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1

Positrons for linear colliders  

SciTech Connect (OSTI)

The requirements of a positron source for a linear collider are briefly reviewed, followed by methods of positron production and production of photons by electromagnetic cascade showers. Cross sections for the electromagnetic cascade shower processes of positron-electron pair production and Compton scattering are compared. A program used for Monte Carlo analysis of electromagnetic cascades is briefly discussed, and positron distributions obtained from several runs of the program are discussed. Photons from synchrotron radiation and from channeling are also mentioned briefly, as well as positron collection, transverse focusing techniques, and longitudinal capture. Computer ray tracing is then briefly discussed, followed by space-charge effects and thermal heating and stress due to showers. (LEW)

Ecklund, S.

1987-11-01T23:59:59.000Z

2

[New technology for linear colliders  

SciTech Connect (OSTI)

This report discusses the following topics on research of microwave amplifiers for linear colliders: Context in current microwave technology development; gated field emission for microwave cathodes; cathode fabrication and tests; microwave cathode design using field emitters; and microwave localization.

McIntyre, P.M.

1992-08-12T23:59:59.000Z

3

Prospects of Heavy Neutrino Searches at Future Lepton Colliders  

E-Print Network [OSTI]

We discuss the future prospects of heavy neutrino searches at next generation lepton colliders. In particular, we focus on the planned electron-positron colliders, operating in two different beam modes, namely, $e^+e^-$ and $e^-e^-$. In the $e^+e^-$ beam mode, we consider various production and decay modes of the heavy neutrino ($N$), and find that the final state with $e+2j+\\slashed{E}$, arising from the $e^+e^-\\to N\

Banerjee, Shankha; Ibarra, Alejandro; Mandal, Tanumoy; Mitra, Manimala

2015-01-01T23:59:59.000Z

4

International Workshop on Linear Colliders 2010  

ScienceCinema (OSTI)

IWLC2010 International Workshop on Linear Colliders 2010ECFA-CLIC-ILC joint meeting: Monday 18 October - Friday 22 October 2010Venue: CERN and CICG (International Conference Centre Geneva, Switzerland) This year, the International Workshop on Linear Colliders organized by the European Committee for Future Accelerators (ECFA) will study the physics, detectors and accelerator complex of a linear collider covering both CLIC and ILC options.Contact Workshop Secretariat  IWLC2010 is hosted by CERN

None

2011-10-06T23:59:59.000Z

5

Subcritical Fission Reactor Based on Linear Collider  

E-Print Network [OSTI]

The beams of Linear Collider after main collision can be utilized to build an accelerator--driven sub--critical reactor.

I. F. Ginzburg

2005-07-29T23:59:59.000Z

6

Siting the International Linear Collider at Hanford  

SciTech Connect (OSTI)

Review of the proposed International Linear Collider, applications in high energy physics, and evaluation of the Hanford Site as a possible location for siting the facilityl.

Kouzes, Richard T.; Asner, David M.; Brodzinski, Ronald L.; Fast, James E.; Miley, Harry S.

2012-03-15T23:59:59.000Z

7

Siting the International Linear Collider at Hanford  

SciTech Connect (OSTI)

Review of the proposed International Linear Collider, applications in high energy physics, and evaluation of the Hanford Site as a possible location for siting the facility.

Kouzes, Richard T.; Asner, David M.; Brodzinski, Ronald L.; Fast, James E.; Miley, Harry S.

2012-05-01T23:59:59.000Z

8

TESLA*HERA as Lepton (Photon)-Hadron Collider  

E-Print Network [OSTI]

New facilities for particle and nuclear physics research, which will be available due to constructing the TESLA linear electron-positron collider tangentially to the HERA proton ring, are discussed.

O. Yavas; A. K. Ciftci; S. Sultansoy

2000-04-11T23:59:59.000Z

9

2009 Linear Collider Workshop of the Americas  

SciTech Connect (OSTI)

The 2009 Linear Collider Workshop of the Americas was held on the campus of the University of New Mexico from 29 September to 3 October, 2009. This was a joint meeting of the American Linear Collider Physics Group and the ILC Global Design Effort. Two hundred fifty people attended. The number of scientific contributions was 333. The complete agenda, with links to all of the presentations, is available at physics.unm.edu/LCWA09/. The meeting brought together international experts as well as junior scientists, to discuss the physics potential of the linear collider and advances in detector technology. The validation of detector designs was announced, and the detector design groups planned the next phase of the effort. Detector R&D teams reported on progress on many topics including calorimetry and tracking. Recent accelerator design considerations were discussed in a special session for experimentalists and theorists.

Seidel, Sally

2009-09-29T23:59:59.000Z

10

QCD Interconnection Studies at Linear Colliders  

E-Print Network [OSTI]

Heavy objects like the W, Z and t are short-lived compared with typical hadronization times. When pairs of such particles are produced, the subsequent hadronic decay systems may therefore become interconnected. We study such potential effects at Linear Collider energies.

Valery A. Khoze; Torbjörn Sjöstrand

1999-12-10T23:59:59.000Z

11

Towards a Future Linear Collider and The Linear Collider Studies at CERN  

ScienceCinema (OSTI)

During the week 18-22 October, more than 400 physicists will meet at CERN and in the CICG (International Conference Centre Geneva) to review the global progress towards a future linear collider. The 2010 International Workshop on Linear Colliders will study the physics, detectors and accelerator complex of a linear collider covering both the CLIC and ILC options. Among the topics presented and discussed will be the progress towards the CLIC Conceptual Design Report in 2011, the ILC Technical Design Report in 2012, physics and detector studies linked to these reports, and an increasing numbers of common working group activities. The seminar will give an overview of these topics and also CERN?s linear collider studies, focusing on current activities and initial plans for the period 2011-16. n.b: The Council Chamber is also reserved for this colloquium with a live transmission from the Main Auditorium.

None

2011-10-06T23:59:59.000Z

12

Linear Collider Physics Resource Book Snowmass 2001  

SciTech Connect (OSTI)

The American particle physics community can look forward to a well-conceived and vital program of experimentation for the next ten years, using both colliders and fixed target beams to study a wide variety of pressing questions. Beyond 2010, these programs will be reaching the end of their expected lives. The CERN LHC will provide an experimental program of the first importance. But beyond the LHC, the American community needs a coherent plan. The Snowmass 2001 Workshop and the deliberations of the HEPAP subpanel offer a rare opportunity to engage the full community in planning our future for the next decade or more. A major accelerator project requires a decade from the beginning of an engineering design to the receipt of the first data. So it is now time to decide whether to begin a new accelerator project that will operate in the years soon after 2010. We believe that the world high-energy physics community needs such a project. With the great promise of discovery in physics at the next energy scale, and with the opportunity for the uncovering of profound insights, we cannot allow our field to contract to a single experimental program at a single laboratory in the world. We believe that an e{sup +}e{sup -} linear collider is an excellent choice for the next major project in high-energy physics. Applying experimental techniques very different from those used at hadron colliders, an e{sup +}e{sup -} linear collider will allow us to build on the discoveries made at the Tevatron and the LHC, and to add a level of precision and clarity that will be necessary to understand the physics of the next energy scale. It is not necessary to anticipate specific results from the hadron collider programs to argue for constructing an e{sup +}e{sup -} linear collider; in any scenario that is now discussed, physics will benefit from the new information that e{sup +}e{sup -} experiments can provide. This last point merits further emphasis. If a new accelerator could be designed and built in a few years, it would make sense to wait for the results of each accelerator before planning the next one. Thus, we would wait for the results from the Tevatron before planning the LHC experiments, and wait for the LHC before planning any later stage. In reality accelerators require a long time to construct, and they require such specialized resources and human talent that delay can cripple what would be promising opportunities. In any event, we believe that the case for the linear collider is so compelling and robust that we can justify this facility on the basis of our current knowledge, even before the Tevatron and LHC experiments are done. The physics prospects for the linear collider have been studied intensively for more than a decade, and arguments for the importance of its experimental program have been developed from many different points of view. This book provides an introduction and a guide to this literature. We hope that it will allow physicists new to the consideration of linear collider physics to start from their own personal perspectives and develop their own assessments of the opportunities afforded by a linear collider.

Ronan (Editor), M.T.

2001-06-01T23:59:59.000Z

13

International linear collider reference design report  

SciTech Connect (OSTI)

The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

Aarons, G.

2007-06-22T23:59:59.000Z

14

A High Intensity Linear e+ e- Collider Facility at Low Energy  

E-Print Network [OSTI]

I discuss a proposal for a high intensity $e^+e^-$ linear collider operated at low center of mass energies $\\sqrt{s}intensity beams. Such a facility would provide high statistics samples of (charmed) vector mesons and would permit searches for LFV with unprecedented precision in decays of $\\tau$ leptons and mesons. Implications on the design of the linear accelerator are discussed together with requirements to achieve luminosities of $10^{35}$ cm$^{-2}$s$^{-1}$ or more.

A. Schoning

2006-10-23T23:59:59.000Z

15

Single Anomalous Production of the Fourth SM Family Leptons at Future e+e-, ep and pp Colliders  

SciTech Connect (OSTI)

Possible single productions of fourth SM family charged and neutral leptons via anomalous interactions at the future e+e-, ep, and pp colliders are studied. Signatures of such anomalous processes are argued at above colliders comparatively.

Ciftci, A. K. [Physics Department, Faculty of Sciences, Ankara University, 06100 Tandogan, Ankara (Turkey); Ciftci, R.; Karadeniz, H. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar, Ankara (Turkey); Sultansoy, S. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar, Ankara (Turkey); Institute of Physics, Academy of Sciences, H. Cavid Avenue 33, Baku (Azerbaijan); Yildiz, H. Duran [Physics Department, Faculty of Sciences and Arts, Dumlupinar University, Merkez Campus, Kutahya (Turkey)

2007-04-23T23:59:59.000Z

16

Physics at the e+ e- Linear Collider  

E-Print Network [OSTI]

A comprehensive review of physics at an e+e- Linear Collider in the energy range of sqrt{s}=92 GeV--3 TeV is presented in view of recent and expected LHC results, experiments from low energy as well as astroparticle physics.The report focuses in particular on Higgs boson, Top quark and electroweak precision physics, but also discusses several models of beyond the Standard Model physics such as Supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analyzed as well.

Moortgat-Pick, G; Battaglia, M; Belanger, G; Fujii, K; Kalinowski, J; Heinemeyer, S; Kiyo, Y; Olive, K; Simon, F; Uwer, P; Wackeroth, D; Zerwas, P M; Arbey, A; Asano, M; Bechtle, P; Bharucha, A; Brau, J; Brummer, F; Choi, S Y; Denner, A; Desch, K; Dittmaier, S; Ellis, J; Ellwanger, U; Englert, C; Freitas, A; Ginzburg, I; Godfrey, S; Greiner, N; Grojean, C; Grunewald, M; Heisig, J; Hocker, A; Kanemura, S; Kawagoe, K; Kogler, R; Krawczyk, M; Kronfeld, A S; Kroseberg, J; Liebler, S; List, J; Mahmoudi, F; Mambrini, Y; Matsumoto, S; Mnich, J; Monig, K; Muhlleitner, M M; Poschl, R; Porod, W; Porto, S; Rolbiecki, K; Schlatter, D; Schmitt, M; Serpico, P; Stanitzki, M; Stål, O; Stefaniak, T; Stockinger, D; Wagner, A; Weiglein, G; Wilson, G W; Zeune, L; Moortgat, F; Xella, S

2015-01-01T23:59:59.000Z

17

Physics at the e+ e- Linear Collider  

E-Print Network [OSTI]

A comprehensive review of physics at an e+e- Linear Collider in the energy range of sqrt{s}=92 GeV--3 TeV is presented in view of recent and expected LHC results, experiments from low energy as well as astroparticle physics.The report focuses in particular on Higgs boson, Top quark and electroweak precision physics, but also discusses several models of beyond the Standard Model physics such as Supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analyzed as well.

G. Moortgat-Pick; H. Baer; M. Battaglia; G. Belanger; K. Fujii; J. Kalinowski; S. Heinemeyer; Y. Kiyo; K. Olive; F. Simon; P. Uwer; D. Wackeroth; P. M. Zerwas; A. Arbey; M. Asano; P. Bechtle; A. Bharucha; J. Brau; F. Brummer; S. Y. Choi; A. Denner; K. Desch; S. Dittmaier; U. Ellwanger; C. Englert; A. Freitas; I. Ginzburg; S. Godfrey; N. Greiner; C. Grojean; M. Grunewald; J. Heisig; A. Hocker; S. Kanemura; K. Kawagoe; R. Kogler; M. Krawczyk; A. S. Kronfeld; J. Kroseberg; S. Liebler; J. List; F. Mahmoudi; Y. Mambrini; S. Matsumoto; J. Mnich; K. Monig; M. M. Muhlleitner; R. Poschl; W. Porod; S. Porto; K. Rolbiecki; M. Schmitt; P. Serpico; M. Stanitzki; O. Stål; T. Stefaniak; D. Stockinger; G. Weiglein; G. W. Wilson; L. Zeune; F. Moortgat; S. Xella

2015-04-07T23:59:59.000Z

18

Detecting exotic heavy leptons at the large hadron collider.  

E-Print Network [OSTI]

the cuts actually slightly increases with mass due to the longer time delays. 0.01 0.1 1 10 100 1000 100 200 300 400 500 600 700 800 900 1000 Cr os s se ct io n (fb ) Mass of heavy lepton (GeV) Before applying cuts After applying cuts Figure 5: Cross...

Allanach, B C; Harris, Chris M; Parker, Michael A; Richardson, P; Webber, Bryan R

19

A 233 km tunnel for lepton and hadron colliders  

SciTech Connect (OSTI)

A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of e{sup +}e{sup -}, pp-bar , and {mu}{sup +}{mu}{sup -} collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV e{sup +}e{sup -} colliders employ Crab Waist Crossings, ultra low emittance damped bunches, short vertical IP focal lengths, superconducting RF, and low coercivity, grain oriented silicon steel/concrete dipoles. Some details are also provided for a high luminosity 240 GeV e{sup +}e{sup -} collider and 1.75 TeV muon accelerator in a Fermilab site filler tunnel. The 40 TeV pp-bar collider uses the high intensity Fermilab p-bar source, exploits high cross sections for pp-bar production of high mass states, and uses 2 Tesla ultra low carbon steel/YBCO superconducting magnets run with liquid neon. The 35 TeV muon ring ramps the 2 Tesla superconducting magnets at 9 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 1.75 to 17.5 TeV in 63 orbits with 71% survival, and mitigates neutrino radiation with phase shifting, roller coaster motion in a FODO lattice.

Summers, D. J.; Cremaldi, L. M.; Datta, A.; Duraisamy, M.; Luo, T.; Lyons, G. T. [Dept. of Physics and Astronomy, University of Mississippi-Oxford, University, MS 38677 (United States)

2012-12-21T23:59:59.000Z

20

Governance of the International Linear Collider Project  

SciTech Connect (OSTI)

Governance models for the International Linear Collider Project are examined in the light of experience from similar international projects around the world. Recommendations for one path which could be followed to realize the ILC successfully are outlined. The International Linear Collider (ILC) is a unique endeavour in particle physics; fully international from the outset, it has no 'host laboratory' to provide infrastructure and support. The realization of this project therefore presents unique challenges, in scientific, technical and political arenas. This document outlines the main questions that need to be answered if the ILC is to become a reality. It describes the methodology used to harness the wisdom displayed and lessons learned from current and previous large international projects. From this basis, it suggests both general principles and outlines a specific model to realize the ILC. It recognizes that there is no unique model for such a laboratory and that there are often several solutions to a particular problem. Nevertheless it proposes concrete solutions that the authors believe are currently the best choices in order to stimulate discussion and catalyze proposals as to how to bring the ILC project to fruition. The ILC Laboratory would be set up by international treaty and be governed by a strong Council to whom a Director General and an associated Directorate would report. Council would empower the Director General to give strong management to the project. It would take its decisions in a timely manner, giving appropriate weight to the financial contributions of the member states. The ILC Laboratory would be set up for a fixed term, capable of extension by agreement of all the partners. The construction of the machine would be based on a Work Breakdown Structure and value engineering and would have a common cash fund sufficiently large to allow the management flexibility to optimize the project's construction. Appropriate contingency, clearly apportioned at both a national and global level, is essential if the project is to be realised. Finally, models for running costs and decommissioning at the conclusion of the ILC project are proposed. This document represents an interim report of the bodies and individuals studying these questions inside the structure set up and supervised by the International Committee for Future Accelerators (ICFA). It represents a request for comment to the international community in all relevant disciplines, scientific, technical and most importantly, political. Many areas require further study and some, in particular the site selection process, have not yet progressed sufficiently to be addressed in detail in this document. Discussion raised by this document will be vital in framing the final proposals due to be published in 2012 in the Technical Design Report being prepared by the Global Design Effort of the ILC.

Foster, B.; /Oxford U.; Barish, B.; /Caltech; Delahaye, J.P.; /CERN; Dosselli, U.; /INFN, Padua; Elsen, E.; /DESY; Harrison, M.; /Brookhaven; Mnich, J.; /DESY; Paterson, J.M.; /SLAC; Richard, F.; /Orsay, LAL; Stapnes, S.; /CERN; Suzuki, A.; /KEK, Tsukuba; Wormser, G.; /Orsay, LAL; Yamada, S.; /KEK, Tsukuba

2012-05-31T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Klystron switching power supplies for the Internation Linear Collider  

SciTech Connect (OSTI)

The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

Fraioli, Andrea; /Cassino U. /INFN, Pisa

2009-12-01T23:59:59.000Z

22

Background Simulations for the International Linear Collider  

E-Print Network [OSTI]

on superconducting technology to collide bunches of electrons and positrons. The baseline configuration (about 31 km in a clean experimental environment with low backgrounds. The LHC will likely discover the Higgs boson accelerator directly. DESY FLC, 22603 Hamburg, Germany, adrian.vogel@desy.de 1 #12;Figure 1: Overall view

23

Power Saving Optimization for Linear Collider Interaction Region Parameters  

SciTech Connect (OSTI)

Optimization of Interaction Region parameters of a TeV energy scale linear collider has to take into account constraints defined by phenomena such as beam-beam focusing forces, beamstrahlung radiation, and hour-glass effect. With those constraints, achieving a desired luminosity of about 2E34 would require use of e{sup +}e{sup -} beams with about 10 MW average power. Application of the 'travelling focus' regime may allow the required beam power to be reduced by at least a factor of two, helping reduce the cost of the collider, while keeping the beamstrahlung energy loss reasonably low. The technique is illustrated for the 500 GeV CM parameters of the International Linear Collider. This technique may also in principle allow recycling the e{sup +}e{sup -} beams and/or recuperation of their energy.

Seryi, Andrei; /SLAC

2009-10-30T23:59:59.000Z

24

Physics Beyond the Standard Model: Exotic Leptons and Black Holes at Future Colliders  

E-Print Network [OSTI]

The Standard Model of particle physics has been remarkably successful in describing present experimental results. However, it is assumed to be only a low-energy effective theory which will break down at higher energy scales, theoretically motivated to be around 1 TeV. There are a variety of proposed models of new physics beyond the Standard Model, most notably supersymmetric and extra dimension models. New charged and neutral heavy leptons are a feature of a number of theories of new physics, including the `intermediate scale' class of supersymmetric models. Using a time-of-flight technique to detect the charged leptons at the Large Hadron Collider, the discovery range (in the particular scenario studied in the first part of this thesis) is found to extend up to masses of 950 GeV. Extra dimension models, particularly those with large extra dimensions, allow the possible experimental production of black holes. The remainder of the thesis describes some theoretical results and computational tools necessary to model the production and decay of these miniature black holes at future particle colliders. The grey-body factors which describe the Hawking radiation emitted by higher-dimensional black holes are calculated numerically for the first time and then incorporated in a Monte Carlo black hole event generator; this can be used to model black hole production and decay at next-generation colliders. It is hoped that this generator will allow more detailed examination of black hole signatures and help to devise a method for extracting the number of extra dimensions present in nature.

Christopher M. Harris

2005-02-01T23:59:59.000Z

25

LINEAR COLLIDER PHYSICS RESOURCE BOOK FOR SNOWMASS 2001.  

SciTech Connect (OSTI)

The American particle physics community can look forward to a well-conceived and vital program of experimentation for the next ten years, using both colliders and fixed target beams to study a wide variety of pressing questions. Beyond 2010, these programs will be reaching the end of their expected lives. The CERN LHC will provide an experimental program of the first importance. But beyond the LHC, the American community needs a coherent plan. The Snowmass 2001 Workshop and the deliberations of the HEPAP subpanel offer a rare opportunity to engage the full community in planning our future for the next decade or more. A major accelerator project requires a decade from the beginning of an engineering design to the receipt of the first data. So it is now time to decide whether to begin a new accelerator project that will operate in the years soon after 2010. We believe that the world high-energy physics community needs such a project. With the great promise of discovery in physics at the next energy scale, and with the opportunity for the uncovering of profound insights, we cannot allow our field to contract to a single experimental program at a single laboratory in the world. We believe that an e{sup +}e{sup {minus}} linear collider is an excellent choice for the next major project in high-energy physics. Applying experimental techniques very different from those used at hadron colliders, an e{sup +}e{sup {minus}} linear collider will allow us to build on the discoveries made at the Tevatron and the LHC, and to add a level of precision and clarity that will be necessary to understand the physics of the next energy scale. It is not necessary to anticipate specific results from the hadron collider programs to argue for constructing an e{sup +}e{sup {minus}} linear collider; in any scenario that is now discussed, physics will benefit from the new information that e{sup +}e{sup {minus}} experiments can provide.

ABE,T.; DAWSON,S.; HEINEMEYER,S.; MARCIANO,W.; PAIGE,F.; TURCOT,A.S.; ET AL

2001-05-03T23:59:59.000Z

26

RF properties of periodic accelerating structures for linear colliders  

SciTech Connect (OSTI)

With the advent of the SLAC electron-positron linear collider (SLC) in the 100 GeV center-of-mass energy range, research and development work on even higher energy machines of this type has started in several laboratories in the United States, Europe, the Soviet Union and Japan. These linear colliders appear to provide the only promising approach to studying e/sup /plus//e/sup /minus// physics at center-of-mass energies approaching 1 TeV. This thesis concerns itself with the study of radio frequency properties of periodic accelerating structures for linear colliders and their interaction with bunched beams. The topics that have been investigated are: experimental measurements of the energy loss of single bunches to longitudinal modes in two types of structures, using an equivalent signal on a coaxial wire to simulate the beam; a method of canceling the energy spread created within a single bunch by longitudinal wakefields, through appropriate shaping of the longitudinal charge distribution of the bunch; derivation of the complete transient beam-loading equation for a train of bunches passing through a constant-gradient accelerator section, with application to the calculation and minimization of multi-bunch energy spread; detailed study of field emission and radio frequency breakdown in disk-loaded structures at S-, C- and X-band frequencies under extremely high-gradient conditions, with special attention to thermal effects, radiation, sparking, emission of gases, surface damage through explosive emission and its possible control through RF-gas processing. 53 refs., 49 figs., 9 tabs.

Wang, J.W.

1989-07-01T23:59:59.000Z

27

Effects of R-parity violating supersymmetry in top pair production at linear colliders with polarized beams  

E-Print Network [OSTI]

In the minimal supersymmetric standard model with R-parity violation, the lepton number violating top quark interactions can contribute to the top pair production at a linear collider via tree-level u-channel squark exchange diagrams. We calculate such contributions and find that in the allowed range of these R-violating couplings, the top pair production rate as well as the top quark polarization and the forward-backward asymmetry can be significantly altered. By comparing the unpolarized beams with the polarized beams, we find that the polarized beams are more powerful in probing such new physics.

Xuelei Wang; Jitao Li; Suzhen Liu

2006-11-06T23:59:59.000Z

28

Reliability and Maintainability Issues for the Next Linear Collider  

SciTech Connect (OSTI)

Large accelerators for high energy physics research traditionally have been designed using informal best design, engineering, and management practices to achieve acceptable levels of operational availability. However, the Next Linear Collider(NLC) project presents a particular challenge for operational availability due to the unprecedented size and complexity of the accelerator systems required to achieve the physics goals of high center-of-mass energy and high luminosity. Formal reliability and maintainability analysis, design, and implementation will be required to achieve acceptable operational availability for the high energy physics research program. This paper introduces some of the basic concepts of reliability analysis and applies them to the 2.6-cm microwave power system of the two 10-km-long, 250-GeV linacs that are currently proposed for the NLC design.

Wilson, Zane J.; Gold, Saul L.; Koontz, Ron F.; Lavine, Ted L.; /SLAC

2011-08-26T23:59:59.000Z

29

Physics Reach at Future Colliders  

SciTech Connect (OSTI)

The physics reach at future colliders is discussed, with focus on the Higgs sector. First we present the Standard Model and some results obtained at the existing high-energy hadron collider, Tevatron, together with the corresponding expectations for the Large Hadron Collider (LHC), which starts operating in 2008. Then we discuss important low energy measurements: the anomalous magnetic moment for muon and the leptonic B-decay together with b{yields}s{gamma}. Finally the potential of the planned e{sup +}e{sup -} International Linear Collider (ILC) and its possible option Photon Linear Collider (PLC), e{gamma} and {gamma}{gamma}, is shortly presented.

Krawczyk, Maria [Institute of Theoretical Physics, University of Warsaw, ul. Hoz-dota 69, 00-681 Warsaw (Poland); CERN, CH-1211 Geneva 23 (Switzerland)

2007-11-27T23:59:59.000Z

30

Phenomenology of the minimal $B-L$ Model: the Higgs sector at the Large Hadron Collider and future Linear Colliders  

E-Print Network [OSTI]

This Thesis is devoted to the study of the phenomenology of the Higgs sector of the minimal $B-L$ extension of the Standard Model at present and future colliders. Firstly, the motivations that call for the minimal $B-L$ extension are summarised. In addition, the model is analysed in its salient parts. Moreover, a detailed review of the phenomenological allowed Higgs sector parameter space is given. Finally, a complete survey of the distinctive Higgs boson signatures of the model at both the Large Hadron Collider and the future linear colliders is presented.

Giovanni Marco Pruna

2011-06-23T23:59:59.000Z

31

DAPNIA/SEA-00-15 TESLA Linear Collider : Status Report  

E-Print Network [OSTI]

DAPNIA/SEA-00-15 TESLA Linear Collider : Status Report O. Napoly for the TESLA Collaboration CEA) October 24-28, 2000, FNAL, Batavia, IL, USA #12;#12;TESLA Linear Collider : Status Report O. Napoly for the TESLA Collaboration CEA/Saclay, DAPNIA/SEA 91191 Gif-sur-Yvette, FRANCE Abstract. We review the current

32

International Linear Collider-A Technical Progress Report  

SciTech Connect (OSTI)

The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of the work reported here and will contain all the elements needed to propose the ILC to collaborating governments, including a technical design and implementation plan that are realistic and have been better optimised for performance, cost and risk. We are on track to develop detailed plans for the ILC, such that once results from the Large Hadron Collider (LHC) at CERN establish the main science goals and parameters of the next machine, we will be in good position to make a strong proposal for this new major global project in particle physics. The two overriding issues for the ILC R&D programme are to demonstrate that the technical requirements for the accelerator are achievable with practical technologies, and that the ambitious physics goals can be addressed by realistic ILC detectors. This GDE interim report documents the impressive progress on the accelerator technologies that can make the ILC a reality. It highlights results of the technological demonstrations that are giving the community increased confidence that we will be ready to proceed with an ILC project following the TDR. The companion detector and physics report document likewise demonstrates how detector designs can meet the ambitious and detailed physics goals set out by the ILC Steering Committee. LHC results will likely affect the requirements for the machine design and the detectors, and we are monitoring that very closely, intending to adapt our design as those results become available.

Elsen, Eckhard; /DESY; Harrison, Mike; /Brookhaven; Hesla, Leah; /Fermilab; Ross, Marc; /Fermilab; Royole-Degieux, Perrine; /Paris, IN2P3; Takahashi, Rika; /KEK, Tsukuba; Walker, Nicholas; /DESY; Warmbein, Barbara; /DESY; Yamamoto, Akira; /KEK, Tsukuba; Yokoya, Kaoru; /KEK, Tsukuba; Zhang, Min; /Beijing, Inst. High Energy Phys.

2011-11-04T23:59:59.000Z

33

Neutralino Production and Decay at an e^+e^- Linear Collider with Transversely Polarized Beams  

E-Print Network [OSTI]

Once supersymmetric neutralinos chi^0 are produced copiously at e^+e^- linear colliders, their characteristics can be measured with high precision. In particular, the fundamental parameters in the gaugino/higgsino sector of the minimal supersymmetric extension of the standard model (MSSM) can be analyzed. Here we focus on the determination of possible CP-odd phases of these parameters. To that end, we exploit the electron/positron beam polarization, including transverse polarization, as well as the spin/angular correlations of the neutralino production e^+ e^- to chi^0_i chi^0_j and subsequent 2-body decays chi^0_i to chi^0_k h, chi^0_k Z, \\tilde \\ell^\\pm_R \\ell^\\mp, using (partly) optimized CP-odd observables. If no final-state polarizations are measured, the Z and h modes are independent of the chi^0_i polarization, but CP-odd observables constructed from the leptonic decay mode can help in reconstructing the neutralino sector of the CP-noninvariant MSSM. However, transverse beam polarization does not seem ...

Choi, S Y; Song, J

2006-01-01T23:59:59.000Z

34

TESLA Linear-Collider Projekt Abbildung 134: Das hydrogeologische Profil entlang der TESLA-Trasse. Der TESLA-  

E-Print Network [OSTI]

TESLA Linear-Collider Projekt Abbildung 134: Das hydrogeologische Profil entlang der TESLA-Trasse. Der TESLA- Tunnel liegt in wasserdurchlässigen und -undurchlässigen Schichten. Die wasserdurch gesättigt. 230 #12;TESLA Linear-Collider Projekt Voruntersuchungen zum TESLA Linear-Collider Projekt Ein

35

Acclerator R&D for a Linear Collider  

SciTech Connect (OSTI)

The goal of this project was to perform simulations of beam transport in linear colliders, with an emphasis on emittance dilution, spin polarization transport, and development and testing of beam based tuning algorithms. Our simulations are based on an existing object-oriented particle-tracking library, Bmad. To facilitate the efficient development of simulations, an accelerator design and analysis program based on Bmad has been developed called Tao (Tool for Accelerator Optics). The three beam-based alignment algorithms, Dispersion Free Steering, Ballistic Alignment (BA), and the Kubo Method have been implemented in Tao. We have studied the effects of magnet misalignments, BPM resolution, beam jitter, stray fields, BPM and steering magnet failure and the effects of various cavity shape wakefields. A parametric study has been conducted in the presence of the above types of errors for all three alignment algorithms. We find that BPM resolution has only modest impact on the effectiveness of beam based alignment. The DFS correction algorithm was found to be very robust in situations where there were BPM and/or steering magnet failures. The wakefields in the main linac are very weak and cause negligible emittance growth. Spin tracking was extended to study all accelerator components between the damping ring and the interaction point, including RF cavities and the helical undulator. We find that there is no significant depolarization in the RTML, main linac or beam delivery system and that the polarization is relatively insensitive to misalignment. We have developed an effective spin rotator. During the final year of the grant we exploited the computing power of our new linux cluster, along with the modeling codes that we had developed, to investigate damping ring physics and design, specifically as it relates to the CESR Test Accelerator project.

Rubin, D.L.; Dugan, G.; Gibbons, L.; Palmer, M.; Patterson, R.; Sagan, D.; Smith, J.C.; Tenenbaum, P.; Woodley, M.; Fields, J.; Urban, J.

2008-11-26T23:59:59.000Z

36

[New technology for linear colliders]. Annual progress report and renewal proposal  

SciTech Connect (OSTI)

This report discusses the following topics on research of microwave amplifiers for linear colliders: Context in current microwave technology development; gated field emission for microwave cathodes; cathode fabrication and tests; microwave cathode design using field emitters; and microwave localization.

McIntyre, P.M.

1992-08-12T23:59:59.000Z

37

Of Linear Colliders, the GDE Workshop at Bangalore, Mughals, Camels, Elephants and Sundials  

SciTech Connect (OSTI)

In this colloquium, the speaker will give a summary of the recent International Linear Collider (ILC) Global Design Effort (GDE) Workshop at Bangalore and how the High Energy Physics community converged to this meeting after many years of electron-positron linear collider design and experimental work. Given that this workshop for the first time took place in India, the speaker will also show a few pictures and talk briefly about what he learned in that fascinating country.

Loew, Greg

2006-04-17T23:59:59.000Z

38

Vibration Stabilization of a Mechanical Model of a X-Band Linear Collider Final Focus Magnet  

SciTech Connect (OSTI)

The small beam sizes at the interaction point of a X-band linear collider require mechanical stabilization of the final focus magnets at the nanometer level. While passive systems provide adequate performance at many potential sites, active mechanical stabilization is useful if the natural or cultural ground vibration is higher than expected. A mechanical model of a room temperature linear collider final focus magnet has been constructed and actively stabilized with an accelerometer based system.

Frisch, Josef; Chang, Allison; Decker, Valentin; Doyle, Eric; Eriksson, Leif; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Partridge, Richard; Seryi, Andrei; /SLAC

2006-09-28T23:59:59.000Z

39

Pair Production of Tau Sneutrinos at Linear Colliders  

E-Print Network [OSTI]

The pair production of tau sneutrinos in $e^{+}e^{-}$ collisions and their subsequent decays are studied in a framework of the supersymmetric extension of the standard model. We present an analysis for the parameter space (BR vs. mass) which could be explored at the future high energy $e^{+}e^{-}$ colliders.

V. Ari; O. Cakir

2010-07-15T23:59:59.000Z

40

Detectors for Linear Colliders: Calorimetry at a Future Electron-Positron Collider (3/4)  

ScienceCinema (OSTI)

Calorimetry will play a central role in determining the physics reach at a future e+e- collider. The requirements for calorimetry place the emphasis on achieving an excellent jet energy resolution. The currently favoured option for calorimetry at a future e+e- collider is the concept of high granularity particle flow calorimetry. Here granularity and a high pattern recognition capability is more important than the single particle calorimetric response. In this lecture I will describe the recent progress in understanding the reach of high granularity particle flow calorimetry and the related R&D; efforts which concentrate on test beam demonstrations of the technological options for highly granular calorimeters. I will also discuss alternatives to particle flow, for example the technique of dual readout calorimetry.

None

2011-10-06T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Observable T{sub 7} Lepton Flavor Symmetry at the Large Hadron Collider  

SciTech Connect (OSTI)

More often than not, models of flavor symmetry rely on the use of nonrenormalizable operators (in the guise of flavons) to accomplish the phenomenologically successful tribimaximal mixing of neutrinos. We show instead how a simple renormalizable two-parameter neutrino mass model of tribimaximal mixing can be constructed with the non-Abelian discrete symmetry T{sub 7} and the gauging of B-L. This is also achieved without the addition of auxiliary symmetries and particles present in almost all other proposals. Most importantly, it is verifiable at the Large Hadron Collider.

Cao Qinghong [High Energy Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States); Khalil, Shaaban [Centre for Theoretical Physics, British University in Egypt, El Sherouk City, Postal No. 11837, P.O. Box 43 (Egypt); Department of Mathematics, Ain Shams University, Faculty of Science, Cairo 11566 (Egypt); Ma, Ernest [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States); Okada, Hiroshi [Centre for Theoretical Physics, British University in Egypt, El Sherouk City, Postal No. 11837, P.O. Box 43 (Egypt)

2011-04-01T23:59:59.000Z

42

Collider Detector at Fermilab (CDF): Data from W, Z bosons and Drell Yan lepton pairs research of the CDF Electroweak Group  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The Electroweak group studies production and properties of W, Z bosons and Drell Yan lepton pairs. Their public web page makes data and numerous figures available from both CDF Runs I and II.

43

Lepton number violating processes mediated by Majorana neutrinos at hadron colliders  

SciTech Connect (OSTI)

We study the lepton number violating like-sign dilepton processes h{sub 1}h{sub 2}{yields}l{sup {+-}}l{sup '{+-}}jjX and h{sub 1}h{sub 2}{yields}l{sup {+-}}l{sup '{+-}}W{sup {+-}}X, mediated by heavy GeV scale Majorana neutrinos. We focus on the resonantly enhanced contributions with a nearly on-mass-shell Majorana neutrino in the s channel. We study the constraints on like-sign dilepton production at the Tevatron and the LHC on the basis of the existing experimental limits on the masses of heavy neutrinos and their mixings U{sub {alpha}}{sub N} with {alpha}={nu}{sub e}, {nu}{sub {mu}}, {nu}{sub {tau}}. Special attention is paid to the constraints from neutrinoless double beta decay. We note that searches for like-sign e{sup {+-}}e{sup {+-}} events at Tevatron and LHC may provide evidence of CP violation in the neutrino sector. We also discuss the conditions under which it is possible to extract individual constraints on the mixing matrix elements in a model independent way.

Kovalenko, Sergey; Lu Zhun; Schmidt, Ivan [Departamento de Fisica, Universidad Tecnica Federico, Santa Maria, Casilla 110-V, Valparaiso (Chile) and Center of Subatomic Physics, Valparaiso (Chile)

2009-10-01T23:59:59.000Z

44

CONSTRAINTS ON LASER-DRIVEN ACCELERATORS FOR A HIGH-ENERGY LINEAR COLLIDER*  

E-Print Network [OSTI]

CONSTRAINTS ON LASER-DRIVEN ACCELERATORS FOR A HIGH-ENERGY LINEAR COLLIDER* J.S. Wurtele and AV on 1 TeV) are applied to free-space laser and laser/plasma accelerators. It is shown that the requirements impose very severe constraints upon the new accelerators-- so severe, that it seems unlikely

Wurtele, Jonathan

45

Long ion chamber systems for the SLC (Stanford Linear Collider)  

SciTech Connect (OSTI)

A Panofsky Long Ion Chamber (PLIC) is essentially a gas-filled coaxial cable, and has been used to protect the Stanford Linear Accelerator from damage caused by its electron beam, and as a sensitive diagnostic tool. This old technology has been updated and has found renewed use in the SLC. PLIC systems have been installed as beam steering aids in most parts of the SLC and are a part of the system that protects the SLC from damage by errant beams in several places. 5 refs., 3 figs., 1 tab.

Rolfe, J.; Gearhart, R.; Jacobsen, R.; Jenkins, T.; McComick, D.; Nelson, R.; Reagan, D.; Ross, M.

1989-03-01T23:59:59.000Z

46

Proceedings of the Lepton Photon 2009  

E-Print Network [OSTI]

a linear collider complementing the LHC remains at the top of the list of future projects, other smaller projects have gathered momentum like ultra high intensity Super B-factories, charm factories, and others Proceedings of the 24th International Symposium on Lepton and Photon Interactions at High Energies 2009

47

Construction and testing of a large scale prototype of a silicon tungsten electromagnetic calorimeter for a future lepton collider  

E-Print Network [OSTI]

The CALICE collaboration is preparing large scale prototypes of highly granular calorimeters for detectors to be operated at a future linear electron positron collider. After several beam campaigns at DESY, CERN and FNAL, the CALICE collaboration has demonstrated the principle of highly granular electromagnetic calorimeters with a first prototype called physics prototype. The next prototype, called technological prototype, addresses the engineering challenges which come along with the realisation of highly granular calorimeters. This prototype will comprise 30 layers where each layer is composed of four 9_9 cm2 silicon wafers. The front end electronics is integrated into the detector layers. The size of each pixel is 5_5 mm2. This prototype enter sits construction phase. We present results of the first layers of the technological prototype obtained during beam test campaigns in spring and summer 2012. According to these results the signal over noise ratio of the detector exceeds the R&D goal of10:1.

Rouëné,J

2013-01-01T23:59:59.000Z

48

Assessing Risk in Costing High-energy Accelerators: from Existing Projects to the Future Linear Collider  

E-Print Network [OSTI]

High-energy accelerators are large projects funded by public money, developed over the years and constructed via major industrial contracts both in advanced technology and in more conventional domains such as civil engineering and infrastructure, for which they often constitute one-of markets. Assessing their cost, as well as the risk and uncertainty associated with this assessment is therefore an essential part of project preparation and a justified requirement by the funding agencies. Stemming from the experience with large circular colliders at CERN, LEP and LHC, as well as with the Main Injector, the Tevatron Collider Experiments and Accelerator Upgrades, and the NOvA Experiment at Fermilab, we discuss sources of cost variance and derive cost risk assessment methods applicable to the future linear collider, through its two technical approaches for ILC and CLIC. We also address disparities in cost risk assessment imposed by regional differences in regulations, procedures and practices.

Lebrun, Philippe

2010-01-01T23:59:59.000Z

49

Final Report for the UNIVERSITY-BASED DETECTOR RESEARCH AND DEVELOPMENT FOR THE INTERNATIONAL LINEAR COLLIDER  

SciTech Connect (OSTI)

The U.S Linear Collider Detector R&D program, supported by the DOE and NSF umbrella grants to the University of Oregon, made significant advances on many critical aspects of the ILC detector program. Progress advanced on vertex detector sensor development, silicon and TPC tracking, calorimetry on candidate technologies, and muon detection, as well as on beamline measurements of luminosity, energy, and polarization.

Brau, James E [Univ. of Oregon] [Univ. of Oregon

2013-04-22T23:59:59.000Z

50

Off-shell effects in Higgs processes at a linear collider and implications for the LHC  

E-Print Network [OSTI]

The importance of off-shell contributions is discussed for $H\\to VV^{(*)}$ with $V\\in\\{Z,W\\}$ for large invariant masses $m_{VV}$ involving a standard model (SM)-like Higgs boson with $m_H=125$GeV at a linear collider (LC). Both dominant production processes $e^+e^-\\to ZH\\to ZVV^{(*)}$ and $e^+e^-\\to\

Stefan Liebler; Gudrid Moortgat-Pick; Georg Weiglein

2015-02-27T23:59:59.000Z

51

Off-shell effects in Higgs processes at a linear collider and implications for the LHC  

E-Print Network [OSTI]

The importance of off-shell contributions is discussed for $H\\to VV^{(*)}$ with $V\\in\\{Z,W\\}$ for large invariant masses $m_{VV}$ involving a standard model (SM)-like Higgs boson with $m_H=125$GeV at a linear collider (LC). Both dominant production processes $e^+e^-\\to ZH\\to ZVV^{(*)}$ and $e^+e^-\\to\

Liebler, Stefan; Weiglein, Georg

2015-01-01T23:59:59.000Z

52

A modified post damping ring bunch compressor beamline for the TESLA linear collider  

SciTech Connect (OSTI)

We propose a modified bunch compressor beamline, downstream of the damping ring, for the TESLA linear collider. This modified beamline uses a third harmonic radio-frequency section based on the 3.9 GHz superconducting cavity under development at Fermilab. In our design the beam deceleration is about {approx}50 MeV instead of {approx}450 MeV in the original design proposed.

Philippe R.-G. Piot; Winfried Decking

2004-03-23T23:59:59.000Z

53

Improving estimates of the number of fake leptons and other mis-reconstructed objects in hadron collider events: BoB's your UNCLE  

E-Print Network [OSTI]

J H E P 1 1 ( 2 0 1 4 ) 0 3 1 Published for SISSA by Springer Received: July 30, 2014 Revised: September 29, 2014 Accepted: October 20, 2014 Published: November 6, 2014 Improving estimates of the number of ‘fake’ leptons and other mis... -reconstructed objects in hadron collider events: BoB’s your UNCLE1 Thomas P.S. Gillam and Christopher G. Lester Dept of Physics, Cavendish Laboratory, JJ Thomson Avenue, Cambridge, CB3 0HE, U.K. E-mail: gillam@hep.phy.cam.ac.uk, lester@hep.phy.cam.ac.uk Abstract: We...

Gillam, Thomas P.S.; Lester, Christopher G.

2014-11-06T23:59:59.000Z

54

Effective Yukawa couplings and flavor-changing Higgs boson decays at linear colliders  

SciTech Connect (OSTI)

We analyze the advantages of a linear-collider program for testing a recent theoretical proposal where the Higgs boson Yukawa couplings are radiatively generated, keeping unchanged the standard-model mechanism for electroweak-gauge-symmetry breaking. Fermion masses arise at a large energy scale through an unknown mechanism, and the standard model at the electroweak scale is regarded as an effective field theory. In this scenario, Higgs boson decays into photons and electroweak gauge-boson pairs are considerably enhanced for a light Higgs boson, which makes a signal observation at the LHC straightforward. On the other hand, the clean environment of a linear collider is required to directly probe the radiative fermionic sector of the Higgs boson couplings. Also, we show that the flavor-changing Higgs boson decays are dramatically enhanced with respect to the standard model. In particular, we find a measurable branching ratio in the range (10{sup -4}-10{sup -3}) for the decay H{yields}bs for a Higgs boson lighter than 140 GeV, depending on the high-energy scale where Yukawa couplings vanish. We present a detailed analysis of the Higgs boson production cross sections at linear colliders for interesting decay signatures, as well as branching-ratio correlations for different flavor-conserving/nonconserving fermionic decays.

Gabrielli, E. [CERN, PH-TH, CH-1211 Geneva 23 (Switzerland); Mele, B. [INFN, Sezione di Roma, c/o Dipartimento di Fisica, Universita di Roma 'La Sapienza', Piazzale A. Moro 2, I-00185 Rome (Italy)

2011-04-01T23:59:59.000Z

55

Proceedings of the workshop on new kinds of positron sources for linear colliders  

SciTech Connect (OSTI)

It has been very clear from the beginning of studies for future linear colliders that the conventional positron source approach, as exemplified by the SLC source, is pushing uncomfortably close to the material limits of the conversion target. Nonetheless, since this type of positron source is better understood and relatively inexpensive to build, it has been incorporated into the initial design studies for the JLC/NLC. New ideas for positron sources for linear colliders have been regularly reported in the literature and at accelerator conferences for at least a decade, and indeed the recirculation scheme associated with the VLEPP design is nearly two decades old. Nearly all the new types of positron sources discussed in this workshop come under the heading of crystals (or channeling), undulators, and Compton. Storage ring and nuclear reactor sources were not discussed. The positron source designs that were discussed have varying degrees of maturity, but except for the case of crystal sources, where proof of principle experiments have been undertaken, experimental results are missing. It is hoped that these presentations, and especially the recommendations of the working groups, will prove useful to the various linear collider groups in deciding if and when new experimental programs for positron sources should be undertaken.

Clendenin, J.; Nixon, R. [eds.

1997-06-01T23:59:59.000Z

56

Study of Dark Matter inspired cMSSM scenarios at a TeV-class Linear Collider  

E-Print Network [OSTI]

hep- ph/0405253. 4. M. Battaglia, I. Hinchli?e and D. Tovey,level. References 1. M. Battaglia et al. , Eur. Phys. J. CCLASS LINEAR COLLIDER MARCO BATTAGLIA Department of Physics

Battaglia, Marco

2009-01-01T23:59:59.000Z

57

Zeroth-order design report for the next linear collider. Volume 1  

SciTech Connect (OSTI)

This Zeroth Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The design presented here is not fully engineered in any sense, but to be assured that the NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume one covers the following: the introduction; electron source; positron source; NLC damping rings; bunch compressors and prelinac; low-frequency linacs and compressors; main linacs; design and dynamics; and RF systems for main linacs.

Raubenheimer, T.O. [ed.

1996-05-01T23:59:59.000Z

58

Zeroth-order design report for the next linear collider. Volume 2  

SciTech Connect (OSTI)

This Zeroth-Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The ``design`` presented here is not fully engineered in any sense, but to be assured that the NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume II covers the following: collimation systems; IP switch and big bend; final focus; the interaction region; multiple bunch issues; control systems; instrumentation; machine protection systems; NLC reliability considerations; NLC conventional facilities. Also included are four appendices on the following topics: An RF power source upgrade to the NLC; a second interaction region for gamma-gamma, gamma-electron; ground motion: theory and measurement; and beam-based feedback: theory and implementation.

Raubenheimer, T.O. [ed.

1996-05-01T23:59:59.000Z

59

DEPFET active pixel detectors for a future linear $e^+e^-$ collider  

E-Print Network [OSTI]

The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\\mathrm{\\mathbf{\\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\\mathbf{e^+ e^-}$ collider.

Alonso, O; Dieguez, A; Dingfelder, J; Hemperek, T; Kishishita, T; Kleinohl, T; Koch, M; Krueger, H; Lemarenko, M; Luetticke, F; Marinas, C; Schnell, M; Wermes, N; Campbell, A; Ferber, T; Kleinwort, C; Niebuhr, C; Soloviev, Y; Steder, M; Volkenborn, R; Yaschenko, S; Fischer, P; Kreidl, C; Peric, I; Knopf, J; Ritzert, M; Curras, E; Lopez-Virto, A; Moya, D; Vila, I; Boronat, M; Esperante, D; Fuster, J; Garcia Garcia, I; Lacasta, C; Oyanguren, A; Ruiz, P; Timon, G; Vos, M; Gessler, T; Kuehn, W; Lange, S; Muenchow, D; Spruck, B; Frey, A; Geisler, C; Schwenker, B; Wilk, F; Barvich, T; Heck, M; Heindl, S; Lutz, O; Mueller, Th; Pulvermacher, C; Simonis, H.J; Weiler, T; Krausser, T; Lipsky, O; Rummel, S; Schieck, J; Schlueter, T; Ackermann, K; Andricek, L; Chekelian, V; Chobanova, V; Dalseno, J; Kiesling, C; Koffmane, C; Gioi, L.Li; Moll, A; Moser, H.G; Mueller, F; Nedelkovska, E; Ninkovic, J; Petrovics, S; Prothmann, K; Richter, R; Ritter, A; Ritter, M; Simon, F; Vanhoefer, P; Wassatsch, A; Dolezal, Z; Drasal, Z; Kodys, P; Kvasnicka, P; Scheirich, J

2013-01-01T23:59:59.000Z

60

Higgs Boson Search at e+e- and Photon Linear Colliders  

E-Print Network [OSTI]

The various search modes for the Higgs bosons of the Standard Model (SM) and its Minimal Supersymmetric Extension (MSSM) at the International Linear Collider (ILC) will be summarized briefly. In particular, as a unique discovery mode the production of heavy neutral MSSM Higgs bosons for medium values of $\\tan\\beta$ in photon collisions will be presented. Furthermore, $\\tau^+\\tau^-$ fusion into MSSM Higgs bosons in the photon mode will be shown to give access to the mixing parameter $\\tan\\beta$ with a precision of better than 10% for large values of this parameter.

M. M. Muhlleitner

2005-12-19T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders  

SciTech Connect (OSTI)

We consider means to damp the wake-field left behind ultra-relativistic charges. In particular, we focus on a pair of travelling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wake-field left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wake-field on trailing bunches. This method entails detuning the characteristic mode frequencies which make-up the electromagnetic field, damping the wake-field, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wake-field and modes, based on a circuit model, are compared with experimental measurements of the wake-field conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wake-fields in a future linear collider consisting of several thousand of these accelerating structures.

Jones, R.M.; Adolphsen, C.E.; Wang, J.W.; Li, Z.; /SLAC

2006-12-18T23:59:59.000Z

62

Investigation into electron cloud effects in the International Linear Collider positron damping ring  

SciTech Connect (OSTI)

We report modeling results for electron cloud buildup and instability in the International Linear Collider positron damping ring. Updated optics, wiggler magnets, and vacuum chamber designs have recently been developed for the 5 GeV, 3.2-km racetrack layout. An analysis of the synchrotron radiation profile around the ring has been performed, including the effects of diffuse and specular photon scattering on the interior surfaces of the vacuum chamber. The results provide input to the cloud buildup simulations for the various magnetic field regions of the ring. The modeled cloud densities thus obtained are used in the instability threshold calculations. We conclude that the mitigation techniques employed in this model will suffice to allow operation of the damping ring at the design operational specifications

Crittenden, J.A.; Conway, J.; Dugan, G.F.; Palmer, M.A.; Rubin, D.L.; Shanks, J.; Sonnad, K.G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M.A.; Guiducci, S.; Pivi, M.T.F.; Wang, L.; Crittenden, J.A.; Conway, J.; Dugan, G.F.; Palmer, M.A.; Rubin, D.L.; Shanks, J.; Sonnad, K.G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M.A.; Guiducci, S.; Pivi, M.T.F.; Wang, L.

2014-02-28T23:59:59.000Z

63

Measurement of the Higgs Boson Mass with a Linear e+e- Collider  

E-Print Network [OSTI]

The potential of a linear e+e- collider operated at a centre-of-mass energy of 350 GeV is studied for the measurement of the Higgs boson mass. An integrated luminosity of 500 fb-1 is assumed. For Higgs boson masses of 120, 150 and 180 GeV the uncertainty on the Higgs boson mass measurement is estimated to be 40, 65 and 70 MeV, respectively. The effects of beam related systematics, namely a bias in the beam energy measurement, the beam energy spread and the luminosity spectrum due to beamstrahlung, on the precision of the Higgs boson mass measurement are investigated. In order to keep the systematic uncertainty on the Higgs boson mass well below the level of the statistical error, the beam energy measurement must be controlled with a relative precision better than 10-4.

P. Garcia-Abia; W. Lohmann; A. Raspereza

2005-05-30T23:59:59.000Z

64

Non-linear model of particle acceleration at colliding shock flows  

E-Print Network [OSTI]

Powerful stellar winds and supernova explosions with intense energy release in the form of strong shock waves can convert a sizeable part of the kinetic energy release into energetic particles. The starforming regions are argued as a favorable site of energetic particle acceleration and could be efficient sources of nonthermal emission. We present here a non-linear time-dependent model of particle acceleration in the vicinity of two closely approaching fast magnetohydrodynamic (MHD) shocks. Such MHD flows are expected to occur in rich young stellar cluster where a supernova is exploding in the vicinity of a strong stellar wind of a nearby massive star. We find that the spectrum of the high energy particles accelerated at the stage of two closely approaching shocks can be harder than that formed at a forward shock of an isolated supernova remnant. The presented method can be applied to model particle acceleration in a variety of systems with colliding MHD flows.

Bykov, A M; Osipov, S M

2012-01-01T23:59:59.000Z

65

Phenomenology of a leptonic goldstino and invisible Higgs boson decays  

E-Print Network [OSTI]

Non-linearly realized supersymmetry, combined with the Standard Model field content and SU(3)XSU(2)XU(1) gauge invariance, permits local dimension-six operators involving a goldstino, a lepton doublet and a Higgs doublet. These interactions preserve total lepton number if the left-handed goldstino transforms as an antilepton. We discuss the resulting phenomenology, in the simple limit where the new couplings involve only one lepton family, thus conserving also lepton flavour. Both the Z boson and the Higgs boson can decay into a neutrino and a goldstino: the present limits from the invisible Z width and from other observables leave room for the striking possibility of a Higgs boson decaying dominantly, or at least with a sizable branching ratio, via such an invisible mode. We finally comment on the perspectives at hadron and lepton colliders, and on possible extensions of our analysis.

Ignatios Antoniadis; Marc Tuckmantel; Fabio Zwirner

2005-03-23T23:59:59.000Z

66

Interim report on the Global Design Effort Global International Linear Collider (ILC) R&D  

SciTech Connect (OSTI)

The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of the work reported here and will contain all the elements needed to propose the ILC to collaborating governments, including a technical design and implementation plan that are realistic and have been better optimised for performance, cost and risk. We are on track to develop detailed plans for the ILC, such that once results from the Large Hadron Collider (LHC) at CERN establish the main science goals and parameters of the next machine, we will be in good position to make a strong proposal for this new major global project in particle physics. The two overriding issues for the ILC R&D programme are to demonstrate that the technical requirements for the accelerator are achievable with practical technologies, and that the ambitious physics goals can be addressed by realistic ILC detectors. This GDE interim report documents the impressive progress on the accelerator technologies that can make the ILC a reality. It highlights results of the technological demonstrations that are giving the community increased confidence that we will be ready to proceed with an ILC project following the TDR. The companion detector and physics report document likewise demonstrates how detector designs can meet the ambitious and detailed physics goals set out by the ILC Steering Committee. LHC results will likely affect the requirements for the machine design and the detectors, and we are monitoring that very closely, intending to adapt our design as those results become available.

Harrison, M.

2011-04-30T23:59:59.000Z

67

Double Beta Decay, Lepton Flavour Violation and Collider Signatures of Left-Right Symmetric Models with Spontaneous D Parity Breaking  

E-Print Network [OSTI]

We propose a class of left-right symmetric models (LRSMs) with spontaneous D parity breaking, where SU(2)_R breaks at the TeV scale while discrete left-right symmetry breaks around 10^9 GeV. By embedding this framework in a non-supersymmetric SO(10) Grand Unified Theory (GUT) with Pati-Salam symmetry as the highest intermediate breaking step, we obtain g_R / g_L ~ 0.6 between the right- and left-handed gauge couplings at the TeV scale. This leads to a suppression of beyond the Standard Model phenomena induced by the right-handed gauge coupling. Here we focus specifically on the consequences for neutrinoless double beta decay, low energy lepton flavour violation and LHC signatures due to the suppressed right handed currents. Interestingly, the reduced g_R allows us to interpret an excess of events observed recently in the range of 1.9 TeV to 2.4 TeV by the CMS group at the LHC as the signature of a right handed gauge boson in LRSMs with spontaneous D parity breaking. Moreover, the reduced right-handed gauge coupling also strongly suppresses the non-standard contribution of heavy states to the neutrinoless double beta decay rate as well as the amplitude of low energy lepton flavour violating processes. In a dominant type-II Seesaw mechanism of neutrino mass generation, we find that both sets of observables provide stringent and complimentary bounds which make it challenging to observe the scenario at the LHC.

Frank F. Deppisch; Tomas E. Gonzalo; Sudhanwa Patra; Narendra Sahu; Utpal Sarkar

2014-10-23T23:59:59.000Z

68

Optical tuning in the arcs and final focus sections of the Stanford Linear Collider  

SciTech Connect (OSTI)

In this thesis, we present the experimental tuning procedures developed for the Arcs and for the Final Focus Section of the Stanford Linear Collider (SLC). Such tuning is necessary to maximize the luminosity, by minimizing the beam size at the interaction point, and to reduce backgrounds in the experiment. In the final Focus Section, the correction strategy must result from the principles of the optical design, which is based on cancellations between second order aberrations, and on the ability to measure micron-size beams typical of the SLC. In the Arcs, the corrections were designed after the initial commissioning, to make the system more error-tolerant, through a modification in the optical design, and to enable adjustments of the beam phase-space a the injection to the Final Focus System, through a harmonic perturbation technique inspired from circular accelerators. Although the overall optimization of the SLC is not entirely finished, an almost optimal set-up has been achieved for the optics of the Arcs and of the Final Focus Section. Beams with transverse sizes close to the nominal ones, of a few microns, have been obtained at the interaction point. We present and discuss our results and the optical limits to the present performance. 24 refs., 25 figs., 2 tabs.

Bambade, P.S.

1989-03-01T23:59:59.000Z

69

Detectors for Linear Colliders: Physics Requirements and Experimental Conditions (1/4)  

ScienceCinema (OSTI)

How is the anticipated physics program of a future e+e- collider shaping the R&D; for new detectors in collider particle physics ? This presentation will review the main physics requirements and experimental conditions comparing to LHC and LEP. In particular, I shall discuss how e+e- experimentation is expected to change moving from LEP-2 up to multi-TeV energies.

None

2011-10-06T23:59:59.000Z

70

A Highly Granular Silicon-Tungsten Electromagnetic Calorimeter and Top Quark Production at the International Linear Collider  

E-Print Network [OSTI]

This thesis deals with two aspects of the International Linear Collider (ILC) which is a project of a linear electron-positron collider of up to at least 500 GeV center of mass energy. The first aspect is the development of a silicon-tungsten electromagnetic calorimeter (SiW-ECAL) for one of the detectors of the ILC. The concept of this detector is driven by the ILC beam specifications and by the Particle Flow Algorithm (PFA). This requires highly granular calorimeter and very compact one with integrated electronics. To prove the capability of the SiW- ECAL a technological prototype has been built and tested in test beam at DESY. The results are presented here, and show, after the calibration procedure a signal over noise ratio of 10, even in the power pulsing mode. The second aspect is the study of one of the important physics channels of the ILC, the top anti-top quark pairs production. The main goal of this study is to determine the precision that we can expect at the ILC on the top coupling with the W bos...

Rouëné, J

2014-01-01T23:59:59.000Z

71

International Linear Collider Reference Design Report Volume 2: Physics at the ILC  

SciTech Connect (OSTI)

The triumph of 20th century particle physics was the development of the Standard Model and the confirmation of many of its aspects. Experiments determined the particle constituents of ordinary matter, and identified four forces that hold matter together and transform it from one form to another. Particle interactions were found to obey precise laws of relativity and quantum theory. Remarkable features of quantum physics were observed, including the real effects of 'virtual' particles on the visible world. Building on this success, particle physicists are now able to address questions that are even more fundamental, and explore some of the deepest mysteries in science. The scope of these questions is illustrated by this summary from the report Quantum Universe: (1) Are there undiscovered principles of nature; (2) How can we solve the mystery of dark energy; (3) Are there extra dimensions of space; (4) Do all the forces become one; (5) Why are there so many particles; (6) What is dark matter? How can we make it in the laboratory; (7) What are neutrinos telling us; (8) How did the universe begin; and (9) What happened to the antimatter? A worldwide program of particle physics investigations, using multiple approaches, is already underway to explore this compelling scientific landscape. As emphasized in many scientific studies, the International Linear Collider is expected to play a central role in what is likely to be an era of revolutionary advances. Discoveries from the ILC could have breakthrough impact on many of these fundamental questions. Many of the scientific opportunities for the ILC involve the Higgs particle and related new phenomena at Terascale energies. The Standard Model boldly hypothesizes a new form of Terascale energy, called the Higgs field, that permeates the entire universe. Elementary particles acquire mass by interacting with this field. The Higgs field also breaks a fundamental electroweak force into two forces, the electromagnetic and weak forces, which are observed by experiments in very different forms. So far, there is no direct experimental evidence for a Higgs field or the Higgs particle that should accompany it. Furthermore, quantum effects of the type already observed in experiments should destabilize the Higgs boson of the Standard Model, preventing its operation at Terascale energies. The proposed antidotes for this quantum instability mostly involve dramatic phenomena at the Terascale: new forces, a new principle of nature called supersymmetry, or even extra dimensions of space. Thus for particle physicists the Higgs boson is at the center of a much broader program of discovery, taking off from a long list of questions. Is there really a Higgs boson? If not, what are the mechanisms that give mass to particles and break the electroweak force? If there is a Higgs boson, does it differ from the hypothetical Higgs of the Standard Model? Is there more than one Higgs particle? What are the new phenomena that stabilize the Higgs boson at the Terascale? What properties of Higgs boson inform us about these new phenomena? Another major opportunity for the ILC is to shed light on the dark side of the universe. Astrophysical data shows that dark matter dominates over visible matter, and that almost all of this dark matter cannot be composed of known particles. This data, combined with the concordance model of Big Bang cosmology, suggests that dark matter is comprised of new particles that interact weakly with ordinary matter and have Terascale masses. It is truely remarkable that astrophysics and cosmology, completely independently of the particle physics considerations reviewed above, point to new phenomena at the Terascale. If Terascale dark matter exists, experiments at the ILC should be able to produce such particles in the laboratory and study their properties. Another list of questions will then beckon. Do these new particles really have the correct properties to be the dark matter? Do they account for all of the dark matter, or only part of it? What do their properties tell us about the evolut

Aarons, Gerald; Abe, Toshinori; Abernathy, Jason; Ablikim, Medina; Abramowicz, Halina; Adey, David; Adloff, Catherine; Adolphsen, Chris; Afanaciev, Konstantin; Agapov, Ilya; Ahn, Jung-Keun; Aihara, Hiroaki; Akemoto, Mitsuo; del Carmen Alabau, Maria; Albert, Justin; Albrecht, Hartwig; Albrecht, Michael; Alesini, David; Alexander, Gideon; Alexander, Jim; Allison, Wade; /SLAC /Tokyo U. /Victoria U. /Beijing, Inst. High Energy Phys. /Tel Aviv U. /Birmingham U. /Annecy, LAPP /Minsk, High Energy Phys. Ctr. /DESY /Royal Holloway, U. of London /CERN /Pusan Natl. U. /KEK, Tsukuba /Orsay, LAL /Notre Dame U. /Frascati /Cornell U., Phys. Dept. /Oxford U. /Hefei, CUST /Bangalore, Indian Inst. Sci. /Fermilab

2011-11-14T23:59:59.000Z

72

The Vertex Tracker at the e+e- Linear Collider Conceptual Design, Detector R&D and Physics Performances for the Next Generation of Silicon Vertex Detectors  

E-Print Network [OSTI]

The e+e- linear collider physics programme sets highly demanding requirements on the accurate determination of charged particle trajectories close to their production point. A new generation of Vertex Trackers, based on different technologies of high resolution silicon sensors, is being developed to provide the needed performances. These developments are based on the experience with the LEP/SLC vertex detectors and on the results of the R&D programs for the LHC trackers and also define a further program of R&D specific to the linear collider applications. In this paper the present status of the conceptual tracker design, silicon detector R&D and physics studies is discussed.

Marco Battaglia; Massimo Caccia

1999-11-26T23:59:59.000Z

73

A Method for the Precision Mass Measurement of the Stop Quark at the International Linear Collider  

SciTech Connect (OSTI)

Many supersymmetric models predict new particles within the reach of the next generation of colliders. For an understanding of the model structure and the mechanism(s) of symmetry breaking, it is important to know the masses of the new particles precisely. In this article the measurement of the mass of the scalar partner of the top quark (stop) at an e+e- collider is studied. A relatively light stop is motivated by attempts to explain electroweak baryogenesis and can play an important role in dark matter relic density. A method is presented which makes use of cross-section measurements near the pair-production threshold as well as at higher center-of-mass energies. It is shown that this method not only increases the statistical precision, but also greatly reduces the systematic uncertainties, which can be important. Numerical results are presented, based on a realistic event simulation, for two signal selection strategies: using conventional selection cuts, and using an Iterative Discriminant Analysis (IDA). Our studies indicate that a precision of {Delta}m{tilde t}{sub 1} = 0.42 GeV can be achieved, representing a major improvement over previous studies. While the analysis of stops is particularly challenging due to the possibility of stop hadronization, the general procedure could be applied to the mass measurement of other particles as well. We also comment on the potential of the IDA to discover a stop quark in this scenario, and we revisit the accuracy of the theoretical predictions for the neutralino relic density

Freitas, Ayres; /Chicago U. /Argonne /Zurich U.; Milstene, Caroline; /Fermilab /Wayne State U.; Schmitt, Michael; /Northwestern U.; Sopczak, Andre; /Lancaster U.

2008-06-01T23:59:59.000Z

74

Recent Electron-Cloud Simulation Results for the Main Damping Rings of the NLC and the TESLA Linear Colliders  

SciTech Connect (OSTI)

In the beam pipe of the Main Damping Ring (MDR) of the Next Linear Collider (NLC), ionization of residual gases and secondary emission give rise to an electron-cloud which stabilizes to equilibrium after few bunch trains. In this paper, we present recent computer simulation results for the main features of the electron cloud at the NLC and preliminary simulation results for the TESLA main damping rings, obtained with the code POSINST that has been developed at LBNL, and lately in collaboration with SLAC, over the past 7 years. Possible remedies to mitigate the effect are also discussed. We have recently included the possibility to simulate different magnetic field configurations in our code including solenoid, quadrupole, sextupole and wiggler.

Pivi, Mauro T F

2003-05-19T23:59:59.000Z

75

Photon collider Higgs factories  

E-Print Network [OSTI]

The discovery of the Higgs boson (and still nothing else) have triggered appearance of many proposals of Higgs factories for precision measurement of the Higgs properties. Among them there are several projects of photon colliders (PC) without e+e- in addition to PLC based on e+e- linear colliders ILC and CLIC. In this paper, following a brief discussion of Higgs factories physics program I give an overview of photon colliders based on linear colliders ILC and CLIC, and of the recently proposed photon-collider Higgs factories with no e+e- collision option based on recirculation linacs in ring tunnels.

V. I. Telnov

2014-09-19T23:59:59.000Z

76

Measurement of the Top Quark Mass by Dynamical Likelihood Method using the Lepton + Jets Events with the Collider Detector at Fermilab  

SciTech Connect (OSTI)

We have measured the top quark mass with the dynamical likelihood method. The data corresponding to an integrated luminosity of 1.7fb{sup -1} was collected in proton antiproton collisions at a center of mass energy of 1.96 TeV with the CDF detector at Fermilab Tevatron during the period March 2002-March 2007. We select t{bar t} pair production candidates by requiring one high energy lepton and four jets, in which at least one of jets must be tagged as a b-jet. In order to reconstruct the top quark mass, we use the dynamical likelihood method based on maximum likelihood method where a likelihood is defined as the differential cross section multiplied by the transfer function from observed quantities to parton quantities, as a function of the top quark mass and the jet energy scale(JES). With this method, we measure the top quark mass to be 171.6 {+-} 2.0 (stat.+ JES) {+-} 1.3(syst.) = 171.6 {+-} 2.4 GeV/c{sup 2}.

Kubo, Taichi; /Tsukuba U.

2008-02-01T23:59:59.000Z

77

Neutrinos and Collider Physics  

E-Print Network [OSTI]

We review the collider phenomenology of neutrino physics and the synergetic aspects at energy, intensity and cosmic frontiers to test the new physics behind the neutrino mass mechanism. In particular, we focus on seesaw models within the minimal setup as well as with extended gauge and/or Higgs sectors, and on supersymmetric neutrino mass models with seesaw mechanism and with $R$-parity violation. In the simplest Type-I seesaw scenario with sterile neutrinos, we summarize and update the current experimental constraints on the sterile neutrino mass and its mixing with the active neutrinos. We also discuss the future experimental prospects of testing the seesaw mechanism at colliders and in related low-energy searches for rare processes, such as lepton flavor violation and neutrinoless double beta decay. The implications of the discovery of lepton number violation at the LHC for leptogenesis are also studied.

Deppisch, Frank F; Pilaftsis, Apostolos

2015-01-01T23:59:59.000Z

78

Hadron collider physics at UCR  

SciTech Connect (OSTI)

This paper describes the research work in high energy physics by the group at the University of California, Riverside. Work has been divided between hadron collider physics and e{sup +}-e{sup {minus}} collider physics, and theoretical work. The hadron effort has been heavily involved in the startup activities of the D-Zero detector, commissioning and ongoing redesign. The lepton collider work has included work on TPC/2{gamma} at PEP and the OPAL detector at LEP, as well as efforts on hadron machines.

Kernan, A.; Shen, B.C.

1997-07-01T23:59:59.000Z

79

Looking for hints of a reconstructible seesaw model at the Large Hadron Collider  

E-Print Network [OSTI]

We study the production of heavy neutrinos at the Large Hadron Collider (LHC) through the dominant s-channel production mode as well as the vector boson fusion (VBF) process. We consider the TeV scale minimal linear seesaw model containing two heavy singlets with opposite lepton number. This model is fully reconstructible from oscillation data apart from an overall normalization constant which can be constrained from meta-stability of the electroweak vacuum and bounds coming from lepton flavor violation (LFV) searches. Dirac nature of heavy neutrinos in this model implies suppression of the conventional same-sign-dilepton signal at the LHC. We analyze the collider signatures with tri-lepton final state and missing transverse energy as well as VBF type signals which are characterized by two additional forward tagged jets. Our investigation reveals that due to stringent constraints on light-heavy mixing coming from LFV and meta-stability bounds, the model can be explored only for light to moderate mass range of heavy neutrinos. We also note that in case of a positive signal, flavor counting of the final tri-lepton channel can give information about the mass hierarchy of the light neutrinos.

Gulab Bambhaniya; Srubabati Goswami; Subrata Khan; Partha Konar; Tanmoy Mondal

2014-10-21T23:59:59.000Z

80

Measurement of the Inclusive Leptonic Asymmetry in Top-Quark Pairs that Decay to Two Charged Leptons at CDF  

SciTech Connect (OSTI)

We measure the inclusive forward-backward asymmetry of the charged-lepton pseudorapidities from top-quark pairs produced in proton-antiproton collisions, and decaying to final states that contain two charged leptons (electrons or muons), using data collected with the Collider Detector at Fermilab.

Aaltonen, Timo Antero; et al.,

2014-07-23T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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81

Limits on tau lepton flavor violating decays in three charged leptons  

SciTech Connect (OSTI)

A search for the neutrinoless, lepton-flavor violating decay of the {tau} lepton into three charged leptons has been performed using an integrated luminosity of 468 fb{sup -1} collected with the BABAR detector at the PEP-II collider. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (1.8-3.3) x 10{sup -8} at 90% confidence level.

Cervelli, Alberto

2010-04-29T23:59:59.000Z

82

Neutral Higgs-pair production at Linear Colliders within the general 2HDM: quantum effects and triple Higgs boson self-interactions  

E-Print Network [OSTI]

The pairwise production of neutral Higgs bosons is analyzed in the context of the future linear colliders, such as the ILC and CLIC, within the general Two-Higgs-Doublet Model (2HDM). The corresponding cross-sections are computed at the one-loop level in full compliance with the current phenomenological bounds and the stringent theoretical constraints inherent to the consistency of the model. We uncover regions across the 2HDM parameter space, mainly for low tan\\beta near 1 and moderate values of the relevant lambda_5 parameter, wherein the radiative corrections to the Higgs-pair production cross sections can comfortably reach 50% This behavior can be traced back to the enhancement capabilities of the trilinear Higgs self-interactions -- a trademark feature of the 2HDM, with no counterpart in the Minimal Supersymmetric Standard Model. Interestingly enough, the quantum effects are positive for energies around 500 GeV, thereby producing a significant enhancement in the expected number of events precisely around the fiducial startup energy of the ILC. The Higgs-pair production rates can be substantial, typically amounting to a few thousand events per 500 inverse femtobarn of integrated luminosity. In contrast, the corrections are negative in the highest energy range (1 TeV). We also compare the exclusive pairwise production of Higgs bosons with the inclusive gauge boson fusion channels leading to 2H+X finals states, and also with the exclusive triple Higgs boson production. We find that these multiparticle final states can be highly complementary in the overall Higgs bosons search strategy.

David Lopez-Val; Joan Sola

2010-01-08T23:59:59.000Z

83

Muon Collider Task Force Report  

SciTech Connect (OSTI)

Muon Colliders offer a possible long term path to lepton-lepton collisions at center-of-mass energies {radical}s {ge} 1 TeV. In October 2006 the Muon Collider Task Force (MCTF) proposed a program of advanced accelerator R&D aimed at developing the Muon Collider concept. The proposed R&D program was motivated by progress on Muon Collider design in general, and in particular, by new ideas that have emerged on muon cooling channel design. The scope of the proposed MCTF R&D program includes muon collider design studies, helical cooling channel design and simulation, high temperature superconducting solenoid studies, an experimental program using beams to test cooling channel RF cavities and a 6D cooling demonstration channel. The first year of MCTF activities are summarized in this report together with a brief description of the anticipated FY08 R&D activities. In its first year the MCTF has made progress on (1) Muon Collider ring studies, (2) 6D cooling channel design and simulation studies with an emphasis on the HCC scheme, (3) beam preparations for the first HPRF cavity beam test, (4) preparations for an HCC four-coil test, (5) further development of the MANX experiment ideas and studies of the muon beam possibilities at Fermilab, (6) studies of how to integrate RF into an HCC in preparation for a component development program, and (7) HTS conductor and magnet studies to prepare for an evaluation of the prospects for of an HTS high-field solenoid build for a muon cooling channel.

Ankenbrandt, C.; Alexahin, Y.; Balbekov, V.; Barzi, E.; Bhat, C.; Broemmelsiek, D.; Bross, A.; Burov, A.; Drozhdin, A.; Finley, D.; Geer, S.; /Fermilab /Argonne /Brookhaven /Jefferson Lab /LBL, Berkeley /MUONS Inc., Batavia /UCLA /UC, Riverside /Mississippi U.

2007-12-01T23:59:59.000Z

84

Muon Collider Progress: Accelerators  

E-Print Network [OSTI]

A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 \\times 10^34 cm^-2s^-1. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance ("cooling"). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

Michael S. Zisman

2011-09-14T23:59:59.000Z

85

Ion Colliders  

E-Print Network [OSTI]

High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

Fischer, W

2015-01-01T23:59:59.000Z

86

Photon collider at TESLA  

E-Print Network [OSTI]

High energy photon colliders (gamma-gamma, gamma-electron) based on backward Compton scattering of laser light is a very natural addition to e+e- linear colliders. In this report we consider this option for the TESLA project. Recent study has shown that the horizontal emittance in the TESLA damping ring can be further decreased by a factor of four. In this case the gamma-gamma luminosity luminosity in the high energy part of spectrum can reach (1/3)L_{e+e-}. Typical cross sections of interesting processes in gamma-gamma collisions are higher than those in e+e- collisions by about one order of magnitude, so the number of events in gamma-gamma collisions will be more than that in e+e- collisions. Photon colliders can, certainly, give additional information and they are the best for the study of many phenomena. The main question is now the technical feasibility. The key new element in photon colliders is a very powerful laser system. An external optical cavity is a promising approach for the TESLA project. A free electron laser is another option. However, a more straightforward solution is ``an optical storage ring (optical trap)'' with diode pumped solid state laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based at TESLA, its possible parameters and existing problems.

Valery Telnov

2001-03-06T23:59:59.000Z

87

PROSPECTS FOR COLLIDERS AND COLLIDER PHYSICS TO THE 1 PEV ENERGY SCALE  

SciTech Connect (OSTI)

A review is given of the prospects for future colliders and collider physics at the energy frontier. A proof-of-plausibility scenario is presented for maximizing the authors progress in elementary particle physics by extending the energy reach of hadron and lepton colliders as quickly and economically as might be technically and financially feasible. The scenario comprises 5 colliders beyond the LHC--one each of e{sup +}e{sup {minus}} and hadron colliders and three {mu}{sup +}{mu}{sup {minus}} colliders--and is able to hold to the historical rate of progress in the log-energy reach of hadron and lepton colliders, reaching the 1 PeV constituent mass scale by the early 2040's. The technical and fiscal requirements for the feasibility of the scenario are assessed and relevant long-term R and D projects are identified. Considerations of both cost and logistics seem to strongly favor housing most or all of the colliders in the scenario in a new world high energy physics laboratory.

KING,B.J.

2000-05-05T23:59:59.000Z

88

Particle Production Reactions in Laser-Boosted Lepton Collisions  

E-Print Network [OSTI]

The need for ever higher energies in lepton colliders gives rise to the investigation of new accelerator schemes for elementary particle physics experiments. One perceivable way to increase the collision energy would be to combine conventional lepton acceleration with strong laser fields, making use of the momentum boost a charged particle experiences inside a plane electromagnetic wave. As an example for a process taking place in such a laser-boosted collision, Higgs boson creation is studied in detail. We further discuss other possible particle production processes that could be implemented in such a collider scheme and specify the required technical demands.

Sarah J. Müller; Christoph H. Keitel; Carsten Müller

2014-12-28T23:59:59.000Z

89

New Paradigm for Baryon and Lepton Number Violation  

E-Print Network [OSTI]

The possible discovery of proton decay, neutron-antineutron oscillation, neutrinoless beta decay in low energy experiments, and exotic signals related to the violation of the baryon and lepton numbers at collider experiments will change our understanding of the conservation of fundamental symmetries in nature. In this review we discuss the rare processes due to the existence of baryon and lepton number violating interactions. The simplest grand unified theories and the neutrino mass generation mechanisms are discussed. The theories where the baryon and lepton numbers are defined as local gauge symmetries spontaneously broken at the low scale are discussed in detail. The simplest supersymmetric gauge theory which predicts the existence of lepton number violating processes at the low scale is investigated. The main goal of this review is to discuss the main implications of baryon and lepton number violation in physics beyond the Standard Model.

Perez, Pavel Fileviez

2015-01-01T23:59:59.000Z

90

Leptons in Composite MFV  

E-Print Network [OSTI]

We study the lepton sector of composite Higgs models with partial compositeness. The standard anarchic scenario is in conflict with the absence of observable charged lepton flavor violation. This tension can be completely solved in MFV scenarios that require either left-handed or right-handed SM leptons to be equally composite. Constraints on this scenario are weak and the composite lepton partners could be as light as few hundreds GeVs with interesting LHC signatures. The contribution to the muon (g-2) in theories where the Higgs is a pseudo Nambu-Goldstone boson is also discussed.

Michele Redi

2014-07-21T23:59:59.000Z

91

Quark-lepton symmetric model at the LHC  

E-Print Network [OSTI]

We investigate the quark-lepton symmetric model of Foot and Lew in the context of the Large Hadron Collider (LHC). In this `bottom-up' extension to the Standard Model, quark-lepton symmetry is achieved by introducing a gauged `leptonic colour' symmetry which is spontaneously broken above the electroweak scale. If this breaking occurs at the TeV scale, then we expect new physics to be discovered at the LHC. We examine three areas of interest: the Z$'$ heavy neutral gauge boson, charge $\\pm1/2$ exotic leptons, and a colour triplet scalar diquark. We find that the LHC has already explored and/or will explore new parameter space for these particles over the course of its lifetime.

Jackson D. Clarke; Robert Foot; Raymond R. Volkas

2012-02-04T23:59:59.000Z

92

LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS  

E-Print Network [OSTI]

LASER-PLASMA-ACCELERATOR-BASED ?? COLLIDERS ? C. B.linear col- lider based on laser-plasma-accelerators arediscussed, and a laser-plasma-accelerator-based gamma-

Schroeder, C. B.

2010-01-01T23:59:59.000Z

93

LASER-PLASMA-ACCELERATOR-BASED COLLIDERS C. B. Schroeder  

E-Print Network [OSTI]

LASER-PLASMA-ACCELERATOR-BASED COLLIDERS C. B. Schroeder , E. Esarey, Cs. T´oth, C. G. R. Geddes-generation linear col- lider based on laser-plasma-accelerators are discussed, and a laser-plasma-accelerator gamma-gamma () collider is considered. An example of the parameters for a 0.5 TeV laser-plasma-accelerator collider

Geddes, Cameron Guy Robinson

94

Little Flavor: Heavy Leptons, Z' and Higgs Phenomenology  

E-Print Network [OSTI]

The Little Flavor model is a close cousin of the Little Higgs theory which aims to generate flavor structure around TeV scale. While the original Little Flavor only included the quark sector, here we build the lepton part of the Little Flavor model and explore its phenomenology. The model produces the neutrino mixing matrix and Majorana masses of the Standard Model neutrinos through coupling to heavy lepton partners and Little Higgses. We combine the usual right-handed seesaw mechanism with global symmetry protection to suppress the Standard Model neutrino masses, and identify the TeV partners of leptons as right-handed Majorana neutrinos. The lepton masses and mixing matrix are calculated perturbatively in the theory. The TeV new gauge bosons have suppressed decay width in dilepton channels. Even assuming the Standard Model couplings, the branching ratios to normal dilepton channels are largely reduced in the model, to evade the bound from current $Z'$ search. It also opens up the new search channels for exotic gauge bosons, especially Z' -> E_{t missing} + multi L. The multiple lepton partners will create new chain decay signals in flavor related processes in colliders, which also give rise to flavor anomalies. The lepton flavor violation process can be highly suppressed in charged lepton sector and happens only through neutrinos.

Sichun Sun

2014-12-01T23:59:59.000Z

95

Exotic in Leptonic Machines  

E-Print Network [OSTI]

Selected topics of exotics in leptonic machines are presented, including recent discovery of abnormal structures around the ppbar threshold and new information of the XYZ (charmonium-like) states.

Kai Zhu

2014-08-07T23:59:59.000Z

96

Survey of lepton number violation via effective operators  

SciTech Connect (OSTI)

We survey 129 lepton number violating effective operators, consistent with the minimal standard model gauge group and particle content, of mass dimension up to and including 11. Upon requiring that each one radiatively generates the observed neutrino masses, we extract an associated characteristic cutoff energy scale which we use to calculate other observable manifestations of these operators for a number of current and future experimental probes, concentrating on lepton number violating phenomena. These include searches for neutrinoless double-beta decay and rare meson, lepton, and gauge boson decays. We also consider searches at hadron/lepton collider facilities in anticipation of the CERN LHC and the future ILC. We find that some operators are already disfavored by current data, while more are ripe to be probed by next-generation experiments. We also find that our current understanding of lepton mixing disfavors a subset of higher dimensional operators. While neutrinoless double-beta decay is the most promising signature of lepton number violation for the majority of operators, a handful is best probed by other means. We argue that a combination of constraints from various independent experimental sources will help to pinpoint the ''correct'' model of neutrino mass, or at least aid in narrowing down the set of possibilities.

Gouvea, Andre de; Jenkins, James [Northwestern University, Department of Physics and Astronomy, 2145 Sheridan Road, Evanston, Illinois 60208 (United States)

2008-01-01T23:59:59.000Z

97

Conventional power sources for colliders  

SciTech Connect (OSTI)

At SLAC we are developing high peak-power klystrons to explore the limits of use of conventional power sources in future linear colliders. In an experimental tube we have achieved 150 MW at 1 ..mu..sec pulse width at 2856 MHz. In production tubes for SLAC Linear Collider (SLC) we routinely achieve 67 MW at 3.5 ..mu..sec pulse width and 180 pps. Over 200 of the klystrons are in routine operation in SLC. An experimental klystron at 8.568 GHz is presently under construction with a design objective of 30 MW at 1 ..mu..sec. A program is starting on the relativistic klystron whose performance will be analyzed in the exploration of the limits of klystrons at very short pulse widths.

Allen, M.A.

1987-07-01T23:59:59.000Z

98

The Large Hadron Electron Collider Project  

E-Print Network [OSTI]

A Conceptual Design Report (CDR) for the Large Hadron Electron Collider, the LHeC, is being prepared, to which an introduction was given for the plenary panel discussion on the future of deep inelastic scattering held at DIS09. This is briefly summarised here. The CDR will comprise designs of the ep/eA collider, based on ring and linear electron accelerators, of the interaction region, designed for simultaneous $ep$ and $pp$ operation, of a new, modular detector, and it will present basics on the physics motivation for a high luminous Tera scale electron-nucleon collider as a complement to the LHC.

Max Klein

2009-08-20T23:59:59.000Z

99

Gamma-Gamma Colliders  

E-Print Network [OSTI]

a gamma collider, we need to discuss the laser optics in thegamma collider will be given later, coupled with some discussions of the requisite opticsoptics and an adequate laser for Compton conversion. With this approach, the luminosity for the gamma-

Kim, K.-J.

2008-01-01T23:59:59.000Z

100

TESLA*HERA Based gamma-p and gamma-A Colliders  

E-Print Network [OSTI]

Main parameters and physics search potential of gamma-p and gamma-A colliders, which will be available due to constructing the TESLA linear electron-positron collider tangentially to the HERA proton ring, are discussed.

A. K. Ciftci; S. Sultansoy; O. Yavas

2000-07-05T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Neutrino and it's lepton  

E-Print Network [OSTI]

In this paper I cite p.p. 100-117 of book G. Quznetsov, Probabilistic Treatment of Gauge Theories, in series Contemporary Fundamental Physics,ed. V. Dvoeglazov, Nova Sci. Publ., NY (2007). There I research a bound between neutrino and it's lepton.

G. Quznetsov

2008-11-10T23:59:59.000Z

102

Challenges for highest energy circular colliders  

E-Print Network [OSTI]

A new tunnel of 80–100 km circumference could host a 100 TeV centre-of-mass energy-frontier proton collider (FCC-hh/VHE-LHC), with a circular lepton collider (FCCee/TLEP) as potential intermediate step, and a leptonhadron collider (FCC-he) as additional option. FCC-ee, operating at four different energies for precision physics of the Z, W, and Higgs boson and the top quark, represents a significant push in terms of technology and design parameters. Pertinent R&D efforts include the RF system, topup injection scheme, optics design for arcs and final focus, effects of beamstrahlung, beam polarization, energy calibration, and power consumption. FCC-hh faces other challenges, such as high-field magnet design, machine protection and effective handling of large synchrotron radiation power in a superconducting machine. All these issues are being addressed by a global FCC collaboration. A parallel design study in China prepares for a similar, but smaller collider, called CepC/SppC.

Benedikt, M; Wenninger, J; Zimmermann, F

2014-01-01T23:59:59.000Z

103

Measurement of the inclusive leptonic asymmetry in top-quark pairs that decay to two charged leptons at CDF  

E-Print Network [OSTI]

We measure the inclusive forward-backward asymmetry of the charged-lepton pseudorapidities from top-quark pairs produced in proton-antiproton collisions, and decaying to final states that contain two charged leptons (electrons or muons), using data collected with the Collider Detector at Fermilab. With an integrated luminosity of 9.1 $\\rm{fb}^{-1}$, the leptonic forward-backward asymmetry, $A_{\\text{FB}}^{\\ell}$, is measured to be $0.072 \\pm 0.060$ and the leptonic pair forward-backward asymmetry, $A_{\\text{FB}}^{\\ell\\ell}$, is measured to be $0.076 \\pm 0.082$, compared with the standard model predictions of $A_{\\text{FB}}^{\\ell} = 0.038 \\pm 0.003$ and $A_{\\text{FB}}^{\\ell\\ell} = 0.048 \\pm 0.004$, respectively. Additionally, we combine the $A_{\\text{FB}}^{\\ell}$ result with a previous determination from a final state with a single lepton and hadronic jets and obtain $A_{\\text{FB}}^{\\ell} = 0.090^{+0.028}_{-0.026}$.

CDF Collaboration; T. Aaltonen; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; J. A. Appel; T. Arisawa; A. Artikov; J. Asaadi; W. Ashmanskas; B. Auerbach; A. Aurisano; F. Azfar; W. Badgett; T. Bae; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Barria; P. Bartos; M. Bauce; F. Bedeschi; S. Behari; G. Bellettini; J. Bellinger; D. Benjamin; A. Beretvas; A. Bhatti; K. R. Bland; B. Blumenfeld; A. Bocci; A. Bodek; D. Bortoletto; J. Boudreau; A. Boveia; L. Brigliadori; C. Bromberg; E. Brucken; J. Budagov; H. S. Budd; K. Burkett; G. Busetto; P. Bussey; P. Butti; A. Buzatu; A. Calamba; S. Camarda; M. Campanelli; F. Canelli; B. Carls; D. Carlsmith; R. Carosi; S. Carrillo; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; V. Cavaliere; M. Cavalli-Sforza; A. Cerri; L. Cerrito; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; K. Cho; D. Chokheli; A. Clark; C. Clarke; M. E. Convery; J. Conway; M. Corbo; M. Cordelli; C. A. Cox; D. J. Cox; M. Cremonesi; D. Cruz; J. Cuevas; R. Culbertson; N. d'Ascenzo; M. Datta; P. de Barbaro; L. Demortier; L. Marchese; M. Deninno; F. Devoto; M. D'Errico; A. Di Canto; B. Di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; M. Dorigo; A. Driutti; K. Ebina; R. Edgar; A. Elagin; R. Erbacher; S. Errede; B. Esham; S. Farrington; J. P. Fernández Ramos; R. Field; G. Flanagan; R. Forrest; M. Franklin; J. C. Freeman; H. Frisch; Y. Funakoshi; C. Galloni; A. F. Garfinkel; P. Garosi; H. Gerberich; E. Gerchtein; S. Giagu; V. Giakoumopoulou; K. Gibson; C. M. Ginsburg; N. Giokaris; P. Giromini; G. Giurgiu; V. Glagolev; D. Glenzinski; M. Gold; D. Goldin; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González López; I. Gorelov; A. T. Goshaw; K. Goulianos; E. Gramellini; S. Grinstein; C. Grosso-Pilcher; R. C. Group; J. Guimaraes da Costa; S. R. Hahn; J. Y. Han; F. Happacher; K. Hara; M. Hare; R. F. Harr; T. Harrington-Taber; K. Hatakeyama; C. Hays; J. Heinrich; M. Herndon; A. Hocker; Z. Hong; W. Hopkins; S. Hou; R. E. Hughes; U. Husemann; M. Hussein; J. Huston; G. Introzzi; M. Iori; A. Ivanov; E. James; D. Jang; B. Jayatilaka; E. J. Jeon; S. Jindariani; M. Jones; K. K. Joo; S. Y. Jun; T. R. Junk; M. Kambeitz; T. Kamon; P. E. Karchin; A. Kasmi; Y. Kato; W. Ketchum; J. Keung; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; Y. J. Kim; N. Kimura; M. Kirby; K. Knoepfel; K. Kondo; D. J. Kong; J. Konigsberg; A. V. Kotwal; M. Kreps; J. Kroll; M. Kruse; T. Kuhr; M. Kurata; A. T. Laasanen; S. Lammel; M. Lancaster; K. Lannon; G. Latino; H. S. Lee; J. S. Lee; S. Leo; S. Leone; J. D. Lewis; A. Limosani; E. Lipeles; A. Lister; H. Liu; Q. Liu; T. Liu; S. Lockwitz; A. Loginov; A. Lucà; D. Lucchesi; J. Lueck; P. Lujan; P. Lukens; G. Lungu; J. Lys; R. Lysak; R. Madrak; P. Maestro; S. Malik; G. Manca; A. Manousakis-Katsikakis; F. Margaroli; P. Marino; M. Martínez; K. Matera; M. E. Mattson; A. Mazzacane; P. Mazzanti; R. McNulty; A. Mehta; P. Mehtala; C. Mesropian; T. Miao; D. Mietlicki; A. Mitra; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. J. Morello; A. Mukherjee; Th. Muller; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; J. Naganoma; I. Nakano; A. Napier; J. Nett; C. Neu; T. Nigmanov; L. Nodulman; S. Y. Noh; O. Norniella; L. Oakes; S. H. Oh; Y. D. Oh; I. Oksuzian; T. Okusawa; R. Orava; L. Ortolan; C. Pagliarone; E. Palencia; P. Palni; V. Papadimitriou; W. Parker; G. Pauletta; M. Paulini; C. Paus; T. J. Phillips; G. Piacentino; E. Pianori; J. Pilot; K. Pitts; C. Plager; L. Pondrom; S. Poprocki; K. Potamianos; F. Prokoshin; A. Pranko; F. Ptohos; G. Punzi; N. Ranjan; I. Redondo Fernández; P. Renton; M. Rescigno; F. Rimondi; L. Ristori; A. Robson; T. Rodriguez; S. Rolli; M. Ronzani; R. Roser; J. L. Rosner; F. Ruffini; A. Ruiz; J. Russ; V. Rusu; W. K. Sakumoto; Y. Sakurai; L. Santi; K. Sato; V. Saveliev; A. Savoy-Navarro; P. Schlabach; E. E. Schmidt; T. Schwarz; L. Scodellaro; F. Scuri; S. Seidel; Y. Seiya; A. Semenov; F. Sforza; S. Z. Shalhout; T. Shears; P. F. Shepard; M. Shimojima; M. Shochet; I. Shreyber-Tecker; A. Simonenko; K. Sliwa; J. R. Smith; F. D. Snider; V. Sorin; H. Song; M. Stancari; R. St. Denis; D. Stentz; J. Strologas; Y. Sudo; A. Sukhanov; I. Suslov; K. Takemasa; Y. Takeuchi; J. Tang; M. Tecchio; P. K. Teng; J. Thom; E. Thomson; V. Thukral; D. Toback; S. Tokar; K. Tollefson; T. Tomura; D. Tonelli; S. Torre; D. Torretta; P. Totaro; M. Trovato; F. Ukegawa; S. Uozumi; F. Vázquez; G. Velev; C. Vellidis; C. Vernieri; M. Vidal; R. Vilar; J. Vizán; M. Vogel; G. Volpi; P. Wagner; R. Wallny; S. M. Wang; D. Waters; W. C. Wester III; D. Whiteson; A. B. Wicklund; S. Wilbur; H. H. Williams; J. S. Wilson; P. Wilson; B. L. Winer; P. Wittich; S. Wolbers; H. Wolfe; T. Wright; X. Wu; Z. Wu; K. Yamamoto; D. Yamato; T. Yang; U. K. Yang; Y. C. Yang; W. -M. Yao; G. P. Yeh; K. Yi; J. Yoh; K. Yorita; T. Yoshida; G. B. Yu

2014-04-14T23:59:59.000Z

104

Inclusive Higgs Boson Searches in Four-Lepton Final States at the LHC  

E-Print Network [OSTI]

The inclusive search for the Standard Model Higgs boson in four-lepton final states with the ATLAS and CMS detectors at the LHC pp collider is presented. The discussion focusses on the H-> ZZ^(*)->4l+X decay mode for a Higgs boson in the mass range 120 ~Higgs boson properties is also given.

Evelyne Delmeire

2007-05-15T23:59:59.000Z

105

Linear Collider Calorimeter Testbeam Study Group Report  

E-Print Network [OSTI]

segmentation to distinguish energy deposits from charged and neutral hadrons, associating the energy clusters#cient single particle shower data at a wide range of energies for EFA development to construct shower librari, jet energy resolutions need to be at the level of 30%/ # E that is capable of distinguishing W and Z

Yu, Jaehoon

106

Linear Collider Calorimeter Testbeam Study Group Report  

E-Print Network [OSTI]

segmentation to distinguish energy deposits from charged and neutral hadrons, associating the energy clusters: · Sufficient single particle shower data at a wide range of energies for EFA development to construct shower , jet energy resolutions need to be at the level of 30%/ E that is capable of distinguishing W and Z

Yu, Jaehoon

107

International linear collider reference design report  

E-Print Network [OSTI]

m Shaft with Underground Cavern, Service and Beam Tunnels (Hall, showing BDS Service Cavern Arrangement 4.2-6 4.4-1 AirConstruction Water Halls Caverns e ? ML Shaft Base Caverns

Aarons, G.

2008-01-01T23:59:59.000Z

108

International linear collider reference design report  

E-Print Network [OSTI]

transformers located along the Service Tunnel tap-o? the MV distribution system to provide power to the LV systems and components.

Aarons, G.

2008-01-01T23:59:59.000Z

109

Radiative Leptonic B Decays  

SciTech Connect (OSTI)

We present the results of a search for B{sup +} meson decays into {gamma}{ell}{sup +}{nu}{sub {ell}}, where {ell} = e,{mu}. We use a sample of 232 million B{bar B} meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B factory. We measure a partial branching fraction {Delta}{beta} in a restricted region of phase space that reduces the effect of theoretical uncertainties, requiring the lepton energy to be in the range 1.875 and 2.850 GeV, the photon energy to be in the range 0.45 and 2.35 GeV, and the cosine of the angle between the lepton and photon momenta to be less than -0.36, with all quantities computed in the {Upsilon}(4S) center-of-mass frame. We find {Delta}{Beta}(B{sup +} {yields} {gamma}{ell}{sup +}{nu}{sub {ell}}) = (-0.3{sub 1.5}{sup +1.3}(statistical){sub -0.6}{sup +0.6}(systematic) {+-} 0.1(theoretical)) x 10{sup -6}, under the assumption of lepton universality. Interpreted as a 90% confidence-level Bayesian upper limit, the result corresponds to 1.7 x 10{sup -6} for a prior at in amplitude, and 2.3 x 10{sup -6} for a prior at in branching fraction.

Chen, Edward Tann; /Caltech; ,

2008-10-06T23:59:59.000Z

110

Twistor Spinoffs for Collider Physics  

SciTech Connect (OSTI)

Finding the adding up of Feynman diagrams tedious? Hidden symmetries found in the sums of diagrams suggest there is a better way to predict the results of particle collisions - in the past two years, spin-offs of a new theory, known as the Twistor String Theory, have led to the development of efficient alternatives to Feynman diagrams which can be useful for work at the Tevatron, the LHC and for future research at the International Linear Collider. Come see what this 'twistor' is all about!

Dixon, Lance

2005-12-19T23:59:59.000Z

111

Lepton textures and neutrino oscillations  

E-Print Network [OSTI]

Systematic analyses of the textures arising in lepton mass matrices have been carried out using unitary transformations and condition of naturalness for the Dirac and Majorana neutrino possibilities. It is observed that the recent three neutrino oscillation data together with the effective mass in neutrinoless double beta decay provide vital clues in predicting the general structures of these lepton mass matrices.

Verma, Rohit

2014-01-01T23:59:59.000Z

112

Signatures for Right-Handed Neutrinos at the Large Hadron Collider  

SciTech Connect (OSTI)

We explore possible signatures for right-handed neutrinos in a TeV scale B-L extension of the standard model at the Large Hadron Collider. The studied four lepton signal has a tiny standard model background. We find the signal experimentally accessible at the LHC for the considered parameter regions.

Huitu, Katri; Rai, Santosh Kumar [Department of Physics, University of Helsinki and Helsinki Institute of Physics, P.O. Box 64, FIN-00014 University of Helsinki (Finland); Khalil, Shaaban [Centre for Theoretical Physics, British University in Egypt, El Sherouk City, Postal No, 11837, P.O. Box 43 (Egypt); Department of Mathematics, Ain Shams University, Faculty of Science, Cairo, 11566 (Egypt); Okada, Hiroshi [Centre for Theoretical Physics, British University in Egypt, El Sherouk City, Postal No, 11837, P.O. Box 43 (Egypt)

2008-10-31T23:59:59.000Z

113

SPADs for Vertex Tracker detectors in Future Colliders  

E-Print Network [OSTI]

Physics aims at the future linear colliders impose such stringent requirements on detector systems that exceed those met by any previous technology. Amongst other novel technologies, SPADs (Single Photon Avalanche Diodes) detectors are being developed to track high energy particles at ILC (International Linear Collider) and CLIC (Compact LInear Collider). These sensors offer outstanding qualities, such as an extraordinary high sensitivity, ultra-fast response time and virtually infinite gain, in addition to compatibility with standard CMOS technologies. As a result, SPAD detectors enable the direct conversion of a single particle event onto a CMOS digital signal in the sub-nanosecond time scale, which leads to the possibility of single BX (bunch crossing) resolution at some particle colliders. However, SPAD detectors suffer from two main problems, namely the noise pulses generated by the sensor and the low fill-factor. The noise pulses worsen the detector occupancy, while the low fill-factor reduces the detec...

Vilella, E; Vila, A; Dieguez, A

2015-01-01T23:59:59.000Z

114

A Search for Neutrinoless Tau Decays to Three Leptons  

SciTech Connect (OSTI)

Using approximately 350 million {tau}{sup +}{tau}{sup -} pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction {Beta}({tau} {yields} {ell}{ell}{ell}) in the range (4-8) x 10{sup -8}.

Kolb, Jeffrey A.; /Oregon U. /SLAC

2008-09-24T23:59:59.000Z

115

Summary of Lepton Photon 2011  

SciTech Connect (OSTI)

In this lecture, I summarize developments presented at the Lepton Photon 2011 conference and give my perspective on the current situation in high-energy physics. I am grateful to the organizers of Lepton Photon 2011 for providing us a very pleasant and simulating week in Mumbai. This year's Lepton Photon conference has covered the full range of subjects that fall within the scope of high-energy physics, including connections to cosmology, nuclear physics, and atomic physics. The experiments that were discussed detect particles ranging in energy from radio frequencies to EeV.

Peskin, Michael E.; /SLAC

2012-03-14T23:59:59.000Z

116

Applying Effective Theories to Collider Phenomenology  

E-Print Network [OSTI]

Theories to Collider Phenomenology by Grigol GagikovichTheories to Collider Phenomenology Copyright 2010 by GrigolTheories to Collider Phenomenology by Grigol Gagikovich

Ovanesyan, Grigol

2010-01-01T23:59:59.000Z

117

E1 Working Group Summary: Neutrino Factories and Muon Colliders  

E-Print Network [OSTI]

We are in the middle of a time of exciting discovery, namely that neutrinos have mass and oscillate. In order to take the next steps to understand this potential window onto what well might be the mechanism that links the quarks and leptons, we need both new neutrino beams and new detectors. The new beamlines can and should also provide new laboratories for doing charged lepton flavor physics, and the new detectors can and should also provide laboratories for doing other physics like proton decay, supernovae searches, etc. The new neutrino beams serve as milestones along the way to a muon collider, which can answer questions in yet another sector of particle physics, namely the Higgs sector or ultimately the energy frontier. In this report we discuss the current status of neutrino oscillation physics, what other oscillation measurements are needed to fully explore the phenomenon, and finally, what other new physics can be explored as a result of building of these facilities.

D. Harris

2001-11-02T23:59:59.000Z

118

Leptonic B Decays at BaBar  

SciTech Connect (OSTI)

The authors will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)} {nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be payed in order to perform a model independent analysis. A B-Factory provides an unique environment where to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.

Monorchio, Diego; /INFN, Naples /Naples U.

2011-09-13T23:59:59.000Z

119

Diffraction at collider energies  

SciTech Connect (OSTI)

Lessons with ``soft`` hadron physics to explain (a) feasibility to observe and to investigate color transparency, color opacity effects at colliders; (b) significant probability and specific features of hard diffractive processes; (c) feasibility to investigate components of parton wave functions of hadrons with minimal number of constituents. This new physics would be more important with increase of collision energy.

Frankfurt, L.L.

1992-12-31T23:59:59.000Z

120

Diffraction at collider energies  

SciTech Connect (OSTI)

Lessons with soft'' hadron physics to explain (a) feasibility to observe and to investigate color transparency, color opacity effects at colliders; (b) significant probability and specific features of hard diffractive processes; (c) feasibility to investigate components of parton wave functions of hadrons with minimal number of constituents. This new physics would be more important with increase of collision energy.

Frankfurt, L.L.

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Future Accelerators, Muon Colliders, and Neutrino Factories  

SciTech Connect (OSTI)

Particle physics is driven by five great topics. Neutrino oscillations and masses are now at the fore. The standard model with extensions to supersymmetry and a Higgs to generate mass explains much of the field. The origins of CP violation are not understood. The possibility of extra dimensions has raised tantalizing new questions. A fifth topic lurking in the background is the possibility of something totally different. Many of the questions raised by these topics require powerful new accelerators. It is not an overstatement to say that for some of the issues, the accelerator is almost the experiment. Indeed some of the questions require machines beyond our present capability. As this volume attests, there are parts of the particle physics program that have been significantly advanced without the use of accelerators such as the subject of neutrino oscillations and many aspects of the particle-cosmology interface. At this stage in the development of physics, both approaches are needed and important. This chapter first reviews the status of the great accelerator facilities now in operation or coming on within the decade. Next, midrange possibilities are discussed including linear colliders with the adjunct possibility of gamma-gamma colliders, muon colliders, with precursor neutrino factories, and very large hadron colliders. Finally visionary possibilities are considered including plasma and laser accelerators.

Richard A Carrigan, Jr.

2001-12-19T23:59:59.000Z

122

Addendum to Distinguishing Spins in Decay Chains at the Large Hadron Collider.  

E-Print Network [OSTI]

ar X iv :h ep -p h/ 06 06 21 2v 1 2 0 Ju n 20 06 Preprint typeset in JHEP style - PAPER VERSION Cavendish–HEP–06/15 Addendum to “Distinguishing Spins in Decay Chains at the Large Hadron Collider”? Christiana Athanasiou1, Christopher G. Lester2... mass distributions of the three observable two-body combinations: dileptons (mll), quark- or antiquark-jet plus positive lepton (mjl+), and jet plus negative lepton (mjl?).1 If P (m|S) represents the normalized probability distribution of any one...

Athanasiou, Christiana; Lester, Christopher G; Smillie, Jennifer M; Webber, Bryan R

123

Higgs Boson Searches at Hadron Colliders (1/4)  

SciTech Connect (OSTI)

In these Academic Training lectures, the phenomenology of Higgs bosons and search strategies at hadron colliders are discussed. After a brief introduction on Higgs bosons in the Standard Model and a discussion of present direct and indirect constraints on its mass the status of the theoretical cross section calculations for Higgs boson production at hadron colliders is reviewed. In the following lectures important experimental issues relevant for Higgs boson searches (trigger, measurements of leptons, jets and missing transverse energy) are presented. This is followed by a detailed discussion of the discovery potential for the Standard Model Higgs boson for both the Tevatron and the LHC experiments. In addition, various scenarios beyond the Standard Model, primarily the MSSM, are considered. Finally, the potential and strategies to measured Higgs boson parameters and the investigation of alternative symmetry breaking scenarios are addressed.

None

2010-06-21T23:59:59.000Z

124

Higgs Boson Searches at Hadron Colliders (1/4)  

ScienceCinema (OSTI)

In these Academic Training lectures, the phenomenology of Higgs bosons and search strategies at hadron colliders are discussed. After a brief introduction on Higgs bosons in the Standard Model and a discussion of present direct and indirect constraints on its mass the status of the theoretical cross section calculations for Higgs boson production at hadron colliders is reviewed. In the following lectures important experimental issues relevant for Higgs boson searches (trigger, measurements of leptons, jets and missing transverse energy) are presented. This is followed by a detailed discussion of the discovery potential for the Standard Model Higgs boson for both the Tevatron and the LHC experiments. In addition, various scenarios beyond the Standard Model, primarily the MSSM, are considered. Finally, the potential and strategies to measured Higgs boson parameters and the investigation of alternative symmetry breaking scenarios are addressed.

None

2011-10-06T23:59:59.000Z

125

Search for neutrinoless decays of the ? lepton  

E-Print Network [OSTI]

We have searched for neutrinoless ? decays into three charged particles. Evidence of such decays would demonstrate nonconservation of lepton flavor and, in some cases, lepton number. We see no signal for any such neutrinoless ? decays and set upper...

Baringer, Philip S.

1990-02-01T23:59:59.000Z

126

Discovering Higgs boson pair production through rare final states at a 100 TeV collider  

E-Print Network [OSTI]

We consider Higgs boson pair production at a future proton collider with centre-of-mass energy of 100 TeV, focusing on rare final states that include a bottom-anti-bottom quark pair and multiple isolated leptons: $hh \\rightarrow (b\\bar{b}) + n \\ell + X$, $n = \\{2,4\\}$, $X = \\{ E_T^\\mathrm{miss}, \\gamma, -\\}$. We construct experimental search strategies for observing the process through these channels and make suggestions on the desired requirements for the detector design of the future collider.

Papaefstathiou, Andreas

2015-01-01T23:59:59.000Z

127

N/Z dependence of balance energy throughout the colliding geometries  

E-Print Network [OSTI]

We study the N/Z dependence of balance energy throughout the mass range for colliding geometry varying from central to peripheral ones. Our results indicate that balance energy decreases linearly with increase in N/Z ratio for all the masses throughout the colliding geometry range. Also, the N/Z dependence of balance energy is sensitive to symmetry energy.

Sakshi Gautam; Rajeev K. Puri

2011-07-28T23:59:59.000Z

128

Colliding neutrino beams  

E-Print Network [OSTI]

From several neutrino oscillation experiments, we understand now that neutrinos have mass. However, we really don't know what mechanism is responsible for producing this neutrino mass. Current or planned neutrino experiments utilize neutrino beams and long-baseline detectors to explore flavor mixing but do not address the question of the origin of neutrino mass. In order to answer that question, neutrino interactions need to be explored at much higher energies. This paper outlines a program to explore neutrinos and their interactions with various particles through a series of experiments involving colliding neutrino beams.

Reinhard Schwienhorst

2007-11-08T23:59:59.000Z

129

Colliding Nuclei at High Energy  

ScienceCinema (OSTI)

Physicist Peter Steinberg explains what happens when atomic nucleii travelling at close to the speed of light smash together in Brookhaven Lab's Relativistic Heavy Ion Collider (RHIC).

Brookhaven Lab

2010-01-08T23:59:59.000Z

130

Natural fourth generation of leptons  

E-Print Network [OSTI]

We consider implications of a fourth generation of leptons, allowing for the most general mass patterns for the fourth generation neutrino. We determine the constraints due to the precision electroweak measurements and outline the signatures to search for at the LHC experiments. As a concrete framework to apply these results we consider the minimal walking technicolor (MWTC) model where the matter content, regarding the electroweak quantum numbers, corresponds to a fourth generation.

Oleg Antipin; Matti Heikinheimo; Kimmo Tuominen

2009-09-14T23:59:59.000Z

131

Results from hadron colliders  

SciTech Connect (OSTI)

The present status of hadron collider physics is reviewed. The total cross section for {bar p} + p has been measured at 1.8 TeV: {sigma}{sub tot} = 72.1 {plus minus} 3.3 mb. New data confirm the UA2 observation of W/Z {yields} {bar q}q. Precision measurements of M{sub W} by UA2 and CDF give an average value M{sub W} = 80.13 {plus minus} 0.30 GeV/c{sup 2}. When combined with measurements of M{sub Z} from LEP and SLC this number gives sin{sup 2}{theta}{sub W} = 0.227 {plus minus} 0.006, or m{sub top} = 130{sub {minus}60}{sup +40} GeV/c{sup 2} from the EWK radiative correction term {Delta}r. Evidence for hadron colliders as practical sources of b quarks has been strengthened, while searches for t quarks have pushed the mass above M{sub W}: m{sub top} > 89 GeV/c{sup 2} 95% cl (CDF Preliminary). Searches beyond the standard model based on the missing E{sub T} signature have not yet produced any positive results. Future prospects for the discovery of the top quark in the range m{sub top} < 200 GeV/c{sup 2} look promising. 80 refs., 35 figs., 7 tabs.

Pondrom, L.G. (Wisconsin Univ., Madison, WI (USA))

1990-12-14T23:59:59.000Z

132

High Energy Colliders as Tools to Understand the Early Universe  

SciTech Connect (OSTI)

Cosmological observations have reached a new era of precision, and reveal many interesting and puzzling features of the Universe. I will briefly review two of the most exciting mysteries: the nature of the dark components of the Universe, and the origin of the asymmetry between matter and anti-matter. I will argue that our best hope of unraveling these questions will need to combine information from the heavens with measurements in the lab at high energy particle accelerators. The end of run II of the Tevatron, the up-coming Large Hadron Collider and proposed International Linear Collider all have great potential to help us answer these questions in the near future.

Tait, Tim (ANL) [ANL

2008-08-16T23:59:59.000Z

133

Lepton Universality Test in Upsilon(1S) Decays at BaBar  

SciTech Connect (OSTI)

Using a sample of 122 million {Upsilon}(3S) decays collected with the BABAR detector at the PEP-II asymmetric energy collider at the SLAC National Accelerator Laboratory, we measure the ratio R{sub {tau}{mu}} = BR({Upsilon}(1S) {yields} {tau}{sup +}{tau}{sup -})/BR({Upsilon}(1S) {yields} {mu}{sup +}{mu}{sup -}); the measurement is intended as a test of lepton universality and as a possible search for a light pseudoscalar Higgs boson in Next to Minimal Supersymmetric Standard Model (NMSSM) scenarios. Such a boson could appear in a deviation of the ratio R{sub {tau}{mu}} from the Standard Model expectation, that is 1, except for small lepton mass corrections. The analysis exploits the decays {Upsilon}(3S) {yields} {Upsilon}(1S){pi}{sup +}{pi}{sup -}, {Upsilon}(1S) {yields} l{sup +}l{sup -}, where l = {mu},{tau}.

Guido, Elisa; /Genoa U. /INFN, Genoa

2012-04-10T23:59:59.000Z

134

Search for the Higgs boson in lepton, tau, and jets final states  

SciTech Connect (OSTI)

We present a search for the standard model Higgs boson in final states with an electron or muon and a hadronically decaying tau lepton in association with two or more jets using 9.7 fb?1 of Run II Fermilab Tevatron Collider data collected with the D0 detector. The analysis is sensitive to Higgs boson production via gluon fusion, associated vector boson production, and vector boson fusion, followed by the Higgs boson decay to tau lepton pairs or to W boson pairs. The ratios of 95% C.L. upper limits on the cross section times branching ratio to those predicted by the standard model are obtained for orthogonal subsamples that are enriched in either H ? ? ? decays or H ? WW decays, and for the combination of these subsample limits. The observed and expected limit ratios for the combined subsamples at a Higgs boson mass of 125 GeV are 11.3 and 9.0 respectively.

Abazov, V.M.; et al.

2013-09-01T23:59:59.000Z

135

Search for the standard model Higgs boson in tau lepton final states  

SciTech Connect (OSTI)

We present a search for the standard model Higgs boson in final states with an electron or muon and a hadronically decaying tau lepton in association with zero, one, or two or more jets using data corresponding to an integrated luminosity of up to 7.3 fb{sup -1} collected with the D0 detector at the Fermilab Tevatron collider. The analysis is sensitive to Higgs boson production via gluon gluon fusion, associated vector boson production, and vector boson fusion, and to Higgs boson decays to tau lepton pairs or W boson pairs. Observed (expected) limits are set on the ratio of 95% C.L. upper limits on the cross section times branching ratio, relative to those predicted by the Standard Model, of 14 (22) at a Higgs boson mass of 115 GeV and 7.7 (6.8) at 165 GeV.

Abazov, Victor Mukhamedovich; et al.

2012-08-01T23:59:59.000Z

136

Search for the standard model Higgs boson in tau lepton pair final states  

E-Print Network [OSTI]

We present a search for the standard model Higgs boson in final states with an electron or muon and a hadronically decaying tau lepton in association with zero, one, or two or more jets using data corresponding to an integrated luminosity of up to 7.3 fb^{-1} collected with the D0 detector at the Fermilab Tevatron collider. The analysis is sensitive to Higgs boson production via gluon gluon fusion, associated vector boson production, and vector boson fusion, and to Higgs boson decays to tau lepton pairs or W boson pairs. Observed (expected) limits are set on the ratio of 95% C.L. upper limits on the cross section times branching ratio, relative to those predicted by the Standard Model, of 14 (22) at a Higgs boson mass of 115 GeV and 7.7 (6.8) at 165 GeV.

D0 Collaboration

2012-05-16T23:59:59.000Z

137

Measurement of J/psi leptonic width with the KEDR detector  

E-Print Network [OSTI]

We report a new precise determination of the leptonic widths of the J/psi meson performed with the KEDR detector at the VEPP-4M $e^{+}e^{-}$ collider. The measured values of the J/psi parameters are: \\Gamma_{ee}\\times\\Gamma_{ee}/\\Gamma = 0.3323 \\pm 0.0064 (stat.) \\pm 0.0048 (syst.) keV \\Gamma_{ee}\\times\\Gamma_{\\mu\\mu}/\\Gamma=0.3318 \\pm 0.0052 (stat.) \\pm 0.0063 (syst.) keV. Assuming $e\\mu$ universality and using the table value of the branching ratios the leptonic \\Gamma_{ll}= 5.59 \\pm 0.12 keV width and the total \\Gamma=94.1 \\pm 2.7 keV widths were obtained. We also discuss in detail a method to calculate radiative corrections at a narrow resonance.

Anashin, V V; Baldin, E M; Barladyan, A K; Barnyakov, A Yu; Barnyakov, M Yu; Baru, S E; Basok, I Yu; Beloborodova, O L; Blinov, A E; Blinov, V E; Bobrov, A V; Bobrovnikov, V S; Bogomyagkov, A V; Bondar, A E; Buzykaev, A R; Eidelman, S I; Grigoriev, D N; Glukhovchenko, Yu M; Gulevich, V V; Gusev, D V; Karnaev, S E; Karpov, G V; Karpov, S V; Kharlamova, T A; Kiselev, V A; Kolmogorov, V V; Kononov, S A; Kotov, K Yu; Kravchenko, E A; Kudryavtsev, V N; Kulikov, V F; Kurkin, G Ya; Kuper, E A; Levichev, E B; Maksimov, D A; Malyshev, V M; Maslennikov, A L; Medvedko, A S; Meshkov, O I; Mishnev, S I; Morozov, I I; Muchnoi, N Yu; Neufeld, V V; Nikitin, S A; Nikolaev, I B; Okunev, I N; Onuchin, A P; Oreshkin, S B; Orlov, I O; Osipov, A A; Peleganchuk, S V; Pivovarov, S G; Piminov, P A; Petrov, V V; Poluektov, A O; Prisekin, V G; Ruban, A A; Sandyrev, V K; Savinov, G A; Shamov, A G; Shatilov, D N; Shwartz, B A; Simonov, E A; Sinyatkin, S V; Skrinsky, A N; Smaluk, V V; Sokolov, A V; Sukharev, A M; Starostina, E V; Talyshev, A A; Tayursky, V A; Telnov, V I; Tikhonov, Yu A; Todyshev, K Yu; Tumaikin, G M; Usov, Yu V; Vorobiov, A I; Yushkov, A N; Zhilich, V N; Zhulanov, V V; Zhuravlev, A N

2011-01-01T23:59:59.000Z

138

Search for the Higgs boson in lepton, tau and jets final states  

E-Print Network [OSTI]

We present a search for the standard model Higgs boson in final states with an electron or muon and a hadronically decaying tau lepton in association with two or more jets using 9.7 fb^{-1} of Run II Fermilab Tevatron Collider data collected with the D0 detector. The analysis is sensitive to Higgs boson production via gluon fusion, associated vector boson production, and vector boson fusion, followed by the Higgs boson decay to tau lepton pairs or to W boson pairs. The ratios of 95% C.L. upper limits on the cross section times branching ratio to those predicted by the standard model are obtained for orthogonal subsamples that are enriched in either H -> tau tau decays or H -> WW decays, and for the combination of these subsample limits. The observed and expected limit ratios for the combined subsamples at a Higgs boson mass of 125 GeV are 11.3 and 9.0 respectively.

D0 Collaboration

2012-11-29T23:59:59.000Z

139

Symmetrical parametrizations of the lepton mixing matrix  

SciTech Connect (OSTI)

Advantages of the original symmetrical form of the parametrization of the lepton mixing matrix are discussed. It provides a conceptually more transparent description of neutrino oscillations and lepton number violating processes like neutrinoless double beta decay, clarifying the significance of Dirac and Majorana phases. It is also ideal for parametrizing scenarios with light sterile neutrinos.

Rodejohann, W. [Max-Planck-Institut fuer Kernphysik, Postfach 103980, 69029 Heidelberg (Germany); Valle, J. W. F. [AHEP Group, Institut de Fisica Corpuscular--C.S.I.C./Universitat de Valencia, Edificio Institutos de Paterna, Apt 22085, E-46071 Valencia (Spain)

2011-10-01T23:59:59.000Z

140

EIS-0138: Superconducting Super Collider  

Broader source: Energy.gov [DOE]

The U.S. Department of Energy developed this EIS to analyze the potential environmental impacts of constructing the Superconducting Super Collider, a large proton accelerator, at each of seven alternative locations.

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

New precise determination of the $\\tau$ lepton mass at KEDR detector  

E-Print Network [OSTI]

The status of the experiment on the precise $\\tau$ lepton mass measurement running at the VEPP-4M collider with the KEDR detector is reported. The mass value is evaluated from the $\\tau^+\\tau^-$ cross section behaviour around the production threshold. The preliminary result based on 6.7 pb$^{-1}$ of data is $m_{\\tau}=1776.80^{+0.25}_{-0.23} \\pm 0.15$ MeV. Using 0.8 pb$^{-1}$ of data collected at the $\\psi'$ peak the preliminary result is also obtained: $\\Gamma_{ee}B_{\\tau\\tau}(\\psi') = 7.2 \\pm 2.1$ eV.

Anashin, V V; Baldin, E M; Barladyan, A K; Barnyakov, A Y; Barnyakov, M Y; Baru, S E; Bedny, I V; Beloborodova, O L; Blinov, A E; Blinov, V E; Bobrov, A B; Bobrovnikov, V S; Bogomyagkov, A V; Bondar, A E; Bondarev, D V; Buzykaev, A R; Cherepanov, V P; Eidelman, S I; Glukhovchenko, Yu M; Gulevich, V V; Karnaev, S E; Karpov, G V; Karpov, S V; Kiselev, V A; Kononov, S A; Kotov, K Yu; Kravchenko, E A; Kremyanskaya, E V; Kulikov, V F; Kurkin, G Ya; Kuper, E A; Levichev, E B; Maksimov, D A; Malyshev, V M; Maslennikov, A L; Medvedko, A S; Meshkov, O I; Mishnev, S E; Morozov, I I; Muchnoi, N Yu; Neufeld, V V; Nikitin, S A; Nikolaev, I B; Onuchin, A P; Oreshkin, S B; Orlov, I O; Osipov, A A; Peleganchuk, S V; Petrosyan, S S; Pivovarov, S G; Piminov, P; Petrov, V V; Poluektov, A O; Pospelov, G E; Prisekin, V G; Ruban, A A; Sandyrev, V K; Savinov, G A; Shamov, A G; Shatilov, D N; Shubin, E I; Shwartz, B A; Sidorov, V A; Simonov, E A; Sinyatkin, S V; Skovpen, Y I; Skrinsky, A N; Smaluk, V V; Soukharev, A M; Struchalin, M V; Talyshev, A A; Tayursky, V A; Telnov, V I; Tikhonov, Yu A; Todyshev, K Y; Tumaikin, G M; Usov, Yu V; Vorobiov, A I; Yushkov, A N; Zhilich, V N; Zhuravlev, A N

2007-01-01T23:59:59.000Z

142

On Symmetric Lepton Mixing Matrices  

E-Print Network [OSTI]

Contrary to the quark mixing matrix, the lepton mixing matrix could be symmetric. We study the phenomenological consequences of this possibility. In particular, we find that symmetry would imply that |U_{e3}| is larger than 0.16, i.e., above its current 2 sigma limit. The other mixing angles are also constrained and CP violating effects in neutrino oscillations are suppressed, even though |U_{e3}| is sizable. Maximal atmospheric mixing is only allowed if the other observables are outside their current 3 sigma ranges, and sin^2 theta_{23} lies typically below 0.5. The Majorana phases are not affected, but the implied values of the solar neutrino mixing angle have some effect on the predictions for neutrinoless double beta decay. We further discuss some formal properties of a symmetric mixing matrix.

Hochmuth, K A; Hochmuth, Kathrin A.; Rodejohann, Werner

2007-01-01T23:59:59.000Z

143

Proton annihilation at hadron colliders and Kamioka: high-energy versus high-luminosity  

E-Print Network [OSTI]

We examine models and prospects for proton annihilation to dileptons, a process which violates baryon and lepton number each by two. We determine that currently Super-Kamiokande would place the most draconian bound on $pp \\rightarrow \\ell^+ \\ell^+$, ruling out new physics below a scale of $\\sim 1.6$ TeV. We also find present and future hadron collider sensitivity to these processes. While 8 TeV LHC data excludes new physics at a scale below $\\sim 800$ GeV, the reach of a 14 TeV LHC run is $\\sim 1.8$ TeV, putting it on par with the sensitivity of Super-Kamiokande. On the other hand, a 100 TeV proton-proton collider would be sensitive to proton annihilation at a scale up to 10 TeV, allowing it to far exceed the reach of both Super-Kamiokande and the projected 2 TeV reach of Hyper-Kamiokande. Constraints from neutron star observation and cosmological evolution are not competitive. Therefore, although high-luminosity water Cherenkov experiments currently place the leading bounds on baryon and lepton number violation, next generation high-energy hadron colliders will begin surpassing them in sensitivity to some $B/L$-violating processes.

Joseph Bramante; Jason Kumar; John Learned

2014-12-05T23:59:59.000Z

144

Search for Lepton-Flavor and Lepton-Number Violation in the Decay tau to lhh'  

SciTech Connect (OSTI)

A search for lepton-flavor and lepton-number violation in the decay of the tau lepton into one charged lepton and two charged hadrons is performed using 221.4 fb{sup -1} of data collected at an e{sup +}e{sup -} center-of-mass energy of 10.58 GeV with the BABAR detector at the PEP-II storage ring. In all 14 decay modes considered, the observed data are compatible with background expectations, and upper limits are set in the range {Beta}({tau} {yields} {ell}hh') < (0.7-4.8) x 10{sup -7} at 90% confidence level.

Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San

2005-06-29T23:59:59.000Z

145

Ground motion data for International Collider models  

SciTech Connect (OSTI)

The proposed location for the International Linear Collider (ILC) in the Americas region is Fermilab in Batavia Illinois. If built at this location the tunnels would be located in the Galena Platteville shale at a depth of 100 or more meters below the surface. Studies using hydro static water levels and seismometers have been conducted in the MINOS hall and the LaFrange Mine in North Aurora Illinois to determine the level of ground motion. Both these locations are in the Galena Platteville shale and indicate the typical ground motion to be expected for the ILC. The data contains both natural and cultural noise. Coefficients for the ALT law are determined. Seismic measurements at the surface and 100 meters below the surface are presented.

Volk, J.T.; LeBrun, P.; Shiltsev, V.; Singatulin, S.; /Fermilab

2007-11-01T23:59:59.000Z

146

Muon collider interaction region design  

SciTech Connect (OSTI)

Design of a muon collider interaction region (IR) presents a number of challenges arising from low {beta}* < 1 cm, correspondingly large beta-function values and beam sizes at IR magnets, as well as the necessity to protect superconducting magnets and collider detectors from muon decay products. As a consequence, the designs of the IR optics, magnets and machine-detector interface are strongly interlaced and iterative. A consistent solution for the 1.5 TeV c.o.m. muon collider IR is presented. It can provide an average luminosity of 10{sup 34} cm{sup -2}s{sup -1} with an adequate protection of magnet and detector components.

Alexahin, Y.I.; Gianfelice-Wendt, E.; Kashikhin, V.V.; Mokhov, N.V.; Zlobin, A.V.; /Fermilab; Alexakhin, V.Y.; /Dubna, JINR

2010-05-01T23:59:59.000Z

147

Search for the associated production of the Higgs boson with a top quark pair in multi-lepton final states with the ATLAS detector  

E-Print Network [OSTI]

A search for the associated production of the Higgs boson with a top quark pair is performed in multi-lepton final states using 20.3 fb$^{-1}$ of proton-proton collision data recorded by the ATLAS experiment at $\\sqrt{s}=8$ TeV at the Large Hadron Collider. Five final states, targeting the decays $H\\to WW^*$, $\\tau\\tau$, and $ZZ^*$, are examined for the presence of the Standard Model (SM) Higgs boson: two same-charged light leptons ($e$ or $\\mu$) without an additional hadronically decaying tau; three light leptons; two same-charged light leptons with an additional hadronically decaying tau; four light leptons; and one light lepton and two hadronically decaying taus. No significant excess of events is observed above the background expectation. The best fit for the $t\\bar t H$ production cross section, assuming a Higgs boson mass of 125 GeV, is $2.1 ^{+1.4}_{-1.2}$ times the SM expectation, and the observed (expected) upper limit at the 95% confidence level is 4.7 (2.4) times the SM rate. The $p$-value for comp...

The ATLAS collaboration

2015-01-01T23:59:59.000Z

148

Detectors for Linear Colliders: Tracking and Vertexing (2/4)  

ScienceCinema (OSTI)

Efficient and precise determination of the flavour of partons in multi-hadron final states is essential to the anticipated LC physics program. This makes tracking in the vicinity of the interaction region of great importance. Tracking extrapolation and momentum resolution are specified by precise physics requirements. The R&D; towards detectors able to meet these specifications will be discussed, together with some of their application beyond particle physics.

None

2011-10-06T23:59:59.000Z

149

International Linear Collider Accelerator Physics R&D  

SciTech Connect (OSTI)

ILC work at Illinois has concentrated primarily on technical issues relating to the design of the accelerator. Because many of the problems to be resolved require a working knowledge of classical mechanics and electrodynamics, most of our research projects lend themselves well to the participation of undergraduate research assistants. The undergraduates in the group are scientists, not technicians, and find solutions to problems that, for example, have stumped PhD-level staff elsewhere. The ILC Reference Design Report calls for 6.7 km circumference damping rings (which prepare the beams for focusing) using “conventional” stripline kickers driven by fast HV pulsers. Our primary goal was to determine the suitability of the 16 MeV electron beam in the AØ region at Fermilab for precision kicker studies.We found that the low beam energy and lack of redundancy in the beam position monitor system complicated the analysis of our data. In spite of these issues we concluded that the precision we could obtain was adequate to measure the performance and stability of a production module of an ILC kicker, namely 0.5%. We concluded that the kicker was stable to an accuracy of ~2.0% and that we could measure this precision to an accuracy of ~0.5%. As a result, a low energy beam like that at AØ could be used as a rapid-turnaround facility for testing ILC production kicker modules. The ILC timing precision for arrival of bunches at the collision point is required to be 0.1 picosecond or better. We studied the bunch-to-bunch timing accuracy of a “phase detector” installed in AØ in order to determine its suitability as an ILC bunch timing device. A phase detector is an RF structure excited by the passage of a bunch. Its signal is fed through a 1240 MHz high-Q resonant circuit and then down-mixed with the AØ 1300 MHz accelerator RF. We used a kind of autocorrelation technique to compare the phase detector signal with a reference signal obtained from the phase detector’s response to an event at the beginning of the run. We determined that the device installed in our beam, which was instrumented with an 8-bit 500 MHz ADC, could measure the beam timing to an accuracy of 0.4 picoseconds. Simulations of the device showed that an increase in ADC clock rate to 2 GHz would improve measurement precision by the required factor of four. As a result, we felt that a device of this sort, assuming matters concerning dynamic range and long-term stability can be addressed successfully, would work at the ILC. Cost effective operation of the ILC will demand highly reliable, fault tolerant and adaptive solutions for both hardware and software. The large numbers of subsystems and large multipliers associated with the modules in those subsystems will cause even a strong level of unit reliability to become an unacceptable level of system availability. An evaluation effort is underway to evaluate standards associated with high availability, and to guide ILC development with standard practices and well-supported commercial solutions. One area of evaluation involves the Advanced Telecom Computing Architecture (ATCA) hardware and software. We worked with an ATCA crate, processor monitors, and a small amount of ATCA circuit boards in order to develop a backplane “spy” board that would let us watch the ATCA backplane communications and pursue development of an inexpensive processor monitor that could be used as a physics-driven component of the crate-level controls system. We made good progress, and felt that we had determined a productive direction to extend this work. We felt that we had learned enough to begin designing a workable processor monitor chip if there were to be sufficient interest in ATCA shown by the ILC community. Fault recognition is a challenging issue in the crafting a high reliability controls system. With tens of thousands of independent processors running hundreds of thousands of critical processes, how can the system identify that a problem has arisen and determine the appropriate steps to take to correct, or compensate, for the

George D. Gollin; Michael Davidsaver; Michael J. Haney; Michael Kasten; Jason Chang; Perry Chodash; Will Dluger; Alex Lang; Yehan Liu

2008-09-03T23:59:59.000Z

150

acceleration linear collider: Topics by E-print Network  

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

breaking. Many extensions of the standard model have a decoupling limit, with a Higgs boson similar to the standard one and other, higher-mass states. Mindful of such...

151

International Linear Collider Technical Design Report (Volumes 1 through 4)  

SciTech Connect (OSTI)

The design report consists of four volumes: Volume 1, Executive Summary; Volume 2, Physics; Volume 3, Accelerator (Part I, R and D in the Technical Design Phase, and Part II, Baseline Design); and Volume 4, Detectors.

Harrison M.

2013-03-27T23:59:59.000Z

152

Precision measurement of a particle mass at the linear collider  

SciTech Connect (OSTI)

Precision measurement of the stop mass at the ILC is done in a method based on cross-sections measurements at two different center-of-mass energies. This allows to minimize both the statistical and systematic errors. In the framework of the MSSM, a light stop, compatible with electro-weak baryogenesis, is studied in its decay into a charm jet and neutralino, the Lightest Supersymmetric Particle (LSP), as a candidate of dark matter. This takes place for a small stop-neutralino mass difference.

Milstene, C.; /Fermilab; Freitas, A.; /Zurich U.; Schmitt, M.; /Northwestern U.; Sopczak, A.; /Lancaster U.

2007-06-01T23:59:59.000Z

153

SLAC-R-1004 International Linear Collider Technical  

Office of Scientific and Technical Information (OSTI)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article: CrystalFG36-08GO18149SpeedingRenewable Energy Agricultural &7842 1R-1004

154

SciTech Connect: International Linear Collider Technical Design Report -  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBi (2) Sr (2) Ca (2) Cu (3)GettingGeochemical Process Relevant

155

JLab Supports International Linear Collider Cavity Development Work |  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared LandResponsesIon/SurfacePump-TestingJEDI: JobsTimothy|Scientist

156

Detectors for Linear Colliders: Detector design for a Future Electron-Positron Collider (4/4)  

ScienceCinema (OSTI)

In this lecture I will discuss the issues related to the overall design and optimization of a detector for ILC and CLIC energies. I will concentrate on the two main detector concepts which are being developed in the context of the ILC. Here there has been much recent progress in developing realistic detector models and in understanding the physics performance of the overall detector concept. In addition, I will discuss the how the differences in the detector requirements for the ILC and CLIC impact the overall detector design.

None

2011-10-06T23:59:59.000Z

157

Colliding axisymmetric pp-waves  

E-Print Network [OSTI]

An exact solution is found describing the collision of axisymmetric pp-waves with M=0. They are impulsive in character and their coordinate singularities become point curvature singularities at the boundaries of the interaction region. The solution is conformally flat. Concrete examples are given, involving an ultrarelativistic black hole against a burst of pure radiation or two colliding beam- like waves.

B. V. Ivanov

1997-10-21T23:59:59.000Z

158

Muon Colliders: The Next Frontier  

ScienceCinema (OSTI)

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.

Yagmur Tourun

2010-01-08T23:59:59.000Z

159

Measuring the Higgs boson mass in dileptonic W-boson decays at hadron colliders  

E-Print Network [OSTI]

ar X iv :0 90 2. 48 64 v2 [ he p- ph ] 22 Ju l 2 00 9 Cavendish-HEP-09/04 Measuring the Higgs boson mass in dileptonic W -boson decays at hadron colliders Alan J. Barr,1, ? Ben Gripaios,2, † and Christopher G. Lester3, ‡ 1Denys Wilkinson... measurements of the Higgs boson mass using the decay h ? W+W?, followed by the leptonic decay of each W -boson, will be performed by fitting the shape of a distribution that is sensitive to the Higgs mass. We demonstrate that the variable most commonly used...

Barr, Alan; Gripaios, Ben; Lester, Christopher G

2009-01-01T23:59:59.000Z

160

Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism.  

E-Print Network [OSTI]

ar X iv :0 90 2. 46 97 v1 [ he p- ph ] 26 Fe b 2 00 9 CAVENDISH-HEP-2009-03, DAMTP-2009-15, DO-TH-09/01 Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism B. C. Allanach? DAMTP, University of Cambridge... ) In the minimal supersymmetric extension to the Standard Model, a non-zero lepton number violating coupling ??111 predicts both neutrinoless double beta decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double...

Allanach, B C; Kom, C H; Pas, H

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161

Search for chargino and neutralino at Run II of the Tevatron Collider  

SciTech Connect (OSTI)

In this dissertation we present a search for the associated production of charginos and neutralinos, the supersymmetric partners of the Standard Model bosons. We analyze a data sample representing 745 pb{sup -1} of integrated luminosity collected by the CDF experiment at the p{bar p} Tevatron collider. We compare the Standard Model predictions with the observed data selecting events with three leptons and missing transverse energy. Finding no excess, we combine the results of our search with similar analyses carried out at CDF and set an upper limit on the chargino mass in SUSY scenarios.

Canepa, Anadi; /Purdue U.

2006-08-01T23:59:59.000Z

162

2005 International Linear Collider Workshop Stanford, U.S.A. Selectron Mass Reconstruction and the Resolution of the Linear Collider  

E-Print Network [OSTI]

to isolate the forward selectron-decay signal from Standard-Model backgrounds, as well as techniques on the results of those studies. 2. SIGNAL SELECTION Backgrounds to the selectron-decay electron signal come from in angle to the beam trajectory, and thus escape detection, and the Z-boson fusion process e+ e- e+ e

California at Santa Cruz, University of

163

Muon Muon Collider: Feasibility Study  

SciTech Connect (OSTI)

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle reactions which are open to a muon collider and the physics of such reactions - what one learns and the necessary luminosity to see interesting events - are described in detail. Most of the physics accesible to an e{sup +} - e{sup -} collider could be studied in a muon collider. In addition the production of Higgs bosons in the s-channel will allow the measurement of Higgs masses and total widths to high precision; likewise, t{bar t} and W{sup +}W{sup -} threshold studies would yield m{sub t} and m{sub w} to great accuracy. These reactions are at low center of mass energy (if the MSSM is correct) and the luminosity and {Delta}p/p of the beams required for these measurements is detailed in the Physics Chapter. On the other hand, at 2 + 2 TeV, a luminosity of L {approx} 10{sup 35} cm{sup -2}s{sup -1} is desirable for studies such as, the scattering of longitudinal W bosons or the production of heavy scalar particles. Not explored in this work, but worth noting, are the opportunities for muon-proton and muon-heavy ion collisions as well as the enormous richness of such a facility for fixed target physics provided by the intense beams of neutrinos, muons, pions, kaons, antiprotons and spallation neutrons. To see all the interesting physics described herein requires a careful study of the operation of a detector in the very large background. Three sources of background have been identified. The first is from any halo accompanying the muon beams in the collider ring. Very carefully prepared beams will have to be injected and maintained. The second is due to the fact that on average 35% of the muon energy appears in its decay electron. The energy of the electron subsequently is converted into EM showers either from the synchrotron radiation they emit in the collider magnetic field or from direct collision with the surrounding material. The decays that occur as the beams traverse the low beta insert are of particular concern for detector backgrounds. A third source of background is e{sup +} - e{sup -} pair creation from {mu}{sup +} - {mu}{sup -} interaction. Studies of

Gallardo, J.C.; Palmer, R.B.; /Brookhaven; Tollestrup, A.V.; /Fermilab; Sessler, A.M.; /LBL, Berkeley; Skrinsky, A.N.; /Novosibirsk, IYF; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. /Fermilab /Brookhaven /Wisconsin U., Madison /Tel Aviv U. /Indiana U. /UCLA /LBL, Berkeley /SLAC /Argonne /Sobolev IM, Novosibirsk /UC, Davis /Munich, Tech. U. /Virginia U. /KEK, Tsukuba /DESY /Novosibirsk, IYF /Jefferson Lab /Mississippi U. /SUNY, Stony Brook /MIT /Columbia U. /Fairfield U. /UC, Berkeley; ,

2012-04-05T23:59:59.000Z

164

Search for supersymmetry at sqrt(s)=8 TeV in final states with jets and two same-sign leptons or three leptons with the ATLAS detector  

E-Print Network [OSTI]

A search for strongly produced supersymmetric particles is conducted using signatures involving multiple energetic jets and either two isolated leptons ($e$ or $\\mu$) with the same electric charge, or at least three isolated leptons. The search also utilises jets originating from b-quarks, missing transverse momentum and other observables to extend its sensitivity. The analysis uses a data sample corresponding to a total integrated luminosity of 20.3 fb$^{-1}$ of $\\sqrt{s} =$ 8 TeV proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider in 2012. No deviation from the Standard Model expectation is observed. New or significantly improved exclusion limits are set on a wide variety of supersymmetric models in which the lightest squark can be of the first, second or third generations, and in which R-parity can be conserved or violated.

ATLAS Collaboration

2014-04-09T23:59:59.000Z

165

The Lepton Sector of a Fourth Generation  

E-Print Network [OSTI]

In extensions of the standard model with a heavy fourth generation one important question is what makes the fourth-generation lepton sector, particularly the neutrinos, so different from the lighter three generations. We study this question in the context of models of electroweak symmetry breaking in warped extra dimensions, where the flavor hierarchy is generated by the localization of the zero-mode fermions in the extra dimension. In this setup the Higgs sector is localized near the infrared brane, whereas the Majorana mass term is localized at the ultraviolet brane. As a result, light neutrinos are almost entirely Majorana particles, whereas the fourth generation neutrino is mostly a Dirac fermion. We show that it is possible to obtain heavy fourth-generation leptons in regions of parameter space where the light neutrino masses and mixings are compatible with observation. We study the impact of these bounds, as well as the ones from lepton flavor violation, on the phenomenology of these models.

Gustavo Burdman; Leandro Da Rold; Ricardo D. Matheus

2010-05-10T23:59:59.000Z

166

Probing lepton number violation on three frontiers  

SciTech Connect (OSTI)

Neutrinoless double beta decay constitutes the main probe for lepton number violation at low energies, motivated by the expected Majorana nature of the light but massive neutrinos. On the other hand, the theoretical interpretation of the (non-)observation of this process is not straightforward as the Majorana neutrinos can destructively interfere in their contribution and many other New Physics mechanisms can additionally mediate the process. We here highlight the potential of combining neutrinoless double beta decay with searches for Tritium decay, cosmological observations and LHC physics to improve the quantitative insight into the neutrino properties and to unravel potential sources of lepton number violation.

Deppisch, Frank F. [Department of Physics and Astronomy, University College London (United Kingdom)

2013-12-30T23:59:59.000Z

167

Tutorial guide to the tau lepton and close-mass lepton pairs  

SciTech Connect (OSTI)

This is a tutorial guide to present knowledge of the tau lepton, to the tau decay mode puzzle, and to present searches for close-mass lepton pairs. The test is minimal; the emphasis is on figures, tables and literature references. It is based on a lecture given at the 1988 International School of Subnuclear Physics: The Super World III. 54 refs., 9 figs., 7 tabs.

Perl, M.L.

1988-10-01T23:59:59.000Z

168

Study of Top-Quark Production and Decays involving a Tau Lepton at CDF and Limits on a Charged-Higgs Boson Contribution  

E-Print Network [OSTI]

We present an analysis of top-antitop quark production and decay into a tau lepton, tau neutrino, and bottom quark using data from $9 {\\rm fb}^{-1}$ of integrated luminosity at the Collider Detector at Fermilab. Dilepton events, where one lepton is an energetic electron or muon and the other a hadronically-decaying tau lepton, originating from proton-antiproton collisions at $\\sqrt{s} = 1.96 TeV$ are used. A top-antitop quark production cross section of $8.1 \\pm 2.1 {\\rm pb}$ is measured, assuming standard-model top-quark decays. By separately identifying for the first time the single-tau and the ditau components, we measure the branching fraction of the top quark into tau lepton, tau neutrino, and bottom quark to be $(9.6 \\pm 2.8) %$. The branching fraction of top-quark decays into a charged Higgs boson and a bottom quark, which would imply violation of lepton universality, is limited to be less than $5.9%$ at $95%$ confidence level.

CDF Collaboration; T. Aaltonen; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; J. A. Appel; T. Arisawa; A. Artikov; J. Asaadi; W. Ashmanskas; B. Auerbach; A. Aurisano; F. Azfar; W. Badgett; T. Bae; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Barria; P. Bartos; M. Bauce; F. Bedeschi; S. Behari; G. Bellettini; J. Bellinger; D. Benjamin; A. Beretvas; A. Bhatti; K. R. Bland; B. Blumenfeld; A. Bocci; A. Bodek; D. Bortoletto; J. Boudreau; A. Boveia; L. Brigliadori; C. Bromberg; E. Brucken; J. Budagov; H. S. Budd; K. Burkett; G. Busetto; P. Bussey; P. Butti; A. Buzatu; A. Calamba; S. Camarda; M. Campanelli; F. Canelli; B. Carls; D. Carlsmith; R. Carosi; S. Carrillo; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; V. Cavaliere; M. Cavalli-Sforza; A. Cerri; L. Cerrito; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; K. Cho; D. Chokheli; A. Clark; C. Clarke; M. E. Convery; J. Conway; M. Corbo; M. Cordelli; C. A. Cox; D. J. Cox; M. Cremonesi; D. Cruz; J. Cuevas; R. Culbertson; N. d'Ascenzo; M. Datta; P. de Barbaro; L. Demortier; L. Marchese; M. Deninno; F. Devoto; M. D'Errico; A. Di Canto; B. Di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; M. Dorigo; A. Driutti; K. Ebina; R. Edgar; A. Elagin; R. Erbacher; S. Errede; B. Esham; S. Farrington; J. P. Fernández Ramos; R. Field; G. Flanagan; R. Forrest; M. Franklin; J. C. Freeman; H. Frisch; Y. Funakoshi; C. Galloni; A. F. Garfinkel; P. Garosi; H. Gerberich; E. Gerchtein; S. Giagu; V. Giakoumopoulou; K. Gibson; C. M. Ginsburg; N. Giokaris; P. Giromini; G. Giurgiu; V. Glagolev; D. Glenzinski; M. Gold; D. Goldin; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González López; I. Gorelov; A. T. Goshaw; K. Goulianos; E. Gramellini; S. Grinstein; C. Grosso-Pilcher; R. C. Group; J. Guimaraes da Costa; S. R. Hahn; J. Y. Han; F. Happacher; K. Hara; M. Hare; R. F. Harr; T. Harrington-Taber; K. Hatakeyama; C. Hays; J. Heinrich; M. Herndon; A. Hocker; Z. Hong; W. Hopkins; S. Hou; R. E. Hughes; U. Husemann; M. Hussein; J. Huston; G. Introzzi; M. Iori; A. Ivanov; E. James; D. Jang; B. Jayatilaka; E. J. Jeon; S. Jindariani; M. Jones; K. K. Joo; S. Y. Jun; T. R. Junk; M. Kambeitz; T. Kamon; P. E. Karchin; A. Kasmi; Y. Kato; W. Ketchum; J. Keung; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; Y. J. Kim; N. Kimura; M. Kirby; K. Knoepfel; K. Kondo; D. J. Kong; J. Konigsberg; A. V. Kotwal; M. Kreps; J. Kroll; M. Kruse; T. Kuhr; M. Kurata; A. T. Laasanen; S. Lammel; M. Lancaster; K. Lannon; G. Latino; H. S. Lee; J. S. Lee; S. Leo; S. Leone; J. D. Lewis; A. Limosani; E. Lipeles; A. Lister; H. Liu; Q. Liu; T. Liu; S. Lockwitz; A. Loginov; A. Lucà; D. Lucchesi; J. Lueck; P. Lujan; P. Lukens; G. Lungu; J. Lys; R. Lysak; R. Madrak; P. Maestro; S. Malik; G. Manca; A. Manousakis-Katsikakis; F. Margaroli; P. Marino; M. Martínez; K. Matera; M. E. Mattson; A. Mazzacane; P. Mazzanti; R. McNulty; A. Mehta; P. Mehtala; C. Mesropian; T. Miao; D. Mietlicki; A. Mitra; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. J. Morello; A. Mukherjee; Th. Muller; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; J. Naganoma; I. Nakano; A. Napier; J. Nett; C. Neu; T. Nigmanov; L. Nodulman; S. Y. Noh; O. Norniella; L. Oakes; S. H. Oh; Y. D. Oh; I. Oksuzian; T. Okusawa; R. Orava; L. Ortolan; C. Pagliarone; E. Palencia; P. Palni; V. Papadimitriou; W. Parker; G. Pauletta; M. Paulini; C. Paus; T. J. Phillips; G. Piacentino; E. Pianori; J. Pilot; K. Pitts; C. Plager; L. Pondrom; S. Poprocki; K. Potamianos; F. Prokoshin; A. Pranko; F. Ptohos; G. Punzi; N. Ranjan; I. Redondo Fernández; P. Renton; M. Rescigno; F. Rimondi; L. Ristori; C. Rizzi; A. Robson; T. Rodriguez; S. Rolli; M. Ronzani; R. Roser; J. L. Rosner; F. Ruffini; A. Ruiz; J. Russ; V. Rusu; W. K. Sakumoto; Y. Sakurai; L. Santi; K. Sato; V. Saveliev; A. Savoy-Navarro; P. Schlabach; E. E. Schmidt; T. Schwarz; L. Scodellaro; F. Scuri; S. Seidel; Y. Seiya; A. Semenov; F. Sforza; S. Z. Shalhout; T. Shears; P. F. Shepard; M. Shimojima; M. Shochet; I. Shreyber-Tecker; A. Simonenko; K. Sliwa; J. R. Smith; F. D. Snider; V. Sorin; H. Song; M. Stancari; R. St. Denis; D. Stentz; J. Strologas; Y. Sudo; A. Sukhanov; I. Suslov; K. Takemasa; Y. Takeuchi; J. Tang; M. Tecchio; P. K. Teng; J. Thom; E. Thomson; V. Thukral; D. Toback; S. Tokar; K. Tollefson; T. Tomura; D. Tonelli; S. Torre; D. Torretta; P. Totaro; M. Trovato; F. Ukegawa; S. Uozumi; F. Vázquez; G. Velev; C. Vellidis; C. Vernieri; M. Vidal; R. Vilar; J. Vizán; M. Vogel; G. Volpi; P. Wagner; R. Wallny; S. M. Wang; D. Waters; W. C. Wester III; D. Whiteson; A. B. Wicklund; S. Wilbur; H. H. Williams; J. S. Wilson; P. Wilson; B. L. Winer; P. Wittich; S. Wolbers; H. Wolfe; T. Wright; X. Wu; Z. Wu; K. Yamamoto; D. Yamato; T. Yang; U. K. Yang; Y. C. Yang; W. -M. Yao; G. P. Yeh; K. Yi; J. Yoh; K. Yorita; T. Yoshida

2014-04-22T23:59:59.000Z

169

Tevatron instrumentation: boosting collider performance  

SciTech Connect (OSTI)

The Tevatron in Collider Run II (2001-present) is operating with six times more bunches, many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for the next big machines--LHC and ILC.

Shiltsev, Vladimir; Jansson, Andreas; Moore, Ronald; /Fermilab

2006-05-01T23:59:59.000Z

170

Probing Higgs Boson Interactions At Future Colliders.  

E-Print Network [OSTI]

??We present in this thesis a detailed analysis of Higgs boson interactions at future colliders. In particular we examine, in a model independent way, the… (more)

Biswal, Sudhansu Sekhar

2009-01-01T23:59:59.000Z

171

Hadron colliders (SSC/LHC)  

SciTech Connect (OSTI)

The nominal SSC and LHC designs should operate conservatively at luminosities up to 10{sup 33} cm{sup {minus}2} s{sup {minus}1}. This luminosity is dictated by the event rates that can be handled by the detectors. However, this limit is event dependent (e.g. it does not take much of a detector to detect the event pp {yields} elephant; all one needs is extremely high luminosity). As such, it is useful to explore the possibility of going beyond the 10{sup 33} cm{sup {minus}2} s{sup {minus}1} level. Such exploration will also improve the accelerator physics understanding of pp collider designs. If the detector limitations are removed, the first accelerator limits occur when the luminosity is at the level of 10{sup 34} cm{sup {minus}2}s{sup {minus}1}. These accelerator limits will first be reviewed. The authors will then continue on to explore even higher luminosity as the ultimate limit of pp colliders. Accelerator technologies needed to achieve this ultimate luminosity as well as the R and D needed to reach it are discussed.

Chao, A.W. [Superconducting Super Collider Lab., Dallas, TX (United States); Palmer, R.B. [Superconducting Super Collider Lab., Dallas, TX (United States); [Stanford Linear Accelerator Center, CA (United States); Evans, L.; Gareyte, J. [CERN, Geneva (Switzerland); Siemann, R.H. [Cornell Univ., Ithaca, NY (United States)

1992-12-31T23:59:59.000Z

172

Stochastic cooling in muon colliders  

SciTech Connect (OSTI)

Analysis of muon production techniques for high energy colliders indicates the need for rapid and effective beam cooling in order that one achieve luminosities > 10{sup 30} cm{sup {minus}2}s{sup {minus}1} as required for high energy physics experiments. This paper considers stochastic cooling to increase the phase space density of the muons in the collider. Even at muon energies greater than 100 GeV, the number of muons per bunch must be limited to {approximately}10{sup 3} for the cooling rate to be less than the muon lifetime. With such a small number of muons per bunch, the final beam emittance implied by the luminosity requirement is well below the thermodynamic limit for beam electronics at practical temperatures. Rapid bunch stacking after the cooling process can raise the number of muons per bunch to a level consistent with both the luminosity goals and with practical temperatures for the stochastic cooling electronics. A major advantage of our stochastic cooling/stacking scheme over scenarios that employ only ionization cooling is that the power on the production target can be reduced below 1 MW.

Barletta, W.A.; Sessler, A.M.

1993-09-01T23:59:59.000Z

173

Precise measurement of the top-quark mass from lepton+jets events at D0  

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

We report a measurement of the mass of the top quark in lepton+jets final states of pp&3772; ? tt? data corresponding to 2.6 fb-1 of integrated luminosity collected at the D0 experiment at the Fermilab Tevatron Collider. Using a matrix element method, we combine an in situ jet energy calibration with the standard jet energy scale derived in studies of ? + jet and dijet events and employ a novel flavor-dependent jet response correction to measure a top-quark mass of mt = 176.01 ± 1.64 GeV. Combining this result with a previous result obtained on an independent data set, we measure a top-quark mass of mt = 174.94 ± 1.49 GeV for a total integrated luminosity of 3.6 fb-1.

Abazov, Victor Mukhamedovich [Dubna, JINR; Abbott, Braden Keim [Oklahoma U.; Acharya, Bannanje Sripath [Tata Inst.; Adams, Mark Raymond [Illinois U., Chicago; Adams, Todd [Florida State U.; Alexeev, Guennadi D [Dubna, JINR; Alkhazov, Georgiy D [St. Petersburg, INP; Alton, Andrew K [Michigan U.; Augustana Coll., Sioux Falls; Alverson, George O [Northeastern U.; Alves, Gilvan Augusto [Rio de Janeiro, CBPF; Ancu, Lucian Stefan [Nijmegen U.; Fermilab

2011-08-09T23:59:59.000Z

174

Precise measurement of the top-quark mass from lepton+jets events at D0  

SciTech Connect (OSTI)

We report a measurement of the mass of the top quark in lepton+jets final states of pp&3772; ? tt? data corresponding to 2.6 fb-1 of integrated luminosity collected at the D0 experiment at the Fermilab Tevatron Collider. Using a matrix element method, we combine an in situ jet energy calibration with the standard jet energy scale derived in studies of ? + jet and dijet events and employ a novel flavor-dependent jet response correction to measure a top-quark mass of mt = 176.01 ± 1.64 GeV. Combining this result with a previous result obtained on an independent data set, we measure a top-quark mass of mt = 174.94 ± 1.49 GeV for a total integrated luminosity of 3.6 fb-1.

Abazov, Victor Mukhamedovich [Dubna, JINR; Abbott, Braden Keim [Oklahoma U.; Acharya, Bannanje Sripath [Tata Inst.; Adams, Mark Raymond [Illinois U., Chicago; Adams, Todd [Florida State U.; Alexeev, Guennadi D [Dubna, JINR; Alkhazov, Georgiy D [St. Petersburg, INP; Alton, Andrew K [Michigan U.; Augustana Coll., Sioux Falls; Alverson, George O [Northeastern U.; Alves, Gilvan Augusto [Rio de Janeiro, CBPF; Ancu, Lucian Stefan [Nijmegen U.; Fermilab

2011-08-09T23:59:59.000Z

175

PDF uncertainties on the W boson mass measurement from the lepton transverse momentum distribution  

E-Print Network [OSTI]

We study the charged current Drell-Yan process and we evaluate the proton parton densities uncertainties on the lepton transverse momentum distribution and their impact on the determination of the W-boson mass. We consider the global PDF sets CT10, MSTW2008CPdeut, NNPDF2.3, NNPDF3.0, MMHT2014, and apply the PDF4LHC recipe to combine the individual results, obtaining an uncertainty on MW that ranges between +-18 and +-24 MeV, depending on the final state, collider energy and kind. We discuss the dependence of the uncertainty on the acceptance cuts and the role of the individual parton densities in the final result. We remark that some PDF sets predict an uncertainty on MW of O(10 MeV); this encouraging result is spoiled, in the combined analysis of the different sets, by an important spread of the central values predicted by each group.

Bozzi, Giuseppe; Vicini, Alessandro

2015-01-01T23:59:59.000Z

176

Test of lepton universality and search for lepton flavor violation in Upsilon(1S,2S,3S) decays at CLEO  

E-Print Network [OSTI]

We present the analysis technique and preliminary results of two ongoing analyses at CLEO which put lepton universality and lepton flavor conservation to the test in Upsilon decays.

Istvan Danko; for the CLEO Collaboration

2006-01-18T23:59:59.000Z

177

Collider searches and cosmology in the MSSM with heavy scalars  

SciTech Connect (OSTI)

In a variety of supersymmetric extensions of the Standard Model, the scalar partners of the quarks and leptons are predicted to be very heavy and beyond the reach of next-generation colliders. For instance, the realization of electroweak baryogenesis in supersymmetry requires new sources of CP-violation, which can only be naturally accommodated with electric dipole moment constraints if the first and second generation scalar fermions are beyond the TeV scale. Also in focus-point supersymmetry and split supersymmetry the scalar fermions are very heavy. In this work, the phenomenology of scenarios with electroweak baryogenesis and in the focus point region at the LHC and ILC is studied, which becomes challenging due to the presence of heavy scalar fermions. Implications for the analysis of baryogenesis and dark matter are deduced. It is found that precision measurements of superpartner properties allow an accurate determination of the dark matter relic density in both scenarios, while important but only incomplete information about the baryogenesis mechanism can be obtained.

Carena, Marcela; /Fermilab; Freitas, A.; /Zurich U.

2006-08-01T23:59:59.000Z

178

Simplified unitarity triangles for the lepton sector  

SciTech Connect (OSTI)

Encouraged by the latest SNO results, we consider the lepton mixing matrix in the approximation that the {nu}{sub 2} mass eigenstate is trimaximally (democratically) mixed. This suggests a new parameterization of the remaining mixing degrees of freedom, which eschews mixing angles, dealing instead, directly with the complex parameter U{sub e3} of the mixing matrix. Unitarity triangles then take a particularly simple form, which we hope will facilitate comparison with experiment.

Bjorken, James D. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States); Harrison, P. F. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Scott, W. G. [CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX, UK (United Kingdom)

2006-10-01T23:59:59.000Z

179

Lepton Flavor Violation in Flavored Gauge Mediation  

E-Print Network [OSTI]

We study the anatomy and phenomenology of Lepton Flavor Violation (LFV) in the context of Flavored Gauge Mediation (FGM). Within FGM, the messenger sector couples directly to the MSSM matter fields with couplings controlled by the same dynamics that explains the hierarchies in the SM Yukawas. Although the pattern of flavor violation depends on the particular underlying flavor model, FGM provides a built-in flavor suppression similar to wave function renormalization or SUSY Partial Compositeness. Moreover, in contrast to these models, there is an additional suppression of left-right (LR) flavor transitions by third-generation Yukawas that in particular provides an extra protection against flavor-blind phases. We exploit the consequences of this setup for lepton flavor phenomenology, assuming that the new couplings are controlled by simple U(1) flavor models that have been proposed to accommodate large neutrino mixing angles. Remarkably, it turns out that in the context of FGM these models can pass the impressive constraints from LFV processes and leptonic EDMs even for light superpartners, therefore offering the possibility of resolving the longstanding muon g-2 anomaly.

Lorenzo Calibbi; Paride Paradisi; Robert Ziegler

2014-08-04T23:59:59.000Z

180

Study of high pressure gas filled RF cavities for muon collider  

E-Print Network [OSTI]

Muon collider is a considerable candidate of the next-generation high-energy lepton collider machine. Operating an RF cavity in a multi-Tesla magnet is a critical requirement in a muon accelerator and a cooling channel. However, the maximum RF gradient in a vacuum RF cavity is strongly limited by an external magnetic field. Dense hydrogen gas filled RF cavity has been proposed since it is functional of generating a high RF accelerating gradient in a strong magnetic field and making an ionization cooling process at the same time. A critical issue of the cavity is a beam- induced plasma that consumes a considerable amount of RF power. The gas filled RF test cell was made and measured the RF loading due to a beam-induced plasma by using an intense proton beam at Fermilab. By doping an electronegative gas in dense hydrogen, the plasma loading effect is significantly mitigated. The result shows that the cavity is functional with a muon collider beam. Recent progress is shown in this presentation.

Yonehara, Katsuya

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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181

New Physics at the LHC: A Les Houches Report. Physics at Tev Colliders 2007 - New Physics Working Group  

SciTech Connect (OSTI)

We present a collection of signatures for physics beyond the standard model that need to be explored at the LHC. The signatures are organized according to the experimental objects that appear in the final state, and in particular the number of high p{sub T} leptons. Our report, which includes brief experimental and theoretical reviews as well as original results, summarizes the activities of the 'New Physics' working group for the 'Physics at TeV Colliders' workshop (Les Houches, France, 11-29 June, 2007).

Brooijmans, Gustaaf H.; /Columbia U.; Delgado, A.; /Notre Dame U.; Dobrescu, Bogdan A.; /Fermilab; Grojean, C.; /CERN /Saclay, SPhT; Narain, Meenakshi; /Brown U.; Alwall, Johan; /SLAC; Azuelos, Georges; /Montreal U. /TRIUMF; Black, K.; /Harvard U.; Boos, E.; /SINP, Moscow; Bose, Tulika; /Brown U.; Bunichev, V.; /SINP, Moscow; Chivukula, R.S.; /Michigan State U.; Contino, R.; /CERN; Djouadi, A.; /Louis Pasteur U., Strasbourg I /Orsay, LAL; Dudko, Lev V.; /Durham U.; Ferland, J.; /Montreal U.; Gershtein, Yuri S.; /Florida State U.; Gigg, M.; /Durham U.; Gonzalez de la Hoz, S.; /Valencia U., IFIC; Herquet, M.; /Louvain U.; Hirn, J.; /Yale U. /Brown U. /Boston U. /Annecy, LAPTH /INFN, Turin /Valencia U., IFIC /Yale U. /Arizona U. /Louis Pasteur U., Strasbourg I /Orsay, LAL /KEK, Tsukuba /Moscow State U. /Lisbon, LIFEP /CERN /Durham U. /Valencia U., IFIC /Sao Paulo, IFT /Fermilab /Zurich, ETH /Boston U. /DESY /CERN /Saclay, SPhT /Durham U. /Cambridge U. /Michigan State U. /Louis Pasteur U., Strasbourg I /Orsay, LAL /Annecy, LAPTH /Fermilab /CERN /Arizona U. /Northwestern U. /Argonne /Kyoto U. /Valencia U., IFIC /UC, Berkeley /LBL, Berkeley

2011-12-05T23:59:59.000Z

182

Brilliant positron sources for CLIC and other collider projects  

E-Print Network [OSTI]

The CLIC (Compact Linear Collider), as future linear collider, requires an intense positron source. A brief history is given up to the present baseline configuration which assumes unpolarized beams. A conventional scheme, with a single tungsten target as source of e-e+ pairs, has been studied several years ago. But, in order to reduce the beam energy deposition on the e+ target converter, a double-target system has been studied and proposed as baseline for CLIC. With this ‘‘hybrid target’’, the positron production scheme is based on the channeling process. A 5 GeV electron beam impinges on a thin crystal tungsten target aligned along its axis, enhancing the photon production by channeling radiation. A large number of photons are sent to a thick amorphous tungsten target, generating large number of e-e+ pairs, while the charged particles are bent away, reducing the deposited energy and the PEDD (Peak Energy Deposition Density). The targets parameters are optimized for the positron production. Polarize...

Rinolfi, Louis; Dadoun, Olivier; Kamitani, Takuya; Strakhovenko, Vladimir; Variola, Alessandro

2013-01-01T23:59:59.000Z

183

Performance of ?q-lepton reconstruction and identification in CMS  

SciTech Connect (OSTI)

The performance of tau-lepton reconstruction and identification algorithms is studied using a data sample of proton-proton collisions at sqrt(s)=7 TeV, corresponding to an integrated luminosity of 36 inverse picobarns collected with the CMS detector at the LHC. The tau leptons that decay into one or three charged hadrons, zero or more short-lived neutral hadrons, and a neutrino are identified using final-state particles reconstructed in the CMS tracker and electromagnetic calorimeter. The reconstruction efficiency of the algorithms is measured using tau leptons produced in Z-boson decays. The tau-lepton misidentification rates for jets and electrons are determined.

Chatrchyan, Serguei; et al.

2012-01-01T23:59:59.000Z

184

Search for pair production of scalar top quarks decaying to a tau lepton and a b quark in 1.96 TeV ppbar collisions  

SciTech Connect (OSTI)

I present the results of a search for pair production of scalar top quarks ({tilde t}{sub 1}) in an R-parity violating supersymmetric scenario using 322 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected by the upgraded Collider Detector at Fermilab. I assume each {tilde t}{sub 1} decays into a {tau} lepton and a b quark, with branching ratio {beta}, and search for final states containing either an electron or a muon from a leptonic {tau} decay, a hadronically decaying {tau} lepton, and two or more jets. Two candidate events pass my final selection criteria, consistent with the expectation from standard model processes. I present upper limits on the cross section times branching ratio squared {sigma}({tilde t}{sub 1}{bar {tilde t}}{sub 1}) x {beta}{sup 2} as a function of the stop mass m({tilde t}{sub 1}). Assuming {beta} = 1, I set a 95% confidence level limit m({tilde t}{sub 1}) > 153 GeV=c{sup 2}. These limits are also fully applicable to the case of a pair produced third generation scalar leptoquark that decays into a {tau} lepton and a b quark.

Khotilovich, Vadim, G.; /Texas A-M

2008-05-01T23:59:59.000Z

185

Comparison of photon colliders based on e-e- and e+e- beams  

E-Print Network [OSTI]

At photon colliders gamma-gamma, gamma-electron high energy photons are produced by Compton scattering of laser light off the high energy electrons (or positrons) at a linear collider. At first sight, photon colliders based on e-e- or e+e- primary beams have similar properties and therefore for convenience one can use e+e- beams both for e+e- and gamma-gamma modes of operation. Below we compare these options and show that e-e- beams are much better (mandatory) because in the e+e- case low energy background gamma-gamma to hadrons is much higher and e+e- annihilation reactions present a very serious background for gamma-gamma processes.

V. I. Telnov

2005-07-15T23:59:59.000Z

186

Superconducting solenoids for the Muon collider  

E-Print Network [OSTI]

muon collider has superconducting solenoids as an integralLBNL-44303 SCMAG-690 Superconducting Solenoids for the MuonDE-AC03-76SFOOO98. J Superconducting Solenoids for the Muon

Green, M.A.

2011-01-01T23:59:59.000Z

187

PHYSICS AT HIGH LUMINOSITY MUON COLLIDERS AND A FACILITY OVERVIEW.  

SciTech Connect (OSTI)

Physics potentials at future colliders including high luminosity {mu}{sup +}{mu}{sup -} colliders are discussed. Luminosity requirement, estimates for Muon collider energies of interest (0.1 TeV to 100 TeV) are calculated. Schematics and an overview of Muon Collider facility concept are also included.

PARSA,Z.

2001-07-01T23:59:59.000Z

188

First search for CP violation in tau lepton decay  

E-Print Network [OSTI]

We have performed the first search for CP violation in tau lepton decay. CP violation in lepton decay does not occur in the minimal standard model but can occur in extensions such as the multi-Higgs doublet model. It appears as a characteristic...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

1998-11-01T23:59:59.000Z

189

Search for events with leptonic jets and missing transverse energy in $\\mathbf{p\\bar{p}}$ collisions at $\\mathbf{\\sqrt{s}=1.96}$ TeV  

SciTech Connect (OSTI)

We present the first search for pair production of isolated jets of charged leptons in association with a large imbalance in transverse energy in p{bar p} collisions using 5.8 fb{sup -1} of integrated luminosity collected by the D0 detector at the Fermilab Tevatron Collider. No excess is observed above Standard Model background, and the result is used to set upper limits on the production cross section of pairs of supersymmetric chargino and neutralino particles as a function of 'dark-photon' mass, where the dark photon is produced in the decay of the lightest supersymmetric particle.

Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Abolins, Maris A.; /Michigan State U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Alves, Gilvan Augusto; /Rio de Janeiro, CBPF /Nijmegen U.

2010-08-01T23:59:59.000Z

190

Opportunities and requirements for experimentation at high energy e/sup +/e/sup /minus// collider  

SciTech Connect (OSTI)

Over the past fifteen years of high-energy physics, electron-positron annihilation has been the most productive of all reactions probing the fundamental interactions. The e/sup +/e/sup /minus// annihilation process is unique in offering at the same time copious production of novel particles, low backgrounds from more conventional physics, and the most efficient use of the energy which an accelerator provides. These features have allowed the detailed characterization of the charm and bottom quark-antiquark systems and the unambiguous discovery of gluon jets---the crucial ingredients in the establishment of Quantum Chromodynamics as the correct theory of the strong interactions---as well as the discovery of the tau lepton and confirmation of the weak and electromagnetic properties of all the quarks and leptons at high energy. Over the past few years, experiments will begin at SLC and LEP, and we anticipate new discoveries from the detailed study of the Z/sup 0/ resonance. It is time, then to begin to think out how one might continue this mode experimentation to still higher energies. This document is the report of a committee convened by the Director of SLAC, Burton Richter, to set out the major physics goals of an e/sup +/e/sup /minus// collider in the energy range 600 GeV-1 TeV, corresponding to the next feasible step in accelerator technology. The committee was charged with the task of outlining the main experiments that such a collider might carry out and the requirements which those experiments place on the accelerator design. 106 refs., 105 figs., 13 tabs.

Ahn, C.; Baltay, C.; Barklow, T.L.; Burchat, P.R.; Burke, D.L.; Cooper, A.R.; Dib, C.; Feldman, G.J.; Gunion, J.F.; Haber, H.E.

1988-05-01T23:59:59.000Z

191

Isolated leptons in events with missing transverse momentum and the search for single top production  

E-Print Network [OSTI]

Calorimeter · Optimised for precision measure- ment of the scattered lepton ZEUS · Depleted Uranium

192

The Search for Higgs particles at high-energy colliders: Past, Present and Future  

E-Print Network [OSTI]

I briefly review the Higgs sector in the Standard Model and its minimal Supersymmetric extension, the MSSM. After summarizing the properties of the Higgs bosons and the present experimental constraints, I will discuss the prospects for discovering these particle at the upgraded Tevatron, the LHC and a high-energy $e^+e^-$ linear collider. The possibility of studying the properties of the Higgs particles will be then summarized.

A. Djouadi

2002-05-22T23:59:59.000Z

193

The Quirky Collider Signals of Folded Supersymmetry  

SciTech Connect (OSTI)

We investigate the collider signals associated with scalar quirks ('squirks') in folded supersymmetric models. As opposed to regular superpartners in supersymmetric models these particles are uncolored, but are instead charged under a new confining group, leading to radically different collider signals. Due to the new strong dynamics, squirks that are pair produced do not hadronize separately, but rather form a highly excited bound state. The excited 'squirkonium' loses energy to radiation before annihilating back into Standard Model particles. We calculate the branching fractions into various channels for this process, which is prompt on collider time-scales. The most promising annihilation channel for discovery is W+photon which dominates for squirkonium near its ground state. We demonstrate the feasibility of the LHC search, showing that the mass peak is visible above the SM continuum background and estimate the discovery reach.

Burdman, Gustavo; Chacko, Z.; Goh, Hock-Seng; Harnik, Roni; Krenke, Christopher A.

2008-08-01T23:59:59.000Z

194

Beam instrumentation for the Tevatron Collider  

SciTech Connect (OSTI)

The Tevatron in Collider Run II (2001-present) is operating with six times more bunches and many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for future colliders.

Moore, Ronald S.; Jansson, Andreas; Shiltsev, Vladimir; /Fermilab

2009-10-01T23:59:59.000Z

195

Top quark studies at hadron colliders  

SciTech Connect (OSTI)

The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag b quark jets in candidate events. The most recent measurements of top quark properties by the CDF and DO Collaborations are reviewed, including the top quark cross section, mass, branching fractions, and production properties. Future top quark studies at hadron colliders are discussed, and predictions for event yields and uncertainties in the measurements of top quark properties are presented.

Sinervo, P.K. [Univ. of Toronto, Ontario (Canada)

1997-01-01T23:59:59.000Z

196

Measurement of the top quark mass in $p \\bar{p}$ collisions using events with two leptons  

SciTech Connect (OSTI)

We present a measurement of the top quark mass (m{sub t}) in p{bar p} collisions at {radical}s = 1.96 TeV using t{bar t} events with two leptons (ee, e{mu} or {mu}{mu}) in the final state in 4.3 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider. We analyze the kinematically underconstrained dilepton events by integrating over the neutrino rapidity distributions. We reduce the dominant systematic uncertainties from jet energy calibration using a correction obtained from t{bar t} {yields} {ell} + jets events. We also correct jets in simulated events to replicate the quark flavor dependence of the jet response in data. In combination with our previous analysis, we measure m{sub t} = 174.0 {+-} 2.4(stat) {+-} 1.4(syst) GeV.

Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Aoki, Masato; /Fermilab; Askew, Andrew Warren; /Florida State U. /Stockholm U.

2012-01-01T23:59:59.000Z

197

Measurement of the Topological Branching Fractions of the ? Lepton  

E-Print Network [OSTI]

We report new and precise measurements of the decay branching fractions of the ? lepton to one and three charged particles. The data, corresponding to an integrated luminosity of 176 pb(?1), were collected by the high ...

Baringer, Philip S.

1985-08-05T23:59:59.000Z

198

Leptonic $D_s$ decays at $B$-factories  

E-Print Network [OSTI]

We review recent measurements of leptonic $D_s$-meson decays performed by Belle and BaBar collaborations. Described measurements enable experimental extraction of the $D_s$-meson decay constant which can be compared with lattice QCD calculations.

A. Zupanc

2013-01-30T23:59:59.000Z

199

Lepton flavor violation decays with the fourth generation neutrino  

E-Print Network [OSTI]

We investigate the lepton flavor violation decays, $\\tau \\to \\mu\\gamma$, $\\tau \\to e\\gamma$ and $\\mu \\to e\\gamma$, in the framwork of a squential fourth generation model with a heavy fourth neutrino, $\

Wu-Jun Huo; Tai-Fu Feng

2002-03-22T23:59:59.000Z

200

Non-thermal high-energy emission from colliding winds of massive stars  

E-Print Network [OSTI]

Colliding winds of massive star binary systems are considered as potential sites of non-thermal high-energy photon production. This is motivated merely by the detection of synchrotron radio emission from the expected colliding wind location. Here we investigate the properties of high-energy photon production in colliding winds of long-period WR+OB-systems. We found that in the dominating leptonic radiation process anisotropy and Klein-Nishina effects may yield spectral and variability signatures in the gamma-ray domain at or above the sensitivity of current or upcoming gamma-ray telescopes. Analytical formulae for the steady-state particle spectra are derived assuming diffusive particle acceleration out of a pool of thermal wind particles, and taking into account adiabatic and all relevant radiative losses. For the first time we include their advection/convection in the wind collision zone, and distinguish two regions within this extended region: the acceleration region where spatial diffusion is superior to convective/advective motion, and the convection region defined by the convection time shorter than the diffusion time scale. The calculation of the Inverse Compton radiation uses the full Klein-Nishina cross section, and takes into account the anisotropic nature of the scattering process. This leads to orbital flux variations by up to several orders of magnitude which may, however, be blurred by the geometry of the system. The calculations are applied to the typical WR+OB-systems WR 140 and WR 147 to yield predictions of their expected spectral and temporal characteristica and to evaluate chances to detect high-energy emission with the current and upcoming gamma-ray experiments. (abridged)

A. Reimer; M. Pohl; O. Reimer

2005-10-25T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

PHYSICS WITH AND PHYSICS OF COLLIDING ELECTRON BEAMS  

E-Print Network [OSTI]

contributed so much to the physics of colliding beams, theyto reap so little from the physics with colliding beams.Conference on High-Energy Physics, Vienna" September 1968 (

Pellegrini, Claudio

2008-01-01T23:59:59.000Z

202

Future Colliders Beyond the Standard Model  

E-Print Network [OSTI]

. Of course, the lesson of high energy physics has been that higher energies have generally revealed new that the full exploration of the Standard Model was likely to require a very high energy hadron collider important, it is not possible to postpone indefinitely new physics associated with the Higgs boson. To see

Murayama, Hitoshi

203

Electron Ion Collider: The Next QCD Frontier  

E-Print Network [OSTI]

Electron Ion Collider: The Next QCD Frontier Executive Summary Understanding the glue that binds us . . . . . . . . . . . . . . . . . . . . 7 1.2.3 Physics Possibilities at the Intensity Frontier . . . . . . . . . . . . . 10 1 charge. This causes the gluons to interact with each other, generating nearly all the mass of the nucleon

Homes, Christopher C.

204

Phenomenology of the minimal B ? L Model: the Higgs sector at the Large Hadron Collider and future linear colliders.  

E-Print Network [OSTI]

??This thesis is devoted to the study of the phenomenology of the Higgs sector of the minimal B ?L extension of the Standard Model at… (more)

Pruna, Giovanni Marco

2011-01-01T23:59:59.000Z

205

Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider  

E-Print Network [OSTI]

Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The longrange beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing acrossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit, ...

Sun, Y P; Barranco, J; Tomàs, R; Weiler, T; Zimmermann, F; Calaga, R; Morita, A

2009-01-01T23:59:59.000Z

206

Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider  

E-Print Network [OSTI]

Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The long-range beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing a crossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit...

Sun, Y P; Barranco, J; Tomás, R; Weiler, T; Zimmermann, F; Calaga, R; Morita, A

2009-01-01T23:59:59.000Z

207

Future high energy colliders symposium. Summary report  

SciTech Connect (OSTI)

A `Future High Energy Colliders` Symposium was held October 21-25, 1996 at the Institute for Theoretical Physics (ITP) in Santa Barbara. This was one of the 3 symposia hosted by the ITP and supported by its sponsor, the National Science Foundation, as part of a 5 month program on `New Ideas for Particle Accelerators`. The long term program and symposia were organized and coordinated by Dr. Zohreh Parsa of Brookhaven National Laboratory/ITP. The purpose of the symposium was to discuss the future direction of high energy physics by bringing together leaders from the theoretical, experimental and accelerator physics communities. Their talks provided personal perspectives on the physics objectives and the technology demands of future high energy colliders. Collectively, they formed a vision for where the field should be heading and how it might best reach its objectives.

Parsa, Z. [Univ. of California, Santa Barbara, CA (United States). Institute for Theoretical Physics]|[Brookhaven National Lab., Upton, CA (United States)

1996-12-31T23:59:59.000Z

208

Fermilab collider run 1b accelerator performance  

SciTech Connect (OSTI)

This report summarizes the performance of Run 1b as of the end of July 1995. This run is the conclusion of Fermilab Collider Run 1, which consists of Run 1a (May 1992 - May 1993) and Run 1b (January 1994 - February 1996). Run 1b is characterized by being the first with the new 400 MeV Linac. At this time the run is not complete. Colliding beam physics is scheduled to resume after the summer 1995 shut down and continue until mid-February 1996. All of the operation to date is at a Tevatron energy of 900 GeV. This report emphasizes performance numbers and the various improvements made to systems to achieve this performance. It will only discuss the underlying physics to a limited extent. The report is divided into sections on: run statistics, I&C issues, proton source performance, antiproton source performance, main ring performance, Tevatron performance, and a summary.

Bharadwaj, V.; Halling, M.; Lucas, P.; McCrory, E.; Mishra, S.; Pruss, S.; Werkema, S.

1996-04-01T23:59:59.000Z

209

The Design of a Large Booster Ring for the Medium Energy Electron-Ion Collider at Jlab  

SciTech Connect (OSTI)

In this paper, we present the current design of the large booster ring for the Medium energy Electron-Ion Collider at Jefferson Lab. The booster ring takes 3 GeV protons or ions of equivalent rigidity from a pre-booster ring, and accelerates them to 20 GeV for protons or equivalent energy for light to heavy ions before sending them to the ion collider ring. The present design calls for a figure-8 shape of the ring for superior preservation of ion polarization. The ring is made of warm magnets and shares a tunnel with the two collider rings. Acceleration is achieved by warm RF systems. The linear optics has been designed with the transition energy above the highest beam energy in the ring so crossing of transition energy will be avoided. Preliminary beam dynamics studies including chromaticity compensation are presented in this paper.

Edward Nissen, Todd Satogata, Yuhong Zhang

2012-07-01T23:59:59.000Z

210

Really large hadron collider working group summary  

SciTech Connect (OSTI)

A summary is presented of preliminary studies of three 100 TeV center-of-mass hadron colliders made with magnets of different field strengths, 1.8T, 9.5T and 12.6T. Descriptions of the machines, and some of the major and most challenging subsystems, are presented, along with parameter lists and the major issues for future study.

Dugan, G. [Cornell Univ., Ithaca, NY (United States); Limon, P. [Fermilab, Batavia, IL (United States); Syphers, M. [Brookhaven National Lab., Upton, NY (United States)

1996-12-01T23:59:59.000Z

211

1987 DOE review: First collider run operation  

SciTech Connect (OSTI)

This review covers the operations of the first run of the 1.8 TeV superconducting super collider. The papers enclosed cover: PBAR source status, fixed target operation, Tevatron cryogenic reliability and capacity upgrade, Tevatron Energy upgrade progress and plans, status of the D0 low beta insertion, 1.8 K and 4.7 K refrigeration for low-..beta.. quadrupoles, progress and plans for the LINAC and booster, near term and long term and long term performance improvements.

Childress, S.; Crawford, J.; Dugan, G.; Edwards, H.; Finley, D.A.; Fowler, W.B.; Harrison, M.; Holmes, S.; Makara, J.N.; Malamud, E.

1987-05-01T23:59:59.000Z

212

Interpenetration and stagnation in colliding laser plasmas  

SciTech Connect (OSTI)

We have investigated plasma stagnation and interaction effects in colliding laser-produced plasmas. For generating colliding plasmas, two split laser beams were line-focused onto a hemi-circular target and the seed plasmas so produced were allowed to expand in mutually orthogonal directions. This experimental setup forced the expanding seed plasmas to come to a focus at the center of the chamber. The interpenetration and stagnation of plasmas of candidate fusion wall materials, viz., carbon and tungsten, and other materials, viz., aluminum, and molybdenum were investigated in this study. Fast-gated imaging, Faraday cup ion analysis, and optical emission spectroscopy were used for diagnosing seed and colliding plasma plumes. Our results show that high-Z target (W, Mo) plasma ions interpenetrate each other, while low-Z (C, Al) plasmas stagnate at the collision plane. For carbon seed plasmas, an intense stagnation was observed resulting in longer plasma lifetime; in addition, the stagnation layer was found to be rich with C{sub 2} dimers.

Al-Shboul, K. F. [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States) [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Department of Nuclear Engineering, Jordan University of Science and Technology, Irbid 22110 (Jordan); Harilal, S. S., E-mail: hari@purdue.edu; Hassan, S. M.; Hassanein, A. [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)] [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Costello, J. T. [School of Physical Sciences and NCPST, Dublin City University, Dublin 9 (Ireland)] [School of Physical Sciences and NCPST, Dublin City University, Dublin 9 (Ireland); Yabuuchi, T.; Tanaka, K. A. [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 5650871 (Japan)] [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 5650871 (Japan); Hirooka, Y. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu (Japan)] [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu (Japan)

2014-01-15T23:59:59.000Z

213

Nuclear PDF for neutrino and charged lepton data  

E-Print Network [OSTI]

Neutrino Deep Inelastic Scattering on nuclei is an essential process to constrain the strange quark parton distribution functions in the proton. The critical component on the way to using the neutrino DIS data in a proton PDF analysis is understanding the nuclear effects in parton distribution functions. We parametrize these effects by nuclear parton distribution functions. Here we compare results from two analysis of NPDF both done at next-to-leading order in QCD. The first uses neutral current charged-lepton lA Deeply Inelastic Scattering and Drell-Yan data for several nuclear targets and the second uses neutrino-nucleon DIS data. We compare the nuclear corrections factors F_2^Fe/F_2^D for the charged-lepton data with other results from the literature. In particular, we compare and contrast fits based upon the charged-lepton DIS data with those using neutrino-nucleon DIS data.

K. Kovarik

2010-12-13T23:59:59.000Z

214

Neutrino oscillation experiments and limits on lepton-number and lepton-flavor violating processes  

E-Print Network [OSTI]

Using a three neutrino framework we investigate bounds for the effective Majorana neutrino mass matrix. The mass measured in neutrinoless double beta decay is its (11) element. Lepton-number and -flavor violating processes sensitive to each element are considered and limits on branching ratios or cross sections are given. Those processes include $\\mu^- e^+$ conversion, $K^+ \\to \\pi^- \\mu^+ \\mu^+$ or recently proposed high-energy scattering processes at HERA. Including all possible mass schemes, the three solar solutions and other allowed possibilities, there is a total of 80 mass matrices. The obtained indirect limits are up to 14 orders of magnitude more stringent than direct ones. It is investigated how neutrinoless double beta decay may judge between different mass and mixing schemes as well as solar solutions. Prospects for detecting processes depending on elements of the mass matrix are also discussed.

W. Rodejohann

2000-06-19T23:59:59.000Z

215

Neutrinoless Double Beta Decay and Lepton Flavor Violation  

E-Print Network [OSTI]

We point out that extensions of the Standard Model with low scale (~TeV) lepton number violation (LNV) generally lead to a pattern of lepton flavor violation (LFV) experimentally distinguishable from the one implied by models with GUT scale LNV. As a consequence, muon LFV processes provide a powerful diagnostic tool to determine whether or not the effective neutrino mass can be deduced from the rate of neutrinoless double beta decay. We discuss the role of \\mu -> e \\gamma and \\mu -> e conversion in nuclei, which will be studied with high sensitivity in forthcoming experiments.

V. Cirigliano; A. Kurylov; M. J. Ramsey-Musolf; P. Vogel

2004-06-17T23:59:59.000Z

216

Relating quarks and leptons with the T7 flavour group  

E-Print Network [OSTI]

In this letter we present a model for quarks and leptons based on T7 as flavour symmetry, predicting a canonical mass relation between charged leptons and down-type quarks proposed earlier. Neutrino masses are generated through a Type-I seesaw mechanism, with predicted correlations between the atmospheric mixing angle and neutrino masses. Compatibility with oscillation results lead to lower bounds for the lightest neutrino mass as well as for the neutrinoless double beta decay rates, even for normal neutrino mass hierarchy.

Bonilla, Cesar; Peinado, Eduardo; Valle, Jose W F

2014-01-01T23:59:59.000Z

217

THE STATUS OF HEAVY-LEPTON SEARCHES*+ Martin L. Per1 Stanford Linear Accelerator Center  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystallineForeign Object DamageSystemsU.S. TALKS1

218

SSC collider dipole magnet end mechanical design  

SciTech Connect (OSTI)

This paper describes the mechanical design of the ends of Superconducting Super Collider dipole magnets to be constructed and tested at Fermilab. Coil end clamps, end yoke configuration, and end plate design are discussed. Loading of the end plate by axial Lorentz forces is discussed. Relevant data from 40 mm and 50 mm aperture model dipole magnets built and tested at Fermilab are presented. In particular, the apparent influence of end clamp design on the quench behavior of model SSC dipoles is described. 8 refs., 3 figs.

Delchamps, S.W.; Bossert, R.C.; Carson, J.; Ewald, K.; Fulton, H.; Kerby, J.; Koska, W.; Strait, J.; Wake, S.M. (Fermi National Accelerator Lab., Batavia, IL (USA)); Leung, K.K. (Superconducting Super Collider Lab., Dallas, TX (USA))

1991-05-01T23:59:59.000Z

219

B Physics Theory for Hadron Colliders  

E-Print Network [OSTI]

A short overview of theoretical methods for B physics at hadron colliders is presented. The main emphasis is on the theory of two-body hadronic B decays, which provide a rich field of investigation in particular for the Tevatron and the LHC. The subject holds both interesting theoretical challenges as well as many opportunities for flavor studies and new physics tests. A brief review of the current status and recent developments is given. A few additional topics in B physics are also mentioned.

G. Buchalla

2008-09-03T23:59:59.000Z

220

Future high energy colliders. Formal report  

SciTech Connect (OSTI)

This Report includes copies of transparencies and notes from the presentations made at the Symposium on Future High Energy Colliders, October 21-25, 1996 at the Institute for Theoretical Physics, University of California, Santa Barbara California, that was made available by the authors. Editing, reduction and changes to the authors contributions were made only to fulfill the printing and publication requirements. We would like to take this opportunity and thank the speakers for their informative presentations and for providing copies of their transparencies and notes for inclusion in this Report.

Parsa, Z. [ed.] [ed.

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

QCD Factorization for heavy quarkonium production at collider energies  

E-Print Network [OSTI]

In this talk, I briefly review several models of the heavy quarkonium production at collider energies, and discuss the status of QCD factorization for these production models.

Jian-Wei Qiu

2006-10-31T23:59:59.000Z

222

Primary Versus Secondary Leptons in the EGRET SNR's  

E-Print Network [OSTI]

The EGRET supernova remnants (SNR's) are all expanding into nearby dense molecular clouds, powering a shock at the interface where protons and electrons accelerate to relativistic energies. A viable mechanism for the emission of gamma$-rays in these sources is the decay of neutral pions created in collisions between the relativistic hadrons and protons in the ambient medium. But neutral pion decay alone cannot reproduce the whole high-energy spectrum, particularly below 100 MeV. A pion-decay scenario thus requires a lepton population to "fill in" the lower part of the spectrum via bremsstrahlung emission. This population, however, is constrained by the SNR radio spectrum. Taking our cue from the behavior of Sgr A East, an energetic EGRET SNR at the Galactic center, we here examine the role played in these sources by secondary leptons--electrons and positrons produced in proton-proton scattering events and the ensuing particle cascades. We show that while secondary leptons cannot account for the gamma-rays below 100 MeV, they can account for the hard radio spectra observed from the EGRET SNR's. Thus, it appears that both primary and secondary leptons may be important contributors to the overall broadband emission from these sources, but if so, must radiate most of their energy in different parts of the SNR-cloud environment. We show that shock acceleration in dense cores being overtaken by the expanding SNR shell can naturally lead to such a scenario.

Marco Fatuzzo; Fulvio Melia

2004-12-17T23:59:59.000Z

223

A Lepton Universality Test at CERN NA62 Experiment  

E-Print Network [OSTI]

The NA62 experiment at CERN collected a large sample of K+ --> enu decays during a dedicated run in 2007, aiming at a precise test of lepton universality by measurement of the helicity suppressed ratio RK = BR(K+ --> enu)/BR(K+ --> munu). A preliminary result of the analysis of a partial data sample of 51089 K+ --> enu candidates is presented.

Evgueni Goudzovski

2010-05-07T23:59:59.000Z

224

Tau decays into three charged leptons and two neutrinos  

E-Print Network [OSTI]

We search for the radiative leptonic tau decays tau --> ee(+) e(-)nu(tau)nu(e) and tau --> mu e(+)e(-)nu(tau)nu(mu) using 3.60 fb(-1) of data collected by the CLEO-II experiment at the Cornell Electron Storage Ring. We present a first observation...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Copty, N.; Davis, Robin E. P.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan

1996-04-01T23:59:59.000Z

225

Next-to-Leading Order Predictions for W + 3-Jet Distributions at Hadron Colliders  

SciTech Connect (OSTI)

We present next-to-leading order QCD predictions for a variety of distributions in W + 3-jet production at both the Tevatron and the Large Hadron Collider. We include all subprocesses and incorporate the decay of the W boson into leptons. Our results are in excellent agreement with existing Tevatron data and provide the first quantitatively precise next-to-leading order predictions for the LHC. We include all terms in an expansion in the number of colors, confirming that the specific leading-color approximation used in our previous study is accurate to within three percent. The dependence of the cross section on renormalization and factorization scales is reduced significantly with respect to a leading-order calculation. We study different dynamical scale choices, and find that the total transverse energy is significantly better than choices used in previous phenomenological studies. We compute the one-loop matrix elements using on-shell methods, as numerically implemented in the BlackHat code. The remaining parts of the calculation, including generation of the real-emission contributions and integration over phase space, are handled by the SHERPA package.

Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, L.J.; /SLAC; Febres Cordero, F.; /UCLA; Forde, D.; Gleisberg, T.; /SLAC; Ita, H.; /UCLA; Kosower, D.A.; /Saclay, SPhT; Maitre, D.; /Durham U.

2009-12-09T23:59:59.000Z

226

Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab  

SciTech Connect (OSTI)

Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectively utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the very beginning, the design studies at Jefferson Lab have focused on achieving high collider performance, particularly ultrahigh luminosities up to 10{sup 34} cm{sup -2}s{sup -1} per detector with large acceptance, while maintaining high polarization for both the electron and light-ion beams. These are the two key performance requirements of a future electron-ion collider facility as articulated by the NSAC Long Range Plan. In MEIC, a new ion complex is designed specifically to deliver ion beams that match the high bunch repetition and highly polarized electron beam from CEBAF. During the last two years, both development of the science case and optimization of the machine design point toward a medium-energy electron-ion collider as the topmost goal for Jefferson Lab. The MEIC, with relatively compact collider rings, can deliver a luminosity above 10{sup 34} cm{sup -2}s{sup -1} at a center-of-mass energy up to 65 GeV. It offers an electron energy up to 11 GeV, a proton energy up to 100 GeV, and corresponding energies per nucleon for heavy ions with the same magnetic rigidity. This design choice balances the scope of the science program, collider capabilities, accelerator technology innovation, and total project cost. An energy upgrade could be implemented in the future by adding two large collider rings housed in another large tunnel to push the center-of-mass energy up to or exceeding 140 GeV. After careful consideration of an alternative electron energy recovery linac on ion storage ring approach, a ring-ring collider scenario at high bunch repetition frequency was found to offer fully competitive performance while eliminating the uncertainties of challenging R&D on ampere-class polarized electron sources and many-pass energy-recovery linacs (ERLs). The essential new elements of an MEIC facility at Jefferson Lab are an electron storage ring and an entirely new, modern ion acceleration and storage complex. For the high-current electron collider ring, the upgraded 12 GeV CEBAF SRF linac will serve as a full-energy injector, and, if needed, provide top

Abeyratne, S; Ahmed, S; Barber, D; Bisognano, J; Bogacz, A; Castilla, A; Chevtsov, P; Corneliussen, S; Deconinck, W; Degtiarenko, P; Delayen, J; Derbenev, Ya; DeSilva, S; Douglas, D; Dudnikov, V; Ent, R; Erdelyi, B; Evtushenko, P; Fujii, Yu; Filatov, Yury; Gaskell, D; Geng, R; Guzey, V; Horn, T; Hutton, A; Hyde, C; Johnson, R; Kim, Y; Klein, F; Kondratenko, A; Kondratenko, M; Krafft, G; Li, R; Lin, F; Manikonda, S; Marhauser, F; McKeown, R; Morozov, V; Dadel-Turonski, P; Nissen, E; Ostroumov, P; Pivi, M; Pilat, F; Poelker, M; Prokudin, A; Rimmer, R; Satogata, T; Sayed, H; Spata, M; Sullivan, M; Tennant, C; Terzic, B; Tiefenback, M; Wang, M; Wang, S; Weiss, C; Yunn, B

2012-08-01T23:59:59.000Z

227

Energy Content of Colliding Plane Waves using Approximate Noether Symmetries  

E-Print Network [OSTI]

This paper is devoted to study the energy content of colliding plane waves using approximate Noether symmetries. For this purpose, we use approximate Lie symmetry method of Lagrangian for differential equations. We formulate the first-order perturbed Lagrangian for colliding plane electromagnetic and gravitational waves. It is shown that in both cases, there does not exist

M. Sharif; Saira Waheed

2011-09-19T23:59:59.000Z

228

Detectors for Neutrino Physics at the First Muon Collider  

E-Print Network [OSTI]

We consider possible detector designs for short-baseline neutrino experiments using neutrino beams produced at the First Muon Collider complex. The high fluxes available at the muon collider make possible high statistics deep-inelastic scattering neutrino experiments with a low-mass target. A design of a low-energy neutrino oscillation experiment on the ``tabletop'' scale is also discussed.

Deborah A. Harris; Kevin S. McFarland

1998-04-20T23:59:59.000Z

229

EIS-0138-S: Superconducting Super Collider, Supplemental, Waxahatchie, Texas  

Broader source: Energy.gov [DOE]

The U.S. Department of Energy developed this supplementary statement to analyze the environmental impacts of design modifications to the Superconducting Super Collider that were made following the publication of the Record of Decision that selected Ellis County, Texas, as the location of the laboratory facility. This statement supplements DOE/EIS-0138, Superconducting Super Collider.

230

Measurement of the B meson Lifetimes with the Collider Detector at Fermilab  

SciTech Connect (OSTI)

The lifetimes of the B{sup -}, B{sup 0} and B{sub s}{sup 0} mesons are measured using partially reconstructed semileptonic decays. Following semileptonic decay processes and their charge conjugates are used for this analysis: B{sup -}/B{sup 0} {yields} {ell}{sup -}{nu}D{sup 0}X; B{sup -}/B{sup 0} {yields} {ell}{sup -}{nu}D*{sup +}X; B{sub s}{sup 0} {yields} {ell}{sup -}{nu}D{sub s}{sup +}x, where {ell}{sup -} denotes either a muon or electron. The data are collected during 2002-2004 by the 8 GeV single lepton triggers in CDF Run II at the Fermilab Tevatron Collider. Corresponding integrated luminosity is about 260 and 360 pb{sup -1} used for the B{sup -}/B{sup 0} and B{sub s}{sup 0} lifetime analyses, respectively. With the single lepton triggers, events which contain a muon or electron with a transverse momentum greater than 8 GeV/c are selected. For these lepton candidates, further lepton identification cuts are applied to improve purity of the B semileptonic decay signal. After the lepton selection, three types of charm mesons associated with the lepton candidates are reconstructed. Following exclusive decay modes are used for the charm meson reconstruction: D{sup 0} {yields} K{sup -}{pi}{sup +}; D*{sup +} {yields} D{sup 0}{pi}{sub s}{sup +}, followed by D{sup 0} {yields} K{sup -}{pi}{sup +}; D{sub s}{sup +} {yields} {phi}{pi}{sup +}, followed by {phi} {yields} K{sup +}K{sup -}. Here {pi}{sub s}{sup +} denotes a slow pion from D*{sup +} decay. Species of the reconstructed charm meson identify the parent B meson species. However in the B{sup -}/B{sup 0} semileptonic decays, both mesons decay into the identical lepton + D{sup 0} final state. To solve this mixture of the B components in the D{sup 0} sample, they adopt the following method: First among the inclusive D{sup 0} sample, they look for the D*{sup +} {yields} D{sup 0} {pi}{sub s}{sup +} signal. The inclusive D{sup 0} sample is then split into the two samples of D{sup 0} mesons which are from the D*{sup +} meson and not from D*{sup +}. They use the fact that D*{sup +} sample is dominated by the B{sup 0} component, and the D{sup 0} sample after excluding the D*{sup +} events is dominated by the B{sup -} component. Fraction of remaining mixture of B{sup -}/B{sup 0} components in each sample is estimated using a Monte Carlo simulation. From the lepton + charm meson pairs, they measure the B meson decay lengths to extract the lifetimes. Since the B meson momentum, necessary to calculate the B meson decay time, is not fully reconstructed in semileptonic decays, the missing momentum is corrected using a Monte Carlo simulation during lifetime fits. Also, contributions of various kinds of backgrounds are considered and subtracted. As a result of the fit, the B meson lifetimes are measured to be c{tau}(B{sup -}) = 495.6 {+-} 8.6 {sub -12.8}{sup +13.3} {micro}m; c{tau}(B{sup 0}) = 441.5 {+-} 10.9 {+-} 17.0 {micro}m; c{tau}(B{sub s}{sup 0}) = 414.0 {+-} 16.6 {sub -13.8}{sup +15.6} {micro}m or {tau}(B{sup 0}) = 1.653 {+-} 0.029 {sub -0.031}{sup +0.033} ps; {tau}(B{sup 0}) = 1.473 {+-} 0.036 {+-} 0.054 ps; {tau}(B{sub s}{sup 0}) = 1.381 {+-} 0.055 {sub -0.046}{sup +0.052} ps, and the lifetime ratios to be {tau}(B{sup 0})/{tau}(B{sup 0}) = 1.123 {+-} 0.040 {sub -0.039}{sup +0.041}; {tau}(B{sub s}{sup 0})/{tau}(B{sup 0}) = 0.938 {+-} 0.044 {sub -0.046}{sup +0.049} where the first uncertainty is statistical and the second is systematic.

Uozumi, Satoru; /Tsukuba U.

2006-01-01T23:59:59.000Z

231

Evidence for $s$-channel Single-Top-Quark Production in Events with one Charged Lepton and two Jets at CDF  

E-Print Network [OSTI]

We report evidence for $s$-channel single-top-quark production in proton-antiproton collisions at center-of-mass energy $\\sqrt{s}= 1.96 \\mathrm{TeV}$ using a data set that corresponds to an integrated luminosity of $9.4 \\mathrm{fb}^{-1}$ collected by the Collider Detector at Fermilab. We select events consistent with the $s$-channel process including two jets and one leptonically decaying $W$ boson. The observed significance is $3.8$ standard deviations with respect to the background-only prediction. Assuming a top-quark mass of $172.5 \\mathrm{GeV}/c^2$, we measure the $s$-channel cross section to be $1.41^{+0.44}_{-0.42} \\mathrm{pb}$.

CDF Collaboration; T. Aaltonen; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; J. A. Appel; T. Arisawa; A. Artikov; J. Asaadi; W. Ashmanskas; B. Auerbach; A. Aurisano; F. Azfar; W. Badgett; T. Bae; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Barria; P. Bartos; M. Bauce; F. Bedeschi; S. Behari; G. Bellettini; J. Bellinger; D. Benjamin; A. Beretvas; A. Bhatti; K. R. Bland; B. Blumenfeld; A. Bocci; A. Bodek; D. Bortoletto; J. Boudreau; A. Boveia; L. Brigliadori; C. Bromberg; E. Brucken; J. Budagov; H. S. Budd; K. Burkett; G. Busetto; P. Bussey; P. Butti; A. Buzatu; A. Calamba; S. Camarda; M. Campanelli; F. Canelli; B. Carls; D. Carlsmith; R. Carosi; S. Carrillo; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; V. Cavaliere; M. Cavalli-Sforza; A. Cerri; L. Cerrito; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; K. Cho; D. Chokheli; A. Clark; C. Clarke; M. E. Convery; J. Conway; M. Corbo; M. Cordelli; C. A. Cox; D. J. Cox; M. Cremonesi; D. Cruz; J. Cuevas; R. Culbertson; N. d'Ascenzo; M. Datta; P. de Barbaro; L. Demortier; L. Marchese; M. Deninno; F. Devoto; M. D'Errico; A. Di Canto; B. Di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; M. Dorigo; A. Driutti; K. Ebina; R. Edgar; A. Elagin; R. Erbacher; S. Errede; B. Esham; S. Farrington; J. P. Fernández Ramos; R. Field; G. Flanagan; R. Forrest; M. Franklin; J. C. Freeman; H. Frisch; Y. Funakoshi; C. Galloni; A. F. Garfinkel; P. Garosi; H. Gerberich; E. Gerchtein; S. Giagu; V. Giakoumopoulou; K. Gibson; C. M. Ginsburg; N. Giokaris; P. Giromini; G. Giurgiu; V. Glagolev; D. Glenzinski; M. Gold; D. Goldin; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González López; I. Gorelov; A. T. Goshaw; K. Goulianos; E. Gramellini; S. Grinstein; C. Grosso-Pilcher; R. C. Group; J. Guimaraes da Costa; S. R. Hahn; J. Y. Han; F. Happacher; K. Hara; M. Hare; R. F. Harr; T. Harrington-Taber; K. Hatakeyama; C. Hays; J. Heinrich; M. Herndon; A. Hocker; Z. Hong; W. Hopkins; S. Hou; R. E. Hughes; U. Husemann; M. Hussein; J. Huston; G. Introzzi; M. Iori; A. Ivanov; E. James; D. Jang; B. Jayatilaka; E. J. Jeon; S. Jindariani; M. Jones; K. K. Joo; S. Y. Jun; T. R. Junk; M. Kambeitz; T. Kamon; P. E. Karchin; A. Kasmi; Y. Kato; W. Ketchum; J. Keung; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; Y. J. Kim; N. Kimura; M. Kirby; K. Knoepfel; K. Kondo; D. J. Kong; J. Konigsberg; A. V. Kotwal; M. Kreps; J. Kroll; M. Kruse; T. Kuhr; M. Kurata; A. T. Laasanen; S. Lammel; M. Lancaster; K. Lannon; G. Latino; H. S. Lee; J. S. Lee; S. Leo; S. Leone; J. D. Lewis; A. Limosani; E. Lipeles; A. Lister; H. Liu; Q. Liu; T. Liu; S. Lockwitz; A. Loginov; A. Lucà; D. Lucchesi; J. Lueck; P. Lujan; P. Lukens; G. Lungu; J. Lys; R. Lysak; R. Madrak; P. Maestro; S. Malik; G. Manca; A. Manousakis-Katsikakis; F. Margaroli; P. Marino; M. Martínez; K. Matera; M. E. Mattson; A. Mazzacane; P. Mazzanti; R. McNulty; A. Mehta; P. Mehtala; C. Mesropian; T. Miao; D. Mietlicki; A. Mitra; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. J. Morello; A. Mukherjee; Th. Muller; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; J. Naganoma; I. Nakano; A. Napier; J. Nett; C. Neu; T. Nigmanov; L. Nodulman; S. Y. Noh; O. Norniella; L. Oakes; S. H. Oh; Y. D. Oh; I. Oksuzian; T. Okusawa; R. Orava; L. Ortolan; C. Pagliarone; E. Palencia; P. Palni; V. Papadimitriou; W. Parker; G. Pauletta; M. Paulini; C. Paus; T. J. Phillips; G. Piacentino; E. Pianori; J. Pilot; K. Pitts; C. Plager; L. Pondrom; S. Poprocki; K. Potamianos; F. Prokoshin; A. Pranko; F. Ptohos; G. Punzi; N. Ranjan; I. Redondo Fernández; P. Renton; M. Rescigno; F. Rimondi; L. Ristori; A. Robson; T. Rodriguez; S. Rolli; M. Ronzani; R. Roser; J. L. Rosner; F. Ruffini; A. Ruiz; J. Russ; V. Rusu; W. K. Sakumoto; Y. Sakurai; L. Santi; K. Sato; V. Saveliev; A. Savoy-Navarro; P. Schlabach; E. E. Schmidt; T. Schwarz; L. Scodellaro; F. Scuri; S. Seidel; Y. Seiya; A. Semenov; F. Sforza; S. Z. Shalhout; T. Shears; P. F. Shepard; M. Shimojima; M. Shochet; I. Shreyber-Tecker; A. Simonenko; K. Sliwa; J. R. Smith; F. D. Snider; V. Sorin; H. Song; M. Stancari; R. St. Denis; D. Stentz; J. Strologas; Y. Sudo; A. Sukhanov; I. Suslov; K. Takemasa; Y. Takeuchi; J. Tang; M. Tecchio; P. K. Teng; J. Thom; E. Thomson; V. Thukral; D. Toback; S. Tokar; K. Tollefson; T. Tomura; D. Tonelli; S. Torre; D. Torretta; P. Totaro; M. Trovato; F. Ukegawa; S. Uozumi; F. Vázquez; G. Velev; C. Vellidis; C. Vernieri; M. Vidal; R. Vilar; J. Vizán; M. Vogel; G. Volpi; P. Wagner; R. Wallny; S. M. Wang; D. Waters; W. C. Wester III; D. Whiteson; A. B. Wicklund; S. Wilbur; H. H. Williams; J. S. Wilson; P. Wilson; B. L. Winer; P. Wittich; S. Wolbers; H. Wolfe; T. Wright; X. Wu; Z. Wu; K. Yamamoto; D. Yamato; T. Yang; U. K. Yang; Y. C. Yang; W. -M. Yao; G. P. Yeh; K. Yi; J. Yoh; K. Yorita; T. Yoshida; G. B. Yu

2014-04-21T23:59:59.000Z

232

Search for microscopic black holes and string balls in final states with leptons and jets with the ATLAS detector at sqrt(s) = 8 TeV  

E-Print Network [OSTI]

A search for an excess of events with multiple high transverse momentum objects including charged leptons and jets is presented, using 20.3 fb^-1 of proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2012 at a centre-of-mass energy of sqrt(s) = 8 TeV. No excess of events beyond Standard Model expectations is observed. Using extra-dimensional models for black hole and string ball production and decay, exclusion contours are determined as a function of the mass threshold for production and the fundamental gravity scale for two, four and six extra dimensions. For six extra dimensions, mass thresholds of 4.8-6.2 TeV are excluded at 95% confidence level, depending on the fundamental gravity scale and model assumptions. Upper limits on the fiducial cross-sections for non-Standard Model production of these final states are set.

ATLAS Collaboration

2014-09-08T23:59:59.000Z

233

Collider Phenomenology with Split-UED  

SciTech Connect (OSTI)

We investigate the collider implications of Split Universal Extra Dimensions. The non-vanishing fermion mass in the bulk, which is consistent with the KK-parity, largely modifies the phenomenology of Minimal Universal Extra Dimensions. We scrutinize the behavior of couplings and study the discovery reach of the Tevatron and the LHC for level-2 Kaluza-Klein modes in the dilepton channel, which would indicates the presence of the extra dimensions. Observation of large event rates for dilepton resonances can result from a nontrivial fermion mass profile along the extra dimensions, which, in turn, may corroborate extra dimensional explanation for the observation of the positron excess in cosmic rays. The Minimal Universal Extra Dimensions scenario has received great attention. Recently non-vanishing bulk fermion masses have been introduced without spoiling the virtue of KK-parity. The fermion profiles are no longer simple sine/cosine functions and depend upon the specific values of bulk parameters. The profiles of fermions are split along the extra dimensions while the wave functions of the bosons remain the same as in UED. A simple introduction of a KK-parity conserving bulk fermion mass has significant influences on collider aspects as well as astrophysical implications of UED. For instance, the DM annihilation fraction into certain SM fermion pairs is either enhanced or reduced (compared to the MUED case) so that one can perhaps explain the PAMELA positron excess while suppressing the anti-proton flux. In this paper, we have concentrated on collider phenomenology of Split Universal Extra Dimensions. We have revisited the KK decomposition in detail and analyzed wave function overlaps to compute relevant couplings for collider studies. We have discussed general collider implication for level-1 KK modes and level-2 KK with non-zero bulk mass and have computed LHC reach for the EW level-2 KK bosons, {gamma}{sub 2} and Z{sub 2}, in the dilepton channel. The LHC should able to cover the large parameter space (up to M{sub V{sub 2}} {approx} 1.5 TeV for {mu}L {ge} 1) even with early data assuming {approx}100 pb{sup -1} or less. The existence of double resonances is one essential feature arising from extra dimensional models. Whether or not one can see double resonances depends both on how degenerate the two resonances are and on the mass resolution of the detector. The very high P{sub T} from the decay makes resolution in dimuon channel worse than in dielectron final state. This is because one can reconstruct electron from ECAL but muon momentum reconstruction relies on its track, which is barely curved in this case. Further indication for SUED might be the discovery of W'-like signature of mass close to Z{sub 2}. The MUED predicts a somewhat lower event rate due to 1-loop suppressed coupling of level-2 bosons to SM fermion pair, while it exists at tree level in SUED. Therefore in UED, one has to rely on indirect production of level-2 bosons, whose collider study requires complete knowledge of the model: the mass spectrum and all the couplings. On the other hand, in the large {mu} limit of SUED, the dependence on mass spectrum is diminished since level-2 KK bosons decay only into SM fermion pairs. This allows us to estimate the signal rate from their direct production, so that they can be discovered at the early phase of the LHC. The indirect production mechanism only increases production cross sections, improving our results. Once a discovery has been made, one should try to reconstruct events and do further measurements such as spin and coupling determination, with more accumulated data, which might discriminate KK resonances from other Z' models. The coupling measurement is directly related to the determination of the bulk masses. A challenging issue might be the existence of two resonances which are rather close to each other.

Kong, Kyoungchul; /SLAC; Park, Seong Chan; /Tokyo U., IPMU; Rizzo, Thomas G.; /SLAC

2011-12-15T23:59:59.000Z

234

A minimal and predictive $T_7$ lepton flavor 331 model  

E-Print Network [OSTI]

We present a model based on the $SU(3)_{C}\\otimes SU(3)_{L}\\otimes U(1)_{X}$ gauge group having an extra $T_{7}\\otimes Z_{3}\\otimes Z_{14}$ flavor group, where the light active neutrino masses arise via double seesaw mechanism and the observed charged lepton mass hierarchy is a consequence of the $Z_{14}$ symmetry breaking at very high energy. In our minimal and predictive $T_7$ lepton flavor 331 model, the spectrum of neutrinos includes very light active neutrinos and heavy and very heavy sterile neutrinos. The obtained neutrino mixing parameters and neutrino mass squared splittings are compatible with the neutrino oscillation experimental data, for both normal and inverted hierarchies. The model predicts CP conservation in neutrino oscillations.

Hernández, A E Cárcamo

2015-01-01T23:59:59.000Z

235

U(2)? flavor symmetry and lepton universality violation in W?????  

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

The seeming violation of universality in the ? lepton coupling to the W boson suggested by LEP-II data is studied using an effective field theory (EFT) approach. Within this framework we explore how this feature fits into the current constraints from electroweak precision observables using different assumptions about the flavor structure of New Physics, namely [U(2)×U(1)]? and U(2)?. We show the importance of leptonic and semileptonic tau decay measurements, giving 3–4 TeV bounds on the New Physics effective scale at 90% C.L. We conclude under very general assumptions that it is not possible to accommodate this deviation from universality in the EFT framework, and thus such a signal could only be explained by the introduction of light degrees of freedom or New Physics strongly coupled at the electroweak scale.

Filipuzzi, Alberto; Portolés, Jorge; González-Alonso, Martín

2012-06-01T23:59:59.000Z

236

Electroweak Penguin and Leptonic Decays at BaBar  

SciTech Connect (OSTI)

Recent BABAR results on electroweak penguin and leptonic decays are reviewed. In particular, the measurements of B {yields} K{sup (*)}l{sup +}l{sup -} and the preliminary results on B {yields} X{sub s}l{sup +}l{sup -} are presented. Also summarized are the preliminary limits on B{sup +} {yields} l{sup +}{nu} (l = e,{mu}) and B{sup +} {yields} K{sup +}{nu}{bar {nu}}.

Bucci, F.; /Pisa U. /INFN, Pisa

2005-08-26T23:59:59.000Z

237

The standard model and the constituents of leptons and quarks  

E-Print Network [OSTI]

A complete set of postulates of the standard model of the electroweak interaction and mass generation is formulated and confirmed deriving the Lagrangian for the standard model. A massive fermion is formed by a right-handed and a left-handed elementary massless fermion, exchanging a scalar doublet. The elementary massless fermions forming leptons belong to an approximate SU(3) octet. The charges are quantised due to this symmetry.

Walter Schmidt-Parzefall

2014-03-04T23:59:59.000Z

238

Lepton Flavour Violation in Tau Decays at BaBar  

SciTech Connect (OSTI)

Recent results from {tau} physics studies at BABAR are presented with an emphasis on Lepton Flavour Violation measurements. The results from the current generation of B-meson Factories are already beginning to constrain the parameter space of models that go beyond the Standard Model. By the end of their data-taking, the current generation of B-meson factories will have produced nearly 2 billion {tau} pair decays. The physics potential of this legacy has only just begun to be exploited.

Wilson, F.F.; /Rutherford

2011-11-07T23:59:59.000Z

239

Lepton flavor violation two-body decays of quarkoniums  

E-Print Network [OSTI]

In this paper we firstly study various model-independent bounds on lepton flavor violation (LFV) in processes of $J/\\Psi$, $\\Psi'$ and $\\Upsilon$ two-body decays, then calculate their branch ratios % By using the constraints from other ways, we obtain %the indirect bounds of ${\\rm Br} (J/\\Psi,\\Psi',\\Upsilon \\to ll')$ in models of the leptoquark, $R$ violating MSSM and topcolor assisted technicolor(TC2) models.

W. J. Huo; T. F. Feng; Y. C. Xing

2002-12-15T23:59:59.000Z

240

Statistical Understanding of Quark and Lepton Masses in Gaussian Landscapes  

E-Print Network [OSTI]

The fundamental theory of nature may allow a large landscape of vacua. Even if the theory contains a unified gauge symmetry, the 22 flavor parameters of the Standard Model, including neutrino masses, may be largely determined by the statistics of this landscape, and not by any symmetry. Then the measured values of the flavor parameters do not lead to any fundamental symmetries, but are statistical accidents; their precise values do not provide any insights into the fundamental theory, rather the overall pattern of flavor reflects the underlying landscape. We investigate whether random selection from the statistics of a simple landscape can explain the broad patterns of quark, charged lepton, and neutrino masses and mixings. We propose Gaussian landscapes as simplified models of landscapes where Yukawa couplings result from overlap integrals of zero-mode wavefunctions in higher-dimensional supersymmetric gauge theories. In terms of just five free parameters, such landscapes can account for all gross features of flavor, including: the hierarchy of quark and charged lepton masses; small quark mixing angles, with 13 mixing less than 12 and 23 mixing; very light Majorana neutrino masses, with the solar to atmospheric neutrino mass ratio consistent with data; distributions for leptonic 12 and 23 mixings that are peaked at large values, while the distribution for 13 mixing is peaked at low values; and order unity CP violating phases in both the quark and lepton sectors. While the statistical distributions for flavor parameters are broad, the distributions are robust to changes in the geometry of the extra dimensions. Constraining the distributions by loose cuts about observed values leads to narrower distributions for neutrino measurements of 13 mixing, CP violation, and neutrinoless double beta decay.

Lawrence J. Hall; Michael P. Salem; Taizan Watari

2007-08-10T23:59:59.000Z

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241

TOP AND HIGGS PHYSICS AT THE HADRON COLLIDERS  

SciTech Connect (OSTI)

This review summarizes the recent results for top quark and Higgs boson measurements from experiments at Tevatron, a proton–antiproton collider at a center-of-mass energy of ? s =1 . 96 TeV, and the Large Hadron Collider, a proton–proton collider at a center- of-mass energy of ? s = 7 TeV. These results include the discovery of a Higgs-like boson and measurement of its various properties, and measurements in the top quark sector, e.g. top quark mass, spin, charge asymmetry and production of single top quark.

Jabeen, Shabnam

2013-10-20T23:59:59.000Z

242

Alignment tolerance of accelerating structures and corrections for future linear colliders  

SciTech Connect (OSTI)

The alignment tolerance of accelerating structures is estimated by tracking simulations. Both single-bunch and multi-bunch effects are taken into account. Correction schemes for controlling the single and multi-bunch emittance growth in the case of large misalignment are also tested by simulations.

Kubo, K.; Adolphsen, C.; Bane, K.L.F.; Raubenheimer, T.O.; Thompson, K.A.

1995-06-01T23:59:59.000Z

243

Linear Collider LHC Subpanel | 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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman, 1960 The Ernest OrlandoJohnLegislativeLinac

244

SciTech Connect: A Beam Driven Plasma-Wakefield Linear Collider: From Higgs  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systems controller systemsisSchedulesenrichedoil shale"ProgramFactory

245

A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory to Multi-TeV  

Office of Scientific and Technical Information (OSTI)

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article: Crystal structureComposite JC-118794 PREPRINTWillisHormetic0123RD MIAMIA Beam

246

Detector for the Linear Collider General Detector Concepts and Detector Performance  

E-Print Network [OSTI]

Conveners: M. Martinez, D.J. Miller, M. Piccolo Working Group: A. Andreazza, M. Battaglia, G. Blair, G. A d, A. Andreazza, P. Bambade, T. Barklow, W. Bartel, M. Battaglia, R. Bellanzzini, S. Bertolucci, G

247

The scalar unparticle effect on the charged lepton electric dipole moment  

E-Print Network [OSTI]

We study the charged lepton electric dipole moment which is induced by the scalar unparticle mediation and we predict the appropriate range for the free parameters appearing in the effective lagrangian which drives the unparticle-standard model lepton interactions. We observe that the charged lepton electric dipole moment is strongly sensitive to the scaling dimension d_u of the unparticle and the new couplings in the effective interaction. Furthermore, we see that the current experimental limits of charged lepton electric dipole moments can ensure an appropriate range for these free parameters.

E. O. Iltan

2007-10-14T23:59:59.000Z

248

E-Print Network 3.0 - analyses lepton scattering Sample Search...  

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

leptons and missing... +p, e-p data Analyses presented utilize the final combined dataset 1 fb-1 Recontres de ... Source: Raval, Amita - ZEUS DESY & Department of Physics,...

249

Weak Boson Emission in Hadron Collider Processes  

E-Print Network [OSTI]

The O(alpha) virtual weak radiative corrections to many hadron collider processes are known to become large and negative at high energies, due to the appearance of Sudakov-like logarithms. At the same order in perturbation theory, weak boson emission diagrams contribute. Since the W and Z bosons are massive, the O(alpha) virtual weak radiative corrections and the contributions from weak boson emission are separately finite. Thus, unlike in QED or QCD calculations, there is no technical reason for including gauge boson emission diagrams in calculations of electroweak radiative corrections. In most calculations of the O(alpha) electroweak radiative corrections, weak boson emission diagrams are therefore not taken into account. Another reason for not including these diagrams is that they lead to final states which differ from that of the original process. However, in experiment, one usually considers partially inclusive final states. Weak boson emission diagrams thus should be included in calculations of electroweak radiative corrections. In this paper, I examine the role of weak boson emission in those processes at the Fermilab Tevatron and the CERN LHC for which the one-loop electroweak radiative corrections are known to become large at high energies (inclusive jet, isolated photon, Z+1 jet, Drell-Yan, di-boson, t-bar t, and single top production). In general, I find that the cross section for weak boson emission is substantial at high energies and that weak boson emission and the O(alpha) virtual weak radiative corrections partially cancel.

U. Baur

2006-11-17T23:59:59.000Z

250

Cryogenics for the Large Hadron Collider  

E-Print Network [OSTI]

The Large Hadron Collider (LHC), a 26.7 km circumference superconducting accelerator equipped with high-field magnets operating in superfluid helium below 1.9 K, has now fully entered construction at CERN, the European Laboratory for Particle Physics. The heart of the LHC cryogenic system is the quasi-isothermal magnet cooling scheme, in which flowing two-phase saturated superfluid helium removes the heat load from the 36'000 ton cold mass, immersed in some 400 m3 static pressurised superfluid helium. The LHC also makes use of supercritical helium for non-isothermal cooling of the beam screens which intercept most of the dynamic heat loads at higher temperature. Although not used in normal operation, liquid nitrogen will provide the source of refrigeration for precooling the machine. Refrigeration for the LHC is produced in eight large refrigerators, each with an equivalent capacity of about 18 kW at 4.5 K, completed by 1.8 K refrigeration units making use of several stages of hydrodynamic cold compressors. T...

Lebrun, P

1999-01-01T23:59:59.000Z

251

Cryogenics for the Large Hadron Collider  

E-Print Network [OSTI]

The Large Hadron Collider (LHC), a 26.7 km circumference superconducting accelerator equipped with high-field magnets operating in superfluid helium below 1.9 K, has now fully entered construction at CERN, the European Laboratory for Particle Physics. The heart of the LHC cryogenic system is the quasi-isothermal magnet cooling scheme, in which flowing two-phase saturated superfluid helium removes the heat load from the 36000 ton cold mass, immersed in some 400 m/sup 3/ static pressurised superfluid helium. The LHC also makes use of supercritical helium for nonisothermal cooling of the beam screens which intercept most of the dynamic heat loads at higher temperature. Although not used in normal operation, liquid nitrogen will provide the source of refrigeration for precooling the machine. Refrigeration for the LHC is produced in eight large refrigerators, each with an equivalent capacity of about 18 kW at 4.5 K, completed by 1.8 K refrigeration units making use of several stages of hydrodynamic cold compressor...

Lebrun, P

2000-01-01T23:59:59.000Z

252

Rf System Requirements for JLab’s MEIC Collider Ring  

SciTech Connect (OSTI)

The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. At the top energy are the electron and ion collider rings. For the ion ring, it accelerates five long ion bunches to colliding energy and rebunches ions into a train of very short bunches before colliding. A set of low frequency RF system is needed for the long ion bunch energy ramping. Another set of high frequency RF cavities is needed to rebunch ions. For the electron ring, superconducting RF (SRF) cavities are needed to compensate the synchrotron radiation energy loss. The impedance of the SRF cavities must be low enough to keep the high current electron beam stable. The preliminary design requirements of these RF cavities are presented.

Wang, Shaoheng [JLAB; Li, Rui [JLAB; Rimmer, Robert A. [JLAB; Wang, Haipeng [JLAB; Zhang, Yuhong [JLAB

2013-06-01T23:59:59.000Z

253

Global QCD Analysis and Collider Phenomenology--CTEQ  

E-Print Network [OSTI]

An overview is given of recent progress on a variety of fronts in the global QCD analysis of the parton structure of the nucleon and its implication for collider phenomenology, carried out by various subgroups of the CTEQ collaboration.

Wu-Ki Tung; H. L. Lai; J. Pumplin; P. Nadolsky; C. -P. Yuan

2007-07-02T23:59:59.000Z

254

Higgs boson production at hadron colliders: Signal and background processes  

SciTech Connect (OSTI)

We review the theoretical status of signal and background calculations for Higgs boson production at hadron colliders. Particular emphasis is given to missing NLO results, which will play a crucial role for the Tevatron and the LHC.

David Rainwater; Michael Spira; Dieter Zeppenfeld

2004-01-12T23:59:59.000Z

255

H and A Discrimination using Linear Polarization of Photons at the PLC  

E-Print Network [OSTI]

First realistic estimate of the usefulness of the Photon Linear Collider with linearly polarized photons as analyzer of the CP-parity of Higgs bosons is presented. MSSM Higgs bosons H and A with 300 GeV mass, for the model parameters corresponding to the so called "LHC wedge" region, are considered. When switching from circular to linear photon polarization a significant increase in heavy quark production background, which is no longer suppressed by helicity conservation, and decrease of the Higgs boson production cross sections by a factor of two is expected. Nevertheless, after three years of Photon Linear Collider running heavy scalar and pseudoscalar Higgs bosons in MSSM can be distinguished at a 4.5 sigma level.

A. F. Zarnecki; P. Niezurawski; M. Krawczyk

2007-10-20T23:59:59.000Z

256

Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider  

E-Print Network [OSTI]

We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon 197Au79+ beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both meth...

Bruce, R; Fischer, W; Jowett, J M

2010-01-01T23:59:59.000Z

257

Probing the Quark Sea and Gluons: the Electron-Ion Collider Projects  

SciTech Connect (OSTI)

EIC is the generic name for the nuclear science-driven Electron-Ion Collider presently considered in the US. Such an EIC would be the world’s first polarized electron-proton collider, and the world’s first e-A collider. Very little remains known about the dynamical basis of the structure of hadrons and nuclei in terms of the fundamental quarks and gluons of Quantum Chromodynamics (QCD). A large community effort to sharpen a compelling nuclear science case for an EIC occurred during a ten-week program taking place at the Institute for Nuclear Theory (INT) in Seattle from September 13 to November 19, 2010. The critical capabilities of a stage-I EIC are a range in center-of-mass energies from 20 to 70 GeV and variable, full polarization of electrons and light ions (the latter both longitudinal and transverse), ion species up to A=200 or so, multiple interaction regions, and a high luminosity of about 10{sup 34} electron-nucleons per cm{sup 2} and per second. The physics program of such a stage-I EIC encompass inclusive measurements (ep/A{yields}e'+X), which require detection of the scattered lepon and/or the full scattered hadronic debris with high precision, semi-inclusive processes (ep/A{yields}e'+h+X), which require detection in coincidence with the scattered lepton of at least one (current or target region) hadron; and exclusive processes (ep/A{yields}e'+N'/A'+{gamma}/m), which require detection of all particles in the reaction. The main science themes of an EIC are to i) map the spin and spatial structure of quarks and gluons in nucleons, ii) discover the collective effects of gluons in atomic nuclei, and (iii) understand the emergence of hadronic matter from color charge. In addition, there are opportunities at an EIC for fundamental symmetry and nucleon structure measurements using the electroweak probe. To truly make headway to image the sea quarks and gluons in nucleons and nuclei, the EIC needs high luminosity over a range of energies as more exclusive scattering probabilities are small, and any integrated detector/interaction region design needs to provide uniform coverage to detect spectator and diffractive products. This is because e-p and even more e-A colliders have a large fraction of their science related to what happens to the nucleon or ion beams. As a result, the philosophy of integration of complex detectors into an extended interaction region faces challenging constraints. Designs feature crossing angles between the protons or heavy ions during collisions with electrons, to remove potential problems for the detector induced by synchrotron radiation. Designs allocate quite some detector space before the final-focus ion quads, at the cost of luminosity, given that uniform detection coverage is a must for deep exclusive and diffractive processes. The integrated EIC detector/interaction region design at JLab focused on establishing full acceptance for such processes over a wide range of proton energies (20-100 GeV) with well achievable interaction region magnets. The detector design at BNL uses the higher ion beam energies to achieve good detection efficiency for instance for protons following a DVCS reaction, for proton beam energies starting from 100 GeV. Following a recommendation of the 2007 US Nuclear Science Long-Range Planning effort, the DOE Office of Nuclear Physics (DOE/NP) has allocated accelerator R&D funds to lay the foundation for a polarized EIC. BNL, in association with JLab and DOE/NP, has also established a generic detector R&D program to address the scientific requirements for measurements at a future EIC.

Rolf Ent

2012-04-01T23:59:59.000Z

258

arhioluhi tshto zh: Topics by E-print Network  

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

at International Linear Collider (ILC). Using e+e- -> ZH process, the mass of Higgs boson can be measured by two lepton tracks from decay of Z boson, even if the Higgs boson...

259

atf2 high availability: Topics by E-print Network  

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

a prototype scaled demonstrator system for the final focus required for a future high energy lepton linear collider. The ATF2 beam-line is instrumented with a total of 41 high...

260

Next-to-Next-to-Leading-Order Subtraction Formalism in Hadron Collisions and its Application to Higgs-Boson Production at the Large Hadron Collider  

SciTech Connect (OSTI)

We consider higher-order QCD corrections to the production of colorless high-mass systems (lepton pairs, vector bosons, Higgs bosons, etc.) in hadron collisions. We propose a new formulation of the subtraction method to numerically compute arbitrary infrared-safe observables for this class of processes. To cancel the infrared divergences, we exploit the universal behavior of the associated transverse-momentum (q{sub T}) distributions in the small-q{sub T} region. The method is illustrated in general terms up to the next-to-next-to-leading order in QCD perturbation theory. As a first explicit application, we study Higgs-boson production through gluon fusion. Our calculation is implemented in a parton level Monte Carlo program that includes the decay of the Higgs boson into two photons. We present selected numerical results at the CERN Large Hadron Collider.

Catani, Stefano; Grazzini, Massimiliano [INFN, Sezione di Firenze and Dipartimento di Fisica, Universita di Firenze, I-50019 Sesto Fiorentino, Florence (Italy)

2007-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Searches for Leptonic B Decays at BaBar  

SciTech Connect (OSTI)

Measurements of the branching fractions of purely leptonic decays of B-mesons translate into constraints in the plane of the charged Higgs mass versus tan {beta} which are relatively insensitive to the particular theoretical model. Using the full BABAR dataset of 450 million B-decays we search for these decays. No significant signal is found in the decays into electrons or muons and we set upper limits on the branching fractions of the order of a 10{sup -6} at 90% confidence level. We measure the branching fraction of B {yields} {tau}{mu} to be (1.7 {+-} 0.6) x 10{sup -4}.

Nelson, Silke; /SLAC

2012-04-25T23:59:59.000Z

262

Muon g-2 Anomaly and Dark Leptonic Gauge Boson  

SciTech Connect (OSTI)

One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.

Lee, Hye-Sung [W& M

2014-11-01T23:59:59.000Z

263

Leptonic CP violation: zero, maximal or between the two extremes  

E-Print Network [OSTI]

Discovery of the CP-violation in the lepton sector is one of the challenges of the particle physics. We search for possible principles, symmetries and phenomenological relations that can lead to particular values of the CP-violating Dirac phase, $\\delta$. In this connection we discuss two extreme cases: the zero phase, $\\delta = 0$, and the maximal CP-violation, $\\delta = \\pm \\pi/2$, and relate them to the peculiar pattern of the neutrino mixing. The maximal CP-violation can be related to the $\

Y. Farzan; A. Yu. Smirnov

2006-10-25T23:59:59.000Z

264

On Field Emission in High Energy Colliders Initiated by a Relativistic Positively Charged Bunch of Particles  

E-Print Network [OSTI]

The design of the LHC and future colliders aims their operation with high intensity beams, with bunch population, $N_p$, of the order of $10^{11}$. This is dictated by a desire to study very rare processes with maximum data sample. HEP colliders are engineering structures of many kilometers in length, whose transverse compactness is achieved by the application of the superconducting technologies and limitations of cost. However the compactness of the structural elements conceals and potential danger for the stable work of the accelerator. This is because a high intensity beam of positively charged particles (protons, positrons, ions) creates around itself an electric self-field of very high intensity, $10^5 - 10^6$ V/cm. Being located near the conducting surfaces, at the distances of 1-20 mm away from them, the field of such bunches activates the field emission of electrons from the surface. These electrons, in addition to electrons from the ionization of residual gases, secondary electrons and electrons knocked out by synchrotron radiation, contribute to the development of a dense electron cloud in the transport line. The particles of the bunch, being scattered on the dense electron cloud with $N_e\\sim N_p$, leaves the beam and may cause noticeable damage. The paper presents an analysis of the conditions, under which the field emission in the LHC collimator system may become a serious problem. The analogous analysis of a prototype of the International Linear Collider (ILC) project, USLC, reveals that a noticeable field emission will accompany positron bunches on their entire path during acceleration.

B. B. Levchenko

2006-08-12T23:59:59.000Z

265

Search for tau -> gamma mu: A test of lepton number conservation  

E-Print Network [OSTI]

A search for the lepton number violating decay of the tau lepton to the gammamu final state has been performed with the CLEO II detector at the Cornell e+e- storage ring CESR. In a data sample that corresponds to an ...

Ammar, Raymond G.; Ball, S.; Baringer, Philip S.; Coppage, Don; Copty, N.; Davis, Robin E. P.; Hancock, N.; Kelly, M.; Kwak, Nowhan; Lam, H.

1993-01-01T23:59:59.000Z

266

Electron generation of leptons and hadrons with reciprocal -quantized lifetimes and masses  

E-Print Network [OSTI]

1 Electron generation of leptons and hadrons with reciprocal -quantized lifetimes and masses generation occurs via an initial "-leap" from an electron pair to a "platform state" M, and then subsequent in the generation of hadron masses. In fact, the role of the electron in generating lepton masses has never been

267

Electric Dipole moments of charged leptons and lepton flavor violating interactions in the general two Higgs Doublet model  

E-Print Network [OSTI]

We calculate the electric dipole moment of electron using the experimental result of muon electric dipole moment and upper limit of the BR(\\mu --> e\\gamma) in the framework of the general two Higgs doublet model. Our prediction is 10^{-32} e-cm, which lies in the experimental current limits. Further, we obtain constraints for the Yukawa couplings \\bar{\\xi}^{D}_{N,\\tau e} and \\bar{\\xi}^{D}_{N,\\tau\\mu}. Finally we present an expression which connects the BR(\\tau\\to \\mu\\gamma) and the electric dipole moment of \\tau-lepton and study the relation between these physical quantities.

E. O. Iltan

2001-05-17T23:59:59.000Z

268

Quark and lepton masses and mixing in the landscape  

E-Print Network [OSTI]

Even if quark and lepton masses are not uniquely predicted by the fundamental theory, as may be the case in the string theory landscape, nevertheless their pattern may reveal features of the underlying theory. We use statistical techniques to show that the observed masses appear to be representative of a scale invariant distribution, rho(m) ~ 1/m. If we extend this distribution to include all the Yukawa couplings, we show that the resulting CKM matrix elements typically show a hierarchical pattern similar to observations. The Jarlskog invariant measuring the amount of CP violation is also well reproduced in magnitude. We also apply this framework to neutrinos using the seesaw mechanism. The neutrino results are ambiguous, with the observed pattern being statistically allowed even though the framework does not provide a natural explanation for the observed two large mixing angles. Our framework highly favors a normal hierarchy of neutrino masses. We also are able to make statistical predictions in the neutrino sector when we specialize to situations consistent with the known mass differences and two large mixing angles. Within our framework, we show that with 95% confidence the presently unmeasured MNS mixing angle sin theta_{13} is larger than 0.04 and typically of order 0.1. The leptonic Jarlskog invariant is found to be typically of order 10^{-2} and the magnitude of the effective Majorana mass m_{ee} is typically of order 0.001 eV.

John F. Donoghue; Koushik Dutta; Andreas Ross

2006-01-27T23:59:59.000Z

269

Multi Leptons in ep Collisions at HERA Analyses of multi-muon & and multi-electron production  

E-Print Network [OSTI]

Multi Leptons in ep Collisions at HERA Analyses of multi-muon & and multi-electron production Boris Lei�ner, RWTH Aachen on behalf of the and collaborations B. Lei�ner, Multi Leptons in ep Collisions - 1 for additional leptons e e e p · Conclusions B. Lei�ner, Multi Leptons in ep Collisions - 2 #12;Outline · How

270

Inverse neutrinoless double beta decay revisited: Neutrinos, Higgs triplets, and a muon collider  

SciTech Connect (OSTI)

We revisit the process of inverse neutrinoless double beta decay (e{sup -}e{sup -{yields}}W{sup -}W{sup -}) at future linear colliders. The cases of Majorana neutrino and Higgs triplet exchange are considered. We also discuss the processes e{sup -{mu}-{yields}}W{sup -}W{sup -} and {mu}{sup -{mu}-{yields}}W{sup -}W{sup -}, which are motivated by the possibility of muon colliders. For heavy neutrino exchange, we show that masses up to 10{sup 6} (10{sup 5}) GeV could be probed for ee and e{mu} machines, respectively. The stringent limits for mixing of heavy neutrinos with muons render {mu}{sup -{mu}-{yields}}W{sup -}W{sup -} less promising, even though this process is not constrained by limits from neutrinoless double beta decay. If Higgs triplets are responsible for inverse neutrinoless double beta decay, observable signals are only possible if a very narrow resonance is met. We also consider unitarity aspects of the process in case both Higgs triplets and neutrinos are exchanged. An exact seesaw relation connecting low energy data with heavy neutrino and triplet parameters is found.

Rodejohann, Werner [Max-Planck-Institut fuer Kernphysik, Postfach 103980, D-69029 Heidelberg (Germany)

2010-06-01T23:59:59.000Z

271

Polarization Effects In The Charged Lepton Pair Production By A Neutrino (Antineutrino) In A Magnetic Field  

SciTech Connect (OSTI)

The probability of the process of the charged lepton pair production by a neutrino (an antineutrino) with allowance for the longitudinal and transverse polarizations of the charged leptons in a magnetic field is presented. The dependence of the probability of the process on the spin variables of the charged leptons and on the azimuthal and polar angles of the initial and final neutrinos (antineutrinos) are investigated. It is shown that the probability of the process is sensitive to the spin variables of the charged leptons and to the direction of the neutrino (antineutrino) momentum. It is determined that the neutrino (antineutrino) energy and momentum loss through the production of a charged lepton pair happens asymmetrically.

Huseynov, Vali A. [Department of General and Theoretical Physics, Nakhchivan State University, AZ 7000, Nakhchivan (Azerbaijan); Laboratory of Physical Research, Nakhchivan Division of Azerbaijan National Academy of Sciences, AZ 7000, Nakhchivan (Azerbaijan); Ahmad, Ali S. [Department of General and Theoretical Physics, Nakhchivan State University, AZ 7000, Nakhchivan (Azerbaijan)

2007-06-13T23:59:59.000Z

272

Transverse beams stability studies at the Large Hadron Collider  

E-Print Network [OSTI]

A charged particle beam travelling at the speed of light produces large electromagnetic wake fields which, through interactions with its surroundings, act back on the particles in the beam. This coupled system may become unstable, resulting in a deterioration of the beam quality. Such effects play a major role in most existing storage rings, as they limit the maximum performance achievable. In a collider, the presence of a second beam significantly changes the dynamics, as the electromagnetic interactions of the two beams on each other are usually very strong and may, also, limit the collider performances. This thesis treats the coherent stability of the two beams in a circular collider, including the effects of the electromagnetic wake fields and of the beam-beam interactions, with particular emphasis on CERN's Large Hadron Collider. As opposed to other colliders, this machine features a large number of bunches per beam each experiencing multiple long-range and head-on beam-beam interactions. Existing models...

Buffat, Xavier; Pieloni, Tatiana

2015-01-30T23:59:59.000Z

273

Massive Stars in Colliding Wind Systems: the GLAST Perspective  

SciTech Connect (OSTI)

Colliding winds of massive stars in binary systems are considered as candidate sites of high-energy non-thermal photon emission. They are already among the suggested counterparts for a few individual unidentified EGRET sources, but may constitute a detectable source population for the GLAST observatory. The present work investigates such population study of massive colliding wind systems at high-energy gamma-rays. Based on the recent detailed model (Reimer et al. 2006) for non-thermal photon production in prime candidate systems, we unveil the expected characteristics of this source class in the observables accessible at LAT energies. Combining the broadband emission model with the presently cataloged distribution of such systems and their individual parameters allows us to conclude on the expected maximum number of LAT-detections among massive stars in colliding wind binary systems.

Reimer, Anita; Reimer, Olaf; /Stanford U., HEPL /KIPAC, Menlo Park

2011-11-29T23:59:59.000Z

274

Symmetric Achromatic Low-Beta Collider Interaction Region Design Concept  

SciTech Connect (OSTI)

We present a new symmetry-based concept for an achromatic low-beta collider interaction region design. A specially-designed symmetric Chromaticity Compensation Block (CCB) induces an angle spread in the passing beam such that it cancels the chromatic kick of the final focusing quadrupoles. Two such CCB?s placed symmetrically around an interaction point allow simultaneous compensation of the 1st-order chromaticities and chromatic beam smear at the IP without inducing significant 2nd-order aberrations. We first develop an analytic description of this approach and explicitly formulate 2nd-order aberration compensation conditions at the interaction point. The concept is next applied to develop an interaction region design for the ion collider ring of an electron-ion collider. We numerically evaluate performance of the design in terms of momentum acceptance and dynamic aperture. The advantages of the new concept are illustrated by comparing it to the conventional distributed-sextupole chromaticity compensation scheme.

Morozov, Vasiliy S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Derbenev, Yaroslav S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Lin, Fanglei [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Johnson, Rolland P. [Muons, Inc., Batavia, IL (United States)

2013-01-01T23:59:59.000Z

275

Emergent cosmological constant from colliding electromagnetic waves  

E-Print Network [OSTI]

In this study we advocate the view that the cosmological constant is of electromagnetic (em) origin, which can be generated from the collision of em shock waves coupled with gravitational shock waves. The wave profiles that participate in the collision have different amplitudes. It is shown that, circular polarization with equal amplitude waves does not generate cosmological constant. We also prove that the generation of the cosmological constant is related to the linear polarization. The addition of cross polarization generates no cosmological constant. Depending on the value of the wave amplitudes, the generated cosmological constant can be positive or negative. We show additionally that, the collision of nonlinear em waves in a particular class of Born-Infeld theory also yields a cosmological constant.

M. Halilsoy; S. Habib Mazharimousavi; O. Gurtug

2014-10-15T23:59:59.000Z

276

A concept of the photon collider beam dump  

E-Print Network [OSTI]

Photon beams at photon colliders are very narrow, powerful (10--15 MW) and cannot be spread by fast magnets (because photons are neutral). No material can withstand such energy density. For the ILC-based photon collider, we suggest using a 150 m long, pressurized (P ~ 4 atm) argon gas target in front of a water absorber which solves the overheating and mechanical stress problems. The neutron background at the interaction point is estimated and additionally suppressed using a 20 m long hydrogen gas target in front of the argon.

L. I. Shekhtman; V. I. Telnov

2014-09-19T23:59:59.000Z

277

Optical data transmission at the superconducting super collider  

SciTech Connect (OSTI)

Digital and analog data transmissions via fiber optics for the Superconducting Super Collider have been investigated. The state of the art of optical transmitters, low loss fiber waveguides, receivers and associated electronics components are reviewed and summarized. Emphasis is placed on the effects of the radiation environment on the performance of an optical data transmission system components. Also, the performance of candidate components of the wide band digital and analog transmission systems intended for deployment of the Superconducting Super Collider Detector is discussed. 27 refs., 15 figs.

Leskovar, B.

1989-02-01T23:59:59.000Z

278

Collider Detector at Fermilab (CDF): Data from B Hadrons Research  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group is organized into six working groups, each with a specific focus. The Bottom group studies the production and decay of B hadrons. Their public web page makes data and numerous figures available from both CDF Runs I and II.

279

History of Proton Linear Accelerators  

E-Print Network [OSTI]

much. References 1. Linear Accelerators, edited by P. M .at the 1986 Linear Accelerator Conference, SLAC, Stanford,HISTORY OF PROTON LINEAR ACCELERATORS Luis W. Alvarez TWO-

Alvarez, Luis W.

1987-01-01T23:59:59.000Z

280

Generalized lepton number and dark left-right gauge model  

SciTech Connect (OSTI)

In a left-right gauge model of particle interactions, the left-handed fermion doublet ({nu},e){sub L} is connected to its right-handed counterpart (n,e){sub R} through a scalar bidoublet so that e{sub L} pairs with e{sub R}, and {nu}{sub L} with n{sub R} to form mass terms. Suppose the latter link is severed without affecting the former, then n{sub R} is not the mass partner of {nu}{sub L}, and as we show in this paper, becomes a candidate for dark matter which is relevant for the recent PAMELA and ATIC observations. We accomplish this in a specific nonsupersymmetric model, where a generalized lepton number can be defined, so that n{sub R} and W{sub R}{sup {+-}} are odd under R{identical_to}(-1){sup 3B+L+2j}. Fermionic leptoquarks are also predicted.

Khalil, Shaaban [Center for Theoretical Physics, British University in Egypt, El Sherouk City, Postal No. 11837, P.O. Box 43 (Egypt); Department of Mathematics, Ain Shams University, Faculty of Science, Cairo 11566 (Egypt); Lee, Hye-Sung; Ma, Ernest [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States)

2009-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Higgs Production in Neutralino Decays in the MSSM - The LHC and a Future e+e- Collider  

E-Print Network [OSTI]

The search for the production of weakly-interacting SUSY particles at the LHC is crucial for testing supersymmetry in relation to dark matter. Decays of neutralinos into Higgs bosons occur over some significant part of the SUSY parameter space and represent the most important source of $h$ boson production in SUSY decay chains in the MSSM. We study h production in neutralino decays using scans of the phenomenological MSSM. Whilst in constrained MSSM scenarios the decay chi^0_2 -> h chi^0_1 is the dominant channel, this does not hold in more general MSSM scenarios. On the other hand, the chi^0_2,3 -> h chi^0_1 decays remain important and are highly complementary to multi-lepton final states in the LHC searches. The perspectives for the LHC analyses at 8 and 14 TeV as well as the reach of an e+e- collider at 0.5, 1, 1.5 and 3 TeV are discussed.

Alexandre Arbey; Marco Battaglia; Farvah Mahmoudi

2015-02-10T23:59:59.000Z

282

Search for Higgs and new phenomena at colliders  

SciTech Connect (OSTI)

The present status of searches for the Higgs boson(s) and new phenomena is reviewed. The focus is on analyses and results from the current runs of the HERA and Tevatron experiments. The LEP experiments have released their final combined MSSM Higgs results for this conference. Also included are results from sensitivity studies of the LHC experiments and lepton flavor violating searches from the B factories, KEKB and PEP-II.

Lammel, Stephan; /Fermilab

2006-01-01T23:59:59.000Z

283

Unit I-2 Linear Maps 1 Linear maps  

E-Print Network [OSTI]

Unit I-2 Linear Maps 1 Unit I-2 Linear maps Unit I-2 Linear Maps 2 Linear map · V & U are vector spaces over the same scalars · a function f: VU is a linear map if it preserves the vector space transformation [particularly when f: RnRm] ­ linear operator when f: V V [same v.s.] ­ linear mapping ­ linear

Birkett, Stephen

284

Searches for Lepton Flavor Violation in the Decays tau+- ---> e+- gamma and tau+- ---> mu+- gamma  

SciTech Connect (OSTI)

Searches for lepton-flavor-violating decays of a {tau} lepton to a lighter mass lepton and a photon have been performed with the entire dataset of (963 {+-} 7) x 10{sup 6} {tau} decays collected by the BABAR detector near the {Upsilon}(4S), {Upsilon}(3S) and {Upsilon}(2S) resonances. The searches yield no evidence of signals and they set upper limits on the branching fractions of {Beta}({tau}{sup {+-}} {yields} e{sup {+-}}{gamma}) < 3.3 x 10{sup -8} and {Beta}({tau}{sup {+-}} {yields} {mu}{sup {+-}}{gamma}) < 4.4 x 10{sup -8} at 90% confidence level.

Aubert, Bernard; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, David Nathan; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS; /more authors.; ,

2010-06-11T23:59:59.000Z

285

Falsifying High-Scale Baryogenesis with Neutrinoless Double Beta Decay and Lepton Flavor Violation  

E-Print Network [OSTI]

Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the universe. In this letter, we discuss the constraints obtained from an observation of neutrinoless double beta decay in this context. If a new physics mechanism of neutrinoless double beta decay is observed, typical scenarios of high-scale baryogenesis will be excluded unless the baryon asymmetry is stabilized via some new mechanism. We also sketch how this conclusion can be extended beyond the first lepton generation by incorporating lepton flavor violating processes.

Frank F. Deppisch; Julia Harz; Martin Hirsch; Wei-Chih Huang; Heinrich Päs

2015-03-16T23:59:59.000Z

286

Falsifying High-Scale Baryogenesis with Neutrinoless Double Beta Decay and Lepton Flavor Violation  

E-Print Network [OSTI]

Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the universe. In this letter, we discuss the constraints obtained from an observation of neutrinoless double beta decay in this context. If a new physics mechanism of neutrinoless double beta decay is observed, typical scenarios of high-scale baryogenesis will be excluded unless the baryon asymmetry is stabilized via some new mechanism. We also sketch how this conclusion can be extended beyond the first lepton generation by incorporating lepton flavor violating processes.

Deppisch, Frank F; Hirsch, Martin; Huang, Wei-Chih; Päs, Heinrich

2015-01-01T23:59:59.000Z

287

Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider  

E-Print Network [OSTI]

We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon Au beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both methods to make predictions of the time evolution of the future Pb beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

R. Bruce; M. Blaskiewicz; W. Fischer; J. M. Jowett

2010-09-08T23:59:59.000Z

288

E-Print Network 3.0 - asymmetric colliding nuclei Sample Search...  

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

colliding nuclei Search Powered by Explorit Topic List Advanced Search Sample search results for: asymmetric colliding nuclei Page: << < 1 2 3 4 5 > >> 1 managed for the U.S....

289

A Detector Scenario for the MuonCollider Cooling Experiment  

E-Print Network [OSTI]

: Meson Lab at Fermilab: Power Supplies (two floors) Cooling Apparatus Muon Beamline shielding shieldingA Detector Scenario for the Muon­Collider Cooling Experiment C. Lu, K.T. McDonald and E.J. Prebys the emittance of the muon beam to 3% accuracy before and after the muon cooling apparatus. 1 #12; Possible site

McDonald, Kirk

290

First events and prospects at the Fermilab collider  

SciTech Connect (OSTI)

A brief description of the Collider Detector at Fermilab (CDF) is given including the detector components and the data acquisition system. The first test run, the first events, and the performance of the detector are discussed. Finally the prospects for future running are reviewed.

Binkley, M.

1986-03-01T23:59:59.000Z

291

AN INTENSE LOW ENERGY MUON SOURCE FOR THE MUON COLLIDER  

E-Print Network [OSTI]

AN INTENSE LOW ENERGY MUON SOURCE FOR THE MUON COLLIDER D. Taqqu Paul Scherrer Institut, Villigen, CH Abstract A scheme for obtaining an intense source of low energy muons is described. It is based of the decay muons an intense intermediate energy muon beam is obtained. For the specific case of negative

McDonald, Kirk

292

MERCURY HANDLING FOR THE TARGET SYSTEM FOR A MUON COLLIDER  

E-Print Network [OSTI]

MERCURY HANDLING FOR THE TARGET SYSTEM FOR A MUON COLLIDER (IPAC12, WEPPD038) The target station a 15-20 T superconducting magnet. The target itself is a free mercury jet, moving at 20 m/s at an small angle to the magnetic axis, so as later to be collected in a mercury pool/beam dump. The replaceable

McDonald, Kirk

293

MERCURY HANDLING FOR THE TARGET SYSTEM FOR A MUON COLLIDER  

E-Print Network [OSTI]

MERCURY HANDLING FOR THE TARGET SYSTEM FOR A MUON COLLIDER Van Graves , ORNL, Oak Ridge, TN 37830 Factory is a free-stream mercury jet within a 20-T magnetic field being impacted by an 8-GeV proton beam. A pool of mercury serves as a receiving reservoir for the mercury and a dump for the unexpended proton

McDonald, Kirk

294

Collider shot setup for Run 2 observations and suggestions  

SciTech Connect (OSTI)

This note is intended to provoke discussion on Collider Run II shot setup. We hope this is a start of activities that will converge on a functional description of what is needed for shot setups in Collider Run II. We will draw on observations of the present shot setup to raise questions and make suggestions for the next Collider run. It is assumed that the reader has some familiarity with the Collider operational issues. Shot setup is defined to be the time between the end of a store and the time the Main Control Room declares colliding beams. This is the time between Tevatron clock events SCE and SCB. This definition does not consider the time experiments use to turn on their detectors. This analysis was suggested by David Finley. The operational scenarios for Run II will require higher levels of reliability and speed for shot setup. See Appendix I and II. For example, we estimate that a loss of 3 pb{sup {minus}1}/week (with 8 hour stores) will occur if shot setups take 90 minutes instead of 30 minutes. In other words: If you do 12 shots for one week and accept an added delay of one minute in each shot, you will loose more than 60 nb{sup {minus}1} for that week alone (based on a normal shot setup of 30 minutes). These demands should lead us to be much more pedantic about all the factors that affect shot setups. Shot setup will be viewed as a distinct process that is composed of several inter- dependent `components`: procedures, hardware, controls, and sociology. These components don`t directly align with the different Accelerator Division departments, but are topical groupings of the needed accelerator functions. Defining these components, and categorizing our suggestions within them, are part of the goal of this document. Of course, some suggestions span several of these components.

Annala, J.; Joshel, B.

1996-01-31T23:59:59.000Z

295

Higgs-boson production at the Photon Collider at TESLA  

E-Print Network [OSTI]

In this thesis feasibility of the precise measurement of the Higgs-boson production cross section gamma+gamma->higgs->b+bbar at the Photon Collider at TESLA is studied in detail. The study is based on the realistic luminosity spectra simulation. The heavy quark background is estimated using the dedicated code based on NLO QCD calculations. Other background processes, which were neglected in the earlier analyses, are also studied. Also the contribution from the overlaying events, gamma+gamma->hadrons, is taken into account. The non-zero beam crossing angle and the finite size of colliding bunches are included in the event generation. The analysis is based on the full detector simulation with realistic b-tagging, and the criteria of event selection are optimized separately for each considered Higgs-boson mass. For the Standard-Model Higgs boson with mass of 120 to 160 GeV the partial width \\Gamma(h->gamma+gamma)BR(h->b+bbar) can be measured with a statistical accuracy of 2.1-7.7% after one year of the Photon Collider running. The systematic uncertainties of the measurement are estimated to be of the order of 2%. For MSSM Higgs bosons A and H, for M_A=200-350 GeV and tan(beta)=7, the statistical precision of the cross-section measurement is estimated to be 8--34%, for four considered MSSM parameters sets. As heavy neutral Higgs bosons in this scenario may not be discovered at LHC or at the first stage of the e+e- collider, an opportunity of being a discovery machine is also studied for the Photon Collider.

Piotr Niezurawski

2005-03-31T23:59:59.000Z

296

Production cross section and topological decay branching fractions of the ? lepton  

E-Print Network [OSTI]

We report new measurements of the production cross section for the reaction e(+)e(?)??(+)?(?) at s?=29 GeV, as well as the topological decay branching fractions of the ? lepton. The data were taken with the High Resolution ...

Baringer, Philip S.

1989-08-01T23:59:59.000Z

297

Lepton Flavor Violation in tau and B decays at BaBar  

SciTech Connect (OSTI)

This article summarizes the search for lepton flavor violating {tau} and B decays, using data collected by the BABAR detector at the PEP-II asymmetric-energy B factory.

Manoni, Elisa; /Perugia U. /INFN, Perugia

2008-07-11T23:59:59.000Z

298

The Inclusive Semileptonic Decay Lepton Spectrum from $B \\to X e \\overline?$  

E-Print Network [OSTI]

In this talk, we review the QCD calculation of the lepton spectrum from inclusive semileptonic $B$ decay. We compare this prediction to that of the ACCMM model. This latter work was done in collaboration with Csaba Csaki.

Lisa Randall

1994-07-15T23:59:59.000Z

299

Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions  

E-Print Network [OSTI]

A search for neutral Higgs bosons in the minimal supersymmetric extension of the standard model (MSSM) decaying to tau-lepton pairs in pp collisions is performed, using events recorded by the CMS experiment at the LHC. The ...

CMS Collaboration

300

The Mu2e Experiment at Fermilab: a Search for Charged Lepton Flavor Violation  

E-Print Network [OSTI]

The Mu2e Experiment at Fermilab: a Search for Charged Lepton Flavor of the Mu2e Collaboration. A new experiment, Mu2e, is being developed at Fermilab

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Impact of Lepton Number Violation at the LHC on Models of Leptogenesis  

E-Print Network [OSTI]

The discovery of lepton number violation (LNV) at the LHC would have profound consequences for the viability of high-scale leptogenesis models. As an example, we discuss the case of observing a signal with two same-sign leptons, two jets and no missing energy. This would imply a large washout factor for the lepton number density in the early Universe, which leads to a significant constraint on any high-scale model for the generation of the observed baryon asymmetry. In a standard leptogenesis scenario, the corresponding washout factor would strongly decrease a pre-existing lepton asymmetry and thus would render leptogenesis models that generate a (B-L) asymmetry far above the LHC scale ineffective. Therefore, LHC searches focused on LNV processes without missing energy are powerful probes for high-scale leptogenesis models and correspondingly shed light on the nature of baryogenesis and neutrino masses.

Frank F. Deppisch; Julia Harz

2014-08-22T23:59:59.000Z

302

Time evolution of colliding laser produced magnesium plasmas investigated using a pinhole camera  

E-Print Network [OSTI]

suitable conditions for x-ray amplification in a laser produced plasma.24 When two plasmas collide, variTime evolution of colliding laser produced magnesium plasmas investigated using a pinhole camera S for publication 14 February 2001 Time resolved studies of colliding laser produced magnesium plasmas are performed

Harilal, S. S.

303

Physics and Analysis at a Hadron Collider - An Introduction (1/3)  

ScienceCinema (OSTI)

This is the first lecture of three which together discuss the physics of hadron colliders with an emphasis on experimental techniques used for data analysis. This first lecture provides a brief introduction to hadron collider physics and collider detector experiments as well as offers some analysis guidelines. The lectures are aimed at graduate students.

None

2011-10-06T23:59:59.000Z

304

Test of Lepton Flavour Universality in K+ --> l+nu Decays  

E-Print Network [OSTI]

A precision test of lepton flavour universality has been performed by measuring the ratio RK of kaon leptonic decay rates K+ --> e+nu and K+ --> mu+nu in a sample of 59813 reconstructed K+ --> e+nu candidates with (8.71 +- 0.24)% background contamination. The result RK = (2.487 +- 0.013) * 10^{-5} is in agreement with the Standard Model expectation.

C. Lazzeroni et al.

2011-03-01T23:59:59.000Z

305

Prospects for Searching for Excited Leptons during RunII of the Fermilab Tevatron  

E-Print Network [OSTI]

This letter presents a study of prospects of searching for excited leptons during RunII of the Fermilab Tevatron. We concentrate on single and pair production of excited electrons in the photonic decay channel in one CDF/DO detector equivalent for 2 fb^{-1}. By the end of RunIIa, the limits should be easily extended beyond those set by LEP and HERA for excited leptons with mass above about 190 GeV.

E. Boos; A. Vologdin; D. Toback; J. Gaspard

2001-11-05T23:59:59.000Z

306

Calculation of conventional and prompt lepton fluxes at very high energy  

E-Print Network [OSTI]

An efficient method for calculating inclusive conventional and prompt atmospheric leptons fluxes is presented. The coupled cascade equations are solved numerically by formulating them as matrix equation. The presented approach is very flexible and allows the use of different hadronic interaction models, realistic parametrizations of the primary cosmic-ray flux and the Earth's atmosphere, and a detailed treatment of particle interactions and decays. The power of the developed method is illustrated by calculating lepton flux predictions for a number of different scenarios.

Fedynitch, Anatoli; Gaisser, Thomas K; Riehn, Felix; Stanev, Todor

2015-01-01T23:59:59.000Z

307

Almost Maximal Lepton Mixing with Large T Violation in Neutrino Oscillations and Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

We point out two simple but instructive possibilities to construct the charged lepton and neutrino mass matrices, from which the nearly bi-maximal neutrino mixing with large T violation can naturally emerge. The two lepton mixing scenarios are compatible very well with current experimental data on solar and atmospheric neutrino oscillations, and one of them may lead to an observable T-violating asymmetry between \

Zhi-zhong Xing

2001-07-02T23:59:59.000Z

308

Measurement of the Single Top Quark Cross Section in the Lepton Plus Jets Final State in Proton-Antiproton Collisions at a Center of Mass Energy of 1.96 TeV Using the CDF II Detector  

SciTech Connect (OSTI)

We present a measurement of the single top quark cross section in the lepton plus jets final state using an integrated luminosity corresponding to 7.5~\\text{fb}^{-1} of p\\bar p collision data collected by the Collider Detector at Fermilab. The single top candidate events are identified by the signature of a charged lepton, large missing transverse energy, and two or three jets with at least one of them identified as originating from a bottom quark. A new Monte Carlo generator \\textsc{powheg} is used to model the single top quark production processes, which include {s}-channel, {t}-channel, and {Wt}-channel. A neural network multivariate method is exploited to discriminate the single top quark signal from the comparatively large backgrounds. We measure a single top production cross section of $3.04^{+0.57}_{-0.53}$ (\\mathrm{stat.~+~syst.}) pb assuming $m_{\\rm top}=172.5$~GeV/$c^2$. In addition, we extract the CKM matrix element value $|V_{tb}|=0.96\\pm 0.09~(\\mathrm{stat.~+~syst.})\\pm 0.05~(\\mathrm{theory})$ and set a lower limit of |V_{tb}|>0.78 at the 95\\% credibility level.

Wu, Zhenbin

2012-01-01T23:59:59.000Z

309

Proceedings of the 1992 workshops on high-energy physics with colliding beams. Volume 1, Search for new phenomena at colliding-beam facilities  

SciTech Connect (OSTI)

This report contains brief papers and viewgraphs on high energy topics like: supersymmetry; new gauge bosons; and new high energy colliders.

Rogers, J. [ed.

1992-12-31T23:59:59.000Z

310

Lepton Flavor Violation in Predictive SUSY-GUT Models  

SciTech Connect (OSTI)

There have been many theoretical models constructed which aim to explain the neutrino masses and mixing patterns. While many of the models will be eliminated once more accurate determinations of the mixing parameters, especially sin{sup 2} 2{theta}{sub 13}, are obtained, charged lepton flavor violation (LFV) experiments are able to differentiate even further among the models. In this paper, they investigate various rare LFV processes, such as {ell}{sub i} {yields} {ell}{sub j} + {gamma} and {mu} - e conversion, in five predictive SUSY SO(10) models and their allowed soft SUSY breaking parameter space in the constrained minimal SUSY standard model (CMSSM). Utilizing the WMAP dark matter constraints, they obtain lower bounds on the branching ratios of these rare processes and find that at least three of the five models they consider give rise to predictions for {mu} {yields} e + {gamma} that will be tested by the MEG collaboration at PSI. in addition, the next generation {mu} - e conversion experiment has sensitivity to the predictions of all five models, making it an even more robust way to test these models. While generic studies have emphasized the dependence of the branching ratios of these rare processes on the reactor neutrino angle, {theta}{sub 13}, and the mass of the heaviest right-handed neutrino, M{sub 3}, they find very massive M{sub 3} is more significant than large {theta}{sub 13} in leading to branching ratios near to the present upper limits.

Albright, Carl H.; /Northern Illinois U. /Fermilab; Chen, Mu-Chun; /UC, Irvine

2008-02-01T23:59:59.000Z

311

Higgs boson decay into four leptons at NLOPS electroweak accuracy  

E-Print Network [OSTI]

In view of precision studies of the Higgs sector at the Run II of the LHC, the improvement of the accuracy of the theoretical prediction is becoming a pressing issue. In this framework, we detail a calculation of the full Next-to-Leading Order (NLO) electroweak corrections to Higgs boson decay into four charged leptons, by considering the gold-plated channel H -> Z(*) Z(*) -> 2l 2l', l,l' = e, mu. We match the NLO corrections with a QED Parton Shower (PS), in order to simulate exclusive multiple photon emission and provide novel results at NLOPS electroweak accuracy. We compare our NLO predictions to those of the program Prophecy4f and present NLOPS phenomenological results relevant for Higgs physics studies, with particular attention to precision measurements of the Higgs boson mass, spin-parity assignment and tests of the Standard Model. Our calculation is implemented in a new code, Hto4l, which can be easily interfaced to any generator describing Higgs boson production. As an example, we provide illustrati...

Boselli, Stefano; Montagna, Guido; Nicrosini, Oreste; Piccinini, Fulvio

2015-01-01T23:59:59.000Z

312

QED peripheral mechanism of pair production at colliders  

SciTech Connect (OSTI)

Cross sections of the processes of production of neutral pions and pairs of charged fermions and bosons in peripheral interaction of leptons and photons are calculated in the main logarithmic approximation. We investigate the phase volumes and differential cross sections. The differential cross sections of production of a few neutral pions and a few pairs are written down explicitly. Considering the academic problem of summation over a number of pairs for massless particles we reproduce the known results obtained in the 1970s. The possibility of constructing the generator for Monte Carlo modeling of these processes based on these results is discussed.

Ahmadov, A. I.; Galynskii, M. V.; Bystritskiy, Yu. M.; Kuraev, E. A.; Shatnev, M. G. [Joint Institute for Nuclear Research, Dubna, Russia, and Institute of Physics, Azerbaijan National Academy of Sciences, Baku (Azerbaijan); Institute of Physics, Minsk (Belarus); Joint Institute for Nuclear Research, Dubna (Russian Federation); Kharkov Institute of Physics and Technology, Kharkov, 61108 (Ukraine)

2008-10-01T23:59:59.000Z

313

R&D Toward a Neutrino Factory and Muon Collider  

SciTech Connect (OSTI)

There is considerable interest in the use of muon beams to create either an intense source of decay neutrinos aimed at a detector located 3000-7500 km away (a Neutrino Factory), or a Muon Collider that produces high-luminosity collisions at the energy frontier. R&D aimed at producing these facilities has been under way for more than 10 years. This paper will review experimental results from MuCool, MERIT, and MICE and indicate the extent to which they will provide proof-of-principle demonstrations of the key technologies required for a Neutrino Factory or Muon Collider. Progress in constructing components for the MICE experiment will also be described.

Zisman, Michael S

2009-04-29T23:59:59.000Z

314

Learning to See at the Large Hadron Collider  

SciTech Connect (OSTI)

The staged commissioning of the Large Hadron Collider presents an opportunity to map gross features of particle production over a significant energy range. I suggest a visual tool - event displays in (pseudo)rapidity-transverse-momentum space - as a scenic route that may help sharpen intuition, identify interesting classes of events for further investigation, and test expectations about the underlying event that accompanies large-transverse-momentum phenomena.

Quigg, Chris

2010-01-01T23:59:59.000Z

315

LFV decays and anomalous magnetic (electric) moments in a lepton mass matrices ansatz induced by SUSY GUT  

E-Print Network [OSTI]

By using the anomalous magnetic and electric dipole moments of the $\\tau$ lepton in an effective lagrangian approach to the new physics, we investigate the lepton flavor violation (LFV) decays, $l\\to l'\\gamma$, and $\\mu,\\tau$ anomalous magnetic and electric dipole moments in a lepton mass matrices ansatz which induced by SUSY GUT. We put very stringent constraints LFV decays and $\\tau$ anomalous magnetic and electric dipole moments.

W. J. Huo

2003-01-27T23:59:59.000Z

316

Finite element analyses of a linear-accelerator electron gun  

SciTech Connect (OSTI)

Thermo-structural analyses of the Beijing Electron-Positron Collider (BEPCII) linear-accelerator, electron gun, were performed for the gun operating with the cathode at 1000?°C. The gun was modeled in computer aided three-dimensional interactive application for finite element analyses through ANSYS workbench. This was followed by simulations using the SLAC electron beam trajectory program EGUN for beam optics analyses. The simulations were compared with experimental results of the assembly to verify its beam parameters under the same boundary conditions. Simulation and test results were found to be in good agreement and hence confirmed the design parameters under the defined operating temperature. The gun is operating continuously since commissioning without any thermal induced failures for the BEPCII linear accelerator.

Iqbal, M., E-mail: muniqbal.chep@pu.edu.pk, E-mail: muniqbal@ihep.ac.cn [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan); Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Wasy, A. [Department of Mechanical Engineering, Changwon National University, Changwon 641773 (Korea, Republic of)] [Department of Mechanical Engineering, Changwon National University, Changwon 641773 (Korea, Republic of); Islam, G. U. [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan)] [Centre for High Energy Physics, University of the Punjab, Lahore 45590 (Pakistan); Zhou, Z. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)] [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

2014-02-15T23:59:59.000Z

317

Perturbations to $?-?$ Symmetry, Leptogenesis and Lepton Flavour Violation with Type II Seesaw  

E-Print Network [OSTI]

We study the possibility of generating non-zero reactor mixing angle $\\theta_{13}$ by perturbing the $\\mu-\\tau$ symmetric neutrino mass matrix. The leading order $\\mu-\\tau$ symmetric neutrino mass matrix originates from type I seesaw mechanism whereas the perturbations to $\\mu-\\tau$ symmetry originate from type II seesaw term. We consider four different realizations of $\\mu-\\tau$ symmetry: Bimaximal Mixing(BM), Tri-bimaximal Mixing (TBM), Hexagonal Mixing (HM) and Golden Ratio Mixing (GRM) all giving rise to $\\theta_{13} = 0, \\theta_{23} = \\frac{\\pi}{4}$ but different non-zero values of solar mixing angle $\\theta_{12}$. We assume a minimal $\\mu-\\tau$ symmetry breaking type II seesaw mass matrix as a perturbation and calculate the neutrino oscillation parameters as a function of type II seesaw strength. We then consider the origin of non-trivial leptonic CP phase in the charged lepton sector and calculate the lepton asymmetry arising from the lightest right handed neutrino decay by incorporating the presence of both type I and type II seesaw. We constrain the type II seesaw strength as well as leptonic CP phase (and hence the charged lepton sector) by comparing our results with experimental neutrino oscillation parameters as well as Planck bound on baryon to photon ratio. Finally, we extend our analysis on lepton flavour violating decays like $\\mu \\to e \\gamma$ and $\\mu \\to eee$ due to exchange of TeV scale Higgs triplet scalar within the low scale type II seesaw framework. The branching ratios for these lepton flavour processes are examined with the small type II perturbation term $\\omega$ and the estimated values are very close to the experimental bound coming from current search experiments.

Manikanta Borah; Debasish Borah; Mrinal Kumar Das; Sudhanwa Patra

2014-10-17T23:59:59.000Z

318

Structure Functions in Deep Inelastic Lepton Scattering: Data from DOE laboratory experiments as compiled in data reviews by the Durham High Energy Physics Database Group  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Gehrmann, Roberts, and Whalley in their 1999 paper, A Compilation of Structure Functions in Deep Inelastic Scattering, published in volume 25 of Journal of Physics G (Nuclear and Particle Physics) note that these data will continue to be relevant to the next generation of hadron colliders. They present data on the unpolarized structure functions F2 and xF3, R D ._L=_T /, the virtual photon asymmetries A1 and A2 and the polarized structure functions g1 and g2, from deep inelastic lepton scattering off protons, deuterium and nuclei. Data are presented in both tabular and graphical format and include predictions based on the MRST98 and CTEQ4 parton distribution functionsö as well. The data gathered from the relevant collaborations at DOE's Fermilab, SLAC, and JLAB are available, and so are data from related collaborations based at CERN and DESY. The Durham High Energy Physics (HEP) Database Group makes these data, extracted from papers and data reviews, available in one place in an easy-to-access format. These data are also include in the Durham HEP Reaction Data Database which can be searched at http://hepdata.cedar.ac.uk/reaction

Gehrmann, T; Roberts, R.G.; Whalley, M.R.; Durham HEP Database Group

319

Measurements of the Higgs boson mass and width in the four-lepton final state and electron reconstruction in the CMS experiment at the LHC  

E-Print Network [OSTI]

This thesis document reports measurements of the mass and width of the new boson re- cently discovered at the Large Hadron Collider (LHC), candidating to be the Standard Model Higgs boson. The analysis uses proton-proton collision data recorded by the Compact Muon Solenoid (CMS) detector at the LHC, corresponding to integrated luminosities of $5.1~fb^{?1}$ at $7~$TeV center of mass energy and $19.7~fb^{?1}$ at $8~$TeV center of mass energy. Set of events selecting Higgs boson via the $H\\to ZZ$ decay channel, where both $Z$ bosons decay to electron or muon lepton pairs, is used for the Higgs boson properties measurements. A precise measurement of its mass has been performed and gives $125.6\\pm0.4\\mbox{(stat)}\\pm0.2\\mbox{(syst)}~$GeV. Constraints on the Higgs boson width were established using its off-shell production and decay to a pair of $Z$ bosons, where one $Z$ boson decays to an electron or muon pair, and the other to an electron, muon, or neutrino pair. The obtained result is an upper limit on the Hi...

Dalchenko, Mykhailo; Charlot, Claude

320

Robust Linear Optimization With Recourse  

E-Print Network [OSTI]

We propose an approach to two-stage linear optimization with recourse that does ... Linear optimization with recourse was first introduced by Dantzig in [17] as a ...

2010-05-19T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Linear Quantum Feedback Networks  

E-Print Network [OSTI]

The mathematical theory of quantum feedback networks has recently been developed for general open quantum dynamical systems interacting with bosonic input fields. In this article we show, for the special case of linear dynamical systems Markovian systems with instantaneous feedback connections, that the transfer functions can be deduced and agree with the algebraic rules obtained in the nonlinear case. Using these rules, we derive the the transfer functions for linear quantum systems in series, in cascade, and in feedback arrangements mediated by beam splitter devices.

J. Gough; R. Gohm; M. Yanagisawa

2008-07-15T23:59:59.000Z

322

Linear Programming Environmental  

E-Print Network [OSTI]

Linear Program to control air pollution was developed in 1968 by Teller, which minimized cost Fall 2006 #12;Topics · Introduction · Background · Air · Land · Water #12;Introduction · "The United States spends more than 2% of its gross domestic product on pollution control, and this is more than any

Nagurney, Anna

323

On the lepton-nucleon neutral and charged current deep inelastic scattering cross sections  

E-Print Network [OSTI]

Based on the requirement in the simulation of lepton-nucleus deep inelastic scattering (DIS), we construct a fortran program LDCS 1.0 calculating the differential and total cross sections for the unpolarized charged lepton-unpolarized nucleon and neutrino-unpolarized nucleon neutral current (charged current) DIS at leading order. Any set of the experimentally fitted parton distribution functions could be employed directly. The mass of incident and scattered leptons is taken into account and the boundary conditions calculating the single differential and total cross section are studied. The calculated results well agree with the corresponding experimental data which indicating the LDCS 1.0 program is good. It is also turned out that the effect of tauon mass is not negligible in the GeV energy level.

Xing-Long Li; Yu-Liang Yan; Xiao-Mei Li; Dai-Mei Zhou; Xu Cai; Ben-Hao Sa

2014-12-17T23:59:59.000Z

324

Anomalous magnetic and electric moments of $?$ and lepton flavor mixing matrix in effective lagrangian approach  

E-Print Network [OSTI]

In an effective lagrangian approach [EM97] to new physics, the authors in ref. [HL99] pushed tau anomalous magnetic and electric dipole moments (AMDM and EDM) down to $10^{-11}$ and $10^{-25} e cm$ by using a Fritzsch-Xing lepton mass matrix ansatz. In this note, we find that, in this approach, there exists the connection between $\\tau$ AMDM and EDM and the lepton flavor mixing matrix. By using the current neutrino oscillation experimental results, we investigate the parameter space of lepton mixing angles to $\\tau$ AMDM and EDM. We can obtain the same or smaller bounds of $\\delta a_\\tau$ and $d_\\tau$ acquired in ref. [HL99] and constrain $\\theta_l$ (the mixing angle obtained by long-baseline neutrino oscillation experiments) from $\\tau$ AMDM and EDM.

J. Q. Zhang; X. C. Song; W. J. Huo; T. F. Feng

2002-06-17T23:59:59.000Z

325

On the possibility of observable signatures of leptonic onium atoms from astrophysical sources  

E-Print Network [OSTI]

The formation of Ps in our Galaxy is well measured, and has led to important and unanswered questions on the origin of the positrons. In principle it should be possible to form analogous systems from mu and tau leptons, viz. true muonium and true tauonium. However the probability of formation for these systems is greatly reduced due to the intrinsically short lifetimes of the mu and tau leptons. Likewise, the decay of the atoms is hastened by the high probability of the constituent particles decaying. Nevertheless, if significant numbers of mu and tau pairs are produced in high energy astrophysical environments there may be significant production of true muonium and true tauonium, despite the small probabilities. This paper addresses this possibility. We have calculated the pair production spectra of mu and tau leptons from photon-photon annihilation and electron-positron annihilation in astrophysical environments. We have computed the cross-sections for radiative recombination and direct annihilation of the ...

Ellis, S C

2015-01-01T23:59:59.000Z

326

HIGH-ENERGY PARTICLE COLLIDERS: PAST 20 YEARS, NEXT 20 YEARS, AND BEYOND  

SciTech Connect (OSTI)

Particle colliders for high-energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the colliders has progressed immensely, while the beam energy, luminosity, facility size, and cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This paper briefly reviews the colliding beam method and the history of colliders, discusses the development of the method over the last two decades in detail, and examines near-term collider projects that are currently under development. The paper concludes with an attempt to look beyond the current horizon and to find what paradigm changes are necessary

Shiltsev, V.

2013-09-25T23:59:59.000Z

327

Radiative Return Capabilities of a High-Energy, High-Luminosity $e^+e^-$ Collider  

E-Print Network [OSTI]

An electron-positron collider operating at a center-of-mass energy $E_{CM}$ can collect events at all lower energies through initial-state radiation (ISR or radiative return). We explore the capabilities for radiative return studies by a proposed high-luminosity collider at $E_{CM}$ = 250 or 90 GeV, to fill in gaps left by lower-energy colliders such as PEP, PETRA, TRISTAN, and LEP. These capabilities are compared with those of the lower-energy $e^+e^-$ colliders as well as hadron colliders such as the Tevatron and the CERN Large Hadron Collider (LHC). Some examples of accessible questions in dark photon searches and heavy flavor spectroscopy are given.

Karliner, Marek; Rosner, Jonathan L; Wang, Lian-Tao

2015-01-01T23:59:59.000Z

328

PHENIX Conceptual Design Report. An experiment to be performed at the Brookhaven National Laboratory Relativistic Heavy Ion Collider  

SciTech Connect (OSTI)

The PHENIX Conceptual Design Report (CDR) describes the detector design of the PHENIX experiment for Day-1 operation at the Relativistic Heavy Ion Collider (RHIC). The CDR presents the physics capabilities, technical details, cost estimate, construction schedule, funding profile, management structure, and possible upgrade paths of the PHENIX experiment. The primary goals of the PHENIX experiment are to detect the quark-gluon plasma (QGP) and to measure its properties. Many of the potential signatures for the QGP are measured as a function of a well-defined common variable to see if any or all of these signatures show a simultaneous anomaly due to the formation of the QGP. In addition, basic quantum chromodynamics phenomena, collision dynamics, and thermodynamic features of the initial states of the collision are studied. To achieve these goals, the PHENIX experiment measures lepton pairs (dielectrons and dimuons) to study various properties of vector mesons, such as the mass, the width, and the degree of yield suppression due to the formation of the QGP. The effect of thermal radiation on the continuum is studied in different regions of rapidity and mass. The e{mu} coincidence is measured to study charm production, and aids in understanding the shape of the continuum dilepton spectrum. Photons are measured to study direct emission of single photons and to study {pi}{sup 0} and {eta} production. Charged hadrons are identified to study the spectrum shape, production of antinuclei, the {phi} meson (via K{sup +}K{sup {minus}} decay), jets, and two-boson correlations. The measurements are made down to small cross sections to allow the study of high p{sub T} spectra, and J/{psi} and {Upsilon} production. The PHENIX collaboration consists of over 300 scientists, engineers, and graduate students from 43 institutions in 10 countries. This large international collaboration is supported by US resources and significant foreign resources.

Not Available

1993-01-29T23:59:59.000Z

329

Experimental Study of W Z Intermediate Bosons Associated Production with the CDF Experiment at the Tevatron Collider  

SciTech Connect (OSTI)

Studying WZ associated production at the Fermilab Tevatron Collider is of great importance for two main reasons. On the one hand, this process would be sensitive to anomalies in the triple gauge couplings such that any deviation from the value predicted by the Standard Model would be indicative of new physics. In addition, by choosing to focus on the final state where the Z boson decays to b{bar b} pairs, the event topology would be the same as expected for associated production of a W and a Standard Model light Higgs boson (m{sub H} {approx}< 135 GeV) which decays into b{bar b} pairs most of times. The process WH {yields} W b{bar b} has an expected {sigma} {center_dot} B about five times lower than WZ {yields} Wb{bar b} for m{sub H} {approx_equal} 120 GeV. Therefore, observing this process would be a benchmark for an even more difficult search aiming at discovering the light Higgs in the WH {yields} Wb{bar b} process. After so many years of Tevatron operation only a weak WZ signal was recently observed in the full leptonic decay channel, which suffers from much less competition from background. Searching for the Z in the b{bar b} decay channel in this process is clearly a very challenging endeavour. In the work described in this thesis, WZ production is searched for in a final state where the W decays leptonically to an electron-neutrino pair or a muon-neutrino pair, with associated production of a jet pair consistent with Z decays. A set of candidate events is obtained by applying appropriate cuts to the parameters of events collected by wide acceptance leptonic triggers. To improve the signal fraction of the selected events, an algorithm was used to tag b-flavored jets by means of their content of long lived b-hadrons and corrections were developed to the jet algorithm to improve the b-jet energy resolution for a better reconstruction of the Z mass. In order to sense the presence of a signal one needs to estimate the amount of background. The relative content of heavy flavor jets in the dominant W+multijet background is assumed as predicted by theory. This technique was originally developed in CDF to measure the t{bar t} production cross section in the final state with W + 3 or more jets. This thesis was conceived as the first attempt within CDF to apply a customized version of it to look for evidence of diboson production in the final state with aW and two jets. Extracting the signal in this channel is very hard since with such a small number of jets the background is two orders of magnitude greater than the signal. Moreover, since the signal to background ratio is very small, the expected sensitivity depends critically on the theoretical uncertainties on the amount of background. While work is in progress to understand this background more reliably, this analysis provides an estimate of the achievable upper limit on the WZ production cross section.

Pozzobon, Nicola; /Pisa U.

2007-09-01T23:59:59.000Z

330

Measurements of Four-Lepton Production at the Z Resonance in pp Collisions at ?s = 7 and 8 TeV with ATLAS  

E-Print Network [OSTI]

Measurements of four-lepton (4?, ? = e,?) production cross sections at the Z resonance in pp collisions at the LHC with the ATLAS detector are presented. For dilepton and four-lepton invariant mass regions m[subscript ?+??] ...

Taylor, Frank E.

331

The liquid helium storage system for the Large Hadron Collider.  

E-Print Network [OSTI]

The cryogenic system of the Large Hadron Collider (LHC) under operation at CERN has a total helium inventory of 140 t. Up to 50 t can be stored in gas storage tanks. The remaining inventory will be stored in a liquid helium storage system consisting of six 15-t liquid helium tanks in 4 locations. The two liquid helium tanks of specific low heat inleak design and the required infrastructure of the first location were recently commissioned. Four additional tanks shall be operational end 2010. The paper describes the features and characteristics of the liquid helium storage system and presents the measurement of the thermal performance of the two first tanks.

Benda, V; Fathallah, M; Goiffon, T; Parente, C; Perez-Duenas, E; Perret, Ph; Pirotte, O; Serio, L; Vullierme, B

2011-01-01T23:59:59.000Z

332

Test of Little Higgs Mechanism at Future Colliders  

E-Print Network [OSTI]

In the little higgs scenario, several coupling constants are related to each other to guarantee the stability of the higgs boson mass at one-loop level. This relation is called the little higgs mechanism. We discuss how accurately the relation can be tested at future $e^+e^-$ colliders, with especially focusing on the top sector of the scenario using a method of effective lagrangian. In order to test the mechanism, it is important to measure the Yukawa coupling of the top partner. Higgs associated and threshold productions of the top partner are found to be the best processes for this purpose.

Shigeki Matsumoto

2012-02-25T23:59:59.000Z

333

Synchrotron-Radiation Photon Distribution for Highest Energy Circular Colliders  

E-Print Network [OSTI]

At high energies, beam-induced synchrotron radiation is an important source of heating, beam-related vacuum pressure increase, and primary photoelectrons, which can give rise to an electron cloud. The photon distribution along the beam pipe wall is a key input to codes such as ECLOUD and PyECLOUD, which model the electron cloud build-up. For future high-energy colliders, like TLEP or SHE-LHC, photon stops and antechambers are considered in order to facilitate cooling and vacuum pressure control. We use the Synrad3D code developed at Cornell to simulate the photon distribution for the LHC.

Maury Cuna, GHI; Dugan, G; Zimmermann, F

2013-01-01T23:59:59.000Z

334

Synchrotron-Radiation Photon Distributions for Highest Energy Circular Colliders  

E-Print Network [OSTI]

At high energies, beam-induced synchrotron radiation is an important source of heating, beam-related vacuum pressure increase, and primary photoelectrons, which can give rise to an electron cloud. The photon distribution along the beam pipe wall is a key input to codes such as ECLOUD and PyECLOUD, which model the electron cloud build-up. For future high-energy colliders, like TLEP or SHE-LHC, photon stops and antechambers are considered in order to facilitate cooling and vacuum pressure control. We use the Synrad3D code developed at Cornell to simulate the photon distribution for the LHC.

Maury Cuna, G H I; Dugan, G; Zimmermann, F

2013-01-01T23:59:59.000Z

335

Thermal conduction of SSC (Superconducting Super Collider) wire  

SciTech Connect (OSTI)

A method suitable for measuring the thermal conductivity of good thermal conductors at low temperatures was implemented. It successfully served its purpose: to detect the effect of doping with manganese the interfilament part of the copper matrix of the superconducting wire used in the magnets of the Superconducting Super Collider. It uses two heaters and one thermometer per sample reducing the accuracy requirement on the thermometers, automatically compensating for zero offsets and reducing the number of critical thermal contacts. Commercially available strain gauges are used as heaters. 3 refs., 2 figs.

Kuchnir, M.; Tague, J.L.

1989-08-01T23:59:59.000Z

336

Complementarity between collider, direct detection, and indirect detection experiments  

E-Print Network [OSTI]

We examine the capabilities of planned direct detection, indirect detection, and collider experiments in exploring the 19-parameter p(henomenological)MSSM, focusing on the complementarity between the different search techniques. In particular, we consider dark matter searches at the 7, 8 (and eventually 14) TeV LHC, \\Fermi, CTA, IceCube/DeepCore, and LZ. We see that the search sensitivities depend strongly on the WIMP mass and annihilation mechanism, with the result that different search techniques explore orthogonal territory. We also show that advances in each technique are necessary to fully explore the space of Supersymmetric WIMPs.

Matthew Cahill-Rowley

2014-11-12T23:59:59.000Z

337

Radio emission from Colliding-Wind Binaries: Observations and Models  

E-Print Network [OSTI]

We have developed radiative transfer models of the radio emission from colliding-wind binaries (CWB) based on a hydrodynamical treatment of the wind-collision region (WCR). The archetype of CWB systems is the 7.9-yr period binary WR140, which exhibits dramatic variations at radio wavelengths. High-resolution radio observations of WR140 permit a determination of several system parameters, particularly orbit inclination and distance, that are essential for any models of this system. A model fit to data at orbital phase 0.9 is shown, and some short comings of our model described.

S. M. Dougherty; J. M. Pittard; E. P. O'Connor

2005-10-18T23:59:59.000Z

338

Control Surveys for Underground Construction of the Superconducting Super Collider  

SciTech Connect (OSTI)

Particular care had to be taken in the design and implementation of the geodetic control systems for the Superconducting Super Collider (SSC) due to stringent accuracy requirements, the demanding tunneling schedule, long duration and large size of the construction effort of the project. The surveying requirements and the design and implementation of the surface and underground control scheme for the precise location of facilities which include approximately 120 km of bored tunnel are discussed. The methodology used for the densification of the surface control networks, the technique used for the transfer of horizontal and vertical control into the underground facilities, and the control traverse scheme employed in the tunnels is described.

Greening, W.J.Trevor; Robinson, Gregory L.; /Measurment Science Inc.; Robbins, Jeffrey S.; Ruland, Robert E.; /SLAC

2005-08-16T23:59:59.000Z

339

SINGLE CRYSTAL NIOBIUM TUBES FOR PARTICLE COLLIDERS ACCELERATOR CAVITIES  

SciTech Connect (OSTI)

The objective of this research project is to produce single crystal niobium (Nb) tubes for use as particle accelerator cavities for the Fermi laboratory’s International Linear Collider project. Single crystal Nb tubes may have superior performance compared to a polycrystalline tubes because the absence of grain boundaries may permit the use of higher accelerating voltages. In addition, Nb tubes that are subjected to the high temperature, high vacuum crystallization process are very pure and well annealed. Any impurity with a significantly higher vapor pressure than Nb should be decreased by the relatively long exposure at high temperature to the high vacuum environment. After application of the single crystal process, the surfaces of the Nb tubes are bright and shiny, and the tube resembles an electro polished Nb tube. For these reasons, there is interest in single crystal Nb tubes and in a process that will produce single crystal tubes. To convert a polycrystalline niobium tube into a single crystal, the tube is heated to within a few hundred ?C of the melting temperature of niobium, which is 2477 ?C. RF heating is used to rapidly heat the tube in a narrow zone and after reaching the operating temperature, the hot zone is slowly passed along the length of the tube. For crystallization tests with Nb tubes, the traverse rate was in the range of 1-10 cm per hour. All the crystallization tests in this study were performed in a water-cooled, stainless steel chamber under a vacuum of 5 x10-6 torr or better. In earliest tests of the single crystal growth process, the Nb tubes had an OD of 1.9 cm and a wall thickness of 0.15 mm. With these relatively small Nb tubes, the single crystal process was always successful in producing single crystal tubes. In these early tests, the operating temperature was normally maintained at 2200 ?C, and the traverse rate was 5 cm per hour. In the next test series, the Nb tube size was increased to 3.8 cm OD and the wall thickness was increased 0.18 mm and eventually to 0.21 mm. Again, with these larger tubes, single crystal tubes were usually produced by the crystallization process. The power supply was generally operated at full output during these tests, and the traverse rate was 5 cm per hour. In a few tests, the traverse rate was increased to 10 cm per hour, and at the faster traverse rate, single crystal growth was not achieved. In these tests with a faster traverse rate, it was thought that the tube was not heated to a high enough temperature to achieve single crystal growth. In the next series of tests, the tube OD was unchanged at 3.8 cm and the wall thickness was increased to 0.30 mm. The increased wall thickness made it difficult to reach an operating temperature above 2,000 ?C, and although the single crystal process caused a large increase in the crystal grains, no single crystal tubes were produced. It was assumed that the operating temperature in these tests was not high enough to achieve single crystal growth. In FY 2012, a larger power supply was purchased and installed. With the new power supply, temperatures above the melting point of Nb were easily obtained regardless of the tube thickness. A series of crystallization tests was initiated to determine if indeed the operating temperature of the previous tests was too low to achieve single crystal growth. For these tests, the Nb tube OD remained at 3.8 cm and the wall thickness was 0.30 mm. The first test had an operating temperature of 2,000 ?C. and the operating temperature was increased by 50 ?C increments for each successive test. The final test was very near the Nb melting temperature, and indeed, the Nb tube eventually melted in the center of the tube. These tests showed that higher temperatures did yield larger grain sizes if the traverse rate was held constant at 5 cm per hour, but no single crystal tubes were produced even at the highest operating temperature. In addition, slowing the traverse rate to as low as 1 cm per hour did not yield a single crystal tube regardless of operating temperature. At this time, it

MURPHY, JAMES E [University of Nevada, Reno] [University of Nevada, Reno

2013-02-28T23:59:59.000Z

340

Measurement of the top quark mass in lepton+jets events with secondary vertex tagging  

SciTech Connect (OSTI)

A measurement of the top quark mass with the matrix element method in the lepton + jets final state in D0 Run II is presented. Events with single isolated energetic charged lepton (electron or muon), exactly four calorimeter jets, and significant missing transverse energy are selected. Probabilities used to discriminate between signal and background are assumed to be proportional to differential cross-sections, calculated using event kinematics and folding in object resolutions and parton distribution functions. The event likelihoods constructed using these probabilities are varied with the top quark mass, m{sub t}, and the jet energy scale, JES, to give the smallest possible combined statistical + JES uncertainty.

Harrington, Robert Duane; /Northeastern U.

2007-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Texture Zero Mass Matrices and Flavor Mixing of Quarks and Leptons  

E-Print Network [OSTI]

We discuss mass matrices with four texture zeros for the quarks and leptons. The three mixing angles for the quarks and leptons are functions of the fermion masses. The results agree with the experimental data. The ratio of the masses of the first two neutrinos is given by the solar mixing angle. The neutrino masses are calculated: $m_1$ $\\approx$ 0.003 eV , $m_2$ $\\approx$ 0.012 eV , $m_3$ $\\approx$ 0.048 eV.

Fritzsch, Harald

2015-01-01T23:59:59.000Z

342

Search for Neutral Heavy Leptons in the NuTeV Experiment at Fermilab  

E-Print Network [OSTI]

Preliminary results from a search for neutral heavy leptons in the NuTeV experiment at Fermilab. The upgraded NuTeV neutrino detector for the 1996-1997 run included an instrumented decay region for the NHL search which, combined with the NuTeV calorimeter, allows detection in several decay modes (mu-mu-nu, mu-e-nu, mu-pi, e-pi, and e-e-nu). We see no evidence for neutral heavy leptons in our current search in the mass range from 0.3 GeV to 2.0 GeV decaying into final states containing a muon.

NuTeV Collaboration; R. B. Drucker

1998-11-23T23:59:59.000Z

343

Spin Asymmetries Arising In Neutrino-Lepton Processes In A Magnetic Field And Their Macroscopic Appearance  

SciTech Connect (OSTI)

We present expressions that determine the differential cross sections and energy and momentum losses for the neutrino-lepton processes {nu}le- {yields} {nu}le-, {nu}-tildele- {yields} {nu}-tildele-, {nu}l{nu}-tildel {yields} e-e+, {nu}l{nu}-tildee {yields} l-e+, {nu}le- {yields} {nu}el- in a magnetic field with allowance for the longitudinal and transverse polarizations of the charged leptons and antileptons and the results on the spin asymmetries arising in these processes.

Huseynov, Vali A. [Department of General and Theoretical Physics, Nakhchivan State University, AZ 7000, Nakhchivan (Azerbaijan); Laboratory of Physical Research, Nakhchivan Division of Azerbaijan National Academy of Sciences, AZ 7000, Nakhchivan (Azerbaijan); Gasimova, Rasmiyya E.; Akbarova, Nurida Y.; Hajiyeva, Billura T. [Department of General and Theoretical Physics, Nakhchivan State University, AZ 7000, Nakhchivan (Azerbaijan)

2007-06-13T23:59:59.000Z

344

Search for the Higgs boson in its decay into tau leptons at CMS  

E-Print Network [OSTI]

A search for the Standard Model Higgs boson in the H --> rr channel is presented. The search is performed on proton collision data collected by the Compact Muon Solenoid at the Large Hadron Collider. The data corresponds ...

Chan, Matthew Hans

2013-01-01T23:59:59.000Z

345

Duality in linearized gravity  

SciTech Connect (OSTI)

We show that duality transformations of linearized gravity in four dimensions, i.e., rotations of the linearized Riemann tensor and its dual into each other, can be extended to the dynamical fields of the theory so as to be symmetries of the action and not just symmetries of the equations of motion. Our approach relies on the introduction of two superpotentials, one for the spatial components of the spin-2 field and the other for their canonically conjugate momenta. These superpotentials are two-index, symmetric tensors. They can be taken to be the basic dynamical fields and appear locally in the action. They are simply rotated into each other under duality. In terms of the superpotentials, the canonical generator of duality rotations is found to have a Chern-Simons-like structure, as in the Maxwell case.

Henneaux, Marc; Teitelboim, Claudio [Physique Theorique et Mathematique and International Solvay Institutes, Universite Libre de Bruxelles, Campus Plaine C. P. 231, B-1050 Brussels (Belgium) and Centro de Estudios Cientificos (CECS), Valdivia (Chile); Centro de Estudios Cientificos (CECS), Valdivia (Chile)

2005-01-15T23:59:59.000Z

346

Combustion powered linear actuator  

DOE Patents [OSTI]

The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

Fischer, Gary J. (Albuquerque, NM)

2007-09-04T23:59:59.000Z

347

Linear induction accelerator  

DOE Patents [OSTI]

A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

Buttram, M.T.; Ginn, J.W.

1988-06-21T23:59:59.000Z

348

Numerical heat conduction in hydrodynamical models of colliding hypersonic flows  

E-Print Network [OSTI]

Hydrodynamical models of colliding hypersonic flows are presented which explore the dependence of the resulting dynamics and the characteristics of the derived X-ray emission on numerical conduction and viscosity. For the purpose of our investigation we present models of colliding flow with plane-parallel and cylindrical divergence. Numerical conduction causes erroneous heating of gas across the contact discontinuity which has implications for the rate at which the gas cools. We find that the dynamics of the shocked gas and the resulting X-ray emission are strongly dependent on the contrast in the density and temperature either side of the contact discontinuity, these effects being strongest where the postshock gas of one flow behaves quasi-adiabatically while the postshock gas of the other flow is strongly radiative. Introducing additional numerical viscosity into the simulations has the effect of damping the growth of instabilities, which in some cases act to increase the volume of shocked gas and can re-he...

Parkin, E R

2010-01-01T23:59:59.000Z

349

Discovery Mass Reach for Excited Quarks at Hadron Colliders  

E-Print Network [OSTI]

If quarks are composite particles then excited states are expected. We estimate the discovery mass reach as a function of integrated luminosity for excited quarks decaying to dijets at the Tevatron, LHC, and a Very Large Hadron Collider (VLHC). At the Tevatron the mass reach is 0.94 TeV for Run II (2 fb^-1) and 1.1 TeV for TeV33 (30 fb^-1). At the LHC the mass reach is 6.3 TeV for 100 fb^-1. At a VLHC with a center of mass energy, sqrt(s), of 50 TeV (200 TeV) the mass reach is 25 TeV (78 TeV) for an integrated luminosity of 10^4 fb^-1. However, an excited quark with a mass of 25 TeV would be discovered at a hadron collider with sqrt(s)=100 TeV and an integrated luminosity of 13 fb^-1, illustrating a physics example where a factor of 2 in machine energy is worth a factor of 1000 in luminosity.

Robert M. Harris

1996-09-11T23:59:59.000Z

350

A wave equation including leptons and quarks for the standard model of quantum physics in  

E-Print Network [OSTI]

A wave equation including leptons and quarks for the standard model of quantum physics in Clifford-m@orange.fr August 27, 2014 Abstract A wave equation with mass term is studied for all particles and an- tiparticles of color and antiquarks u and d. This wave equation is form invariant under the Cl 3 group generalizing

Boyer, Edmond

351

Higher twist contributions to lepton-pair production and other QCD processes  

SciTech Connect (OSTI)

A general discussion of the calculations and phenomenological consequences of power-law suppressed QCD processes is given with emphasis on tests in massive lepton pair production. Absolutely normalized predictions are given for the leading twist (transverse current) and higher twist (longitudinal current) contributions to the meson structure function in the region of large x.

Brodsky, S.J.; Berger, E.L.; Lepage, G.P.

1982-12-01T23:59:59.000Z

352

Search for WW and WZ production in lepton plus jets final state at CDF  

E-Print Network [OSTI]

We present a search for WW and WZ production in final states that contain a charged lepton (electron or muon) and at least two jets, produced in ?s=1.96??TeV pp? collisions at the Fermilab Tevatron, using data corresponding ...

Xie, Si

353

Novel inclusive search for the Higgs boson in the four-lepton final state at CDF  

E-Print Network [OSTI]

An inclusive search for the standard model Higgs boson using the four-lepton final state in proton-antiproton collisions produced by the Tevatron at ?s=1.96??TeV is conducted. The data are recorded by the CDF II detector ...

Gomez-Ceballos, Guillelmo

354

Evidence for the 125 GeV Higgs boson decaying to a pair of ? leptons  

E-Print Network [OSTI]

A search for a standard model Higgs boson decaying into a pair of ? leptons is performed using events recorded by the CMS experiment at the LHC in 2011 and 2012. The dataset corresponds to an integrated luminosity of 4.9 ...

Apyan, Aram

355

NEUTRON IZATI ON, LEPTON ESCAPE,AND STELLAR HYDRODYNAMICS* W. David Arnett  

E-Print Network [OSTI]

NEUTRON IZATI ON, LEPTON ESCAPE,AND STELLAR HYDRODYNAMICS* W. David Arnett Enrico Fermi Institute University of Chicago 1. The Process of Neutronization.-Aftersili- con burning stellar matter has roughly equal numbers of neutrons and protons. Because neutron-star matter has a large excess of neutrons

Boyer, Edmond

356

Forschung an Lepton Collidern Abbildung 49: Perspektivische Ansicht des TESLA-Detektors.  

E-Print Network [OSTI]

Forschung an Lepton Collidern Abbildung 49: Perspektivische Ansicht des TESLA-Detektors. 86 #12An- strengung vieler Gruppen und Institute der ,,Tech- nical Design Report" für TESLA veröffentlicht wer- den von TESLA, besonders in Bereichen, die im TDR nicht ausreichend behandelt werden konnten, und die

357

The anomalous lepton magnetic moment, LFV decays and the fourth generation  

E-Print Network [OSTI]

We investigate the lepton flavor violation (LFV) decays, $\\tau\\to l\\gamma$ ($l=\\mu, e$) and $\\mu\\to e\\gamma$, and the newly observed muon $g-2$ anomaly in the framwork of a squential fourth generation model with a heavy fourth neutrino, $\

W. J. Huo; T. F. Feng

2003-01-20T23:59:59.000Z

358

Search for Associated Production of a Single Top Quark and a Higgs Boson in Leptonic Channels  

E-Print Network [OSTI]

A search for the production of a Higgs boson in association with a single top quark is presented, focusing on leptonic signatures provided by the $\\mathrm{H}\\rightarrow\\mathrm{W}\\mathrm{W}$ and $\\mathrm{H}\\rightarrow\\tau\\tau$ decay modes.

CMS Collaboration

2015-01-01T23:59:59.000Z

359

K->e nu decays and lepton flavor violation searches with Kaons  

E-Print Network [OSTI]

Recent Kaon decay studies seeking lepton-flavor violating (LFV) new-physics effects are briefly discussed. The main focus is set on precise measurements of rare or not-so-rare decays aiming at finding evidence of deviations from the SM prediction rather than on the results from direct searches of LFV transitions forbidden or ultra-rare in the SM.

T. Spadaro

2009-06-01T23:59:59.000Z

360

Measurement of top anti-top cross section in proton - anti-proton collider at s**(1/2) = 1.96-TeV  

SciTech Connect (OSTI)

Discovery of the top quark in 1995 at the Fermilab Tevatron collider concluded a long search following the 1977 discovery of bottom (b) quark [1] and represents another triumph of the Standard Model (SM) of elementary particles. Top quark is one of the fundamental fermions in the Standard Model of electroweak interactions and is the weak-isospin partner of the bottom quark. A precise measurement of top pair production cross-section would be a test of Quantum Chromodynamics (QCD) prediction. Presently, Tevatron is the world's highest energy collider where protons (p) and anti-protons ({anti p}) collide at a centre of mass energy (ps) of 1.96 TeV. At Tevatron top (t) and anti-top ({anti t}) quarks are predominantly pair produced through strong interactions--quark annihilation ({approx_equal} 85%) and gluon fusion ({approx_equal} 15%). Due to the large mass of top quark, t or {anti t} decays ({approx} 10{sup -25} sec) before hadronization and in SM framework, it decays to a W boson and a b quark with {approx} 100% branching ratio (BR). The subsequent decay of W boson determines the major signatures of t{anti t} decay. If both W bosons (coming from t and {anti t} decays) decay into leptons (viz., ev{sub e}, {mu}{nu}{sub {mu}} or {tau}{nu}{sub {tau}}) the corresponding t{bar t} decay is called dileptonic decay. Of all dileptonic decay modes of t{bar t}, the t{bar t} {yields} WWb{anti b} {yields} ev{sub e}{mu}{nu}{sub {mu}}b{anti b} (e{mu} channel) decay mode has the smallest background contamination from Z{sup 0} production or Drell-Yan process; simultaneously, it has the highest BR ({approx} 3.16%) [2] amongst all dileptonic decay modes of t{bar t}. During Run I (1992-1996) of Tevatron, three e{mu} candidate events were detected by D0 experiment, out of 80 candidate events (inclusive of all decay modes of t{bar t}). Due to the rarity of the t{bar t} events, the measured cross-section has large uncertainty in its value (viz., 5.69 {+-} 1.21(stat) {+-} 1.04(sys) pb {at} {radical}s = 1.8 TeV measured by D0 [3]). This analysis presents a cross section measurement in e{mu} channel utilizing {approx} 228 pb{sup -1} of data collected by D0 experiment during Tevatron Run II (between June 2002 and April 2004).

Mal, Prolay Kumar; /Tata Inst.; ,

2005-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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361

2780 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 39, NO. 11, NOVEMBER 2011 Jetlike Emission From Colliding  

E-Print Network [OSTI]

attractive applications in the field of X-ray lasers, pulsed-laser deposition (PLD), extreme ultraviolet Colliding Laser-Produced Plasmas Sivanandan S. Harilal, Mathew P. Polek, and Ahmed Hassanein, Member, IEEE Abstract--We report a large jetlike collimated emission feature from colliding laser-produced plasmas (LPPs

Harilal, S. S.

362

Measurement of the W Boson Mass With the Collider Detector at Fermilab  

E-Print Network [OSTI]

Measurement of the W Boson Mass With the Collider Detector at Fermilab A thesis presented by Andrew With the Collider Detector at Fermilab Andrew Scott Gordon Thesis Advisor: Melissa Franklin Abstract We measure at Fermilab from pp collisions at ps = 1800 GeV. The data weretaken from January 1994 through July 1995

Weitz, David

363

DESIGN OF THE MERCURY HANDLING SYSTEM FOR A MUON COLLIDER/NEUTRINO FACTORY TARGET  

E-Print Network [OSTI]

DESIGN OF THE MERCURY HANDLING SYSTEM FOR A MUON COLLIDER/NEUTRINO FACTORY TARGET (IPAC13, THPFI092) The baseline target concept for a Muon Collider or Neutrino Factory is a free mercury jet within a 20-T magnetic field being impacted by an 8-GeV proton beam. A pool of mercury serves as a receiving reservoir

McDonald, Kirk

364

Activation of the liquid helium contamination during its passage in the Collider ring  

SciTech Connect (OSTI)

Radioactivation of possible contamination of the liquid helium trapped in the arcs of the Collider ring of the Superconducting Super Collider and transported by the liquid helium is estimated. This estimation is used to calculate the dose rate on the filter of the refrigerator plant located at the top of the shaft.

Lopez, G.

1994-01-01T23:59:59.000Z

365

Measurement of the Top Quark Mass Simultaneously in Dilepton and Lepton + Jets Decay Channels  

SciTech Connect (OSTI)

The authors present the first measurement of the top quark mass using simultaneously data from two decay channels. They use a data sample of {radical}s = 1.96 TeV collisions with integrated luminosity of 1.9 fb{sup -1} collected by the CDF II detector. They select dilepton and lepton + jets channel decays of t{bar t} pairs and reconstruct two observables in each topology. They use non-parametric techniques to derive probability density functions from simulated signal and background samples. The observables are the reconstructed top quark mass and the scalar sum of transverse energy of the event in the dilepton topology and the reconstructed top quark mass and the invariant mass of jets from the W boson decay in lepton + jets channel. They perform a simultaneous fit for the top quark mass and the jet energy scale which is constrained in situ by the hadronic W boson resonance from the lepton + jets channel. Using 144 dilepton candidate events and 332 lepton + jets candidate events they measure: M{sub top} = 171.9 {+-} 1.7 (stat. + JES) {+-} 1.1 (other sys.) GeV/c{sup 2} = 171.9 {+-} 2.0 GeV/c{sup 2}. The measurement features a robust treatment of the systematic uncertainties, correlated between the two channels and develops techniques for a future top quark mass measurement simultaneously in all decay channels. Measurements of the W boson mass and the top quark mass provide a constraint on the mass of the yet unobserved Higgs boson. The Higgs boson mass implied by measurement presented here is higher than Higgs boson mass implied by previously published, most precise CDF measurements of the top quark mass in lepton + jets and dilepton channels separately.

Fedorko, Wojciech T.; /Chicago U.

2008-09-01T23:59:59.000Z

366

History of Proton Linear Accelerators  

E-Print Network [OSTI]

the board to show why the accelerator couldn't work. Then atmuch. References 1. Linear Accelerators, edited by P. M .at the 1986 Linear Accelerator Conference, SLAC, Stanford,

Alvarez, Luis W.

1986-01-01T23:59:59.000Z

367

Wave functions of linear systems  

E-Print Network [OSTI]

Complete analysis of quantum wave functions of linear systems in an arbitrary number of dimensions is given. It is shown how one can construct a complete set of stationary quantum states of an arbitrary linear system from purely classical arguments. This construction is possible because for linear systems classical dynamics carries the whole information about quantum dynamics.

Tomasz Sowinski

2007-06-05T23:59:59.000Z

368

Theoretical X-ray Line Profiles from Colliding Wind Binaries  

E-Print Network [OSTI]

We present theoretical X-ray line profiles from a range of model colliding wind systems. In particular, we investigate the effects of varying the stellar mass-loss rates, the wind speeds, and the viewing orientation. We find that a wide range of theoretical line profile shapes is possible, varying with orbital inclination and phase. At or near conjunction, the lines have approximately Gaussian profiles, with small widths (HWHM ~ 0.1 v_infty) and definite blue- or redshifts (depending on whether the star with the weaker wind is in front or behind). When the system is viewed at quadrature, the lines are generally much broader (HWHM ~ v_infty), flat-topped and unshifted. Local absorption can have a major effect on the observed profiles - in systems with mass-loss rates of a few times 10^{-6} Msol/yr the lower energy lines (E wind of the primary. The orbital variation ...

Henley, D B; Pittard, J M

2003-01-01T23:59:59.000Z

369

Multifragmentation at the balance energy of mass asymmetric colliding nuclei  

E-Print Network [OSTI]

Using the quantum molecular dynamics model, we study the role of mass asymmetry of colliding nuclei on the fragmentation at the balance energy and on its mass dependence. The study is done by keeping the total mass of the system fixed as 40, 80, 160, and 240 and by varying the mass asymmetry of the ($\\eta$ = $\\frac{A_{T}-A_{P}}{A_{T}+A_{P}}$; where $A_{T}$ and $A_{P}$ are the masses of the target and projectile, respectively) reaction from 0.1 to 0.7. Our results clearly indicate a sizeable effect of the mass asymmetry on the multiplicity of various fragments. The mass asymmetry dependence of various fragments is found to increase with increase in total system mass (except for heavy mass fragments). Similar to symmetric reactions, a power law system mass dependence of various fragment multiplicities is also found to exit for large asymmetries.

Supriya Goyal

2011-06-20T23:59:59.000Z

370

Reducing backgrounds in the higgs factory muon collider detector  

SciTech Connect (OSTI)

A preliminary design of the 125-GeV Higgs Factory (HF) Muon Collider (MC) has identified an enormous background loads on the HF detector. This is related to the twelve times higher muon decay probability at HF compared to that previously studied for the 1.5-TeV MC. As a result of MARS15 optimization studies, it is shown that with a carefully designed protection system in the interaction region, in the machine-detector interface and inside the detector one can reduce the background rates to a manageable level similar to that achieved for the optimized 1.5-TeV case. The main characteristics of the HF detector background are presented for the configuration found.

Mokhov, N. V.; Tropin, I. S.

2014-06-01T23:59:59.000Z

371

Strangelet Search at the BNL Relativistic Heavy Ion Collider  

SciTech Connect (OSTI)

We have searched for strangelets in a triggered sample of 61 million central (top 4percent) Au+Au collisions at sqrt sNN = 200 GeV near beam rapidities at the STAR solenoidal tracker detector at the BNL Relativistic Heavy Ion Collider. We have sensitivity to metastable strangelets with lifetimes of order>_0.1 ns, in contrast to limits over ten times longer in BNL Alternating Gradient Synchrotron (AGS) studies and longer still at the CERN Super Proton Synchrotron (SPS). Upper limits of a few 10-6 to 10-7 per central Au+Au collision are set for strangelets with mass>~;;30 GeV/c2.

Ritter, Ha

2005-11-27T23:59:59.000Z

372

A Staged Muon Accelerator Facility For Neutrino and Collider Physics  

E-Print Network [OSTI]

Muon-based facilities offer unique potential to provide capabilities at both the Intensity Frontier with Neutrino Factories and the Energy Frontier with Muon Colliders. They rely on a novel technology with challenging parameters, for which the feasibility is currently being evaluated by the Muon Accelerator Program (MAP). A realistic scenario for a complementary series of staged facilities with increasing complexity and significant physics potential at each stage has been developed. It takes advantage of and leverages the capabilities already planned for Fermilab, especially the strategy for long-term improvement of the accelerator complex being initiated with the Proton Improvement Plan (PIP-II) and the Long Baseline Neutrino Facility (LBNF). Each stage is designed to provide an R&D platform to validate the technologies required for subsequent stages. The rationale and sequence of the staging process and the critical issues to be addressed at each stage, are presented.

Delahaye, Jean-Pierre; Brice, Stephen; Bross, Alan David; Denisov, Dmitri; Eichten, Estia; Holmes, Stephen; Lipton, Ronald; Neuffer, David; Palmer, Mark Alan; Bogacz, S Alex; Huber, Patrick; Kaplan, Daniel M; Snopok, Pavel; Kirk, Harold G; Palmer, Robert B; Ryne, Robert D

2015-01-01T23:59:59.000Z

373

3-D SPH simulations of colliding winds in eta Carinae  

E-Print Network [OSTI]

We study colliding winds in the superluminous binary eta Carinae by performing three-dimensional, Smoothed Particle Hydrodynamics (SPH) simulations. For simplicity, we assume both winds to be isothermal. We also assume that wind particles coast without any net external forces. We find that the lower density, faster wind from the secondary carves out a spiral cavity in the higher density, slower wind from the primary. Because of the phase-dependent orbital motion, the cavity is very thin on the periastron side, whereas it occupies a large volume on the apastron side. The model X-ray light curve using the simulated density structure fits very well with the observed light curve for a viewing angle of i=54 degrees and phi=36 degrees, where i is the inclination angle and phi is the azimuth from apastron.

Atsuo T. Okazaki; Stanley P. Owocki; Christopher M. P. Russell; Michael F. Corcoran

2008-03-27T23:59:59.000Z

374

The Emerging QCD Frontier: The Electron Ion Collider  

E-Print Network [OSTI]

The self-interactions of gluons determine all the unique features of QCD and lead to a dominant abundance of gluons inside matter already at moderate $x$. Despite their dominant role, the properties of gluons remain largely unexplored. Tantalizing hints of saturated gluon densities have been found in $e$+p collisions at HERA, and in d+Au and Au+Au collisions at RHIC. Saturation physics will have a profound influence on heavy-ion collisions at the LHC. But unveiling the collective behavior of dense assemblies of gluons under conditions where their self-interactions dominate will require an Electron-Ion Collider (EIC): a new facility with capabilities well beyond those In this paper I outline the compelling physics case for $e$+A collisions at an EIC and discuss briefly the status of machine design concepts. of any existing accelerator.

Thomas Ullrich

2008-05-31T23:59:59.000Z

375

The Problem of Colliding Networks and its Relation to Cancer  

E-Print Network [OSTI]

Complex systems, ranging from living cells to human societies, can be represented as attractor networks, whose basic property is to exist in one of allowed states, or attractors. We noted that merging two systems that are in distinct attractors creates uncertainty, as the hybrid system cannot assume two attractors at once. As a prototype of this problem, we explore cell fusion, whose ability to combine distinct cells into hybrids was proposed to cause cancer. By simulating cell types as attractors, we find that hybrids are prone to assume spurious attractors, which are emergent and sporadic states of networks, and propose that cell fusion can make a cell cancerous by placing it into normally inaccessible spurious states. We define basic features of hybrid networks and suggest that the problem of colliding networks has general significance in processes represented by attractor networks, including biological, social, and political phenomena.

Alexei A. Koulakov; Yuri Lazebnik

2012-01-13T23:59:59.000Z

376

Collective Effects in the SuperB Collider  

SciTech Connect (OSTI)

Some collective effects have been studied for the SuperB high luminosity collider. Estimates of the effect of Intra Beam Scattering (IBS) on the emittance and energy spread growths have been carried up for both the High Energy (HER, positrons) and the Low Energy (LER, electrons) rings. Electron cloud build up simulations for HER were performed with the ECLOUD code, developed at CERN, to predict the cloud formation in the arcs, taking into account possible remediation techniques such as clearing electrodes. The new code CMAD, developed at SLAC, has been used to study the effect of this electron cloud on the beam and assess the thresholds above which the electron cloud instability would set in.

Demma, Theo; /INFN, Rome; Pivi, Mauro; /SLAC

2012-06-25T23:59:59.000Z

377

Single Anomalous Production of the Fourth SM Family Quarks at Future e+e-, ep, and pp Colliders  

SciTech Connect (OSTI)

Possible single productions of fourth SM family u4 and d4 quarks via anomalous interactions at the e+e-, ep, and pp colliders are investigated. Signatures of such anomalous processes are discussed at above colliders comparatively.

Ciftci, A. K. [Physics Department, Faculty of Sciences, Ankara University, 06100 Tandogan, Ankara (Turkey); Ciftci, R. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar, Ankara (Turkey); Sultansoy, S. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar, Ankara (Turkey); Institute of Physics, Academy of Sciences, H.Cavid Avenue 33, Baku (Azerbaijan); Yildiz, H. Duran [Physics Department, Faculty of Sciences and Arts, Dumlupinar University, Merkez Kampus, Ankara (Turkey)

2007-04-23T23:59:59.000Z

378

Production Of The ADD Type Kaluza-Klein Excitations At Future e+e-, ep And pp Colliders  

SciTech Connect (OSTI)

Possible production of ADD type Kaluza-Klein excitations are investigated at future high energy e+e-, ep and pp colliders. Discovery limits and signatures of such excitations are discussed at above colliders comparatively.

Billur, A. A.; Ciftci, A. K. [Physics Department, Faculty of Sciences, Ankara University, 06100 Tandogan, Ankara (Turkey); Ciftci, R. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar (Turkey); Inan, S. C. [Physics Department, Faculty of Sciences and Arts, Cumhuriyet University, 58140, Sivas (Turkey); Sultansoy, S. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar (Turkey); Institute of Physics, Academy of Sciences, H. Cavid Avenue 33, Baku (Azerbaijan)

2007-04-23T23:59:59.000Z

379

Production of the Randall-Sundrum Type Kaluza-Klein Excitations at Future e+e-, ep and pp Colliders  

SciTech Connect (OSTI)

Possible production of Randall-Sundrum type Kaluza-Klein excitations are investigated at future high energy e+e-, ep and pp colliders. Discovery limits and signatures of such excitations are discussed at above colliders comparatively.

Billur, A. A.; Ciftci, A. K. [Physics Department, Faculty of Sciences, Ankara University, 06100 Tandogan, Ankara (Turkey); Ciftci, R. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar (Turkey); Inan, S. C. [Physics Department, Faculty of Sciences and Arts, Cumhuriyet University, 58140, Sivas (Turkey); Sultansoy, S. [Physics Department, Faculty of Sciences and Arts, Gazi University, 06500 Teknikokullar (Turkey); Institute of Physics, Academy of Sciences, H. Cavid Avenue 33, Baku (Azerbaijan)

2007-04-23T23:59:59.000Z

380

Atomic mass dependent electrostatic diagnostics of colliding laser plasma plumes  

SciTech Connect (OSTI)

The behaviours of colliding laser plasma plumes (C{sub p}) compared with single plasma plumes (S{sub p}) are investigated for 14 different atomic mass targets. A Faraday cup, situated at the end of a drift tube (L = 0.99 m), is employed to record the time-of-flight (TOF) current traces for all elements and both plume configurations, for a fixed laser intensity of I{sub p} = 4.2 × 10{sup 10} W cm{sup ?2} (F = 0.25 kJ cm{sup ?2}). The ratio of the peak current from the C{sub p} relative to twice that from the S{sub p} is designated as the peak current ratio while the ratio of the integrated charge yield from the C{sub p} relative to twice that from the S{sub p} is designated as the charge yield ratio. Variation of the position of the Faraday cup within the drift tube (L = 0.33, 0.55, and 0.99 m) in conjunction with a lower laser fluence (F = 0.14 kJ cm{sup ?2}) facilitated direct comparison of the changing TOF traces from both plasma configurations for the five lightest elements studied (C, Al, Si, Ti, and Mn). The results are discussed in the frame of laser plasma hydrodynamic modelling to approximate the critical recombination distance L{sub CR}. The dynamics of colliding laser plasma plumes and the atomic mass dependence trends observed are presented and discussed.

Yeates, P. [National Centre for Plasma Science and Technology (NCPST), Dublin City University (DCU), Dublin 7 (Ireland)] [National Centre for Plasma Science and Technology (NCPST), Dublin City University (DCU), Dublin 7 (Ireland); Fallon, C. [School of Physical Sciences, Dublin City University (DCU), Dublin 7 (Ireland)] [School of Physical Sciences, Dublin City University (DCU), Dublin 7 (Ireland); Kennedy, E. T.; Costello, J. T. [National Centre for Plasma Science and Technology (NCPST), Dublin City University (DCU), Dublin 7 (Ireland) [National Centre for Plasma Science and Technology (NCPST), Dublin City University (DCU), Dublin 7 (Ireland); School of Physical Sciences, Dublin City University (DCU), Dublin 7 (Ireland)

2013-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

2005 Final Report: New Technologies for Future Colliders  

SciTech Connect (OSTI)

This document presents an annual report on our long-term R&D grant for development of new technology for future colliders. The organizing theme of our development is to develop a compact high-field collider dipole, utilizing wind-and-react Nb3Sn coil fabrication, stress man-agement, conductor optimization, bladder preload, and flux plate suppression of magnetization multipoles. The development trail for this new technology began over four years ago with the successful testing of TAMU12, a NbTi model in which we put to a first test many of the construction details of the high-field design. We have built TAMU2, a mirror-geometry dipole containing a single coil module of the 3-module set required for the 14 Tesla design. This first Nb3Sn model was built using ITER conductor which carries much less current than high-performance conductor but enables us to prove in practice our reaction bake and impregnation strategies with ‘free’ su-perconductor. TAMU2 has been shipped to LBNL for testing. Work is beginning on the construction of TAMU3, which will contain two coil modules of the 14 Tesla design. TAMU3 has a design field of 13.5 Tesla and will enable us to fully evaluate the issues of stress management that will be important to the full design. With the completion of TAMU2 and the construction of TAMU3 the Texas A&M group ‘comes of age’ in the family of superconducting magnet R&D laboratories. We have completed the phase of developing core technologies and fixtures and entered the phase of building and testing a succession of model dipoles that each build incrementally upon a proven core design.

Peter McIntyre; Al McInturff

2005-12-31T23:59:59.000Z

382

IR OPTICS MEASUREMENT WITH LINEAR COUPLING'S ACTION-ANGLE PARAMETERIZATION.  

SciTech Connect (OSTI)

A parameterization of linear coupling in action-angle coordinates is convenient for analytical calculations and interpretation of turn-by-turn (TBT) beam position monitor (BPM) data. We demonstrate how to use this parameterization to extract the twiss and coupling parameters in interaction regions (IRs), using BPMs on each side of the long IR drift region. The example of TBT BPM analysis was acquired at the Relativistic Heavy Ion Collider (RHIC), using an AC dipole to excite a single eigenmode. Besides the full treatment, a fast estimate of beta*, the beta function at the interaction point (IP), is provided, along with the phase advance between these BPMs. We also calculate and measure the waist of the beta function and the local optics.

LUO, Y.; BAI, M.; PILAT, R.; SATOGATA, T.; TRBOJEVIC, D.

2005-05-16T23:59:59.000Z

383

A Search for Prompt Lepton-Jets in pp Collisions at ?s = 7 TeV with the ATLAS Detector  

E-Print Network [OSTI]

We present a search for a light (<2 GeV) boson predicted by Hidden Valley supersymmetric models that decays into a final state consisting of collimated muons or electrons, denoted “lepton-jets”. The analysis uses 5 ...

Taylor, Frank E.

384

Electric dipole moments of charged leptons in the split fermion scenario in the two Higgs doublet model  

E-Print Network [OSTI]

We predict the charged lepton electric dipole moments in the split fermion scenario in the framework of the two Higgs doublet model. We observe that the numerical value of the muon (tau) electric dipole moment is at the order of the magnitude of $10^{-22} (e-cm)$ ($10^{-20} (e-cm)$) and there is an enhancement in the case of two extra dimensions, especially for the tau lepton electric dipole moment.

E. O. Iltan

2005-09-24T23:59:59.000Z

385

CPT and lepton number violation in neutrino sector: Modified mass matrix and oscillation due to gravity  

E-Print Network [OSTI]

We study the consequences of CPT and lepton number violation in neutrino sector. For CPT violation we take gravity with which neutrino and antineutrino couple differently. Gravity mixes neutrino and antineutrino in an unequal ratio to give two mass eigenstates. Lepton number violation interaction together with CPT violation gives rise to neutrino-antineutrino oscillation. Subsequently, we study the neutrino flavor mixing and oscillation under the influence of gravity. It is found that gravity changes flavor oscillation significantly which influences the relative abundance of different flavors in present universe. We show that the neutrinoless double beta decay rate is modified due to presence of gravity- the origin of CPT violation, as the mass of the flavor state is modified.

Monika Sinha; Banibrata Mukhopadhyay

2007-11-21T23:59:59.000Z

386

A model of leptons, quarks and bosons as composites of spinons  

E-Print Network [OSTI]

A model is presented of the leptons, quarks and bosons as non-elementary particles being composed of spinons. They are defined as massless fermions obeying the Weyl equations, but in addition are charged and assumed to have two internal degrees of freedom (weak colour charges). The corresponding total Lagrangian density of the quantized fields has a fermionic part and a gauge-field part, which leads to the interaction of the charged spinons. They are bound together by the gauge fields of the non-Abelian SU(2) symmetry group, and three of them can combine to a triple state forming the well known first generation of left- and right-handed leptons and quarks, including their proper electric charges (fractional for the quarks). The neutral and charged vector bosons of the weak interactions or the Higgs bosons can be constructed as binaries of two spinons.

Eckart Marsch

2010-04-20T23:59:59.000Z

387

An infrared origin of leptonic mixing and its test at DeepCore  

E-Print Network [OSTI]

Fermion mixing is generally believed to be a low-energy manifestation of an underlying theory whose energy scale is much larger than the electroweak scale. In this paper we investigate the possibility that the parameters describing lepton mixing actually arise from the low-energy behavior of the neutrino interacting fields. In particular, we conjecture that the measured value of the mixing angles for a given process depends on the number of unobservable flavor states at the energy of the process. We provide a covariant implementation of such conjecture, draw its consequences in a two neutrino family approximation and compare these findings with current experimental data. Finally we show that this infrared origin of mixing will be manifest at the Ice Cube DeepCore array, which measures atmospheric oscillations at energies much larger than the tau lepton mass; it will hence be experimentally tested in a short time scale.

F. Terranova

2011-10-10T23:59:59.000Z

388

Events with Isolated Leptons and Missing Transverse Momentum and Measurement of W Production at HERA  

E-Print Network [OSTI]

Events with high energy isolated electrons, muons or tau leptons and missing transverse momentum are studied using the full e^\\pm p data sample collected by the H1 experiment at HERA, corresponding to an integrated luminosity of 474 pb^{-1}. Within the Standard Model, events with isolated leptons and missing transverse momentum mainly originate from the production of single W bosons. The total single W boson production cross section is measured as 1.14 \\pm 0.25 (stat.) \\pm 0.14 (sys.) pb, in agreement with the Standard Model expectation. The data are also used to establish limits on the WW\\gamma gauge couplings and for a measurement of the W boson polarisation.

Aaron, F D; Andreev, V; Antunovic, B; Aplin, S; Asmone, A; Astvatsatourov, A; Backovic, S; Baghdasaryan, A; Barrelet, E; Bartel, W; Begzsuren, K; Behnke, O; Belousov, A; Bizot, J C; Boudry, V; Bozovic-Jelisavcic, I; Bracinik, J; Brandt, G; Brinkmann, M; Brisson, V; Bruncko, D; Bunyatyan, A; Buschhorn, G; Bystritskaya, L; Campbell, A J; Cantun Avila, K B; Cassol-Brunner, F; Cerny, K; Cerny, V; Chekelian, V; Cholewa, A; Contreras, J G; Coughlan, J A; Cozzika, G; Cvach, J; Dainton, J B; Daum, K; Deak, M; de Boer, Y; Delcourt, B; Del Degan, M; Delvax, J; De Roeck, A; De Wolf, E A; Diaconu, C; Dodonov, V; Dossanov, A; Dubak, A; Eckerlin, G; Efremenko, V; Egli, S; Eliseev, A; Elsen, E; Essenov, S; Falkiewicz, A; Faulkner, P J W; Favart, L; Fedotov, A; Felst, R; Feltesse, J; Ferencei, J; Fischer, D J; Fleischer, M; Fomenko, A; Gabathuler, E; Gayler, J; Ghazaryan, S; Glazov, A; Glushkov, I; Goerlich, L; Goettlich, M; Gogitidze, N; Gouzevitch, M; Grab, C; Greenshaw, T; Grell, B R; Grindhammer, G; Habib, S; Haidt, D; Hansson, M; Helebrant, C; Henderson, R C W; Hennekemper, E; Henschel, H; Herrera, G; Hildebrandt, M; Hiller, K H; Hoffmann, D; Horisberger, R; Hreus, T; Jacquet, M; Janssen, M E; Janssen, X; Jemanov, V; Jonsson, L; Jung, Andreas Werner; Jung, H; Kapichine, M; Katzy, J; Kenyon, I R; Kiesling, C; Klein, M; Kleinwort, C; Klimkovich, T; Kluge, T; Knutsson, A; Kogler, R; Korbel, V; Kostka, P; Kraemer, M; Krastev, K; Kretzschmar, J; Kropivnitskaya, A; Kruger, K; Kutak, K; Landon, M.P J; Lange, W; Lastovicka-Medin, G; Laycock, P; Lebedev, A; Leibenguth, G; Lendermann, V; Levonian, S; Li, G; Lipka, K; Liptaj, A; List, B; List, J; Loktionova, N; Lopez-Fernandez, R; Lubimov, V; Lytkin, L; Makankine, A; Malinovski, E; Marage, P; Marti, Ll; Martyn, H.-U; Maxfield, S J; Mehta, A; Meier, K; Meyer, A B; Meyer, H; Meyer, H; Meyer, J; Michels, V; Mikocki, S; Milcewicz-Mika, I; Moreau, F; Morozov, A; Morris, J V; Mozer, Matthias Ulrich; Mudrinic, M; Muller, K; Murin, P; Naroska, B; Naumann, Th; Newman, P R; Niebuhr, C; Nikiforov, A; Nowak, G; Nowak, K; Nozicka, M; Olivier, B; Olsson, J E; Osman, S; Ozerov, D; Palichik, V; Panagoulias, I; Pandurovic, M; Papadopoulou, Th; Pascaud, C; Patel, G D; Pejchal, O; Perez, E; Petrukhin, A; Picuric, I; Piec, S; Pitzl, D; Placakyte, R; Polifka, R; Povh, B; Preda, T; Radescu, V; Rahmat, A J; Raicevic, N; Raspiareza, A; Ravdandorj, T; Reimer, P; Rizvi, E; Robmann, P; Roland, B; Roosen, R; Rostovtsev, A; Rotaru, M; Ruiz Tabasco, J E; Rurikova, Z; Rusakov, S; Salek, D; Sankey, D P C; Sauter, M; Sauvan, E; Schmitt, S; Schmitz, C; Schoeffel, L; Schoning, A; Schultz-Coulon, H C; Sefkow, F; Shaw-West, R N; Sheviakov, I; Shtarkov, L N; Shushkevich, S; Sloan, T; Smiljanic, Ivan; Soloviev, Y; Sopicki, P; South, D; Spaskov, V; Specka, Arnd E; Staykova, Z; Steder, M; Stella, B; Stoicea, G; Straumann, U; Sunar, D; Sykora, T; Tchoulakov, V; Thompson, G; Thompson, P D; Toll, T; Tomasz, F; Tran, T H; Traynor, D; Trinh, T N; Truol, P; Tsakov, I; Tseepeldorj, B; Turnau, J; Urban, K; Valkarova, A; Vallee, C; Van Mechelen, P; Vargas Trevino, A; Vazdik, Y; Vinokurova, S; Volchinski, V; Wegener, D; Wissing, Ch; Wunsch, E; Zacek, J; Zalesak, J; Zhang, Z; Zhokin, A; Zimmermann, T; Zohrabyan, H; Zomer, F; 10.1140/epjc/s10052-009-1160-6

2009-01-01T23:59:59.000Z

389

Winding for linear pump  

DOE Patents [OSTI]

A winding and method of winding for a submersible linear pump for pumping liquid sodium is disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet.

Kliman, Gerald B. (Schenectady, NY); Brynsvold, Glen V. (San Jose, CA); Jahns, Thomas M. (Schenectady, NY)

1989-01-01T23:59:59.000Z

390

On leptonic decay of a heavy quarkonium with a Higgs-boson emission  

E-Print Network [OSTI]

A leptonic $(\\bar l l)$ decay of a heavy quark-antiquark bound state $T(\\bar QQ)$ with a Higgs-boson $H$ emission is investigated. The applying of the well-known low-energy theorem to meson-Higgs coupling allows one to estimate the probability of the decay $T(\\bar QQ)\\to \\bar ll H$. The only a simple version of the Standard Model extension containing two-Higgs doublet is considered.

G. A. Kozlov

2005-06-27T23:59:59.000Z

391

Search for the associated production of chargino and neutralino in the final state with three leptons  

SciTech Connect (OSTI)

Supersymmetry, if realized in nature, predicts the existence of new particles, as chargino and neutralino, which might manifest themselves with peculiar signatures. Three leptons and large missing transverse energy in the event could signal their associated production. They report the latest results of the search performed by the CDF Collaboration in {radical}s = 1.96 TeV proton-antiproton collisions at Tevatron Run II.

Canepa, Anadi; /Purdue U.

2006-02-01T23:59:59.000Z

392

PoS(EPS-HEP2013)326 Measurement of the ratio of the leptonic widths  

E-Print Network [OSTI]

PoS(EPS-HEP2013)326 Measurement of the ratio of the leptonic widths ee/µµ for the J/ V. M. The European Physical Society Conference on High Energy Physics EPS-HEP2013 18-24 July 2013 Stockholm, Sweden-NonCommercial-ShareAlike Licence. http://pos.sissa.it/ #12;PoS(EPS-HEP2013)326 ee(J/)/µµ (J/) measurement E. M. Baldin 1 2 3 4 5 6

393

The physics of kaon decays: CP violation and lepton flavor nonconservation  

SciTech Connect (OSTI)

OAK B188 The physics of kaon decays: CP violation and lepton flavor nonconservation. We discuss here the research that is likely to be done in the 1990's in the study of kaon decays. We concentrate on searches for direct CP violation and for the violation of electron- and muon-number, including approved and proposed experiments at existing facilities, and those which could be done at a facility using the proposed Fermilab Main Injector.

William R. Molzon; Bruce D. Winstein

1992-04-30T23:59:59.000Z

394

Precision Measurement of the Ratio of the Charged Kaon Leptonic Decay Rates  

E-Print Network [OSTI]

A precision measurement of the ratio RK of the rates of kaon leptonic decays K+- --> e nu and K+- --> mu nu with the full data sample collected by the NA62 experiment at CERN in 2007-2008 is reported. The result, obtained by analysing ~150000 reconstructed K+- --> e nu candidates with 11% background contamination, is RK = (2.488+-0.010)*10^{-5}, in agreement with the Standard Model expectation.

The NA62 collaboration

2013-01-29T23:59:59.000Z

395

Search for Lepton Number Violating Charged Current Processes with Neutrino Beams  

E-Print Network [OSTI]

We propose a new idea to test a class of loop-induced neutrino mass mechanisms by searching for lepton number violating charged current processes with incident of a neutrino beam. The expected rates of these processes are estimated based on some theoretical assumptions. They turn out to be sizable so that detection of such processes could be possible at near detectors in future highly intense neutrino-beam facilities.

Shinya Kanemura; Yoshitaka Kuno; Toshihiko Ota

2012-05-25T23:59:59.000Z

396

Linear equalities in blackbox optimization ?  

E-Print Network [OSTI]

May 28, 2014 ... extensions to treat problems with linear equalities whose expression is known. The main idea consists in reformulating the optimization ...

Mathilde Peyrega

2014-05-28T23:59:59.000Z

397

Quantization of general linear electrodynamics  

SciTech Connect (OSTI)

General linear electrodynamics allow for an arbitrary linear constitutive relation between the field strength 2-form and induction 2-form density if crucial hyperbolicity and energy conditions are satisfied, which render the theory predictive and physically interpretable. Taking into account the higher-order polynomial dispersion relation and associated causal structure of general linear electrodynamics, we carefully develop its Hamiltonian formulation from first principles. Canonical quantization of the resulting constrained system then results in a quantum vacuum which is sensitive to the constitutive tensor of the classical theory. As an application we calculate the Casimir effect in a birefringent linear optical medium.

Rivera, Sergio; Schuller, Frederic P. [Albert Einstein Institute, Max Planck Institute for Gravitational Physics, Am Muehlenberg 1, 14476 Potsdam (Germany)

2011-03-15T23:59:59.000Z

398

The role of Spectator Fragments at an electron Ion collider  

E-Print Network [OSTI]

Efficient detection of spectator fragments is key to the main topics at an electron-ion collider (eIC). Any process which leads to emission of fragments or $\\gamma$'s breaks coherence in diffractive processes. Therefore this is equivalent to non-detection of rapidity gaps in pp collisions. For example, in coherent photoproduction of vector mesons their 4-momentum transfer distribution would image the "gluon charge" in the nucleus in the same way that Hofstadter measured its charge structure using elastic scattering of $\\sim$100 MeV electrons. Whereas he could measure the $\\sim$4 MeV energy loss by the electron due to excitation of nuclear energy levels (Figure 1), even the energy spread of the incident beam would prevent such an inclusive selection of quasielastic events at an eIC. The only available tool is fragment detection. Since, in our example, one finds that $\\sim100$ of deexcitations go through $\\gamma$'s or 1 neutron, rarely to 2 neutron and never to protons(due to Coulomb barrier suppression), the eIC design should emphasize their detection.

Sebastian White; Mark Strikman

2010-03-10T23:59:59.000Z

399

Large hadron collider (LHC) project quality assurance plan  

SciTech Connect (OSTI)

The LHC Quality Assurance Plan is a set of operating principles, requirements, and practices used to support Berkeley Lab's participation in the Large Hadron Collider Project. The LHC/QAP is intended to achieve reliable, safe, and quality performance in the LHC project activities. The LHC/QAP is also designed to fulfill the following objectives: (1) The LHC/QAP is Berkeley Lab's QA program document that describes the elements necessary to integrate quality assurance, safety management, and conduct of operations into the Berkeley Lab's portion of the LHC operations. (2) The LHC/QAP provides the framework for Berkeley Lab LHC Project administrators, managers, supervisors, and staff to plan, manage, perform, and assess their Laboratory work. (3) The LHC/QAP is the compliance document that conforms to the requirements of the Laboratory's Work Smart Standards for quality assurance (DOE O 414.1, 10 CFR 830.120), facility operations (DOE O 5480.19), and safety management (DOE P 450.4).

Gullo, Lisa; Karpenko, Victor; Robinson, Kem; Turner, William; Wong, Otis

2002-09-30T23:59:59.000Z

400

First electron-cloud studies at the Large Hadron Collider  

E-Print Network [OSTI]

During the beam commissioning of the Large Hadron Collider (LHC) with 150, 75, 50, and 25-ns bunch spacing, important electron-cloud effects, like pressure rise, cryogenic heat load, beam instabilities, or emittance growth, were observed. Methods have been developed to infer different key beam-pipe surface parameters by benchmarking simulations and pressure rise as well as heat-load observations. These methods allow us to monitor the scrubbing process, i.e., the reduction of the secondary emission yield as a function of time, in order to decide on the most appropriate strategies for machine operation. To better understand the influence of electron clouds on the beam dynamics, simulations have been carried out to examine both the coherent and the incoherent effects on the beam. In this paper we present the methodology and first results for the scrubbing monitoring process at the LHC. We also review simulated instability thresholds and tune footprints for beams of different emittance, interacting with an electr...

Dominguez, O; Arduini, G; Metral, E; Rumolo, G; Zimmermann, F; Maury Cuna, H

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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401

Theoretical X-ray Line Profiles from Colliding Wind Binaries  

E-Print Network [OSTI]

We present theoretical X-ray line profiles from a range of model colliding wind systems. In particular, we investigate the effects of varying the stellar mass-loss rates, the wind speeds, and the viewing orientation. We find that a wide range of theoretical line profile shapes is possible, varying with orbital inclination and phase. At or near conjunction, the lines have approximately Gaussian profiles, with small widths (HWHM ~ 0.1 v_\\infty) and definite blue- or redshifts (depending on whether the star with the weaker wind is in front or behind). When the system is viewed at quadrature, the lines are generally much broader (HWHM ~ v_\\infty), flat-topped and unshifted. Local absorption can have a major effect on the observed profiles - in systems with mass-loss rates of a few times 10^{-6} Msol/yr the lower energy lines (E wind of the primary. The orbital variation of the line widths and shifts is reduced in a low inclination binary. The extreme case is a binary with i = 0 degrees, for which we would expect no line profile variation.

D. B. Henley; I. R. Stevens; J. M. Pittard

2003-06-23T23:59:59.000Z

402

Hydrodynamics and High-Energy Physics of WR Colliding Winds  

E-Print Network [OSTI]

One of the main properties of Wolf-Rayet (WR) stars is a very intense outflow of gas. No less than 40\\% \\ of WR stars belong to binary systems. Young massive O and B stars are the secondary components of such systems. OB stars also have an intense stellar wind. If the intensities of the stellar winds of WR and OB stars are more or less comparable or if the distance between the components of the binary is large enough, the winds flowing out of WR and OB stars can collide and the shock waves are formed. In the shock the gas is heated to temperature $\\sim 10^7$ K and generates X-ray emission. Stellar wind collision may be responsible not only for the X-ray emission of WR + OB binaries and for their radio, IR and $\\gamma$-ray emision as well. Stellar wind collision, gas heating, particle acceleration, and generation of X-ray, $\\gamma$-ray, radio and IR emission in WR + OB binaries are discussed.

Vladimir V. Usov

1994-05-29T23:59:59.000Z

403

Muon Collider Final Cooling in 30-50 T Solenoids  

SciTech Connect (OSTI)

Muon ionization cooling to the required normalized rms emittance of 25 microns transverse, and 72 mm longitudinal, can be achieved with liquid hydrogen in high field solenoids, provided that the momenta are low enough. At low momenta, the longitudinal emittance rises from the negative slope of energy loss versus energy. Assuming initial emittances that have been achieved in six dimensional cooling simulations, optimized designs are given using solenoid fields limited to 30, 40, and 50 T. The required final emittances are achieved for the two higher field cases. Preliminary simulations of transverse cooling in hydrogen, at low energies, suggests that muon collider emittance requirements can be met using solenoid fields of 40 T or more. It might also be acceptable with 30 T. But these simulations did not include hydrogen windows,matching or reacceleration, whose performance, with one exception, was based on numerical estimates. Full simulations of more stages are planned. The design and simulation of hydrogen windows must be included, and space charge effects, and absorber heating, calculated.

Palmer, R.B.; Fernow, R.C.; Lederman, J.

2011-03-28T23:59:59.000Z

404

Search for supersymmetry via associated production of charginos and neutralinos in final states with three leptons  

E-Print Network [OSTI]

A search for associated production of charginos and neutralinos is performed using data recorded with the D0 detector at a p (p) over bar center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. This analysis ...

Baringer, Philip S.; Bean, Alice; Christofek, L.; Coppage, Don; Gardner, J.; Hensel, Carsten; Jabeen, S.; Wilson, Graham Wallace

2005-10-01T23:59:59.000Z

405

Design of High Luminosity Ring-Ring Electron- Light Ion Collider at CEBAF  

SciTech Connect (OSTI)

Experimental studies of fundamental structure of nucleons require an electron-ion collider of a center-of-mass energy up to 90 GeV at luminosity up to 1035 cm-2s-1 with both beams polarized. A CEBAF-based collider of 9 GeV electrons/positrons and 225 GeV ions is envisioned to meet this science need and as a next step for CEBAF after the planned 12 GeV energy upgrade of the fixed target program. A ring-ring scheme of this collider developed recently takes advantage of the existing polarized electron CW beam from the CEBAF and a green-field design of an ion complex with electron cooling. We present a conceptual design and report design studies of this high-luminosity collider.

Slawomir Bogacz; Antje Bruell; Jean Delayen; Yaroslav Derbenev; Rolf Ent; Joseph Grames; Andrew Hutton; Geoffrey Krafft; Rui Li; Nikolitsa Merminga; Benard Poelker; Bogdan Wojtsekhowski; Byung Yunn; Yuhong Zhang; C Montag

2007-06-25T23:59:59.000Z

406

SciTech Connect: Proton-Proton Colliding-Beam Storage Rings for...  

Office of Scientific and Technical Information (OSTI)

future plans can be based. It is to be emphasized that this is not a proposal for construction. The major results of the study are that 100-100 BeV colliding beam rings can be...

407

Search for new light gauge boson in Higgs boson decays to four-lepton events in pp collisions at 8 TeV with the ATLAS detector  

E-Print Network [OSTI]

Search for new light gauge boson in Higgs boson decays to four-lepton events in pp collisions at 8 TeV with the ATLAS detector

Paredes Hernandez, Daniela; The ATLAS collaboration

2015-01-01T23:59:59.000Z

408

Search for new light gauge bosons in Higgs boson decays to four-lepton final states in $pp$ collisions at $\\sqrt{s}=8~$TeV with the ATLAS detector at the LHC.  

E-Print Network [OSTI]

This paper presents a search for Higgs bosons decaying to four leptons via one or two light exotic gauge bosons $Z_d$, $H\\to Z Z_d \\to 4\\ell$ and $H \\to Z_dZ_d \\to 4\\ell$ ($\\ell=e$ or $\\mu$). The search is performed using $pp$ collision data corresponding to an integrated luminosity of about 20~\\ifb\\ at the center-of-mass energy of $\\sqrt{s}=8~$TeV recorded with the ATLAS detector at the Large Hadron Collider. The observed data are well described by the Standard Model prediction. Upper bounds at 95\\% confidence level are set on the relative branching ratios $BR(H \\to ZZ_d\\to 4\\ell)$ to $BR(H \\to 4\\ell)$ for the exotic vector boson masses between 15 and 55~GeV, and $BR(H \\to Z_dZ_d \\to 4\\ell)$ to $BR(H \\to ZZ^* \\to 4\\ell)$ for the exotic vector boson masses between 15 and 60~GeV.

The ATLAS collaboration

2015-01-01T23:59:59.000Z

409

MIXED INTEGER LINEAR PROGRAMMING FORMULATION ...  

E-Print Network [OSTI]

Jul 22, 2014 ... multi-commodity network flow problem with piecewise linear costs. ...... [82] IBM ILOG, CPLEX High-performance mathematical programming engine. .... Scheduling of Public Transport Urban Passenger Vehicle and Crew ...

2014-07-22T23:59:59.000Z

410

Linear actuator powered flapping wing  

E-Print Network [OSTI]

Small scale unmanned aerial vehicles (UAVs) have proven themselves to be useful, but often too noisy for certain operations due to their rotary motors. This project examined the feasibility of using an almost silent linear ...

Benson, Christopher Lee

2010-01-01T23:59:59.000Z

411

A linear induction motor conveyer  

E-Print Network [OSTI]

A LINEAR INCUCTION MOTOR CONVEYER A Thesis Kenneth Sheldon. Solinsky Submitted to the Graduate College of Texas AkM University in partial fulfillment of the requirement for the degree of MASTER 07 SCIENCE May 1973 Major Subject: Industrial.... Howie, USAMC-ITC-P/P, Red River Army Depot, Texarkana, Texas 75501. Approved owxe, xe , ro uc o uction Engineering For the Commander ne , grec or, I A LINEAR INDUCTION MOTOR CONVEYER A Thesis by Kenneth Sheldon Solinsky App ved as to style...

Solinsky, Kenneth Sheldon

1973-01-01T23:59:59.000Z

412

Effect of steriles states on lepton magnetic moments and neutrinoless double beta decay  

E-Print Network [OSTI]

We address the impact of sterile fermion states on the anomalous magnetic moment of charged leptons, as well as their contribution to neutrinoless double beta decays. We illustrate our results in a minimal, effective extension of the Standard Model by one sterile fermion state, and in a well-motivated framework of neutrino mass generation, embedding the Inverse Seesaw into the Standard Model. The simple "3+1" effective case succeeds in alleviating the tension related to the muon anomalous magnetic moment, albeit only at the 3$\\sigma$ level, and for light sterile states (corresponding to a }cosmologically disfavoured regime). Interestingly, our analysis shows that a future $0 \

Abada, A; Teixeira, A M

2014-01-01T23:59:59.000Z

413

AN in inclusive lepton-proton collisions: TMD and twist-3 approaches  

SciTech Connect (OSTI)

We consider the inclusive production of hadrons in lepton-nucleon scattering. For a transversely polarized nucleon this reaction shows a left-right azimuthal asymmetry, which we compute this asymmetry in both TMD and in twist-3 collinear factorization formalisms. All non-perturbative parton correlators of the calculation are fixed through information from other hard processes. Our results for the left-right asymmetry agree in sign with recent data for charged pion production from the HERMES Collaboration and from Jefferson Lab. We discuss similarities and differences of two formalisms.

Prokudin, Alexey [JLAB

2015-01-01T23:59:59.000Z

414

Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector  

E-Print Network [OSTI]

Results of a search for $H \\to \\tau \\tau$ decays are presented, based on the full set of proton--proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 $\\rm{fb}^{-1}$ and 20.3 $\\rm{fb}^{-1}$ at centre-of-mass energies of $\\sqrt{s}$ = 7 TeV and $\\sqrt{s}$ = 8 TeV respectively. All combinations of leptonic ($\\tau \\to \\ell \

Aad, Georges; ATLAS Collaboration; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; ?lvarez Piqueras, Damián; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Arabidze, Giorgi; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, Bradley; Azuelos, Georges; Azuma, Yuya; Baak, Max; Baas, Alessandra; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Badescu, Elisabeta; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Balek, Petr; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Bartsch, Valeria; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beacham, James Baker; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Katharina; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Beringer, Jürg; Bernard, Clare; Bernard, Nathan Rogers; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertsche, Carolyn; Bertsche, David; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bevan, Adrian John; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien

2015-01-01T23:59:59.000Z

415

Preservation and control of the proton and deuteron polarizations in the proposed electron-ion collider at Jefferson Lab  

SciTech Connect (OSTI)

We propose a scheme of preserving the proton and deuteron beam polarizations during acceleration and storage in the proposed electron-ion collider at Jefferson Lab. This scheme allows one to provide both the longitudinal and transverse polarization orientations of the proton and deuteron beams at the interaction points of the figure-8 ion collider ring. We discuss questions of matching the polarization direction at all stages of the beam transport including the pre-booster, large booster and ion collider ring.

Kondratenko, Anatoliy [Scientific and Technical Laboratory Zaryad, Novosibirsk (Russian Federation); Derbenev, Yaroslav S. [JLAB, Newport News, VA (United States); Filatov, Yury [Moscow Institute of Physics and Technology, Dolgoprudny (Russian Federation); Lin, Fanglei [JLAB, Newport News, VA (United States); Morozov, Vasiliy [JLAB, Newport News, VA (United States); Kondratenko, M. A. [Scientific and Technical Laboratory Zaryad, Novosibirsk (Russian Federation); Zhang, Yuhong [JLAB, Newport News, VA (United States)

2014-01-01T23:59:59.000Z

416

Disbursement of $65 million to the State of Texas for construction of a Regional Medical Technology Center at the former Superconducting Super Collider Site, Waxahachie, Texas  

SciTech Connect (OSTI)

As part of a settlement agreement between the US DOE and the State of Texas, DOE proposes to transfer $65 million of federal funds to the Texas National Research Laboratory Commission (TNLRC) for construction of the Regional Medical Technology Center (RMTC) to be located in Ellis County, Texas. The RMTC would be a state-of-the-art medical facility for proton cancer therapy, operated by the State of Texas in conjunction with the University of Texas Southwestern Medical Center. The RMTC would use the linear accelerator assets of the recently terminated DOE Superconducting Super Collider Project to accelerate protons to high energies for the treatment of cancer patients. The current design provides for treatment areas, examination rooms, support laboratories, diagnostic imaging equipment, and office space as well as the accelerators (linac and synchrotron) and beam steering and shaping components. The potential environmental consequences of the proposed action are expected to be minor.

NONE

1995-05-01T23:59:59.000Z

417

Test of Lepton Universality in Upsilon(1S) Decays at BaBar  

SciTech Connect (OSTI)

The ratio R{sub {tau}{mu}}({Upsilon}(1S))={Lambda}{sub {Upsilon}(1S){yields}{tau}{sup +}{tau}{sup -}}/{Lambda}{sub {Upsilon}(1S){yields}{mu}{sup +}{mu}{sup -}} is measured using a sample of (121.8 {+-} 1.2) x 10{sup 6}{Upsilon}(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays {Upsilon}(3S) {yields} {Upsilon}(1S){sub {pi}{sup +}{pi}{sup -}}, {Upsilon}(1S) {yields} {ell}{sup +}{ell}{sup -}, where l = {mu}, {tau}. The result, R{sub {tau}{mu}}({Upsilon}(1S))=1.005 {+-} 0.013(stat) {+-} 0.022(syst), shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, David Nathan; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Columbus Supercond., Genova /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U.; /more authors.; ,

2010-06-07T23:59:59.000Z

418

Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions  

SciTech Connect (OSTI)

A search for neutral Higgs bosons in the minimal supersymmetric extension of the standard model (MSSM) decaying to tau-lepton pairs in pp collisions is performed, using events recorded by the CMS experiment at the LHC. The dataset corresponds to an integrated luminosity of 24.6 fb$^{?1}$, with 4.9 fb$^{?1}$ at 7 TeV and 19.7 fb$^{?1}$ at 8 TeV. To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes the case where the Higgs boson is produced in association with a b-quark jet. No excess is observed in the tau-lepton-pair invariant mass spectrum. Exclusion limits are presented in the MSSM parameter space for different benchmark scenarios, m$_{h}^{max}$ , m$_{h}^{mod?+}$ , m$_{h}^{mod??}$ , light-stop, light-stau, ?-phobic, and low-m$_{H}$. Upper limits on the cross section times branching fraction for gluon fusion and b-quark associated Higgs boson production are also given.

Khachatryan, V. [Yerevan Physics Institute (Armenia); et al.,

2014-10-01T23:59:59.000Z

419

NLO QCD and electroweak corrections to W+? production with leptonic W-boson decays  

E-Print Network [OSTI]

We present a calculation of the next-to-leading-order electroweak corrections to W+\\gamma\\ production, including the leptonic decay of the W boson and taking into account all off-shell effects of the W boson, where the finite width of the W boson is implemented using the complex-mass scheme. Corrections induced by incoming photons are fully included and find particular emphasis in the discussion of phenomenological predictions for the LHC. The corresponding next-to-leading-order QCD corrections are reproduced as well. In order to separate hard photons from jets, a quark-to-photon fragmentation function a la Glover and Morgan is employed. Our results are implemented into Monte Carlo programs allowing for the evaluation of arbitrary differential cross sections. We present integrated cross sections for the LHC at 7TeV, 8TeV, and 14TeV as well as differential distributions at 14TeV for bare muons and dressed leptons. Finally, we discuss the impact of anomalous WW\\gamma\\ couplings.

Ansgar Denner; Stefan Dittmaier; Markus Hecht; Christian Pasold

2014-12-23T23:59:59.000Z

420

Effective Hamiltonian for non-leptonic |Delta F| = 1 decays at NNLO in QCD  

SciTech Connect (OSTI)

The authors compute the effective hamiltonian for non-leptonic |{Delta}F| = 1 decays in the standard model including next-to-next-to-leading order QCD corrections. In particular, they present the complete three-loop anomalous dimension matrix describing the mixing of current-current and QCD penguin operators. The calculation is performed in an operator basis which allows to consistently use fully anticommuting {gamma}{sub 5} in dimensional regularization at an arbitrary number of loops. The renormalization scheme dependences and their cancellation in physical quantities is discussed in detail. Furthermore, they demonstrate how the results are transformed to a different basis of effective operators which is frequently adopted in phenomenological applications. They give all necessary two-loop constant terms which allow to obtain the three-loop anomalous dimensions and the corresponding initial conditions of the two-loop Wilson coefficients in the latter scheme. Finally, they solve the renormalization group equation and given the analytic expressions for the low-energy Wilson coefficients relevant for non-leptonic B meson decays beyond next-to-leading order in both renormalization schemes.

Gorbahn, Martin; /Durham U., IPPP; Haisch, Ulrich; /Fermilab

2004-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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421

Low and high energy phenomenology of quark-lepton complementarity scenarios  

SciTech Connect (OSTI)

We conduct a detailed analysis of the phenomenology of two predictive seesaw scenarios leading to quark-lepton complementarity. In both cases we discuss the neutrino mixing observables and their correlations, neutrinoless double beta decay and lepton flavor violating decays such as {mu}{yields}e{gamma}. We also comment on leptogenesis. The first scenario is disfavored on the level of one to two standard deviations, in particular, due to its prediction for |U{sub e3}|. There can be resonant leptogenesis with quasidegenerate heavy and light neutrinos, which would imply sizable cancellations in neutrinoless double beta decay. The decays {mu}{yields}e{gamma} and {tau}{yields}{mu}{gamma} are typically observable unless the SUSY masses approach the TeV scale. In the second scenario leptogenesis is impossible. It is, however, in perfect agreement with all oscillation data. The prediction for {mu}{yields}e{gamma} is in general too large, unless the SUSY masses are in the range of several TeV. In this case {tau}{yields}e{gamma} and {tau}{yields}{mu}{gamma} are unobservable.

Hochmuth, Kathrin A. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Munich (Germany); Rodejohann, Werner [Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, D-85748 Garching (Germany)

2007-04-01T23:59:59.000Z

422

Updated fit to three neutrino mixing: status of leptonic CP violation  

E-Print Network [OSTI]

We present a global analysis of solar, atmospheric, reactor and accelerator neutrino data in the framework of three-neutrino oscillations based on data available in summer 2014. We provide the allowed ranges of the six oscillation parameters and show that their determination is stable with respect to uncertainties related to reactor neutrino and solar neutrino flux predictions. We find that the maximal possible value of the Jarlskog invariant in the lepton sector is $0.0329 \\pm 0.0009$ ($\\pm 0.0027$) at the $1\\sigma$ ($3\\sigma$) level and we use leptonic unitarity triangles to illustrate the ability of global oscillation data to obtain information on CP violation. We discuss "tendencies and tensions" of the global fit related to the octant of $\\theta_{23}$ as well as the CP violating phase $\\delta_\\mathrm{CP}$. The favored values of $\\delta_\\mathrm{CP}$ are around $3\\pi/2$ while values around $\\pi/2$ are disfavored at about $\\Delta\\chi^2 \\simeq 6$. We comment on the non-trivial task to assign a confidence level to this $\\Delta\\chi^2$ value by performing a Monte Carlo study of T2K data.

M. C. Gonzalez-Garcia; Michele Maltoni; Thomas Schwetz

2014-12-16T23:59:59.000Z

423

Neutrino Masses, Lepton Flavor Mixing and Leptogenesis in the Minimal Seesaw Model  

E-Print Network [OSTI]

We present a review of neutrino phenomenology in the minimal seesaw model (MSM), an economical and intriguing extension of the Standard Model with only two heavy right-handed Majorana neutrinos. Given current neutrino oscillation data, the MSM can predict the neutrino mass spectrum and constrain the effective masses of the tritium beta decay and the neutrinoless double-beta decay. We outline five distinct schemes to parameterize the neutrino Yukawa-coupling matrix of the MSM. The lepton flavor mixing and baryogenesis via leptogenesis are investigated in some detail by taking account of possible texture zeros of the Dirac neutrino mass matrix. We derive an upper bound on the CP-violating asymmetry in the decay of the lighter right-handed Majorana neutrino. The effects of the renormalization-group evolution on the neutrino mixing parameters are analyzed, and the correlation between the CP-violating phenomena at low and high energies is highlighted. We show that the observed matter-antimatter asymmetry of the Universe can naturally be interpreted through the resonant leptogenesis mechanism at the TeV scale. The lepton-flavor-violating rare decays, such as $\\mu \\to e + \\gamma$, are also discussed in the supersymmetric extension of the MSM.

Wan-lei Guo; Zhi-zhong Xing; Shun Zhou

2006-12-05T23:59:59.000Z

424

On the ambiguities in the tri-bimaximal mixing matrix and corresponding charged lepton corrections  

E-Print Network [OSTI]

Two negative signs naturally appear in the $U_{\\mu 1}$ and $U_{\\tau 2}$ elements of the Tri-bimaximal (TBM) matrix for positive values of the mixing angles $\\theta_{12}$ and $\\theta_{23}$. Apart from this, in other TBM matrices negative signs are shifted to other elements in each case. They account for positive as well as negative values of $\\theta_{12}$ and $\\theta_{23}$. We discuss the sign ambiguity in the TBM matrix and find that the TBM matrices, in fact, can be divided into two groups under certain circumstances. Interestingly, this classification of TBM matrices is accompanied by two different $\\mu-\\tau$ symmetric mass matrices which can separately be related to the groups. To accommodate non-zero value of $\\theta_{13}$ and deviate $\\theta_{23}$ towards first octant, we then perturb the TBM mixing ansatz with the help of charged lepton correction. The diagonalizing matrices for charged lepton mass matrices also possess sign ambiguity and respect the grouping of TBM matrices. They are parametrized in te...

Duarah, Chandan

2015-01-01T23:59:59.000Z

425

Role of colliding geometry on the balance energy of mass-asymmetric systems  

E-Print Network [OSTI]

We study the role of colliding geometry on the balance energy (Ebal) of mass-asymmetric systems by varying the mass asymmetry ({\\eta} = AT - Ap/AT + AP, where AT and AP are the masses of the target and projectile, respectively) from 0.1 to 0.7, over the mass range 40-240 and on the mass dependence of the balance energy. Our findings reveal that colliding geometry has a significant effect on the Ebal of asymmetric systems. We find that, as we go from central collisions to peripheral ones, the effect of mass asymmetry on Ebal increases throughout the mass range. Interestingly, we find that for every fixed system mass (Atot) the effect of the impact parameter variation is almost uniform throughout the mass-asymmetry range. For each {\\eta}, Ebal follows a power-law behavior (\\propto A{\\tau}) at all colliding geometries

Supriya Goyal

2011-04-16T23:59:59.000Z

426

Recombinant Science: The Birth of the Relativistic Heavy Ion Collider (431st Brookhaven Lecture)  

SciTech Connect (OSTI)

As part of the celebration of Brookhaven Lab's 60th anniversary, Robert P. Crease, the Chair of the Philosophy Department at Stony Brook University and BNL's historian, will present the second of two talks on the Lab's history. In "Recombinant Science: The Birth of the Relativistic Heavy Ion Collider," Dr. Crease will focus on the creation of the world's most powerful colliding accelerator for nuclear physics. Known as RHIC, the collider, as Dr. Crease will recount, was formally proposed in 1984, received initial construction funding from the U.S. Department of Energy in 1991, and started operating in 2000. In 2005, the discovery at RHIC of the world's most perfect liquid, a state of matter that last existed just moments after the Big Bang, was announced, and, since then, this perfect liquid of quarks and gluons has been the subject of intense study.

Crease, Robert P. (Ph.D, Department of Philosophy, Stony Brook University) [Ph.D, Department of Philosophy, Stony Brook University

2007-12-12T23:59:59.000Z

427

Biholomorphic maps with linear parts having Jordan blocks: linearization and  

E-Print Network [OSTI]

Jordan block. Our main result proves convergence of the linearizing transformation of maps for which the Jordan part of the spectrum lies inside the unit circle and the spectrum satis#12;es a R in (C [x]) n , (1.2) where C [x] stands for the set of all formal power series with complex coe

428

Linear operator inequalities for strongly stable weakly regular linear systems  

E-Print Network [OSTI]

that A has compact resolvent and its eigenvectors form a Riesz basis for the state space, we give an explicit to a spectral factorization problem and to a lin- ear quadratic optimal control problem. More concretely R, which implies that R #21; 0. The associated linear matrix inequality in the unknown self

Curtain, Ruth F.

429

Final Report - The Decline and Fall of the Superconducting Super Collider  

SciTech Connect (OSTI)

In October 1993 the US Congress terminated the Superconducting Super Collider — at the time the largest pure-science project ever attempted, with a total cost estimated to exceed $10 billion. It was a stunning loss for the US highenergy physics community, which until that moment had perched for decades at the pinnacle of American science. Ever since 1993, this once-dominant scientific community has been in gradual decline. With the 2010 startup of research on the CERN Large Hadron Collider and the 2011 shutdown of the Fermilab Tevatron, world leadership in elementary-particle physics has crossed the Atlantic and returned to Europe.

RIORDAN, MICHAEL

2011-11-29T23:59:59.000Z

430

GPU-optimized Code for Long-term Simulations of Beam-beam Effects in Colliders  

SciTech Connect (OSTI)

We report on the development of the new code for long-term simulation of beam-beam effects in particle colliders. The underlying physical model relies on a matrix-based arbitrary-order symplectic particle tracking for beam transport and the Bassetti-Erskine approximation for beam-beam interaction. The computations are accelerated through a parallel implementation on a hybrid GPU/CPU platform. With the new code, a previously computationally prohibitive long-term simulations become tractable. We use the new code to model the proposed medium-energy electron-ion collider (MEIC) at Jefferson Lab.

Roblin, Yves [JLAB; Morozov, Vasiliy [JLAB; Terzic, Balsa [JLAB; Aturban, Mohamed A. [Old Dominion University; Ranjan, D. [Old Dominion University; Zubair, Mohammed [Old Dominion University

2013-06-01T23:59:59.000Z

431

Role of colliding geometry on the N/Z dependence of balance energy  

E-Print Network [OSTI]

We study the role of colliding geometry on the N/Z dependence of balance energy using isospin-dependent quantum molecular dynamics model. Our study reveals that the N/Z dependence of balance energy becomes much steeper for peripheral collisions as compared to the central collisions. We also study the effect of system mass on the impact parameter dependence of N/Z dependence of balance energy. The study shows that lighter systems shows greater sensitivity to colliding geometry towards the N/Z dependence.

Sakshi Gautam; Aman D. Sood; Rajeev K. Puri

2011-08-01T23:59:59.000Z

432

Interaction region design for a RHIC-based medium-energy electron-ion collider  

SciTech Connect (OSTI)

As a first step in a staged approach towards a RHIC-based electron-ion collider, installation of a 4 GeV energy-recovery linac (ERL) in one of the RHIC interaction regions is currently under investigation. To minimize costs, the interaction region of this collider has to use the present RHIC magnets for focusing of the high-energy ion beam. Meanwhile, electron low-beta focusing needs to be added in the limited space available between the existing separator dipoles. We discuss the challenges and present the current design status of this e-A interaction region.

Montag,C.; Beebe-Wang, J.

2009-05-04T23:59:59.000Z

433

Les Houches guidebook to Monte Carlo generators for hadron collider physics  

SciTech Connect (OSTI)

Recently the collider physics community has seen significant advances in the formalisms and implementations of event generators. This review is a primer of the methods commonly used for the simulation of high energy physics events at particle colliders. We provide brief descriptions, references, and links to the specific computer codes which implement the methods. The aim is to provide an overview of the available tools, allowing the reader to ascertain which tool is best for a particular application, but also making clear the limitations of each tool.

Dobbs, Matt A.; Frixione, Stefano; Laenen, Eric; Tollefson, Kirsten

2004-03-01T23:59:59.000Z

434

Higgs bosons, electroweak symmetry breaking, and the physics of the Large Hadron Collider  

SciTech Connect (OSTI)

The Large Hadron Collider, a 7 {circle_plus} 7 TeV proton-proton collider under construction at CERN (the European Laboratory for Particle Physics in Geneva), will take experiments squarely into a new energy domain where mysteries of the electroweak interaction will be unveiled. What marks the 1-TeV scale as an important target? Why is understanding how the electroweak symmetry is hidden important to our conception of the world around us? What expectations do we have for the agent that hides the electroweak symmetry? Why do particle physicists anticipate a great harvest of discoveries within reach of the LHC?

Quigg, Chris; /Fermilab /CERN

2007-02-01T23:59:59.000Z

435

Collider Detector at Fermilab (CDF): Data from Supersymmetry, New Phenomena Research of the CDF Exotics Group  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The Exotics group searches for Supersymmetry and other New Phenomena. Their public web page makes data and numerous figures available from both CDF Runs I and II.

436

Collider Detector at Fermilab (CDF): Data from the Top Group's Top Quark Research  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The Top group studies the properties of the top quark, the heaviest known fundamental particle. Their public web page makes data and numerous figures available from both CDF Runs I and II.

437

Electron-Ion Collider - taking us to the next QCD frontier  

E-Print Network [OSTI]

In this talk, I demonstrate that the proposed Electron-Ion Collider (EIC) will be an ideal and unique future facility to address many overarching questions about QCD and strong interaction physics at one place. The EIC will be the world's first polarized electron-proton (and light ion), as well as the first electron-nucleus collider at flexible collision energies. With its high luminosity and beam polarization, the EIC distinguishes itself from HERA and the other fixed target electron-hadron facilities around the world. The EIC is capable of taking us to the next QCD frontier to explore the glue that binds us all.

Jian-Wei Qiu

2014-12-08T23:59:59.000Z

438

Les Houches Guidebook to Monte Carlo generators for hadron collider physics  

SciTech Connect (OSTI)

Recently the collider physics community has seen significant advances in the formalisms and implementations of event generators. This review is a primer of the methods commonly used for the simulation of high energy physics events at particle colliders. We provide brief descriptions, references, and links to the specific computer codes which implement the methods. The aim is to provide an overview of the available tools, allowing the reader to ascertain which tool is best for a particular application, but also making clear the limitations of each tool.

Dobbs, M.A

2004-08-24T23:59:59.000Z

439

Search for Supersymmetry Using Weak Boson Fusion Processes in Proton-Proton Collisions at the Large Hadron Collider  

E-Print Network [OSTI]

In 2012, the Large Hadron Collider at CERN (LHC) collided protons at an unprecedented center-of-mass energy of 8 TeV. With data corresponding to a total integrated luminosity of 19.7 fb^(?1), the Compact Muon Solenoid (CMS) collaboration is studying...

Flanagan, Will

2014-08-08T23:59:59.000Z

440

Linearized theory of peridynamic states.  

SciTech Connect (OSTI)

A state-based peridynamic material model describes internal forces acting on a point in terms of the collective deformation of all the material within a neighborhood of the point. In this paper, the response of a state-based peridynamic material is investigated for a small deformation superposed on a large deformation. The appropriate notion of a small deformation restricts the relative displacement between points, but it does not involve the deformation gradient (which would be undefined on a crack). The material properties that govern the linearized material response are expressed in terms of a new quantity called the modulus state. This determines the force in each bond resulting from an incremental deformation of itself or of other bonds. Conditions are derived for a linearized material model to be elastic, objective, and to satisfy balance of angular momentum. If the material is elastic, then the modulus state is obtainable from the second Frechet derivative of the strain energy density function. The equation of equilibrium with a linearized material model is a linear Fredholm integral equation of the second kind. An analogue of Poincare's theorem is proved that applies to the infinite dimensional space of all peridynamic vector states, providing a condition similar to irrotationality in vector calculus.

Silling, Stewart Andrew

2009-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Linear electric field mass spectrometry  

DOE Patents [OSTI]

A mass spectrometer and methods for mass spectrometry are described. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field. 8 figs.

McComas, D.J.; Nordholt, J.E.

1992-12-01T23:59:59.000Z

442

Transformations for densities Linear transformations  

E-Print Network [OSTI]

' & $ % Lecture 28 Transformations for densities Linear transformations 1-1 differentiable functions General transformations Expectation of a function 1 #12;' & $ % Transformations for discrete transformation of a U[0, 1] · Take X U[0, 1], so that fX(x) = 1 0 0 and set Y

Adler, Robert J.

443

Search for Top Squarks in R-Parity-Violating Supersymmetry Using Three or More Leptons and b-Tagged Jets  

E-Print Network [OSTI]

A search for anomalous production of events with three or more isolated leptons and bottom-quark jets produced in pp collisions at ?s = 8??TeV is presented. The analysis is based on a data sample corresponding to an ...

Apyan, Aram

444

Inclusive lepton production in hadronic events from e/sup +/e/sup -/ annihilation at 29 GeV  

SciTech Connect (OSTI)

We have measured the production rates of prompt electrons and muons in hadronic events from e/sup +/e/sup -/ annihilation at 29 GeV. The inclusive rate per hadronic event for leptons with total momenta greater than 2 GeV/c is determined to be (0.033 +- 0.003 +- 0.012) for electrons and (0.037 +- 0.005 +- 0.008) for muons. We measure the longitudinal and transverse momentum spectra of these leptons. The harder transverse momentum spectrum of leptons from bottom and charm quark relative to charm decays allows us to separate the bottom and charm quark contributions to the prompt lepton signal. The longitudinal momentum distributions allow us to study the fragmentation properties of these heavy quarks. For charm quarks we find average semileptonic branching ratios of (6.4 +- 1.3 +- 2.8)% into electrons and (8.1 +- 1.6 +- 1.8)% into muons. For bottom quarks we find average branching ratios of (12.9 +- 2.5 +- 2.0)% into electrons and (12.2 +- 5.0 +- 3.0)% into muons. The fragmentation function for bottom quarks is determined to be peaked at large z with /sub b/ approx. = 0.75. 46 references.

Nelson, M.E.

1983-10-01T23:59:59.000Z

445

CDF note 10582 Search for SM Higgs boson production in association with tt using no lepton final state  

E-Print Network [OSTI]

CDF note 10582 Search for SM Higgs boson production in association with t¯t using no lepton final is that t¯t decay all hadronic mode (all t decay into bqq ). In both cases we consider that the Higgs boson discriminant variable from different neural network to discriminate the Higgs boson signal from remained

Fermilab

446

Evidence for Higgs boson decays to tau leptons with the ATLAS detector and prospects for future measurements  

E-Print Network [OSTI]

Recent results on the search for Higgs boson decays to tau leptons with the ATLAS detector are presented based on approximately 25 $\\text{fb}^{-1}$ of proton-proton collision data collected at $\\sqrt{s}=$ 7 and 8 TeV. Prospects of future measurements with proposed ATLAS upgrades at the High Luminosity LHC are also presented.

Tuna, Alexander Naip; The ATLAS collaboration

2015-01-01T23:59:59.000Z

447

arXiv:heplat/0610083v1 Hadron and Lepton School and Conference, Tehran, Iran, May 19th 2006 1  

E-Print Network [OSTI]

arXiv:hep­lat/0610083v1 13 Oct 2006 Hadron and Lepton School and Conference, Tehran, Iran, May 19th, Iran, May 19th 2006 L (a) (b) L # Figure 1: Two potentially relevant graphs to the h#22;qqi

Lunds Universitet,

448

Why quantum dynamics is linear  

E-Print Network [OSTI]

Quantum dynamics is linear. How do we know? From theory or experiment? The history of this question is reviewed. Nonlinear generalizations of quantum mechanics have been proposed. They predict small but clear nonlinear effects, which very accurate experiments have not seen. Is there a reason in principle why nonlinearity is not found? Is it impossible? Does quantum dynamics have to be linear? Attempts to prove this have not been decisive, because either their assumptions are not compelling or their arguments are not conclusive. The question has been left unsettled. There is a simple answer, based on a simple assumption. It was found in two steps separated by 44 years. They are steps back to simpler and more compelling assumptions. A proof of the assumptions of the Wigner-Bargmann proof has been known since 1962. It assumes that the maps of density matrices in time are linear. For this step, it is also assumed that density matrices are mapped one-to-one onto density matrices. An alternative is to assume that pure states are mapped one-to-one onto pure states and that entropy does not decrease. In a step taken in 2006, it is proved that the maps of density matrices in time are linear. It is assumed, as in the earlier step, that at each time the physical quantities and states are described by the usual linear structures of quantum mechanics, so the question is only about how things change in time. Beyond that, the proof assumes only that the dynamics does not depend on anything outside the system, but must allow the system to be described as part of a larger system.

Thomas F. Jordan

2007-02-16T23:59:59.000Z

449

Linear Optics From Closed Orbits (LOCO): An Introduction  

SciTech Connect (OSTI)

The LOCO code is used to find and correct errors in the linear optics of storage rings. The original FORTRAN code was written to correct the optics of the NSLS X-Ray ring, and was applied soon thereafter to debug problems with the ALS optics. The ideas used in the code were developed from previous work at SLAC. Several years ago, LOCO was rewritten in MATLAB. As described in this newsletter, the MATLAB version includes a user-friendly interface, with many useful fitting and analysis options. LOCO has been used at many accelerators. Presently, a search for LOCO in the text of papers on the Joint Accelerator Conferences Website yields 107 papers. A comprehensive survey of applications will not be included here. Details of recent results at a few light sources are included in this newsletter. In the past, the quality of LOCO fitting results varied significantly, depending on the storage ring. In particular, the results were mixed for colliding beam facilities, where there tend to be fewer BPMs that in light sources. Fitting rings with less BPM data to constrain the fit optics parameters often led to unreasonably large fit quadrupole gradient variations. Recently, modifications have been made to the LOCO fitting algorithm which leads to much better results when the BPM data does not tightly constrain the fit parameters. The modifications are described in this newsletter, and an example of results with this new algorithm is included.

Safranek, James; /SLAC

2009-06-18T23:59:59.000Z

450

Measurement of the top quark mass in the lepton+jets channel using the ideogram method  

E-Print Network [OSTI]

in the overall likelihood fit. This paper is organized as follows: Sections II and III describe the D0 Run II detector and the event reconstruc- tion, respectively. Sections IV, V, and VI describe the data and simulation samples used and outline the event selec... in Sec. IX and the systematic uncertainties are discussed in Sec. X. Section XI presents a cross-check of the JES calibration, followed by the con- clusion in Sec. XII. II. THE D0 DETECTOR Run II of the Fermilab Tevatron collider started in 2001 after...

Baringer, Philip S.; Bean, Alice; Hensel, Carsten; Moulik, Tania; Wilson, Graham Wallace; Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.

2007-05-11T23:59:59.000Z

451

Emission characteristics and dynamics of the stagnation layer in colliding laser produced plasmas  

E-Print Network [OSTI]

Emission characteristics and dynamics of the stagnation layer in colliding laser produced plasmas P been investigated using time and space resolved optical emission spectroscopies and spectrally and angularly resolved fast imaging. The emission results highlight a difference in neutral atom and ion

Harilal, S. S.

452

Summary audit report on lessons learned from the Superconducting Super Collider Project  

SciTech Connect (OSTI)

In October 1993, the Congress decided to terminate the Superconducting Super Collider (SSC) project after expending about $1.57 billion on the project. While both internal and external factors contributed to the demise of the project, its cancellation offers the Department a unique opportunity to analyze what went wrong, correct the mistakes, and apply the lessons learned to future large-scale projects.

NONE

1996-04-23T23:59:59.000Z

453

Two fungal symbioses collide: endophytic fungi are not welcome in leaf-cutting ant gardens  

E-Print Network [OSTI]

Two fungal symbioses collide: endophytic fungi are not welcome in leaf-cutting ant gardens Sunshine, while the leaf material they provide to their garden is usually filled with endophytic fungi. The ants and their cultivar may interact with hundreds of endophytic fungal species, yet little is known about

Bermingham, Eldredge

454

Two fungal symbioses collide: endophytic fungi are not welcome in leaf-cutting ant gardens  

E-Print Network [OSTI]

Two fungal symbioses collide: endophytic fungi are not welcome in leaf-cutting ant gardens Sunshine with their fungal garden, while the leaf material they provide to their garden is usually filled with endophytic fungi. The ants and their cultivar may interact with hundreds of endophytic fungal species, yet little

Bermingham, Eldredge

455

A NEW GENERATION OF EBIS: HIGH CURRENT DEVICES FOR ACCELERATORS AND COLLIDERS*  

E-Print Network [OSTI]

A NEW GENERATION OF EBIS: HIGH CURRENT DEVICES FOR ACCELERATORS AND COLLIDERS* E. Beebe, J. Alessi of magnitude compared to fixed target operation of existing accelerators.[1] RHIC, for example, requires 3.4x10 20 times higher than electron beams utilized in devices at accelerators at Dubna, Saclay

456

Les Houches 2013: Physics at TeV Colliders: Standard Model Working Group Report  

E-Print Network [OSTI]

This Report summarizes the proceedings of the 2013 Les Houches workshop on Physics at TeV Colliders. Session 1 dealt primarily with (1) the techniques for calculating standard model multi-leg NLO and NNLO QCD and NLO EW cross sections and (2) the comparison of those cross sections with LHC data from Run 1, and projections for future measurements in Run 2.

J. Butterworth; G. Dissertori; S. Dittmaier; D. de Florian; N. Glover; K. Hamilton; J. Huston; M. Kado; A. Korytov; F. Krauss; G. Soyez; J. R. Andersen; S. Badger; L. Barzè; J. Bellm; F. U. Bernlochner; A. Buckley; J. Butterworth; N. Chanon; M. Chiesa; A. Cooper-Sarkar; L. Cieri; G. Cullen; H. van Deurzen; G. Dissertori; S. Dittmaier; D. de Florian; S. Forte; R. Frederix; B. Fuks; J. Gao; M. V. Garzelli; T. Gehrmann; E. Gerwick; S. Gieseke; D. Gillberg; E. W. N. Glover; N. Greiner; K. Hamilton; T. Hapola; H. B. Hartanto; G. Heinrich; A. Huss; J. Huston; B. Jäger; M. Kado; A. Kardos; U. Klein; F. Krauss; A. Kruse; L. Lönnblad; G. Luisoni; Daniel Maître; P. Mastrolia; O. Mattelaer; J. Mazzitelli; E. Mirabella; P. Monni; G. Montagna; M. Moretti; P. Nadolsky; P. Nason; O. Nicrosini; C. Oleari; G. Ossola; S. Padhi; T. Peraro; F. Piccinini; S. Plätzer; S. Prestel; J. Pumplin; K. Rabbertz; Voica Radescu; L. Reina; C. Reuschle; J. Rojo; M. Schönherr; J. M. Smillie; J. F. von Soden-Fraunhofen; G. Soyez; R. Thorne; F. Tramontano; Z. Trocsanyi; D. Wackeroth; J. Winter; C-P. Yuan; V. Yundin; K. Zapp

2014-05-05T23:59:59.000Z

457

The $B-L$ Supersymmetric Standard Model with Inverse Seesaw at the Large Hadron Collider  

E-Print Network [OSTI]

We review the TeV scale $B-L$ extension of the Minimal Supersymmetric Standard Model (BLSSM) where an inverse seesaw mechanism of light neutrino mass generation is naturally implemented and concentrate on its hallmark manifestations at the Large Hadron Collider (LHC).

Khalil, S

2015-01-01T23:59:59.000Z

458

Physics Opportunities at a Muon Collider Kirk T. McDonald  

E-Print Network [OSTI]

@puphep.princeton.edu January 7, 1999 DPF'99 Session 11B: Future Accelerator Projects Muon Collider main page: http at any energy. · Intense neutrino beams and spallation neutron beams are available as byproducts. Muons. ­ A rich supersymmetric sector. ­ ... And more .... · That our investment in future accelerators

McDonald, Kirk

459

T864 (MiniMax): A Search for Disoriented Chiral Condensate at the Fermilab Collider  

E-Print Network [OSTI]

A small test/experiment has been performed at the Fermilab Collider to measure charged particle and photon multiplicities in the forward direction, $\\eta \\approx 4.1$. The primary goal is to search for disoriented chiral condensate (DCC). The experiment and analysis methods are described, and preliminary results of the DCC search are presented.

J. D. Bjorken

1996-10-16T23:59:59.000Z

460

Physics and Analysis at a Hadron Collider - Searching for New Physics (2/3)  

ScienceCinema (OSTI)

This is the second lecture of three which together discuss the physics of hadron colliders with an emphasis on experimental techniques used for data analysis. This second lecture discusses techniques important for analyses searching for new physics using the CDF B_s --> mu+ mu- search as a specific example. The lectures are aimed at graduate students.

None

2011-10-06T23:59:59.000Z

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Study of nuclear dynamics of neutron-rich colliding pair at energy of vanishing flow  

E-Print Network [OSTI]

We study nuclear dynamics at the energy of vanishing flow of neutron-rich systems having N/Z ratio 1.0, 1.6 and 2.0 throughout the mass range at semi central colliding geometry. In particular we study the behavior of average and maximum density with N/Z dependence of the system.

Sakshi Gautam

2011-07-28T23:59:59.000Z

462

Structure and Dynamics of Colliding Plasma Jets C. K. Li,1,* D. D. Ryutov,2  

E-Print Network [OSTI]

Structure and Dynamics of Colliding Plasma Jets C. K. Li,1,* D. D. Ryutov,2 S. X. Hu,3 M. J at various angles shed light on the structures and dynamics of these collisions. The observations compare noncollinear jets, the observed flow structure is similar to the analytic model's prediction of a character

463

Measurement of proton and anti-proton intensities in the Tevatron Collider  

SciTech Connect (OSTI)

This paper describes the techniques used to measure the intensities of the proton (p) and anti-proton ({bar p}) beams in the Tevatron collider. The systems provide simultaneous measurements of the intensity of the 36 proton and 36 antiproton bunches and their longitudinal profiles.

Stephen Pordes et al.

2003-06-04T23:59:59.000Z

464

Operational plasma density and laser parameters for future colliders based on laser-plasma accelerators  

SciTech Connect (OSTI)

The operational plasma density and laser parameters for future colliders based on laser-plasma accelerators are discussed. Beamstrahlung limits the charge per bunch at low plasma densities. Reduced laser intensity is examined to improve accelerator efficiency in the beamstrahlung-limited regime.

Schroeder, C. B.; Esarey, E.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2012-12-21T23:59:59.000Z

465

Colliding and Moving Bose-Einstein Condensates: Studies of superfluidity and optical tweezers for condensate transport  

E-Print Network [OSTI]

Colliding and Moving Bose-Einstein Condensates: Studies of superfluidity and optical tweezers for condensate transport by Ananth P. Chikkatur Submitted to the Department of Physics in partial fulfillment Bose-Einstein Condensates: Studies of superfluidity and optical tweezers for condensate transport

466

DESIGN OF THE MERCURY HANDLING SYSTEM FOR A MUON COLLIDER/NEUTRINO FACTORY TARGET  

E-Print Network [OSTI]

DESIGN OF THE MERCURY HANDLING SYSTEM FOR A MUON COLLIDER/NEUTRINO FACTORY TARGET V.B. Graves , Oak is a free mercury jet within a 20-T magnetic field being impacted by an 8-GeV proton beam. A pool of mercury serves as a receiving reservoir for the mercury and a dump for the unexpended proton beam. Modifications

McDonald, Kirk

467

The Neutrino Factory and Muon Collider Collaboration From a Neutrino Factory to Carlsbad  

E-Print Network [OSTI]

The Neutrino Factory and Muon Collider Collaboration From a Neutrino Factory to Carlsbad BNL FNAL KEK CERN Carlsbad Kirk T. McDonald Princeton U. mcdonald@puphep.princeton.edu Workshop on the Next Generation U.S. Underground Science Facility Carlsbad, NM, June 13, 2000 http://puhep1.princeton

McDonald, Kirk

468

The Neutrino Factory and Muon Collider Collaboration The R&D Program for  

E-Print Network [OSTI]

Channels Beam Aluminum Plate HASSANEIN (ANL) NEUTRINO-FACTORY TARGET DESIGN Cylindrical Graphite Target Time MaximumTotalPressure,katm Deposition time, µs Carbon P T R = 7 mm Q av = 20 J/g Cylindrical Target Collider Collaboration Simple Target Tests Simple targets: Pipe, trough, waterfall: Plus: carbon and nickel

McDonald, Kirk

469

Events with Isolated Leptons and Missing Transverse Momentum in ep Collisions at HERA  

E-Print Network [OSTI]

The analysis of events with isolated leptons and missing transverse momentum in the H1 experiment is discussed for the electron, muon and tau channels. In the Standard Model (SM) framework, production of real W-bosons gives rise to such topologies. Contributions to the background are dominated by QCD processes. An excess of observed signal over background presents a chance of the discovery of new physics. The results using the HERA 1994-2006 data set corresponding to 341 pb^-1 are presented. While the e- p sample shows good agreement between data and SM expectation, in e+ p collisions an excess over the SM expectation with 3.4 sigma significance is observed at high hadronic transverse momentum.

G. Brandt

2007-01-28T23:59:59.000Z

470

Chiral sum rules and vacuum condensates from tau-lepton decay data  

E-Print Network [OSTI]

QCD finite energy sum rules, together with the latest updated ALEPH data on hadronic decays of the tau-lepton are used in order to determine the vacuum condensates of dimension $d=2$ and $d=4$. These data are also used to check the validity of the Weinberg sum rules, and to determine the chiral condensates of dimension $d=6$ and $d=8$, as well as the chiral correlator at zero momentum, proportional to the counter term of the ${\\cal{O}}(p^4)$ Lagrangian of chiral perturbation theory, $\\bar{L}_{10}$. Suitable (pinched) integration kernels are introduced in the sum rules in order to suppress potential quark-hadron duality violations. We find no compelling indications of duality violations in the kinematic region above $s \\simeq 2.2$ GeV$^2$ after using pinched integration kernels.

C. A. Dominguez; L. A. Hernandez; K. Schilcher; H. Spiesberger

2015-02-16T23:59:59.000Z

471

Search for Supersymmetry with Tau Leptons in Data from the ATLAS Experiment at the LHC  

E-Print Network [OSTI]

This thesis presents the search for Supersymmetry in events with high pT jets, a large amount of missing transverse energy and at least one hadronically decaying ? lepton in data from the ATLAS detector. Two analyses are presented in detail: one performed on the data collected during the year 2010 and one on the full data set recorded by ATLAS in year 2012. The latter analysis is based on two published papers in which the author of this thesis has been involved. These are Paper I and Paper II attached to this thesis. Paper II is an ATLAS conference note. The final version of the analysis is in an advanced stage of preparation with scheduled submission for publication in early Summer 2014.

Sjursen, Therese Berge; Osland, Per

2014-06-26T23:59:59.000Z

472

Electroweak corrections to lepton pair production in association with two hard jets at the LHC  

E-Print Network [OSTI]

We compute the next-to-leading order corrections of $O(\\alpha_s^2\\alpha^3)$ to the hadronic production of two oppositely charged leptons and two hard jets, $p p \\to j j l^- l^+$, using Recola and Collier. We include electroweak and QCD corrections at the given order and all off-shell effects. We provide detailed predictions for the LHC operating at 13 TeV and obtain per-cent-level corrections for the total cross section. For differential distributions we find significant non-uniform distortions in high-energy tails at the level of several ten per cent due to electroweak Sudakov logarithms and deformations at the level of a few per cent for angular variables.

Ansgar Denner; Lars Hofer; Andreas Scharf; Sandro Uccirati

2014-11-04T23:59:59.000Z

473

LCPHSM2004005 Study of Higgs Boson Pair Production at  

E-Print Network [OSTI]

LC­PHSM­2004­005 March 2004 Study of Higgs Boson Pair Production at Linear Collider K. Desch a , TV for the measurement of the neutral Higgs boson properties within the framework of the MSSM. The process of associated Higgs boson production with subsequent decays of Higgs bosons into b­quark and #­lepton pairs

474

Segmented rail linear induction motor  

DOE Patents [OSTI]

A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces.

Cowan, Jr., Maynard (1107 Stagecoach Rd. SE., Albuquerque, NM 87123); Marder, Barry M. (1412 Pinnacle View Dr. NE., Albuquerque, NM 87123)

1996-01-01T23:59:59.000Z

475

Segmented rail linear induction motor  

DOE Patents [OSTI]

A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces. 6 figs.

Cowan, M. Jr.; Marder, B.M.

1996-09-03T23:59:59.000Z

476

Cast dielectric composite linear accelerator  

DOE Patents [OSTI]

A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

Sanders, David M. (Livermore, CA); Sampayan, Stephen (Manteca, CA); Slenes, Kirk (Albuquerque, NM); Stoller, H. M. (Albuquerque, NM)

2009-11-10T23:59:59.000Z

477

Precision linear ramp function generator  

DOE Patents [OSTI]

A ramp function generator is provided which produces a precise linear ramp function which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.

Jatko, W.B.; McNeilly, D.R.; Thacker, L.H.

1984-08-01T23:59:59.000Z

478

Search for Supersymmetry in Events with Three Leptons and Missing Transverse Momentum in ?s=7??TeV pp Collisions with the ATLAS Detector  

E-Print Network [OSTI]

A search for the weak production of charginos and neutralinos decaying to a final state with three leptons (electrons or muons) and missing transverse momentum is presented. The analysis uses 2.06??fb[superscript -1] of ...

Taylor, Frank E.

479

Search for the Lepton-Flavor-Violating Decays B[0 over s] ? e[superscript ±]?[superscript ?] and B[superscript 0] ? e[superscript ±]?[superscript ?  

E-Print Network [OSTI]

A search for the lepton-flavor-violating decays B[0 over s] ? e[superscript ±]?[superscript ?] and B[superscript 0] ? e[superscript ±]?[superscript ?] is performed with a data sample, corresponding to an integrated luminosity ...

Williams, Michael

480

Measurement of the t[bar over t] production cross section in pp collisions at ?s = 8 TeV in dilepton final states containing one ? lepton  

E-Print Network [OSTI]

The top-quark pair production cross section is measured in final states with one electron or muon and one hadronically decaying ? lepton from the process t[bar over t] ? (??[subscript ?])(??[subscript ?])b[bar over b], ...

Zhukova, Victoria

Note: This page contains sample records for the topic "linear colliders lepton" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Measurement of Angular Correlations in Drell–Yan Lepton Pairs to Probe Z/?[superscript ?] Boson Transverse Momentum at ?s = 7 TeV with the ATLAS Detector  

E-Print Network [OSTI]

A measurement of angular correlations in Drell–Yan lepton pairs via the ?[* over ?] observable is presented. This variable probes the same physics as the Z/?[superscript ?] boson transverse momentum with a better experimental ...

Taylor, Frank E.