is almost unchanged. These nominal GRB models, especially with L {sub iso} ? 10{sup 53} erg s{sup –1}, appear to meet the current constraints as far as being candidate UHECR sources above the ankle energy.

  18. Correlated-Intensity velocimeter for Arbitrary Reflector

    DOE Patents [OSTI]

    Wang, Zhehui (Los Alamos, NM); Luo, Shengnian (Los Alamos, NM); Barnes, Cris W. (Arlington, VA); Paul, Stephen F. (West Orange, NJ)

    2008-11-11T23:59:59.000Z

    A velocimetry apparatus and method comprising splitting incoming reflected laser light and directing the laser light into first and second arms, filtering the laser light with passband filters in the first and second arms, one having a positive passband slope and the other having a negative passband slope, and detecting the filtered laser light via light intensity detectors following the passband filters in the first and second arms

  19. Intensive Variables & Nanostructuring in Magnetostructural Materials

    SciTech Connect (OSTI)

    Lewis, Laura

    2014-08-13T23:59:59.000Z

    Over the course of this project, fundamental inquiry was carried out to investigate, understand and predict the effects of intensive variables, including the structural scale, on magnetostructural phase transitions in the model system of equiatomic FeRh. These transitions comprise simultaneous magnetic and structural phase changes that have their origins in very strong orbital-lattice coupling and thus may be driven by a plurality of effects.

  20. Laser intensity effects in noncommutative QED

    SciTech Connect (OSTI)

    Heinzl, Thomas [School of Computing and Mathematics, University of Plymouth, Plymouth PL4 8AA (United Kingdom); Ilderton, Anton; Marklund, Mattias [Department of Physics, Umeaa University, SE-901 87 Umeaa (Sweden)

    2010-03-01T23:59:59.000Z

    We discuss a twofold extension of QED assuming the presence of strong external fields provided by an ultraintense laser and noncommutativity of spacetime. While noncommutative effects leave the electron's intensity induced mass shift unchanged, photons change significantly in character: they acquire a quasimomentum that is no longer lightlike. We study the consequences of this combined noncommutative strong-field effect for the basic lepton-photon interactions.

  1. Galactic Cosmic Ray Origin Sites: Supernova Remnants and Superbubbles

    E-Print Network [OSTI]

    Bykov, A M; Gladilin, P E; Osipov, S M; 10.1063/1.4772219

    2012-01-01T23:59:59.000Z

    We discuss processes in galactic cosmic ray (GCR) acceleration sites - supernova remnants, compact associations of young massive stars, and superbubbles. Mechanisms of efficient conversion of the mechanical power of the outflows driven by supernova shocks and fast stellar winds of young stars into magnetic fields and relativistic particles are discussed. The high efficiency of particle acceleration in the sources implies the importance of nonlinear feedback effects in a symbiotic relationship where the magnetic turbulence required to accelerate the CRs is created by the accelerated CRs themselves. Non-thermal emission produced by relativistic particles (both those confined in and those that escape from the cosmic accelerators) can be used to constrain the basic physical models of the GCR sources. High resolution X-ray synchrotron imaging, combined with GeV-TeV gamma ray spectra, is a powerful tool to probe the maximum energies of accelerated particles. Future MeV regime spectroscopy will provide unique inform...

  2. Ultra High Energy Cosmic Rays from Decaying Superheavy Particles

    E-Print Network [OSTI]

    V. Berezinsky

    1998-01-08T23:59:59.000Z

    Decaying superheavy particles can be produced by Topological Defects or, in case they are quasi-stable, as relics from the early Universe. The decays of these particles can be the sources of observed Ultra High Energy Cosmic Rays ($E \\sim 10^{10} - 10^{12} GeV$). The Topological Defects as the UHE CR sources are critically reviewed and cosmic necklaces and monopole-antiminopole pairs are identified as most plausible sources. The relic superheavy particles are shown to be clustering in the halo and their decays produce UHE CR without GZK cutoff. The Lightest Supersymmetric Particles with Ultra High Energies are naturally produced in the cascades accompanying the decays of superheavy particles. These particles are discussed as UHE carriers in the Universe.

  3. Ultra high energy cosmic rays from cosmological relics

    E-Print Network [OSTI]

    V. Berezinsky

    1998-11-17T23:59:59.000Z

    Ultra High Energy Cosmic Rays (UHECR) can be a signal from very early (post-inflationary) Universe. At this cosmological epoch Topological Defects (TD) and long-lived suprheavy (SH) particles are expected to be naturally and effectively produced. Both of these relics can produce now the particles, such as protons and photons, with energies in a great excess of what is observed in UHECR, $E \\sim 10^{10} - 10^{11} GeV$. The Topological Defects as the UHECR sources are critically reviewed and cosmic necklaces and monopolonia are identified as most plausible sources. The relic superheavy particles and monopolonia are shown to be clustering in the halo of our Galaxy and their decays produce UHECR without the GZK cutoff. The observational signature of both models are discussed.

  4. A New Measurement of Cosmic Ray Composition at the Knee

    E-Print Network [OSTI]

    K. Boothby; M. Chantell; K. D. Green; D. B. Kieda; J. Knapp; C . G. Larsen; S. P. Swordy

    1997-10-15T23:59:59.000Z

    The Dual Imaging Cerenkov Experiment (DICE) was designed and operated for making elemental composition measurements of cosmic rays near the knee of the spectrum at several PeV. Here we present the first results using this experiment from the measurement of the average location of the depth of shower maximum, , in the atmosphere as a function of particle energy. The value of near the instrument threshold of ~0.1 PeV is consistent with expectations from previous direct measurements. At higher energies there is little change in composition up to ~5 PeV. Above this energy is deeper than expected for a constant elemental composition implying the overall elemental composition is becoming lighter above the knee region. These results disagree with the idea that cosmic rays should become on average heavier above the knee. Instead they suggest a transition to a qualitatively different population of particles above 5 PeV.

  5. Extragalactic Magnetic Field and the Highest Energy Cosmic Rays

    E-Print Network [OSTI]

    Sangjin Lee; Angela Olinto; Guenter Sigl

    1995-08-21T23:59:59.000Z

    The strength and spectrum of the extragalactic magnetic field are still unknown. Its measurement would help answer the question of whether galactic fields are purely a primordial relic or were dynamically enhanced from a much smaller cosmological seed field. In this letter, we show that the composition, spectrum, and directional distribution of extragalactic ultrahigh energy cosmic rays with energies above $\\simeq 10^{18}\\ev$ can probe the large scale component of the extragalactic magnetic field below the present observational upper limit of $10^{-9}$ Gauss. Cosmic ray detectors under construction or currently in the proposal stage should be able to test the existence of the extragalactic magnetic fields on scales of a few to tens of Mpc and strengths in the range $\\simeq 10^{-10} - 10^{-9}$ Gauss.

  6. Diffuse Synchrotron Emission from Galactic Cosmic Ray Electrons

    E-Print Network [OSTI]

    Di Bernardo, Giuseppe; Evoli, Carmelo; Gaggero, Daniele

    2015-01-01T23:59:59.000Z

    Synchrotron diffuse radiation (SDR) emission is one of the major Galactic components, in the 100 MHz up to 100 GHz frequency range. Its spectrum and sky map provide valuable measure of the galactic cosmic ray electrons (GCRE) in the relevant energy range, as well as of the strength and structure of the Galactic magnetic fields (GMF), both regular and random ones. This emission is an astrophysical sky foreground for the study of the Cosmic Microwave Background (CMB), and the extragalactic microwave measurements, and it needs to be modelled as better as possible. In this regard, in order to get an accurate description of the SDR in the Galaxy, we use - for the first time in this context - 3-dimensional GCRE models obtained by running the DRAGON code. This allows us to account for a realistic spiral arm pattern of the source distribution, demanded to get a self-consistent treatment of all relevant energy losses influencing the final synchrotron spectrum.

  7. Non-local bispectra from super cosmic variance

    E-Print Network [OSTI]

    Bayta?, Bekir; Nelson, Elliot; Park, Sohyun; Shandera, Sarah

    2015-01-01T23:59:59.000Z

    We present examples of non-Gaussian statistics that can induce bispectra matching local and non-local (including equilateral) templates in biased sub-volumes. We find cases where the biasing from coupling to long wavelength modes affects only the power spectrum, only the bispectrum or both. Our results suggest that ruling out multi-field scenarios is quite difficult: some measurements of the scalar correlations, including the shape of the bispectrum, can be consistent with single-clock predictions even when cosmic variance from super-horizon modes is at work. Furthermore, if observations of the density perturbations rule out single-clock inflation, we will face a serious cosmic variance obstacle in drawing any further conclusions about the particle physics origin of the scalar fluctuations.

  8. Vortex scattering and intercommuting cosmic strings on a noncommutative spacetime

    SciTech Connect (OSTI)

    Joseph, Anosh; Trodden, Mark [Department of Physics, Syracuse University, Syracuse, New York 13244 (United States); Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, Pennsylvania 19104 (United States)

    2010-02-15T23:59:59.000Z

    We study the scattering of noncommutative vortices, based on the noncommutative field theory developed in [A. P. Balachandran, T. R. Govindarajan, G. Mangano, A. Pinzul, B. A. Qureshi, and ?>S. Vaidya, Phys. Rev. D 75, 045009 (2007).], as a way to understand the interaction of cosmic strings. In the center-of-mass frame, the effects of noncommutativity vanish, and therefore the reconnection of cosmic strings occurs in an identical manner to the commutative case. However, when scattering occurs in a frame other than the center-of-mass frame, strings still reconnect but the well-known 90 deg. scattering no longer need correspond to the head-on collision of the strings, due to the breakdown of Lorentz invariance in the underlying noncommutative field theory.

  9. Constraining invisible neutrino decays with the cosmic microwave background

    SciTech Connect (OSTI)

    Hannestad, Steen; Raffelt, Georg G. [Department of Physics and Astronomy, University of Aarhus, Ny Munkegade, DK-8000 Aarhus C (Denmark); Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Munich (Germany)

    2005-11-15T23:59:59.000Z

    Precision measurements of the acoustic peaks of the cosmic microwave background indicate that neutrinos must be freely streaming at the photon decoupling epoch when T{approx_equal}0.3 eV. This requirement implies restrictive limits on 'secret neutrino interactions', notably on neutrino Yukawa couplings with hypothetical low-mass (pseudo)scalars {phi}. For diagonal couplings in the neutrino mass basis we find g < or approx. 1x10{sup -7}, comparable to limits from supernova 1987A. For the off-diagonal couplings and assuming hierarchical neutrino masses we find g < or approx. 1x10{sup -11}(0.05 eV/m){sup 2} where m is the heavier mass of a given neutrino pair connected by g. This stringent limit excludes that the flavor content of high-energy neutrinos from cosmic-ray sources is modified by {nu}{yields}{nu}{sup '}+{phi} decays on their way to Earth.

  10. [On the jet contribution to the AGN cosmic energy budget

    E-Print Network [OSTI]

    A. Cattaneo; P. N. Best

    2008-12-08T23:59:59.000Z

    Black holes release energy via the production of photons in their accretion discs but also via the acceleration of jets. We investigate the relative importance of these two paths over cosmic time by determining the mechanical luminosity function (LF) of radio sources and by comparing it to a previous determination of the bolometric LF of active galactic nuclei (AGN) from X-ray, optical and infrared observations. The mechanical LF of radio sources is computed in two steps: the determination of the mechanical luminosity as a function of the radio luminosity and its convolution with the radio LF of radio sources. Even with the large uncertainty deriving from the former, we can conclude that the contribution of jets is unlikely to be much larger than 10% of the AGN energy budget at any cosmic epoch.

  11. Testing Cosmic Censorship in Kerr-like Collapse Situations

    E-Print Network [OSTI]

    W. Rudnicki

    1997-10-03T23:59:59.000Z

    According to the cosmic censorship hypothesis of Penrose, naked singularities should never occur in realistic collapse situations. One of the major open problems in this context is the existence of a naked singularity in the Kerr solution with |a|>m; this singularity can be interpreted as the final product of collapse of a rapidly rotating object. Assuming that certain very general and physically reasonable conditions hold, we show here, using the global techniques, that a realistic gravitational collapse of any rotating object, which develops from a regular initial state, cannot lead to the formation of a final state resembling the Kerr solution with a naked singularity. This result supports the validity of the cosmic censorship hypothesis.

  12. Vacuum Polarization on the Schwarzschild Metric with a Cosmic String

    E-Print Network [OSTI]

    Adrian C. Ottewill; Peter Taylor

    2010-06-30T23:59:59.000Z

    We consider the problem of the renormalization of the vacuum polarization in a symmetry space-time with axial but not spherical symmetry, Schwarzschild space-time threaded by an infinite straight cosmic string. Unlike previous calculations, our framework to compute the renormalized vacuum polarization does not rely on special properties of Legendre functions, but rather has been developed in a way that we expect to be applicable to Kerr space-time.

  13. HI Imaging the Low Red-shift Cosmic Web

    E-Print Network [OSTI]

    Robert Braun

    2004-09-09T23:59:59.000Z

    Only in recent years has the realization emerged that galaxies do not dominate the universal baryon budget but are merely the brightest pearls of an underlying Cosmic Web. Although the gas in these inter-galactic filaments is moderately to highly ionized, QSO absorption lines have shown that the surface area increases dramatically in going down to lower HI column densities. The first image of the Cosmic Web in HI emission has just been made of the Local Group filament connecting M31 and M33. The corresponding HI distribution function is in very good agreement with that of the QSO absorption lines, confirming the 30-fold increase in surface area expected between 10^19 cm^-2 and 10^17 cm^-2. The critical observational challenge is crossing the "HI desert", the range of log(N_HI) from about 19.5 down to 18, over which photo-ionization by the intergalactic radiation field produces an exponential decline in the neutral fraction from essentially unity down to a few percent. Nature is kinder again to the HI observer below log(N_HI)=18, where the neutral fraction decreases only very slowly with log(N_HI). With the SKA we can begin the systematic study of the Cosmic Web beyond the Local Group. With moderate integration times, the necessary resolution and sensitivity can be achieved out to distances beyond the Virgo cluster. When combined with targeted optical and UV absorption line observations, the total baryonic masses and enrichment histories of the Cosmic Web will be determined over the complete range of environmental over-densities.

  14. On the strength of the Kerr singularity and cosmic censorship

    E-Print Network [OSTI]

    W. Rudnicki; P. Zieba

    2000-03-16T23:59:59.000Z

    It has been suggested by Israel that the Kerr singularity cannot be strong in the sense of Tipler, for it tends to cause repulsive effects. We show here that, contrary to that suggestion, nearly all null geodesics reaching this singularity do in fact terminate in Tipler's strong curvature singularity. Implications of this result are discussed in the context of an earlier cosmic censorship theorem which constraints the occurrence of Kerr-like naked singularities in generic collapse situations.

  15. Gravitational field of a stationary circular cosmic string loop

    E-Print Network [OSTI]

    A; A. Sen; N. Banerjee

    1998-06-22T23:59:59.000Z

    Gravitational field of a stationary circular cosmic string loop has been studied in the context of full nonlinear Einstein's theory of gravity. It has been assumed that the radial and tangential stresses of the loop are equal to the energy density of the string loop. An exact solution for the system has been presented which has a singularity at a finite distance from the axis,but is regular for any other distances from the axis of the loop.

  16. Conference Summary: The Cosmic Agitator - Magnetic Fields in the Galaxy

    E-Print Network [OSTI]

    T. H. Troland; C. Heiles; A. P. Sarma; G. J. Ferland; R. M. Crutcher; C. L. Brogan

    2008-04-21T23:59:59.000Z

    We present a summary of the conference "The Cosmic Agitator: Magnetic Fields in the Galaxy" held in Lexington KY in 2008 Mar 26-29. The presentation draws primarily from material in the slides prepared for the Conference Summary by one of us (Carl Heiles). Interested readers may navigate to the conference web site given in the paper to view the posted presentations in detail.

  17. Stability of false vacuum in supersymmetric theories with cosmic strings

    SciTech Connect (OSTI)

    Kumar, Brijesh; Yajnik, Urjit A. [Department of Physics, Indian Institute of Technology, Bombay, Mumbai - 400076 (India)

    2009-03-15T23:59:59.000Z

    We study the stability of supersymmetry breaking vacuum in the presence of cosmic strings arising in the messenger sector. For certain ranges of the couplings, the desired supersymmetry breaking vacua become unstable against decay into phenomenologically unacceptable vacua. This sets constraints on the range of allowed values of the coupling constants appearing in the models and more generally on the chosen dynamics of gauge symmetry breaking.

  18. SETI at Planck Energy: When Particle Physicists Become Cosmic Engineers

    E-Print Network [OSTI]

    Brian C. Lacki

    2015-03-05T23:59:59.000Z

    What is the meaning of the Fermi Paradox -- are we alone or is starfaring rare? Can general relativity be united with quantum mechanics? The searches for answers to these questions could intersect. It is known that an accelerator capable of energizing particles to the Planck scale requires cosmic proportions. The energy required to run a Planck accelerator is also cosmic, of order 100 M_sun c^2 for a hadron collider, because the natural cross section for Planck physics is so tiny. If aliens are interested in fundamental physics, they could resort to cosmic engineering for their experiments. These colliders are detectable through the vast amount of "pollution" they produce, motivating a YeV SETI program. I investigate what kinds of radiation they would emit in a fireball scenario, and the feasibility of detecting YeV radiation at Earth, particularly YeV neutrinos. Although current limits on YeV neutrinos are weak, Kardashev 3 YeV neutrino sources appear to be at least 30--100 Mpc apart on average, if they are long-lived and emit isotropically. I consider the feasibility of much larger YeV neutrino detectors, including an acoustic detection experiment that spans all of Earth's oceans, and instrumenting the entire Kuiper Belt. Any detection of YeV neutrinos implies an extraordinary phenomenon at work, whether artificial and natural. Searches for YeV neutrinos from any source are naturally commensal, so a YeV neutrino SETI program has value beyond SETI itself, particularly in limiting topological defects. I note that the Universe is very faint in all kinds of nonthermal radiation, indicating that cosmic engineering is extremely rare.

  19. Cosmic No-Hair Conjecture In Scalar-Tensor Theories

    E-Print Network [OSTI]

    T. Singh; R. Chaubey

    2010-07-08T23:59:59.000Z

    We have shown that, within the context of Scalar-Tensor theories, the anisotropic Bianchi-type cosmological models evolve towards de Sitter universe. A similar result holds in the case of cosmology in Lyra manifold. Thus the analogue of cosmic no-hair theorem of Wald (1983) hold in both the cases. In fact, during inflation there is no difference between scalar-tensor theories, Lyra's manifold and general relativity (GR).

  20. Scalar tensor theory : validity of Cosmic no hair conjecture

    E-Print Network [OSTI]

    Sudeshna Mukerji; Nairwita Mazumder; Ritabrata Biswas; Subenoy Chakraborty

    2011-06-09T23:59:59.000Z

    The paper deals with cosmic no hair conjecture in scalar tensor theory of gravity. Here we have considered both Jordan frame and Einstein frame to examine the conjecture. In Jordan frame, one should restrict both the coupling function of the scalar field and the coupling parameter in addition to the ususal energy conditions for the the matter field for the validity of CNHC while in Einstein frame the restrictions are purely on the energy conditions.

  1. Fundamental constants and cosmic vacuum: the micro and macro connection

    E-Print Network [OSTI]

    Harald Fritzsch; Joan Sola

    2015-03-26T23:59:59.000Z

    The idea that the vacuum energy density $\\rho_{\\Lambda}$ could be time dependent is a most reasonable one in the expanding Universe; in fact, much more reasonable than just a rigid cosmological constant for the entire cosmic history. Being $\\rho_{\\Lambda}=\\rho_{\\Lambda}(t)$ dynamical, it offers a possibility to tackle the cosmological constant problem in its various facets. Furthermore, for a long time (most prominently since Dirac's first proposal on a time variable gravitational coupling) the possibility that the fundamental "constants" of Nature are slowly drifting with the cosmic expansion has been continuously investigated. In the last two decades, and specially in recent times, mounting experimental evidence attests that this could be the case. In this paper, we consider the possibility that these two groups of facts might be intimately connected, namely that the observed acceleration of the Universe and the possible time variation of the fundamental constants are two manifestations of the same underlying dynamics. We call it: the "micro and macro connection", and on its basis we expect that the cosmological term in Einstein's equations, Newton's coupling and the masses of all the particles in the Universe, both the dark matter particles and the ordinary baryons and leptons, should all drift with the cosmic expansion. Here we discuss specific cosmological models realizing such possibility in a way that preserves the principle of covariance of General Relativity.

  2. Imaging the Low Red-shift Cosmic Web

    E-Print Network [OSTI]

    Robert Braun; David Thilker

    2005-01-17T23:59:59.000Z

    The first image of a Cosmic Web, Lyman Limit System has just been made in HI emission within the Local Group filament connecting M31 and M33. The corresponding HI distribution function is in very good agreement with that of the QSO absorption lines, confirming the 30-fold increase in surface area expected between 10^19 cm^-2 and 10^17 cm^-2. The critical observational challenge is crossing the ``HI desert'', the range of log(N_HI) from about 19.5 down to 18, over which photo-ionization by the intergalactic radiation field produces an exponential decline in the neutral fraction from essentially unity down to a few percent. Nature is kinder again to the HI observer below log(N_HI) = 18, where the neutral fraction decreases only very slowly with log(N_HI). Average spectra of the M31/M33 filament suggest a kinetic temperature of 2x10^5 K for the parent ion population, consistent with significant shock-heating. The brightest knot within the filament, with only a 2x10^4 K apparent temperature, is suggestive of localized cooling and condensation. We have initiated two complimentary surveys that should lay the groundwork for a comprehensive study of the Cosmic Web phenomenon in HI emission. When combined with targeted optical and UV absorption line observations, the total baryonic masses and enrichment histories of the Cosmic Web could be determined over the complete range of environmental over-densities.

  3. Radio Cherenkov signals from the Moon: neutrinos and cosmic rays

    E-Print Network [OSTI]

    Yu Seon Jeong; Mary Hall Reno; Ina Sarcevic

    2011-08-11T23:59:59.000Z

    Neutrino production of radio Cherenkov signals in the Moon is the object of radio telescope observations. Depending on the energy range and detection parameters, the dominant contribution to the neutrino signal may come from interactions of the neutrino on the Moon facing the telescope, rather than neutrinos that have traversed a portion of the Moon. Using the approximate analytic expression of the effective lunar aperture from a recent paper by Gayley, Mutel and Jaeger, we evaluate the background from cosmic ray interactions in the lunar regolith. We also consider the modifications to the effective lunar aperture from generic non-standard model neutrino interactions. A background to neutrino signals are radio Cherenkov signals from cosmic ray interactions. For cosmogenic neutrino fluxes, neutrino signals will be difficult to observe because of low neutrino flux at the high energy end and large cosmic ray background in the lower energy range considered here. We show that lunar radio detection of neutrino interactions is best suited to constrain or measure neutrinos from astrophysical sources and probe non-standard neutrino-nucleon interactions such as microscopic black hole production.

  4. Landau Quantization in the Spinning Cosmic String Spacetime

    E-Print Network [OSTI]

    Celio R. Muniz; Valdir B. Bezerra; Marcony S. Cunha

    2014-03-26T23:59:59.000Z

    We analyze the quantum phenomenon arising from the interaction of a spinless charged particle with a rotating cosmic string, under the action of a static and uniform magnetic field parallel to the string. We calculate the energy levels of the particle in the non-relativistic approach, showing how these energies depend on the parameters involved in the problem. In order to do this, we solve the time independent Schroedinger equation in the geometry of the spinning cosmic string, taking into account that the coupling between the rotation of the spacetime and the angular momentum of the particle is very weak, such that makes sense to apply the Schr\\"odinger equation in a curved background whose metric has an off diagonal term which involves time and space. It is also assumed that the particle orbits sufficiently far from the boundary of the region of closed timelike curves which exist around this topological defect. Finally, we find the Landau levels of the particle in the presence of a spinning cosmic string endowed with internal structure, i.e., having finite width and uniformly filled with both material and vacuum energies.

  5. Supernova remnants as cosmic ray accelerators. SNR IC 443

    E-Print Network [OSTI]

    B. Hnatyk; O. Petruk

    1999-02-10T23:59:59.000Z

    We examine the hypothesis that some supernova remnants (SNRs) may be responsible for some unidentified gamma-ray sources detected by EGRET instrument aboard the Compton Gamma Ray Observatory. If this is the case, gamma-rays are produced via pion production and decay from direct inelastic collisions of accelerated by SNR shock wave ultrarelativistic protons with target protons of the interstellar medium. We develop a 3-D hydrodynamical model of SNR IC 443 as a possible cosmic gamma-ray source 2EG J0618+2234. The derived parameters of IC 443: the explosion energy E_o=2.7*10^{50} erg, the initial hydrogen number density n(0)=0.21 cm^{-3}, the mean radius R=9.6 pc and the age t=4500 yr result in too low gamma-ray flux, mainly because of the low explosion energy. Therefore, we investigate in detail the hydrodynamics of IC 443 interaction with a nearby massive molecular cloud and show that the reverse shock wave considerably increases the cosmic ray density in the interaction region. Meantime, the Rayleigh-Taylor instability of contact discontinuity between the SNR and the cloud provides an effective mixing of the containing cosmic ray plasma and the cloud material. We show that the resulting gamma-ray flux is consistent with the observational data.

  6. Can f(T) gravity theories mimic ?CDM cosmic history

    SciTech Connect (OSTI)

    Setare, M.R.; Mohammadipour, N., E-mail: rezakord@ipm.ir, E-mail: N.Mohammadipour@uok.ac.ir [Department of Science, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

    2013-01-01T23:59:59.000Z

    Recently the teleparallel Lagrangian density described by the torsion scalar T has been extended to a function of T. The f(T) modified teleparallel gravity has been proposed as the natural gravitational alternative for dark energy to explain the late time acceleration of the universe. In order to reconstruct the function f(T) by demanding a background ?CDM cosmology we assume that, (i) the background cosmic history provided by the flat ?CDM (the radiation ere with ?{sub eff} = (1/3), matter and de Sitter eras with ?{sub eff} = 0 and ?{sub eff} = ?1, respectively) (ii) the radiation dominate in the radiation era with ?{sub 0r} = 1 and the matter dominate during the matter phases when ?{sub 0m} = 1. We find the cosmological dynamical system which can obey the ?CDM cosmic history. In each era, we find a critical lines that, the radiation dominated and the matter dominated are one points of them in the radiation and matter phases, respectively. Also, we drive the cosmologically viability condition for these models. We investigate the stability condition with respect to the homogeneous scalar perturbations in each era and we obtain the stability conditions for the fixed points in each eras. Finally, we reconstruct the function f(T) which mimics cosmic expansion history.

  7. SETI at Planck Energy: When Particle Physicists Become Cosmic Engineers

    E-Print Network [OSTI]

    Lacki, Brian C

    2015-01-01T23:59:59.000Z

    What is the meaning of the Fermi Paradox -- are we alone or is starfaring rare? Can general relativity be united with quantum mechanics? The searches for answers to these questions could intersect. It is known that an accelerator capable of energizing particles to the Planck scale requires cosmic proportions. The energy required to run a Planck accelerator is also cosmic, of order 100 M_sun c^2 for a hadron collider, because the natural cross section for Planck physics is so tiny. If aliens are interested in fundamental physics, they could resort to cosmic engineering for their experiments. These colliders are detectable through the vast amount of "pollution" they produce, motivating a YeV SETI program. I investigate what kinds of radiation they would emit in a fireball scenario, and the feasibility of detecting YeV radiation at Earth, particularly YeV neutrinos. Although current limits on YeV neutrinos are weak, Kardashev 3 YeV neutrino sources appear to be at least 30--100 Mpc apart on average, if they are ...

  8. Fan-beam intensity modulated proton therapy

    SciTech Connect (OSTI)

    Hill, Patrick [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States)] [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Westerly, David [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Mackie, Thomas [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)] [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques.Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0–255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets.Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage. Overall, the sharp distal falloff of a proton depth-dose distribution was found to provide sufficient control over the dose distribution to meet objectives, even with coarse lateral resolution and channel widths as large as 2 cm. Treatment plans on both phantom and patient data show that dose conformity suffers when treatments are delivered from less than approximately ten angles. Treatment time for a sample prostate delivery is estimated to be on the order of 10 min, and neutron production is estimated to be comparable to that found for existing collimated systems.Conclusions: Fan beam proton therapy is a method of delivering intensity modulated proton therapy which may be employed as an alternative to magnetic scanning systems. A fan beam of protons can be created by a set of quadrupole magnets and modified by a dual-purpose range and intensity modulator. This can be used to deliver inversely planned treatments, with spot intensities optimized to meet user defined dose objectives. Additionally, the ability of a fan beam delivery system to effectively treat multiple beam spots simultaneously may provide advantages as compared to spot scanning deliveries.

  9. Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors

    E-Print Network [OSTI]

    J. Aasi; J. Abadie; B. P. Abbott; R. Abbott; T. Abbott; M. R. Abernathy; T. Accadia; F. Acernese; C. Adams; T. Adams; R. X. Adhikari; C. Affeldt; M. Agathos; N. Aggarwal; O. D. Aguiar; P. Ajith; B. Allen; A. Allocca; E. Amador Ceron; D. Amariutei; R. A. Anderson; S. B. Anderson; W. G. Anderson; K. Arai; M. C. Araya; C. Arceneaux; J. Areeda; S. Ast; S. M. Aston; P. Astone; P. Aufmuth; C. Aulbert; L. Austin; B. E. Aylott; S. Babak; P. T. Baker; G. Ballardin; S. W. Ballmer; J. C. Barayoga; D. Barker; S. H. Barnum; F. Barone; B. Barr; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. Bejger; M. G. Beker; A. S. Bell; C. Bell; I. Belopolski; G. Bergmann; J. M. Berliner; D. Bersanetti; A. Bertolini; D. Bessis; J. Betzwieser; P. T. Beyersdorf; T. Bhadbhade; I. A. Bilenko; G. Billingsley; J. Birch; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; M. Blom; O. Bock; T. P. Bodiya; M. Boer; C. Bogan; C. Bond; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; J. Bowers; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; C. A. Brannen; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; D. D. Brown; F. Brückner; T. Bulik; H. J. Bulten; A. Buonanno; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Calderón Bustillo; E. Calloni; J. B. Camp; P. Campsie; K. C. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; L. Carbone; S. Caride; A. Castiglia; S. Caudill; M. Cavagliá; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; R. Chakraborty; T. Chalermsongsak; S. Chao; P. Charlton; E. Chassande-Mottin; X. Chen; Y. Chen; A. Chincarini; A. Chiummo; H. S. Cho; J. Chow; N. Christensen; Q. Chu; S. S. Y. Chua; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. A. Clark; F. Cleva; E. Coccia; P. -F. Cohadon; A. Colla; M. Colombini; M. Constancio Jr.; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. W. Coughlin; J. -P. Coulon; S. Countryman; P. Couvares; D. M. Coward; M. Cowart; D. C. Coyne; K. Craig; J. D. E. Creighton; T. D. Creighton; S. G. Crowder; A. Cumming; L. Cunningham; E. Cuoco; K. Dahl; T. Dal Canton; M. Damjanic; S. L. Danilishin; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. S. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; G. Debreczeni; J. Degallaix; W. Del Pozzo; E. Deleeuw; S. Deléglise; T. Denker; T. Dent; H. Dereli; V. Dergachev; R. DeRosa; R. DeSalvo; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; A. Di Virgilio; M. Díaz; A. Dietz; K. Dmitry; F. Donovan; K. L. Dooley; S. Doravari; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edwards; A. Effler; P. Ehrens; J. Eichholz; S. S. Eikenberry; G. Endröczi; R. Essick; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Q. Fang; S. Farinon; B. Farr; W. Farr; M. Favata; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Ferrini; F. Fidecaro; L. S. Finn; I. Fiori; R. Fisher; R. Flaminio; E. Foley; S. Foley; E. Forsi; N. Fotopoulos; J. -D. Fournier; S. Franco; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; P. Fritschel; V. V. Frolov; M. -K. Fujimoto; P. Fulda; M. Fyffe; J. Gair; L. Gammaitoni; J. Garcia; F. Garufi; N. Gehrels; G. Gemme; E. Genin; A. Gennai; L. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; S. Gil-Casanova; C. Gill; J. Gleason; E. Goetz; R. Goetz; L. Gondan; G. González; N. Gordon; M. L. Gorodetsky; S. Gossan; S. Goßler; R. Gouaty; C. Graef; P. B. Graff; M. Granata; A. Grant; S. Gras; C. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Griffo; P. Groot; H. Grote; K. Grover; S. Grunewald; G. M. Guidi; C. Guido; K. E. Gushwa; E. K. Gustafson; R. Gustafson; B. Hall; E. Hall; D. Hammer; G. Hammond; M. Hanke; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. Heefner; A. Heidmann; M. Heintze; H. Heitmann; P. Hello; G. Hemming; M. Hendry; I. S. Heng; A. W. Heptonstall; M. Heurs; S. Hild; D. Hoak; K. A. Hodge; K. Holt; M. Holtrop; T. Hong; S. Hooper; T. Horrom; D. J. Hosken; J. Hough; E. J. Howell; Y. Hu; Z. Hua; V. Huang; E. A. Huerta; B. Hughey; S. Husa; S. H. Huttner; M. Huynh; T. Huynh-Dinh; J. Iafrate; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; B. R. Iyer; K. Izumi; M. Jacobson; E. James; H. Jang; Y. J. Jang; P. Jaranowski; F. Jiménez-Forteza; W. W. Johnson; D. Jones; D. I. Jones; R. Jones; R. J. G. Jonker; L. Ju; Haris K; P. Kalmus; V. Kalogera; S. Kandhasamy; G. Kang; J. B. Kanner; M. Kasprzack; R. Kasturi; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kaufman; K. Kawabe; S. Kawamura; F. Kawazoe

    2014-04-07T23:59:59.000Z

    Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension $G\\mu$ below $10^{-8}$ in some regions of the cosmic string parameter space.

  10. Energy Frontier Research Centers: Helping Win the Energy Innovation Race (2011 EFRC Summit Keynote Address, Secretary of Energy Chu)

    ScienceCinema (OSTI)

    Chu, Steven (DOE Secretary of Energy)

    2012-03-14T23:59:59.000Z

    Secretary of Energy Steven Chu gave the keynote address at the 2011 EFRC Summit and Forum. In his talk, Secretary Chu highlighted the need to "unleash America's science and research community" to achieve energy breakthroughs. The 2011 EFRC Summit and Forum brought together the EFRC community and science and policy leaders from universities, national laboratories, industry and government to discuss "Science for our Nation's Energy Future." In August 2009, the Office of Science established 46 Energy Frontier Research Centers. The EFRCs are collaborative research efforts intended to accelerate high-risk, high-reward fundamental research, the scientific basis for transformative energy technologies of the future. These Centers involve universities, national laboratories, nonprofit organizations, and for-profit firms, singly or in partnerships, selected by scientific peer review. They are funded at $2 to $5 million per year for a total planned DOE commitment of $777 million over the initial five-year award period, pending Congressional appropriations. These integrated, multi-investigator Centers are conducting fundamental research focusing on one or more of several ?grand challenges? and use-inspired ?basic research needs? recently identified in major strategic planning efforts by the scientific community. The purpose of the EFRCs is to integrate the talents and expertise of leading scientists in a setting designed to accelerate research that transforms the future of energy and the environment.

  11. Majorana Neutrinos, Neutrino Mass Spectrum and the || ~ 0.001 eV Frontier in Neutrinoless Double Beta Decay

    E-Print Network [OSTI]

    S. Pascoli; S. T. Petcov

    2007-11-30T23:59:59.000Z

    If future neutrino oscillation experiments show that the neutrino mass spectrum is with normal ordering, m1 | > 0.01 eV give negative results, the next frontier in the quest for neutrinoless double beta-decay will correspond to || ~ 0.001 eV. Assuming that massive neutrinos are Majorana particles and their exchange is the dominant mechanism generating neutrinoless double beta-decay, we analise the conditions under which ||, in the case of three neutrino mixing and neutrino mass spectrum with normal ordering, would satisfy || > 0.001 eV. We consider the specific cases of i) normal hierarchical neutrino mass spectrum, ii) of relatively small value of the CHOOZ angle theta13 as well as iii) the general case of spectrum with normal ordering, partial hierarchy and a value of theta13 close to the existing upper limit. We study the ranges of the lightest neutrino mass m1 and/or of sin^2 theta13, for which ||> 0.001 eV and discuss the phenomenological implications of such scenarios. We provide also an estimate of || when the three neutrino masses and the neutrino mixing originate from neutrino mass term of Majorana type for the (left-handed) flavour neutrinos and m1 Ue1^2 + m2 U_e2^2 + m3 Ue3^2 =0, but there does not exist a symmetry which forbids the neutrinoless double beta-decay.

  12. Stresses and fractures in the Frontier Formation, Green River Basin, predicted from basin-margin tectonic element interactions

    SciTech Connect (OSTI)

    Lorenz, J.C.

    1996-01-01T23:59:59.000Z

    Natural fractures and in situ stresses commonly dictate subsurface reservoir permeability and permeability anisotropy, as well as the effectiveness of stimulation techniques in low-permeability, natural gas reservoirs. This paper offers an initial prediction for the orientations of the fracture and stress systems in the tight gas reservoirs of the Frontier Formation, in the Green River basin of southwestern Wyoming. It builds on a previous report that addressed fractures and stresses in the western part of the basin and on ideas developed for the rest of the basin, using the principle that thrust faults are capable of affecting the stress magnitudes and orientations in little-deformed strata several hundreds of kilometers in front of a thrust. The prediction of subsurface stresses and natural fracture orientations is an undertaking that requires the willingness to revise models as definitive data are acquired during drilling. The predictions made in this paper are offered with the caveat that geology in the subsurface is always full of surprises.

  13. Anomaly in the cosmic-ray energy spectrum at GeV-TeV energies

    E-Print Network [OSTI]

    Thoudam, Satyendra

    2015-01-01T23:59:59.000Z

    Recent measurements of cosmic rays by various experiments have found that the energy spectrum of cosmic rays is harder in the TeV region than at GeV energies. The origin of the spectral hardening is not clearly understood. In this paper, we discuss the possibility that the spectral hardening might be due to the effect of re-acceleration of cosmic rays by weak shocks associated with old supernova remnants in the Galaxy.

  14. Is the Energy Density of the Cosmic Quaternionic Field a Possible Candidate for the Black Energy?

    E-Print Network [OSTI]

    V. Majernik

    2003-10-01T23:59:59.000Z

    We try to show that the energy density of the cosmic quaternionic field might be a possible candidate for the black energy.

  15. Intense steady state electron beam generator

    DOE Patents [OSTI]

    Hershcovitch, A.; Kovarik, V.J.; Prelec, K.

    1990-07-17T23:59:59.000Z

    An intense, steady state, low emittance electron beam generator is formed by operating a hollow cathode discharge plasma source at critical levels in combination with an extraction electrode and a target electrode that are operable to extract a beam of fast primary electrons from the plasma source through a negatively biased grid that is critically operated to repel bulk electrons toward the plasma source while allowing the fast primary electrons to move toward the target in the desired beam that can be successfully transported for relatively large distances, such as one or more meters away from the plasma source. 2 figs.

  16. Unique Aspects and Scientific Challenges - Advanced R and D|...

    Office of Science (SC) Website

    Advanced R and D Unique Aspects and Scientific Challenges High Energy Physics (HEP) HEP Home About Research Science Drivers of Particle Physics Energy Frontier Intensity Frontier...

  17. High performance computing and communications: Advancing the frontiers of information technology

    SciTech Connect (OSTI)

    NONE

    1997-12-31T23:59:59.000Z

    This report, which supplements the President`s Fiscal Year 1997 Budget, describes the interagency High Performance Computing and Communications (HPCC) Program. The HPCC Program will celebrate its fifth anniversary in October 1996 with an impressive array of accomplishments to its credit. Over its five-year history, the HPCC Program has focused on developing high performance computing and communications technologies that can be applied to computation-intensive applications. Major highlights for FY 1996: (1) High performance computing systems enable practical solutions to complex problems with accuracies not possible five years ago; (2) HPCC-funded research in very large scale networking techniques has been instrumental in the evolution of the Internet, which continues exponential growth in size, speed, and availability of information; (3) The combination of hardware capability measured in gigaflop/s, networking technology measured in gigabit/s, and new computational science techniques for modeling phenomena has demonstrated that very large scale accurate scientific calculations can be executed across heterogeneous parallel processing systems located thousands of miles apart; (4) Federal investments in HPCC software R and D support researchers who pioneered the development of parallel languages and compilers, high performance mathematical, engineering, and scientific libraries, and software tools--technologies that allow scientists to use powerful parallel systems to focus on Federal agency mission applications; and (5) HPCC support for virtual environments has enabled the development of immersive technologies, where researchers can explore and manipulate multi-dimensional scientific and engineering problems. Educational programs fostered by the HPCC Program have brought into classrooms new science and engineering curricula designed to teach computational science. This document contains a small sample of the significant HPCC Program accomplishments in FY 1996.

  18. Anti-Constitutionalism: Frontiers sans Frontiers

    E-Print Network [OSTI]

    Jackson, Jack

    2012-01-01T23:59:59.000Z

    matter of “state action” and private liberty, the genderedactions of the most well-known guard of the Abu Ghraib prison, Army Private

  19. Compton Process in Intense Short Laser Pulses

    E-Print Network [OSTI]

    K. Krajewska; J. Z. Kaminski

    2012-06-05T23:59:59.000Z

    The spectra of Compton radiation emitted during electron scattering off an intense laser beam are calculated using the framework of strong-field quantum electrodynamics. We model these intense laser beams as finite length plane-wave-fronted pulses, similar to Neville and Rohrlich [Phys. Rev. D {\\bf 3}, 1692 (1971)], or as trains of such pulses. Expressions for energy and angular distributions of Compton photons are derived such that a comparison of both situations becomes meaningful. Comparing frequency distributions for both an isolated laser pulse and a laser pulse train, we find a very good agreement between the results for long pulse durations which breaks down however for ultrashort laser pulses. The dependence of angular distributions of emitted radiation on a pulse duration is also investigated. Pronounced asymmetries of angular distributions are found for very short laser pulses, which gradually disappear with increasing the number of laser field oscillations. Those asymmetries are attributed to asymmetries of the vector potential describing an incident laser beam.

  20. High intensity discharge device containing oxytrihalides

    DOE Patents [OSTI]

    Lapatovich, W.P.; Keeffe, W.M.; Liebermann, R.W.; Maya, J.

    1987-06-09T23:59:59.000Z

    A fill composition for a high intensity discharge device including mercury, niobium oxytrihalide, and a molecular stabilization agent is provided. The molar ratio of niobium oxytrihalide to the molecular stabilization agent in the fill is in the range of from about 5:1 to about 7.5:1. Niobium oxytrihalide is present in the fill in sufficient amount to produce, by dissociation in the discharge, atomic niobium, niobium oxide, NbO, and niobium dioxide, NbO[sub 2], with the molar ratio of niobium-containing vapor species to mercury in the fill being in the range of from about 0.01:1 to about 0.50:1; and mercury pressure of about 1 to about 50 atmospheres at lamp operating temperature. There is also provided a high intensity discharge device comprising a sealed light-transmissive arc tube; the arc tube including the above-described fill; and an energizing means for producing an electric discharge within the arc tube. 7 figs.

  1. ?-Decay in Ultra-Intense Laser Fields

    E-Print Network [OSTI]

    Serban Misicu; Margarit Rizea

    2013-07-05T23:59:59.000Z

    We investigate the \\alpha-decay of a spherical nucleus under the influence of an ultra-intense laser field for the case when the radius vector joining the center-of-masses of the \\alpha-particle and the daughter is aligned with the direction of the external field. The time-independent part of the \\alpha-daughter interaction is taken from elastic scattering compilations whereas the time-varying part describes the interaction between the decaying system with the laser field. The time-dependent Schr\\"odinger equation is solved numerically by appealing to a modified scheme of the Crank-Nicolson type where an additional first-order time derivative appears compared to the field-free case. The tunneling probability of the \\alpha-cluster, and derived quantities (decay rate, total flux) is determined for various laser intensities and frequencies for either continous waves or few-cycle pulses of envelope function F(t)=1. We show that in the latter case pulse sequences containing an odd number of half-cycles determine an enhancement of the tunneling probability compared to the field-free case and the continuous wave case. The present study is carried out taking as example the alpha decaying nucleus $^{106}$Te.

  2. New Frontiers for Organismal Biology Author(s): Dietmar Kltz, David F. Clayton, Gene E. Robinson, Craig Albertson, Hannah V.

    E-Print Network [OSTI]

    Cummings, Molly E.

    , neuroscience, phylogenetics, and eco- logy, and also requires the application of computationally intensive dissection of cause­effect relation- ships between individual genes and their contribution to cellular

  3. China's energy intensity and its determinants at the provincial level

    E-Print Network [OSTI]

    Zhang, Xin, S.M. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    Energy intensity is defined as the amount of energy consumed per dollar of GDP (Gross Domestic Product). The People's Republic of China's (China's) energy intensity has been declining significantly since the late 1970s. ...

  4. Modeling scattered intensity from microspheres in evanescent field

    E-Print Network [OSTI]

    Shah, Suhani Kiran

    2008-10-10T23:59:59.000Z

    of the total scattered light intensity on microsphere size accounts for the scattered intensity distribution in a polydisperse microsphere sample. Understanding this variation in the scattered light with microsphere size will allow improved characterization...

  5. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Sharp, W. M.

    2011-01-01T23:59:59.000Z

    HIFAN 1830 INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMSAC02-05CH11231. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION467 (1992). [38] R. W. Moir, Fusion Tech. 25, 5 (1994) [39

  6. Constraining primordial magnetic fields with future cosmic shear surveys

    SciTech Connect (OSTI)

    Fedeli, C. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Moscardini, L., E-mail: cosimo.fedeli@astro.ufl.edu, E-mail: lauro.moscardini@unibo.it [Dipartimento di Astronomia, Università di Bologna, Via Ranzani 1, 40127 Bologna (Italy)

    2012-11-01T23:59:59.000Z

    The origin of astrophysical magnetic fields observed in galaxies and clusters of galaxies is still unclear. One possibility is that primordial magnetic fields generated in the early Universe provide seeds that grow through compression and turbulence during structure formation. A cosmological magnetic field present prior to recombination would produce substantial matter clustering at intermediate/small scales, on top of the standard inflationary power spectrum. In this work we study the effect of this alteration on one particular cosmological observable, cosmic shear. We adopt the semi-analytic halo model in order to describe the non-linear clustering of matter, and feed it with the altered mass variance induced by primordial magnetic fields. We find that the convergence power spectrum is, as expected, substantially enhanced at intermediate/small angular scales, with the exact amplitude of the enhancement depending on the magnitude and power-law index of the magnetic field power spectrum. Specifically, for a fixed amplitude, the effect of magnetic fields is larger for larger spectral indices. We use the predicted statistical errors for a future wide-field cosmic shear survey, on the model of the ESA Cosmic Vision mission Euclid, in order to forecast constraints on the amplitude of primordial magnetic fields as a function of the spectral index. We find that the amplitude will be constrained at the level of ? 0.1 nG for n{sub B} ? ?3, and at the level of ? 10{sup ?7} nG for n{sub B} ? 3. The latter is at the same level of lower bounds coming from the secondary emission of gamma-ray sources, implying that for high spectral indices Euclid will certainly be able to detect primordial magnetic fields, if they exist. The present study shows how large-scale structure surveys can be used for both understanding the origins of astrophysical magnetic fields and shedding new light on the physics of the pre-recombination Universe.

  7. Constraints on particle dark matter from cosmic-ray antiprotons

    E-Print Network [OSTI]

    N. Fornengo; L. Maccione; A. Vittino

    2015-01-30T23:59:59.000Z

    Cosmic-ray antiprotons represent an important channel for dark matter indirect-detection studies. Current measurements of the antiproton flux at the top of the atmosphere and theoretical determinations of the secondary antiproton production in the Galaxy are in good agreement, with no manifest deviation which could point to an exotic contribution in this channel. Therefore, antiprotons can be used as a powerful tool for constraining particle dark matter properties. By using the spectrum of PAMELA data from 50 MV to 180 GV in rigidity, we derive bounds on the dark matter annihilation cross section (or decay rate, for decaying dark matter) for the whole spectrum of dark matter annihilation (decay) channels and under different hypotheses of cosmic-rays transport in the Galaxy and in the heliosphere. For typical models of galactic propagation, the constraints are significantly strong, setting a lower bound on the dark matter mass of a "thermal" relic at about 50-90 GeV for hadronic annihilation channels. These bounds are enhanced to about 150 GeV on the dark matter mass, when large cosmic-rays confinement volumes in the Galaxy are considered, and are reduced to 4-5 GeV for annihilation to light quarks (no bound for heavy-quark production) when the confinement volume is small. Bounds for dark matter lighter than few tens of GeV are due to the low energy part of the PAMELA spectrum, an energy region where solar modulation is relevant: to this aim, we have implemented a detailed solution of the transport equation in the heliosphere, which allowed us not only to extend bounds to light dark matter, but also to determine the uncertainty on the constraints arising from solar modulation modeling. Finally, we estimate the impact of soon-to-come AMS-02 data on the antiproton constraints.

  8. Global, exact cosmic microwave background data analysis using Gibbs sampling

    SciTech Connect (OSTI)

    Wandelt, Benjamin D. [Department of Physics, UIUC, 1110 W Green Street, Urbana, Illinois 61801 (United States); Department of Astronomy, UIUC, 1002 W Green Street, Urbana, Illinois 61801 (United States); Larson, David L.; Lakshminarayanan, Arun [Department of Physics, UIUC, 1110 W Green Street, Urbana, Illinois 61801 (United States)

    2004-10-15T23:59:59.000Z

    We describe an efficient and exact method that enables global Bayesian analysis of cosmic microwave background (CMB) data. The method reveals the joint posterior density (or likelihood for flat priors) of the power spectrum C{sub l} and the CMB signal. Foregrounds and instrumental parameters can be simultaneously inferred from the data. The method allows the specification of a wide range of foreground priors. We explicitly show how to propagate the non-Gaussian dependency structure of the C{sub l} posterior through to the posterior density of the parameters. If desired, the analysis can be coupled to theoretical (cosmological) priors and can yield the posterior density of cosmological parameter estimates directly from the time-ordered data. The method does not hinge on special assumptions about the survey geometry or noise properties, etc., It is based on a Monte Carlo approach and hence parallelizes trivially. No trace or determinant evaluations are necessary. The feasibility of this approach rests on the ability to solve the systems of linear equations which arise. These are of the same size and computational complexity as the map-making equations. We describe a preconditioned conjugate gradient technique that solves this problem and demonstrate in a numerical example that the computational time required for each Monte Carlo sample scales as n{sub p}{sup 3/2} with the number of pixels n{sub p}. We use our method to analyze the data from the Differential Microwave Radiometer on the Cosmic Background Explorer and explore the non-Gaussian joint posterior density of the C{sub l} from the Differential Microwave Radiometer on the Cosmic Background Explorer in several projections.

  9. The Local Dimension: a method to quantify the Cosmic Web

    E-Print Network [OSTI]

    Prakash Sarkar; Somnath Bharadwaj

    2008-12-09T23:59:59.000Z

    It is now well accepted that the galaxies are distributed in filaments, sheets and clusters all of which form an interconnected network known as the Cosmic Web. It is a big challenge to quantify the shapes of the interconnected structural elements that form this network. Tools like the Minkowski functionals which use global properties, though well suited for an isolated object like a single sheet or filament, are not suited for an interconnected network of such objects. We consider the Local Dimension $D$, defined through $N(R)=A R^D$, where $N(R)$ is the galaxy number count within a sphere of comoving radius $R$ centered on a particular galaxy, as a tool to locally quantify the shape in the neigbourhood of different galaxies along the Cosmic Web. We expect $D \\sim 1,2$ and 3 for a galaxy located in a filament, sheet and cluster respectively. Using LCDM N-body simulations we find that it is possible to determine $D$ through a power law fit to $N(R)$ across the length-scales 2 to $10 {\\rm Mpc}$ for $\\sim 33 %$ of the galaxies. We have visually identified the filaments and sheets corresponding to many of the galaxies with $D \\sim 1$ and 2 respectively. In several other situations the structure responsible for the $D$ value could not be visually identified, either due to its being tenuous or due to other dominating structures in the vicinity. We also show that the global distribution of the $D$ values can be used to visualize and interpret how the different structural elements are woven into the Cosmic Web.

  10. Spacetime noncommutativity and ultrahigh energy cosmic ray experiments

    SciTech Connect (OSTI)

    Horvat, Raul; Kekez, Dalibor; Trampetic, Josip [Physics Division, Rudjer Boskovic Institute, Zagreb (Croatia)

    2011-03-15T23:59:59.000Z

    If new physics were capable of pushing the neutrino-nucleon inelastic cross section 3 orders of magnitude beyond the standard model prediction, then ultrahigh energy (UHE) neutrinos would have already been observed at neutrino observatories. We use such a constraint to reveal information on the scale of noncommutativity (NC) {Lambda}{sub NC} in noncommutative gauge field theories where neutrinos possess a tree-level coupling to photons in a generation-independent manner. In the energy range of interest (10{sup 10} to 10{sup 11} GeV), the {theta} expansion (|{theta}|{approx}1/{Lambda}{sub NC}{sup 2}) and, therefore, the perturbative expansion, in terms of {Lambda}{sub NC}, retains no longer its meaningful character, forcing us to resort to those NC field theoretical frameworks involving the full {theta} resummation. Our numerical analysis of the contribution to the process coming from the photon exchange impeccably pins down a lower bound on {Lambda}{sub NC} to be as high as 900 (450) TeV, depending on the estimates for the cosmogenic neutrino flux. If, on the other hand, one considers a surprising recent result that occurred in Pierre Auger Observatory data, that UHE cosmic rays are mainly composed of highly ionized Fe nuclei, then our bounds get weaker, due to the diminished cosmic neutrino flux. Nevertheless, we show that, even for the very high fraction of heavy nuclei in primary UHE cosmic rays, our method may still yield remarkable bounds on {Lambda}{sub NC}, typically always above 200 TeV. Albeit, in this case, one encounters a maximal value for the Fe fraction, from which any useful information on {Lambda}{sub NC} can be drawn, delimiting thus the applicability of our method.

  11. Cosmic Ray Spectral Deformation Caused by Energy Determination Errors

    E-Print Network [OSTI]

    Per Carlson; Conny Wannemark

    2005-05-10T23:59:59.000Z

    Using simulation methods, distortion effects on energy spectra caused by errors in the energy determination have been investigated. For cosmic ray proton spectra, falling steeply with kinetic energy E as E-2.7, significant effects appear. When magnetic spectrometers are used to determine the energy, the relative error increases linearly with the energy and distortions with a sinusoidal form appear starting at an energy that depends significantly on the error distribution but at an energy lower than that corresponding to the Maximum Detectable Rigidity of the spectrometer. The effect should be taken into consideration when comparing data from different experiments, often having different error distributions.

  12. Statistical Tools for Analyzing the Cosmic Ray Energy Spectrum

    E-Print Network [OSTI]

    J. D. Hague; B. R. Becker; M. S. Gold; J. A. J. Matthews

    2008-08-20T23:59:59.000Z

    In this paper un-binned statistical tools for analyzing the cosmic ray energy spectrum are developed and illustrated with a simulated data set. The methods are designed to extract accurate and precise model parameter estimators in the presence of statistical and systematic energy errors. Two robust methods are used to test for the presence of flux suppression at the highest energies: the Tail-Power statistic and a likelihood ratio test. Both tests give evidence of flux suppression in the simulated data. The tools presented can be generalized for use on any astrophysical data set where the power-law assumption is relevant and can be used to aid observational design.

  13. The force exerting on cosmic bodies in a quaternionc field

    E-Print Network [OSTI]

    V. Majernik

    2003-09-03T23:59:59.000Z

    The expression of a time-dependent cosmological constant $\\lambda \\propto 1/t^2$ is interpreted as the energy density of a special type of the quaternionic field. The Lorenz-like force acting on the moving body in the presence of this quaternionic field is determined. The astronomical and terrestrial effects of this field are presented, and the ways how it can be observably detected is discussed. Finally, a new mechanism of the particle creation and an alternative cosmological scenario in the presence of the cosmic quatertionic field is suggested.

  14. Cosmic-Ray Hardenings in the Light of AMS-02

    E-Print Network [OSTI]

    Ohira, Yutaka; Ioka, Kunihito

    2015-01-01T23:59:59.000Z

    Recent precise observations of cosmic rays (CRs) by AMS-02 experiment clearly show (1) harder spectra of helium and carbon compared to protons by $\\propto R^{0.08}$, and (2) concave breaks in proton and helium spectra at a rigidity $R \\sim 300$ GV. In particular the helium and carbon spectra are exactly similar, pointing to the same acceleration site. We examine possible interpretations of these features and identify a chemically enriched region, that is, superbubbles as the most probable origin of Galactic CRs. We further show that CRs originate primarily from the supernova ejecta in the superbubble core, mixed with negligible interstellar medium, and predict similar spectra for heavy nuclei.

  15. Gamma-Ray Bursts and Quantum Cosmic Censorship

    E-Print Network [OSTI]

    T. P. Singh

    1998-05-17T23:59:59.000Z

    Gamma-ray bursts are believed to result from the coalescence of binary neutron stars. However, the standard proposals for conversion of the gravitational energy to thermal energy have difficulties. We show that if the merger of the two neutron stars results in a naked singularity, instead of a black hole, the ensuing quantum particle creation can provide the requisite thermal energy in a straightforward way. The back-reaction of the created particles can avoid the formation of the naked singularity predicted by the classical theory. Hence cosmic censorship holds in the quantum theory, even if it were to be violated in classical general relativity.

  16. Magnetic helicity generation from the cosmic axion field

    SciTech Connect (OSTI)

    Campanelli, L.; Giannotti, M. [Dipartimento di Fisica, Universita di Ferrara, I-44100 Ferrara (Italy); INFN-Sezione di Ferrara, I-44100 Ferrara (Italy)

    2005-12-15T23:59:59.000Z

    The coupling between a primordial magnetic field and the cosmic axion field generates a helical component of the magnetic field around the time in which the axion starts to oscillate. If the energy density of the seed magnetic field is comparable to the energy density of the universe at that time, then the resulting magnetic helicity is about vertical bar H{sub B} vertical bar {approx_equal}(10{sup -20}G){sup 2} kpc and remains constant after its generation. As a corollary, we find that the standard properties of the oscillating axion remain unchanged even in the presence of very strong magnetic fields.

  17. Magnetic Helicity Generation from the Cosmic Axion Field

    E-Print Network [OSTI]

    L. Campanelli; M. Giannotti

    2005-12-12T23:59:59.000Z

    The coupling between a primordial magnetic field and the cosmic axion field generates a helical component of the magnetic field around the time in which the axion starts to oscillate. If the energy density of the seed magnetic field is comparable to the energy density of the universe at that time, then the resulting magnetic helicity is about |H_B| \\simeq (10^{-20} G)^2 kpc and remains constant after its generation. As a corollary, we find that the standard properties of the oscillating axion remain unchanged even in the presence of very strong magnetic fields.

  18. The case against scaling defect models of cosmic structure formation

    E-Print Network [OSTI]

    Andreas Albrecht; Richard A. Battye; James Robinson

    1997-07-11T23:59:59.000Z

    We calculate predictions from defect models of structure formation for both the matter and Cosmic Microwave Background (CMB) over all observable scales. Our results point to a serious problem reconciling the observed large-scale galaxy distribution with the COBE normalization, a result which is robust for a wide range of defect parameters. We conclude that standard scaling defect models are in conflict with the data, and show how attempts to resolve the problem by considering non-scaling defects would require radical departures from the standard scaling picture.

  19. First Structure Formation: II. Cosmic String + Hot Dark Matter Models

    E-Print Network [OSTI]

    Tom Abel; Albert Stebbins; Peter Anninos; Michael L. Norman

    1997-06-26T23:59:59.000Z

    We examine the structure of baryonic wakes in the cosmological fluid which would form behind GUT-scale cosmic strings at early times (redshifts z > 100) in a neutrino-dominated universe. We show, using simple analytical arguments as well as 1- and 2-dimensional hydrodynamical simulations, that these wakes will NOT be able to form interesting cosmological objects before the neutrino component collapses. The width of the baryonic wakes (< 10 kpc comoving) is smaller than the scale of wiggles on the strings and are probably not enhanced by the wiggliness of the string network.

  20. Marginal evidence for cosmic acceleration from Type Ia supernovae

    E-Print Network [OSTI]

    Nielsen, Jeppe Trøst; Sarkar, Subir

    2015-01-01T23:59:59.000Z

    The `standard' model of cosmology is founded on the basis that the expansion rate of the universe is accelerating at present --- as was inferred originally from the Hubble diagram of Type Ia supernovae. There exists now a much bigger database of supernovae so we can perform rigorous statistical tests to check whether these `standardisable candles' indeed indicate cosmic acceleration. Taking account of the empirical procedure by which corrections are made to their absolute magnitudes to allow for the varying shape of the light curve and extinction by dust, we find, rather surprisingly, that the data are still quite consistent with a constant rate of expansion.