National Library of Energy BETA

Sample records for lepton types electron

  1. Search for type-III seesaw heavy leptons in pp collisions at s=8 TeVwith the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2015-08-03

    A search for the pair production of heavy leptons (N?,L±) predicted by the type-III seesaw theory formulated to explain the origin of small neutrino masses is presented. The decay channels N??W±l? (?=e,?,?) and L±?W±? (?=?e,??,??) are considered. The analysis is performed using the final state that contains two leptons (electrons or muons), two jets from a hadronically decaying W boson and large missing transverse momentum. The data used in the measurement correspond to an integrated luminosity of 20.3 fb?¹ of pp collisions at s?=8 TeV collected by the ATLAS detector at the LHC. No evidence of heavy lepton pair productionmore »is observed. Heavy leptons with masses below 325–540 GeV are excluded at the 95% confidence level, depending on the theoretical scenario considered.« less

  2. Search for type-III seesaw heavy leptons inppcollisions ats=8 TeVwith the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O.?S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2015-08-01

    A search for the pair production of heavy leptons (N?,L±) predicted by the type-III seesaw theory formulated to explain the origin of small neutrino masses is presented. The decay channels N??W±l? (?=e,?,?) and L±?W±? (?=?e,??,??) are considered. The analysis is performed using the final state that contains two leptons (electrons or muons), two jets from a hadronically decaying W boson and large missing transverse momentum. The data used in the measurement correspond to an integrated luminosity of 20.3??fb?¹ of pp collisions at s?=8??TeV collected by the ATLAS detector at the LHC. No evidence of heavy lepton pair production is observed.more »Heavy leptons with masses below 325–540 GeV are excluded at the 95% confidence level, depending on the theoretical scenario considered.« less

  3. 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

  4. Searching for Lepton Flavor Violation at a Future High Energy Electron-Positron Collider

    E-Print Network [OSTI]

    Brandon Murakami; Tim M. P. Tait

    2014-10-06

    We consider theories where lepton flavor is violated, in particular concentrating on the four fermion operator consisting of three electrons and a tau. Strong constraints are available from existing searches for tau -> eee, requiring the scale of the contact interaction to be less than ~(9 TeV)^-2. We reexamine this type of physics, assuming that the particles responsible are heavy (with masses greater than ~TeV) such that a contact interaction description continues to be applicable at the energies for a future e+e- collider. We find that the process e+e- -> e tau can be a very sensitive probe of this kind of physics (even for very conservative assumptions about the detector performance), already improving upon the tau decay bounds to less than ~(11 TeV)^-2 at collider energy sqrt(s) 500 GeV, or reaching beyond ~(35 TeV)^-2 for sqrt(s) = 3 TeV. Even stronger bounds are possible at e-e- colliders in the same energy range.

  5. QCD Corrections to Pair Production of Type III Seesaw Leptons at Hadron Colliders

    E-Print Network [OSTI]

    Richard Ruiz

    2015-09-17

    If kinematically accessible, hadron collider experiments provide an ideal laboratory for the direct production of heavy lepton partners in Seesaw models. In the context of the Type III Seesaw Mechanism, the $\\mathcal{O}(\\alpha_s)$ rate and shape corrections are presented for the pair production of hypothetical, heavy $SU(2)_L$ triplet leptons in $pp$ collisions at $\\sqrt{s}=13,$ 14, and 100 TeV. The next-to-leading order (NLO) $K$-factors span, approximately, $K^{NLO}=1.1 - 1.4$ for both charged current and neutral current processes over a triplet mass range $m_T = 100~\\text{GeV}-2\\text{TeV}$. Total production cross sections exhibit a $^{+5\\%}_{-6\\%}$ scale dependence at 14 TeV and $\\pm1\\%$ at 100 TeV. The NLO differential $K$-factors for heavy lepton kinematics are largely flat, suggesting that na\\"ive scaling by the total $K^{NLO}$ is reasonably justified. The resummed transverse momentum distribution of the dilepton system is presented at leading logarithmic (LL) accuracy. The effects of resummation are large in TeV-scale dilepton systems. Discovery potential to heavy lepton pairs at 14 and 100 TeV is briefly explored: At the High-Luminosity LHC, we estimate a $4.8-6.3\\sigma$ discovery potential maximally for $m_T = 1.5-1.6~\\text{TeV}$ after 3000 fb$^{-1}$. With 300 (3000) fb$^{-1}$, there is $2\\sigma$ sensitivity up to $m_T = 1.3-1.4~\\text{TeV}~(1.7-1.8~\\text{TeV})$ in the individual channels. At 100 TeV and with 10 fb$^{-1}$, a $5\\sigma$ discovery can be achieved for $m_T=1.4-1.6~\\text{TeV}$.

  6. The first measurement of $B$ meson semi-leptonic decay contribution to non-photonic electrons at RHIC

    E-Print Network [OSTI]

    Xiaoyan Lin

    2007-01-30

    We present the first measurement for the $B$ meson semi-leptonic decay contribution to non-photonic electrons at RHIC using non-photonic electron azimuthal correlations with charged hadrons in p+p collisions at $\\sqrt{s_{NN}} = 200$ GeV from STAR.

  7. Search for heavy lepton partners of neutrinos in proton–proton collisions in the context of the type III seesaw mechanism

    E-Print Network [OSTI]

    Apyan, Aram

    A search is presented in proton–proton collisions at ?s = 7 TeV for fermionic triplet states expected in type III seesaw models. The search is performed using final states with three isolated charged leptons and an imbalance ...

  8. PIC simulation study of the interaction between a relativistically moving leptonic micro-cloud and ambient electrons

    E-Print Network [OSTI]

    Dieckmann, M E; Markoff, S; Borghesi, M; Zepf, M

    2015-01-01

    The jets of compact accreting objects are composed of electrons and a mixture of positrons and ions. These outflows impinge on the interstellar or intergalactic medium and both plasmas interact via collisionless processes. Filamentation (beam-Weibel) instabilities give rise to the growth of strong electromagnetic fields. These fields thermalize the interpenetrating plasmas. Hitherto, the effects imposed by a spatial non-uniformity on filamentation instabilities have remained unexplored. We examine the interaction between spatially uniform background electrons and a minuscule cloud of electrons and positrons. A square micro-cloud of equally dense electrons and positrons impinges in our particle-in-cell (PIC) simulation on a spatially uniform plasma at rest. The mean speed of the micro-cloud corresponds to a relativistic factor of 15, which is relevant for laboratory experiments and for relativistic astrophysical outflows. The spatial distributions of the leptons and of the electromagnetic fields are examined a...

  9. 1 Industrial Electron Accelerators type ILU for Industrial Technologies

    E-Print Network [OSTI]

    1 Industrial Electron Accelerators type ILU for Industrial Technologies The present work describes industrial electron accelerators of the ILU family. Their main parameters, design, principle of action the pulse linear accelerators type ILU are developed and supplied to the industry. The ILU machines

  10. Flexible Electronics New Devices on Nearly Any Type of Substrate

    E-Print Network [OSTI]

    Rogers, John A.

    Flexible Electronics ­ New Devices on Nearly Any Type of Substrate by Angelika Boeer published: 2011-07-06 Flexible electronic devices ­ this is a fascinating topic and becoming more and more such as display systems, flexible and stretchable electronics, or other, no-waver-based devices. Sign up

  11. The SUSY seesaw model and lepton-flavor violation at a future electron-positron linear collider

    E-Print Network [OSTI]

    F. Deppisch; H. Päs; A. Redelbach; R. Rückl; Y. Shimizu

    2004-05-11

    We study lepton-flavor violating slepton production and decay at a future e^+e^- linear collider in context with the seesaw mechanism in mSUGRA post-LEP benchmark scenarios. The present knowledge in the neutrino sector as well as improved future measurements are taken into account. We calculate the signal cross-sections \\sigma(e^{+/-}e^- -> l_{\\beta}^{+/-} l_{\\alpha}^- \\tilde{\\chi}_b^0 \\tilde{\\chi}_a^0); l_{\\delta}=e, \\mu, \\tau; \\alpha =|= \\beta and estimate the main background processes. Furthermore, we investigate the correlations of these signals with the corresponding lepton-flavor violating rare decays l_{\\alpha} -> l_{\\beta} \\gamma. It is shown that these correlations are relatively weakly affected by uncertainties in the neutrino data, but very sensitive to the model parameters. Hence, they are particularly suited for probing the origin of lepton-flavor violation.

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

    E-Print Network [OSTI]

    Gomez-Ceballos, Guillelmo

    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 ...

  13. Universality of Quark-Lepton Mass Matrix

    E-Print Network [OSTI]

    Takeshi Fukuyama; Hiroyuki Nishiura

    2013-01-22

    The recently observed lepton mixing angle $\\theta_{13}$ of the MNS mixing matrix is well incorporated in a universal mixing hypothesis between quark and lepton sectors. This hypothesis asserts that, in the charged lepton diagonal base, all other mass matrices for up- and down-type quarks and light neutrinos are diagonalized by the same unitary matrix except for the phase elements. It is expressed as $V_{CKM}= U_{MNS}(\\delta^\\prime)^\\dagger P U_{MNS}(\\delta)$ for quark mixing matrix $V_{CKM}$ and lepton mixing matrix $U_{MNS}(\\delta)$ in the phenomenological level. Here $P$ is a diagonal phase mass matrix. $\\delta^\\prime$ is a slightly different phase parameter from the Dirac CP violating phase $\\delta=1.1\\pi$ (best fit) in the MNS lepton mixing matrix.

  14. Search for heavy lepton resonances decaying to a Z boson and a lepton in pp collisions at \\( \\sqrt{s}=8 \\) TeV with the ATLAS detector

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

    Aad, G.

    2015-09-16

    In this study, a search for heavy leptons decaying to a Z boson and an electron or a muon is presented. The search is based on pp collision data taken at \\( \\sqrt{s}=8 \\) TeV by the ATLAS experiment at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb?¹. Three high-transverse-momentum electrons or muons are selected, with two of them required to be consistent with originating from a Z boson decay. No significant excess above Standard Model background predictions is observed, and 95% confidence level limits on the production cross section of high-mass trilepton resonances aremore »derived. The results are interpreted in the context of vector-like lepton and type-III seesaw models. For the vector-like lepton model, most heavy lepton mass values in the range 114–176 GeV are excluded. For the type-III seesaw model, most mass values in the range 100–468 GeV are excluded.« less

  15. Lepton-flavored dark matter

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

    Kile, Jennifer; Kobach, Andrew; Soni, Amarjit

    2015-05-01

    In this work, we address two paradoxes. The first is that the measured dark-matter relic density can be satisfied with new physics at O(100 GeV–1 TeV), while the null results from direct-detection experiments place lower bounds of O(10 TeV) on a new-physics scale. The second puzzle is that the severe suppression of lepton-flavor-violating processes involving electrons, e.g. ? ? 3e, ? ? e??, etc., implies that generic new-physics contributions to lepton interactions cannot exist below O(10–100 TeV), whereas the 3.6? deviation of the muon g – 2 from the standard model can be explained by a new physics scale more »TeV). Here, we suggest that it may not be a coincidence that both the muon g – 2 and the relic density can be satisfied by a new-physics scale ?1 TeV. We consider the possibility of a gauged lepton-flavor interaction that couples at tree level only to ?- and ?-flavored leptons and the dark sector. Dark matter thus interacts appreciably only with particles of ? and ? flavor at tree level and has loop-suppressed couplings to quarks and electrons. Remarkably, if such a gauged flavor interaction exists at a scale O(100 GeV–1 TeV), it allows for a consistent phenomenological framework, compatible with the muon g – 2, the relic density, direct detection, indirect detection, charged-lepton decays, neutrino trident production, and results from hadron and e?e? colliders. We suggest experimental tests for these ideas at colliders and for low-energy observables. (author)« less

  16. Lepton-flavored dark matter

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

    Kile, Jennifer; Kobach, Andrew; Soni, Amarjit

    2015-05-01

    In this work, we address two paradoxes. The first is that the measured dark-matter relic density can be satisfied with new physics at O(100 GeV–1 TeV), while the null results from direct-detection experiments place lower bounds of O(10 TeV) on a new-physics scale. The second puzzle is that the severe suppression of lepton-flavor-violating processes involving electrons, e.g. ? ? 3e, ? ? e??, etc., implies that generic new-physics contributions to lepton interactions cannot exist below O(10–100 TeV), whereas the 3.6? deviation of the muon g – 2 from the standard model can be explained by a new physics scale lepton-flavor interaction that couples at tree level only to ?- and ?-flavored leptons and the dark sector. Dark matter thus interacts appreciably only with particles of ? and ? flavor at tree level and has loop-suppressed couplings to quarks and electrons. Remarkably, if such a gauged flavor interaction exists at a scale O(100 GeV–1 TeV), it allows for a consistent phenomenological framework, compatible with the muon g – 2, the relic density, direct detection, indirect detection, charged-lepton decays, neutrino trident production, and results from hadron and e?e? colliders. We suggest experimental tests for these ideas at colliders and for low-energy observables. (author)

  17. Search for lepton-flavor and lepton-number-violating ? ? ?hh' decay modes

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

    Miyazaki, Y.; Hayasaka, K.; Adachi, I.; Aihara, H.; Asner, D.M.; Aulchenko, V.; Aushev, T.; Bakich, A.M.; Bay, A.; Bhardwaj, V.; et al

    2013-02-01

    We search for lepton-flavor and lepton-number-violating ? decays into a lepton (? = electron or muon) and two charged mesons (h,h'=?± or K±) using 854 fb?¹of data collected with the Belle detector at the KEKB asymmetric-energy e?e? collider. We obtain 90% confidence level upper limits on the ???hh' branching fractions in the range (2.0–8.4)×10??. These results improve upon our previously published upper limits by factors of about 1.8 on average.

  18. Electronic-type vacuum gauges with replaceable elements

    DOE Patents [OSTI]

    Edwards, D. Jr.

    1984-09-18

    In electronic devices for measuring pressures in vacuum systems, the metal elements which undergo thermal deterioration are made readily replaceable by making them parts of a simple plug-in unit. Thus, in ionization gauges, the filament and grid or electron collector are mounted on the novel plug-in unit. In thermocouple pressure gauges, the heater and attached thermocouple are mounted on the plug-in unit. Plug-in units have been designed to function, alternatively, as ionization gauge and as thermocouple gauge, thus providing new gauges capable of measuring broader pressure ranges than is possible with either an ionization gauge or a thermocouple gauge. 5 figs.

  19. Electronic-type vacuum gauges with replaceable elements

    DOE Patents [OSTI]

    Edwards, Jr., David (7 Brown's La., Bellport, NY 11713)

    1984-01-01

    In electronic devices for measuring pressures in vacuum systems, the metal elements which undergo thermal deterioration are made readily replaceable by making them parts of a simple plug-in unit. Thus, in ionization gauges, the filament and grid or electron collector are mounted on the novel plug-in unit. In thermocouple pressure gauges, the heater and attached thermocouple are mounted on the plug-in unit. Plug-in units have been designed to function, alternatively, as ionization gauge and as thermocouple gauge, thus providing new gauges capable of measuring broader pressure ranges than is possible with either an ionization gauge or a thermocouple gauge.

  20. POLE EXPANSION FOR SOLVING A TYPE OF PARAMETRIZED LINEAR SYSTEMS IN ELECTRONIC STRUCTURE

    E-Print Network [OSTI]

    Ying, Lexing

    POLE EXPANSION FOR SOLVING A TYPE OF PARAMETRIZED LINEAR SYSTEMS IN ELECTRONIC STRUCTURE, parametrized linear systems, electronic structure calculation AMS subject classifications. 65F30,65D30,65Z05 1 linear systems. Under certain assumptions on the parametrization, solutions to the linear systems for all

  1. Measurements of heavy quark production via single leptons at PHENIX

    E-Print Network [OSTI]

    Donald Hornback; for the PHENIX Collaboration

    2008-04-30

    The measurement of single leptons from the semi-leptonic decay of heavy-flavor hadrons has long been a means for studying heavy-quark production. PHENIX has measured single muons in pp collisions at forward rapidity and single electrons in both pp and AuAu collisions at mid-rapidity at sqrt(s_NN)=200 GeV. The most recent PHENIX single lepton results are presented in the context of state-of-the-art pQCD calculations. An updated azimuthal anisotropy, v2(pT), measurement for heavy-flavor single electrons in AuAu collisions is also presented.

  2. Transverse self-modulation of ultra-relativistic lepton beams in the plasma wakefield accelerator

    E-Print Network [OSTI]

    Vieira, J; Mori, W B; Silva, L O; Muggli, P

    2015-01-01

    The transverse self-modulation of ultra-relativistic, long lepton bunches in high-density plasmas is explored through full-scale particle-in-cell simulations. We demonstrate that long SLAC-type electron and positron bunches can become strongly self-modulated over centimeter distances, leading to wake excitation in the blowout regime with accelerating fields in excess of 20 GV/m. We show that particles energy variations exceeding 10 GeV can occur in meter-long plasmas. We find that the self-modulation of positively and negatively charged bunches differ when the blowout is reached. Seeding the self-modulation instability suppresses the competing hosing instability. This work reveals that a proof-of-principle experiment to test the physics of bunch self-modulation can be performed with available lepton bunches and with existing experimental apparatus and diagnostics.

  3. Light Leptonic New Physics at the Precision Frontier

    E-Print Network [OSTI]

    Matthias Le Dall

    2015-09-25

    Precision probes of new physics are often interpreted through their indirect sensitivity to short-distance scales. In this proceedings contribution, we focus on the question of which precision observables, at current sensitivity levels, allow for an interpretation via either short-distance new physics or consistent models of long-distance new physics, weakly coupled to the Standard Model. The electroweak scale is chosen to set the dividing line between these scenarios. In particular, we find that inverse see-saw models of neutrino mass allow for light new physics interpretations of most precision leptonic observables, such as lepton universality, lepton flavor violation, but not for the electron EDM.

  4. On the speed and acceleration of electron beams triggering interplanetary type III radio bursts

    E-Print Network [OSTI]

    Krupar, Vratislav; Soucek, Jan; Santolik, Ondrej; Maksimovic, Milan; Kruparova, Oksana

    2015-01-01

    Type III radio bursts are intense radio emissions triggered by beams of energetic electrons often associated with solar flares. These exciter beams propagate outwards from the Sun along an open magnetic field line in the corona and in the interplanetary (IP) medium. We performed a statistical survey of 29 simple and isolated IP type III bursts observed by STEREO/Waves instruments between January 2013 and September 2014. We investigated their time-frequency profiles in order to derive the speed and acceleration of exciter electron beams. We show these beams noticeably decelerate in the IP medium. Obtained speeds range from $\\sim$ 0.02c up to $\\sim$ 0.35c depending on initial assumptions. It corresponds to electron energies between tens of eV and hundreds of keV, and in order to explain the characteristic energies or speeds of type III electrons ($\\sim 0.1$c) observed simultaneously with Langmuir waves at 1 au, the emission of type III bursts near the peak should be predominately at double plasma frequency. Der...

  5. Electronic Durability of Flexible Transparent Films from Type-Specific Single-Wall Carbon Nanotubes

    SciTech Connect (OSTI)

    Harris, J; Iyer, S; Bernhardt, A; Huh, JY; Hudson, S; Fagan, J; Hobbie, E.

    2011-12-11

    The coupling between mechanical flexibility and electronic performance is evaluated for thin films of metallic and semiconducting single-wall carbon nanotubes (SWCNTs) deposited on compliant supports. Percolated networks of type-purified SWCNTs are assembled as thin conducting coatings on elastic polymer substrates, and the sheet resistance is measured as a function of compression and cyclic strain through impedance spectroscopy. The wrinkling topography, microstructure and transparency of the films are independently characterized using optical microscopy, electron microscopy, and optical absorption spectroscopy. Thin films made from metallic SWCNTs show better durability as flexible transparent conductive coatings, which we attribute to a combination of superior mechanical performance and higher interfacial conductivity.

  6. Electronic and optical properties of single excitons and biexcitons in type-II quantum dot nanocrystals

    SciTech Connect (OSTI)

    Koc, Fatih; Sahin, Mehmet E-mail: mehsahin@gmail.com

    2014-05-21

    In this study, a detailed investigation of the electronic and optical properties (i.e., binding energies, absorption wavelength, overlap of the electron-hole wave functions, recombination oscillator strength, etc.) of an exciton and a biexciton in CdTe/CdSe core/shell type-II quantum dot heterostructures has been carried out in the frame of the single band effective mass approximation. In order to determine the electronic properties, we have self-consistently solved the Poisson-Schrödinger equations in the Hartree approximation. We have considered all probable Coulomb interaction effects on both energy levels and also on the corresponding wave functions for both single exciton and biexciton. In addition, we have taken into account the quantum mechanical exchange-correlation effects in the local density approximation between same kinds of particles for biexciton. Also, we have examined the effect of the ligands and dielectric mismatch on the electronic and optical properties. We have used a different approximation proposed by Sahin and Koc [Appl. Phys. Lett. 102, 183103 (2013)] for the recombination oscillator strength of the biexciton for bound and unbound cases. The results obtained have been presented comparatively as a function of the shell thicknesses and probable physical reasons in behind of the results have been discussed in a detail.

  7. Two-stage acceleration of interstellar ions due to the interaction of high-energy lepton plasma flow

    E-Print Network [OSTI]

    Cui, Yun-Qian; Lu, Quan-Ming; Li, Yu-Tong; Zhang, Jie

    2015-01-01

    We present the particle-in-cell (PIC) simulation results of the interaction of a high-energy lepton plasma flow with background electron-proton plasma and focus on the acceleration processes of the protons. It is found that the acceleration follows a two-stage processes. In the first stage, protons are accelerated transversely (perpendicular to the lepton flow) by the turbulent magnetic field "islands" generated via the strong Weibel-type instabilities. The accelerated protons shows a perfect inverse-power energy spectrum. As the interaction continues, a shockwave structure forms and the protons in front of the shockwave are reflected at twice of the shock speed, resulting in a quasi-monoenergetic peak located near 200MeV under the simulation parameters.

  8. Statistical analysis of the dynamics of secondary electrons in the flare of a high-voltage beam-type discharge

    SciTech Connect (OSTI)

    Demkin, V. P.; Mel'nichuk, S. V.

    2014-09-15

    In the present work, results of investigations into the dynamics of secondary electrons with helium atoms in the presence of the reverse electric field arising in the flare of a high-voltage pulsed beam-type discharge and leading to degradation of the primary electron beam are presented. The electric field in the discharge of this type at moderate pressures can reach several hundred V/cm and leads to considerable changes in the kinetics of secondary electrons created in the process of propagation of the electron beam generated in the accelerating gap with a grid anode. Moving in the accelerating electric field toward the anode, secondary electrons create the so-called compensating current to the anode. The character of electron motion and the compensating current itself are determined by the ratio of the field strength to the concentration of atoms (E/n). The energy and angular spectra of secondary electrons are calculated by the Monte Carlo method for different ratios E/n of the electric field strength to the helium atom concentration. The motion of secondary electrons with threshold energy is studied for inelastic collisions of helium atoms and differential analysis is carried out of the collisional processes causing energy losses of electrons in helium for different E/n values. The mechanism of creation and accumulation of slow electrons as a result of inelastic collisions of secondary electrons with helium atoms and selective population of metastable states of helium atoms is considered. It is demonstrated that in a wide range of E/n values the motion of secondary electrons in the beam-type discharge flare has the character of drift. At E/n values characteristic for the discharge of the given type, the drift velocity of these electrons is calculated and compared with the available experimental data.

  9. The Cabibbo angle as a universal seed for quark and lepton mixings

    E-Print Network [OSTI]

    S. Roy; S. Morisi; N. N. Singh; J. W. F. Valle

    2014-10-14

    A model-independent ansatz to describe lepton and quark mixing in a unified way is suggested based upon the Cabibbo angle. In our framework neutrinos mix in a "Bi-Large" fashion, while the charged leptons mix as the "down-type" quarks do. In addition to the standard Wolfenstein parameters (lambda, A) two other free parameters are needed to specify the physical lepton mixing matrix. Through this simple assumption one makes specific predictions for the atmospheric angle as well as leptonic CP violation in good agreement with current observations.

  10. Relating quarks and leptons with the T7 flavour group

    E-Print Network [OSTI]

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

    2014-01-01

    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.

  11. Leptonic mixing, family symmetries, and neutrino phenomenology

    SciTech Connect (OSTI)

    Medeiros Varzielas, I. de [Departamento de Fisica and Centro de Fisica Teorica de Particulas, Instituto Superior Tecnico, Avenida Rovisco Pais, 1049-001 Lisboa (Portugal); Fakultaet fuer Physik, Technische Universitaet Dortmund D-44221 Dortmund (Germany); Gonzalez Felipe, R. [Departamento de Fisica and Centro de Fisica Teorica de Particulas, Instituto Superior Tecnico, Avenida Rovisco Pais, 1049-001 Lisboa (Portugal); Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Emidio Navarro, 1959-007 Lisboa (Portugal); Serodio, H. [Departamento de Fisica and Centro de Fisica Teorica de Particulas, Instituto Superior Tecnico, Avenida Rovisco Pais, 1049-001 Lisboa (Portugal)

    2011-02-01

    Tribimaximal leptonic mixing is a mass-independent mixing scheme consistent with the present solar and atmospheric neutrino data. By conveniently decomposing the effective neutrino mass matrix associated to it, we derive generic predictions in terms of the parameters governing the neutrino masses. We extend this phenomenological analysis to other mass-independent mixing schemes which are related to the tribimaximal form by a unitary transformation. We classify models that produce tribimaximal leptonic mixing through the group structure of their family symmetries in order to point out that there is often a direct connection between the group structure and the phenomenological analysis. The type of seesaw mechanism responsible for neutrino masses plays a role here, as it restricts the choices of family representations and affects the viability of leptogenesis. We also present a recipe to generalize a given tribimaximal model to an associated model with a different mass-independent mixing scheme, which preserves the connection between the group structure and phenomenology as in the original model. This procedure is explicitly illustrated by constructing toy models with the transpose tribimaximal, bimaximal, golden ratio, and hexagonal leptonic mixing patterns.

  12. Tau decays into three charged leptons and two neutrinos

    E-Print Network [OSTI]

    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

    1996-04-01

    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...

  13. Summary of Lepton Photon 2011

    SciTech Connect (OSTI)

    Peskin, Michael E.; /SLAC

    2012-03-14

    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.

  14. Weak scale radiative lepton mass

    SciTech Connect (OSTI)

    Wong, G.; Hou, W. (Department of Physics, National Taiwan University, Taipei, Taiwan 10764 (Taiwan, Province of China))

    1994-09-01

    We construct a [ital Z][sub 8] model for leptons where all Yukawa couplings are of order unity, but known lepton masses are generated radiatively, [ital order] [ital by] [ital order]. The seed is provided by fourth generation leptons [ital E] and [ital N], and two additional Higgs doublets are introduced to give nearest-neighbor Yukawa couplings. Loop masses are generated when [ital Z][sub 8] is [ital softly] broken down to [ital Z][sub 2], while [ital m][sub [ital e

  15. IEEE ELECTRON DEVICE LETTERS, VOL. 31, NO. 8, AUGUST 2010 809 New Process Development for Planar-Type

    E-Print Network [OSTI]

    Dagenais, Mario

    IEEE ELECTRON DEVICE LETTERS, VOL. 31, NO. 8, AUGUST 2010 809 New Process Development for Planar-Type CIC Tunneling Diodes Kwangsik Choi, Filiz Yesilkoy, Athanasios Chryssis, Mario Dagenais, Fellow, IEEE, and Martin Peckerar, Fellow, IEEE Abstract--A planar-type conductor­insulator­conductor tun- neling diode

  16. Electronic branching ratio of the ? lepton

    E-Print Network [OSTI]

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

    1992-06-01

    - duction processes. In addition, it also contained events due to beam interactions with residual gas in the beam pipe ("beam-gas" events). We studied these backgrounds using Monte Carlo techniques and, whenever possible, the data themselves. In the Monte... that the angle between the net momentum of the event and the beam axis, 0„,„„ satisfied ~cos8,„,„,~ (0.80 for events where P~ was less than 0.5 (GeV/c) . Monte Carlo studies indicated that these cuts retained approximately 90% of r pairs satisfy- ing all other...

  17. Elastic stability and electronic structure of pyrite type PtN2: Ahard semiconductor

    SciTech Connect (OSTI)

    Yu, Rong; Zhan, Qian; Zhang, Xiao-Feng

    2006-08-29

    The elastic properties and electronic structure of PtN2 withthe pyrite structure (PtN2(C2)) were studied with first-principlescalculations. The crystal structure is demonstrated to be elasticallystable with a lower energy than the metastable fluorite structureproposed before. The calculated shear modulus of 214 GPa suggests thatPtN2(C2) is harder than some well known hard materials such as TiN andSiC. The high elastic moduli are attributed to a stacking ofcorner-shared PtN6 octahedra bonded by strong N-N covalent bonding. Incontrast to the metallic fluorite-type phase, PtN2(C2) is semiconductingwith an indirect band gap.

  18. Influence of Electronic Type Purity on the Lithiation of Single-Walled Carbon Nanotubes

    SciTech Connect (OSTI)

    Jaber-Ansari, Laila; Iddir, Hakim; Curtiss, Larry A.; Hersam, Mark C.

    2014-03-25

    Single-walled carbon nanotubes (SWCNTs) have emerged as one of the leading additives for high-capacity nanocomposite lithium ion battery electrodes due to their ability to improve electrode conductivity, current collection efficiency, and charge/discharge rate for high power applications. However, since as-grown SWCNTs possess a distribution of physical and electronic structures, it is of high interest to determine which subpopulations of SWCNTs possess the highest lithiation capacity and to develop processing methods that can enhance the lithiation capacity of underperforming SWCNT species. Toward this end, SWCNT electronic type purity is controlled via density gradient ultracentrifugation, enabling a systematic study of the lithiation of SWCNTs as a function of metal versus semiconducting content. Experimentally, vacuum-filtered freestanding films of metallic SWCNTs are found to accommodate lithium with an order of magnitude higher capacity than their semiconducting counterparts, which is consistent with ab initio molecular dynamics and density functional theory calculations in the limit of isolated SWCNTs. In contrast, SWCNT film densification leads to the enhancement of the lithiation capacity of semiconducting SWCNTs to levels comparable to metallic SWCNTs, which is corroborated by theoretical calculations that show increased lithiation of semiconducting SWCNTs in the limit of small SWCNT*SWCNT spacing. Overall, these results will inform ongoing efforts to utilize SWCNTs as conductive additives in nanocomposite lithium ion battery electrodes.

  19. Muon conversion to electron in nuclei in type-I seesaw models

    E-Print Network [OSTI]

    Rodrigo Alonso; Mikael Dhen; Belen Gavela; Thomas Hambye

    2012-10-08

    We compute the muon to electron conversion in the type-I seesaw model, as a function of the right-handed neutrino mixings and masses. The results are compared with previous computations in the literature. We determine the definite predictions resulting for the ratios between the muon to electron conversion rate for a given nucleus and the rate of two other processes which also involve a mu-e flavour transition: mu -> e gamma and mu -> eee. For a quasi-degenerate mass spectrum of right-handed neutrino masses -which is the most natural scenario leading to observable rates- those ratios depend only on the seesaw mass scale, offering a quite interesting testing ground. In the case of sterile neutrinos heavier than the electroweak scale, these ratios vanish typically for a mass scale of order a few TeV. Furthermore, the analysis performed here is also valid down to very light masses. It turns out that planned mu -> e conversion experiments would be sensitive to masses as low as 2 MeV. Taking into account other experimental constraints, we show that future mu -> e conversion experiments will be fully relevant to detect or constrain sterile neutrino scenarios in the 2 GeV-1000 TeV mass range.

  20. IEEE Power Electronics Specialists Conference, PESC-97, 39-45, St. Louis, 1997. A MHz Electronic Ballast for Automotive-Type HID Lamps

    E-Print Network [OSTI]

    Ballast for Automotive-Type HID Lamps Michael Gulko and Sam Ben-Yaakov* Power Electronics Laboratory lamps designated for automotive headlight applications was investigated theoretically, by simulation and experimentally. The study reveals that a based ballast (CS-PPRI) complies with the automotive requirement of very

  1. Nambu--Goldstone Dark Matter and Cosmic Ray Electron and Positron...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BOSONS; ELECTRONS; LEPTONS; NONLUMINOUS MATTER; POSITRONS; RESONANCE; SUPERSYMMETRY...

  2. Tera-Leptons Shadows over Sinister Universe

    E-Print Network [OSTI]

    D. Fargion; M. Khlopov

    2005-07-07

    The role of Sinister Heavy Fermions in recent Glashow's SU(3)*SU(2)*SU(2)'*U(1) model is to offer in a unique frame relic Helium-like products (an ingenious candidate to the dark matter puzzle), a solution to the See-Saw mechanism for light neutrino masses as well as to strong CP violation problem in QCD. The Sinister model requires a three additional families of leptons and quarks, but only the lightest of them Heavy U-quark and E-"electron" are stable. Final neutral Helium-like UUUEE state is an ideal evanescent dark-matter candidate. However it is reached by multi-body interactions along a tail of more manifest secondary frozen blocks. They should be now here polluting the surrounding matter. Moreover, in opposition to effective pair quark annihilations, there is no such an early or late tera-lepton pairs suppressions, because:a) electromagnetic interactions are "weaker" than nuclear ones and b) helium ion 4He++ is able to attract and capture, E-, fixing it into a hybrid tera helium "ion" trap. This leads to a pile up of relic (4HeE)+ traces, a lethal compound for any Sinister Universe. This capture leaves no Tera-Lepton frozen in Ep relic (otherwise an ideal catalyzer to achieve effective late E+E- annihilations possibly saving the model). The (4HeE)+ Coulomb screening is also avoiding the synthesis of the desired UUUEE hidden dark matter gas. The e(4HeE)+ behave chemically like an anomalous hydrogen isotope.Also tera-positronium (eE+) relics are over-abundant and they behave like an anomalous hydrogen atom: these gases do not fit by many orders of magnitude known severe bounds on hydrogen anomalous isotope, making grave shadows over a Sinister Universe. However a surprising and resolver role for Tera-Pions in UHECR astrophysics has been revealed.

  3. Monte Carlo calculations of electron beam quality conversion factors for several ion chamber types

    SciTech Connect (OSTI)

    Muir, B. R.; Rogers, D. W. O.

    2014-11-01

    Purpose: To provide a comprehensive investigation of electron beam reference dosimetry using Monte Carlo simulations of the response of 10 plane-parallel and 18 cylindrical ion chamber types. Specific emphasis is placed on the determination of the optimal shift of the chambers’ effective point of measurement (EPOM) and beam quality conversion factors. Methods: The EGSnrc system is used for calculations of the absorbed dose to gas in ion chamber models and the absorbed dose to water as a function of depth in a water phantom on which cobalt-60 and several electron beam source models are incident. The optimal EPOM shifts of the ion chambers are determined by comparing calculations of R{sub 50} converted from I{sub 50} (calculated using ion chamber simulations in phantom) to R{sub 50} calculated using simulations of the absorbed dose to water vs depth in water. Beam quality conversion factors are determined as the calculated ratio of the absorbed dose to water to the absorbed dose to air in the ion chamber at the reference depth in a cobalt-60 beam to that in electron beams. Results: For most plane-parallel chambers, the optimal EPOM shift is inside of the active cavity but different from the shift determined with water-equivalent scaling of the front window of the chamber. These optimal shifts for plane-parallel chambers also reduce the scatter of beam quality conversion factors, k{sub Q}, as a function of R{sub 50}. The optimal shift of cylindrical chambers is found to be less than the 0.5 r{sub cav} recommended by current dosimetry protocols. In most cases, the values of the optimal shift are close to 0.3 r{sub cav}. Values of k{sub ecal} are calculated and compared to those from the TG-51 protocol and differences are explained using accurate individual correction factors for a subset of ion chambers investigated. High-precision fits to beam quality conversion factors normalized to unity in a beam with R{sub 50} = 7.5 cm (k{sub Q}{sup ?}) are provided. These factors avoid the use of gradient correction factors as used in the TG-51 protocol although a chamber dependent optimal shift in the EPOM is required when using plane-parallel chambers while no shift is needed with cylindrical chambers. The sensitivity of these results to parameters used to model the ion chambers is discussed and the uncertainty related to the practical use of these results is evaluated. Conclusions: These results will prove useful as electron beam reference dosimetry protocols are being updated. The analysis of this work indicates that cylindrical ion chambers may be appropriate for use in low-energy electron beams but measurements are required to characterize their use in these beams.

  4. Radiative Transmission of Lepton Flavor Hierarchies

    E-Print Network [OSTI]

    Adisorn Adulpravitchai; Manfred Lindner; Alexander Merle; Rabindra N. Mohapatra

    2009-08-04

    We discuss a one loop model for neutrino masses which leads to a seesaw-like formula with the difference that the charged lepton masses replace the unknown Dirac mass matrix present in the usual seesaw case. This is a considerable reduction of parameters in the neutrino sector and predicts a strong hierarchical pattern in the right handed neutrino mass matrix that is easily derived from a $U(1)_H$ family symmetry. The model is based on the left-right gauge group with an additional $Z_4$ discrete symmetry which gives vanishing neutrino Dirac masses and finite Majorana masses arising at the one loop level. Furthermore, it is one of the few models that naturally allow for large (but not necessarily maximal) mixing angles in the lepton sector. A generalization of the model to the quark sector requires three iso-spin singlet vector-like down type quarks, as in $E_6$. The model predicts an inert doublet type scalar dark matter.

  5. Lepton and Quark Mixing Patterns from Finite Flavor Symmetries

    E-Print Network [OSTI]

    Chang-Yuan Yao; Gui-Jun Ding

    2015-05-14

    We perform a systematical and analytical study of lepton mixing which can be derived from the subgroups of $SU(3)$ under the assumption that neutrinos are Dirac particles. We find that type D groups can predict lepton mixing patterns compatible with the experimental data at $3\\sigma$ level. The lepton mixing matrix turns out to be of the trimaximal form, and the Dirac CP violating phase is trivial. Moreover, we extend the flavor symmetry to the quark sector. The Cabibbo mixing between the first two generations of quarks can be generated by type D groups. Since all the finite subgroups of $U(3)$ which are not the subgroups of $SU(3)$ have not been classified, an exhaustive scan over all finite discrete groups up to order 2000 is performed with the help of the computer algebra system \\texttt{GAP}. We find that only 90 (10) groups for Dirac (Majorana) neutrinos can generate the lepton mixing angles in the experimentally preferred ranges. The lepton mixing matrix is still the trimaximal pattern and the Dirac CP phase remains trivial. The smallest groups which lead to viable mixing angles are $[162, 10]$, $[162, 12]$ and $[162, 14]$. For quark flavor mixing, the correct order of magnitude of the CKM matrix elements can not be generated. Only the Cabibbo mixing is allowed even if we impose very loose constraints $0.1\\leq|\\left(V_{CKM}\\right)_{12}|\\leq0.3$ and $|\\left(V_{CKM}\\right)_{13}|\\leq|\\left(V_{CKM}\\right)_{23}|right)_{12}|$. The group $\\Delta(6\\cdot7^2)$ can predict a Cabibbo angle $\\theta_q=\\pi/14$ in good agreement with the best fit value. The groups which can give rise to both phenomenologically viable lepton mixing angles and acceptable Cabibbo angle are discussed, and the groups $\\Delta(6\\cdot9^2)$, $[648, 259]$, $[648, 260]$, $[648, 266]$ and $\\Delta(6\\cdot14^2)$ are especially promising.

  6. Search for neutrinoless decays of the ? lepton

    E-Print Network [OSTI]

    Baringer, Philip S.

    1990-02-01

    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...

  7. Testing minimal lepton flavor violation with extra vector-like leptons at the LHC

    E-Print Network [OSTI]

    Eilam Gross; Daniel Grossman; Yosef Nir; Ofer Vitells

    2010-01-17

    Models of minimal lepton flavor violation where the seesaw scale is higher than the relevant flavor scale predict that all lepton flavor violation is proportional to the charged lepton Yukawa matrix. If extra vector-like leptons are within the reach of the LHC, it will be possible to test the resulting predictions in ATLAS/CMS.

  8. Analytical solutions for energy spectra of electrons accelerated by nonrelativistic shock-waves in shell type supernova remnants

    E-Print Network [OSTI]

    V. N. Zirakashvili; F. Aharonian

    2007-10-26

    %context {Recent observations of hard X-rays and very high energy gamma-rays from a number of young shell type supernova remnants indicate the importance of detailed quantitative studies of energy spectra of relativistic electrons formed via diffusive shock acceleration accompanied by intense nonthermal emission through synchrotron radiation and inverse Compton scattering.} %aim {The aim of this work was derivation of exact asymptotic solutions of the kinetic equation which describes the energy distribution of shock-accelerated electrons for an arbitrary energy-dependence of the diffusion coefficient.} %method {The asymptotic solutions at low and very high energy domains coupled with numerical calculations in the intermediate energy range allow analytical presentations of energy spectra of electrons for the entire energy region.} %results {Under the assumption that the energy losses of electrons are dominated by synchrotron cooling, we derived the exact asymptotic spectra of electrons without any restriction on the diffusion coefficient. We also obtained simple analytical approximations which describe, with accuracy better than ten percent, the energy spectra of nonthermal emission of shock-accelerated electrons due to the synchrotron radiation and inverse Compton scattering.} %conclusions {The results can be applied for interpretation of X-ray and gamma-ray observations of shell type supernova remnants, as well as other nonthermal high energy source populations like microquasars and large scale synchrotron jets of active galactic nuclei.

  9. Monte Carlo simulation of baryon and lepton number violating processes at high energies

    E-Print Network [OSTI]

    M. J. Gibbs; A. Ringwald; B. R. Webber; J. T Zadrozny

    1994-06-09

    We report results obtained with the first complete event generator for electroweak baryon and lepton number violating interactions at supercolliders. We find that baryon number violation would be very difficult to establish, but lepton number violation can be seen provided at least a few hundred L violating events are available with good electron or muon identification in the energy range 10 GeV to 1 TeV.

  10. Lepton asymmetry and the cosmic QCD transition

    E-Print Network [OSTI]

    Dominik J Schwarz; Maik Stuke

    2010-09-29

    We study the influence of lepton asymmetry on the evolution of the early Universe. The lepton asymmetry $l$ is poorly constrained by observations and might be orders of magnitude larger than the baryon asymmetry $b$, $|l|/b \\leq 2\\times 10^8$. We find that lepton asymmetries that are large compared to the tiny baryon asymmetry, can influence the dynamics of the QCD phase transition significantly. The cosmic trajectory in the $\\mu_B-T$ phase diagram of strongly interacting matter becomes a function of lepton (flavour) asymmetry. Large lepton asymmetry could lead to a cosmic QCD phase transition of first order.

  11. Indirect Probe of Electroweak-Interacting Particles at Future Lepton Colliders

    E-Print Network [OSTI]

    Harigaya, Keisuke; Kundu, Anirban; Matsumoto, Shigeki; Shirai, Satoshi

    2015-01-01

    Various types of electroweak-interacting particles, which have non-trivial charges under the $\\mathrm{SU}(2)_L \\times \\mathrm{U}(1)_Y$ gauge symmetry, appear in various extensions of the Standard Model. These particles are good targets of future lepton colliders, such as the International Linear Collider (ILC), the Compact LInear Collider (CLIC) and the Future Circular Collider of electrons and positrons (FCC-ee). An advantage of the experiments is that, even if their beam energies are below the threshold of the production of the new particles, quantum effects of the particles can be detected through high precision measurements. We estimate the capability of future lepton colliders to probe electroweak-interacting particles through the quantum effects, with particular focus on the wino, the Higgsino and the so-called minimal dark matters, and found that a particle whose mass is greater than the beam energy by 100-1000 GeV is detectable by measuring di-fermion production cross sections with $O(0.1)$\\% accuracy...

  12. Indirect Probe of Electroweak-Interacting Particles at Future Lepton Colliders

    E-Print Network [OSTI]

    Keisuke Harigaya; Koji Ichikawa; Anirban Kundu; Shigeki Matsumoto; Satoshi Shirai

    2015-04-14

    Various types of electroweak-interacting particles, which have non-trivial charges under the $\\mathrm{SU}(2)_L \\times \\mathrm{U}(1)_Y$ gauge symmetry, appear in various extensions of the Standard Model. These particles are good targets of future lepton colliders, such as the International Linear Collider (ILC), the Compact LInear Collider (CLIC) and the Future Circular Collider of electrons and positrons (FCC-ee). An advantage of the experiments is that, even if their beam energies are below the threshold of the production of the new particles, quantum effects of the particles can be detected through high precision measurements. We estimate the capability of future lepton colliders to probe electroweak-interacting particles through the quantum effects, with particular focus on the wino, the Higgsino and the so-called minimal dark matters, and found that a particle whose mass is greater than the beam energy by 100-1000 GeV is detectable by measuring di-fermion production cross sections with $O(0.1)$\\% accuracy. In addition, with the use of the same analysis, we also discuss the sensitivity of the future colliders to model independent higher dimensional operators, and found that the cutoff scales corresponding to the operators can be probed up to a few ten TeV.

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

    E-Print Network [OSTI]

    Taylor, Frank E.

    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 ...

  14. Gravitating lepton bag model

    E-Print Network [OSTI]

    Burinskii, Alexander

    2015-01-01

    As is known, the gravitational and electromagnetic (EM) field of the Dirac electron is described by an over-extremal Kerr-Newman (KN) black hole (BH) solution which has the naked singular ring and two-sheeted topology. This space is regulated by the formation of a regular source based on the Higgs mechanism of broken symmetry. This source shares much in common with the known MIT- and SLAC-bag models, but has the important advantage, of being in accordance with gravitational and electromagnetic field of the external KN solution. The KN bag model is flexible. At rotations, it takes the shape of a thin disk, and similar to other bag models, under deformations it creates a string-like structure which is positioned along the sharp border of the disk.

  15. Gravitating lepton bag model

    E-Print Network [OSTI]

    Alexander Burinskii

    2015-04-30

    As is known, the gravitational and electromagnetic (EM) field of the Dirac electron is described by an over-extremal Kerr-Newman (KN) black hole (BH) solution which has the naked singular ring and two-sheeted topology. This space is regulated by the formation of a regular source based on the Higgs mechanism of broken symmetry. This source shares much in common with the known MIT- and SLAC-bag models, but has the important advantage, of being in accordance with gravitational and electromagnetic field of the external KN solution. The KN bag model is flexible. At rotations, it takes the shape of a thin disk, and similar to other bag models, under deformations it creates a string-like structure which is positioned along the sharp border of the disk.

  16. Optical and electronic properties of delafossite CuBO{sub 2}p-type transparent conducting oxide

    SciTech Connect (OSTI)

    Ruttanapun, Chesta E-mail: krchesta@kmitl.ac.th

    2013-09-21

    CuBO{sub 2} delafossite was prepared by solid state reaction and calcined/sintered at 1005?°C. The optical properties of this p-type transparent conducting oxide were investigated. Its crystal structure, morphology, composition, oxygen decomposition, and optical and electronic properties were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, thermal gravimetric analysis (TGA), ultraviolet-visible-near-infrared (UV-VIS-NIR) and fluorescence spectroscopies, Seebeck coefficient, and electrical conductivity measurements. CuBO{sub 2} delafossite possesses a hexagonal space group R3{sup ¯}m. TGA indicated a weight loss of 10%, which was attributed to excess oxygen. The positive Seebeck coefficient confirmed p-type behavior. Emission at 355?nm indicated a direct band type transition, and the UV-VIS-NIR spectrum indicated an optical direct gap of 3.6?eV. Activation energies for carrier production and electrical conduction were 0.147 and 0.58?eV, respectively, indicating the thermal activation of carriers. CuBO{sub 2} delafossite is a p-type transparent conducting oxide with a wide band gap and may have potential in industrial p-type electrodes.

  17. CP nonconservation in the leptonic sector

    E-Print Network [OSTI]

    Petre Dita

    2006-09-22

    In this paper we use an exact method to impose unitarity on moduli of the neutrino PMNS matrix recently determined, and show how one could obtain information on CP non-conservation from a limited experimental information. One suggests a novel type of global fit by expressing all the theoretical quantities in terms of convention independent parameters: the Jarlskog invariant $J$ and the moduli $|U_{\\alpha i}|$, able to resolve the positivity problem of $|U_{e 3}|$. In this way the fit will directly provide a value for $J$, and if it is different from zero it will prove the existence of CP violation in the available experimental data. If the best fit result, $|U_{e3}|^2<0$, from M. Maltoni {\\em et al}, New J.Phys. {\\bf 6} (2004) 122 is confirmed, it will imply a new physics in the leptonic sector.

  18. CP nonconservation in the leptonic sector

    E-Print Network [OSTI]

    Petre Dita

    2011-01-21

    In this paper we use an exact method to impose unitarity on moduli of neutrino PMNS matrix recently determined, and show how one could obtain information on CP nonconservation from a limited experimental information. One suggests a novel type of global fit by expressing all theoretical quantities in terms of convention independent parameters: the Jarlskog invariant $J$ and the moduli $|U_{\\alpha i}|$, able to resolve the positivity problem of $|U_{e 3}|$. In this way the fit will directly provide a value for $J$, and if it is different from zero it will prove the existence of CP violation in the available experimental data. If the best fit result, $|U_{e3}|^2<0$, from M. Maltoni {\\em et al}, [New J.Phys. {\\bf 6} (2004) 122] is confirmed, it will imply a new physics in the leptonic sector.

  19. Lepton-mediated electroweak baryogenesis

    SciTech Connect (OSTI)

    Chung, Daniel J. H.; Garbrecht, Bjorn [University of Wisconsin, Madison, Wisconsin, 53706-1390 (United States); Ramsey-Musolf, Michael J. [University of Wisconsin, Madison, Wisconsin, 53706-1390 (United States); California Institute of Technology, Pasadena, California 91125 (United States); Tulin, Sean [California Institute of Technology, Pasadena, California 91125 (United States)

    2010-03-15

    We investigate the impact of the tau and bottom Yukawa couplings on the transport dynamics for electroweak baryogenesis in supersymmetric extensions of the standard model. Although it has generally been assumed in the literature that all Yukawa interactions except those involving the top quark are negligible, we find that the tau and bottom Yukawa interaction rates are too fast to be neglected. We identify an illustrative 'lepton-mediated electroweak baryogenesis' scenario in which the baryon asymmetry is induced mainly through the presence of a left-handed leptonic charge. We derive analytic formulas for the computation of the baryon asymmetry that, in light of these effects, are qualitatively different from those in the established literature. In this scenario, for fixed CP-violating phases, the baryon asymmetry has opposite sign compared to that calculated using established formulas.

  20. Natural fourth generation of leptons

    E-Print Network [OSTI]

    Oleg Antipin; Matti Heikinheimo; Kimmo Tuominen

    2009-09-14

    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.

  1. Electronic Structure of LaOFeP - a Different Type of High Temperature

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas NuclearElectronic Structure and Magnetism inElectronic

  2. Lepton Photon Symposium 2005: Summary and Outlook

    E-Print Network [OSTI]

    Francis Halzen

    2005-11-02

    Lepton Photon 2005 told the saga of the Standard Model which is still exhilarating because it leaves all questions of consequence unanswered.

  3. Search for doubly charged Higgs bosons with lepton-flavour-violating decays involving tau leptons

    SciTech Connect (OSTI)

    Aaltonen, T.

    2007-12-01

    The authors search for pair production of doubly charged Higgs particles (H{sup {+-}{+-}}) followed by decays into electron-tau (e{tau}) and muon-tau ({mu}{tau}) pairs using a data set corresponding to an integrated luminosity of 350 pb{sup -1} collected from {bar p}p collisions at {radical}s = 1.96 TeV by the CDF II experiment. They search separately for cases where three or four final-state leptons are detected, and then combine the results into limits for each exclusive flavor decay mode of the H{sup {+-}{+-}}. Assuming 100% branching ratios of the H{sup {+-}{+-}} to left-handed e{tau} ({mu}{tau}) pairs, they set an H{sup {+-}{+-}} lower mass limit of 114 (112) GeV/c{sup 2} at the 95% confidence level (C.L.).

  4. Table HC2.11 Home Electronics Characteristics by Type of Housing...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    ... 0.7 0.5 Q Q Q Q Type of Monitor Used on Most-Used PC Desk-top CRT (Standard Monitor)... 45.0 32.6 2.5 2.4 5.1 2.4 Flat-panel...

  5. Symmetrical parametrizations of the lepton mixing matrix

    SciTech Connect (OSTI)

    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)

    2011-10-01

    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.

  6. Lepton Flavor Mixing and CP Symmetry

    E-Print Network [OSTI]

    Peng Chen; Cai-Chang Li; Gui-Jun Ding

    2014-12-29

    The strategy of constraining the lepton flavor mixing from remnant CP symmetry is investigated in a rather general way. The neutrino mass matrix generally admits four remnant CP transformations which can be derived from the measured lepton mixing matrix in the charged lepton diagonal basis. Conversely, the lepton mixing matrix can be reconstructed from the postulated remnant CP transformations. All mixing angles and CP violating phases can be completely determined by the full set of remnant CP transformations or three of them. When one or two remnant CP transformations are preserved, the resulting lepton mixing matrix would depend on three real parameters or one real parameter respectively in addition to the parameters characterizing the remnant CP, and the concrete form of the mixing matrix is presented. The phenomenological predictions for the mixing parameters are discussed. The conditions leading to vanishing or maximal Dirac CP violation are studied.

  7. ERL-BASED LEPTON-HADRON COLLIDERS: eRHIC AND LHeC

    E-Print Network [OSTI]

    Zimmermann, F

    2013-01-01

    Two hadron-ERL colliders are being proposed. The Large Hadron electron Collider (LHeC) plans to collide the high-energy protons and heavy ions in the Large Hadron Collider (LHC) at CERN with 60-GeV polarized electrons or positrons. The baseline scheme for this facility adds to the LHC a separate recirculating superconducting (SC) lepton linac with energy recovery, delivering a lepton current of 6.4mA. The electron-hadron collider project eRHIC aims to collide polarized (and unpolarized) electrons with a current of 50 (220) mA and energies in the range 5–30 GeV with a variety of hadron beams— heavy ions as well as polarized light ions— stored in the existing Relativistic Heavy Ion Collider (RHIC) at BNL. The eRHIC electron beam will be generated in an energy recovery linac (ERL) installed inside the RHIC tunnel.

  8. Searches for Leptonic B Decays at BaBar

    SciTech Connect (OSTI)

    Nelson, Silke; /SLAC

    2012-04-25

    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}.

  9. Diffusive Shock Acceleration of Electrons and Radio Emission from Large Diameter Shell-Type Supernova Remnants

    E-Print Network [OSTI]

    A. I. Asvarov

    2000-01-21

    In present study I examine the capability of diffusive shock acceleration mechanism to explain existing data on radio emission from evolved large diameter shell-type adiabatic supernova remnants (SNRs). Time-dependent ''onion-shell'' model for the radio emission of SNRs is developed, which is based on the assumptions: a) acceleration takes place from thermal energies and test-particle approximation is valid; b) the problem of injection is avoided by introducing, like Bell (1978), two injection parameters; c) to take into consideration very late stages of SNR evolution the analytic approximation of Cox and Andersen (1982) for the shell structure is used; c)no radiative cooling. Constructed Surface Brightness - Diameter $(\\Sigma -D)$ tracks are compared with the empirical $\\Sigma -D$ diagram. The main conclusion of the study is that the DSA mechanism is capable of explaining all the statistics of radio SNRs including very large diameter remnants and giant galactic loops.

  10. Search for Pair Production of a Heavy Up-Type Quark Decaying to a W Boson and a b Quark in the lepton+jets Channel with the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for production of a heavy up-type quark (t?) together with its antiparticle, assuming subsequent decay to a W boson and a b quark, t?t? ?-->W[superscript+]bW[superscript -]b? . The search is based on ...

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

    E-Print Network [OSTI]

    Xie, Si

    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 ...

  12. New textures for the lepton mass matrices

    E-Print Network [OSTI]

    P. M. Ferreira; L. Lavoura

    2014-12-02

    We study predictive textures for the lepton mass matrices in which the charged-lepton mass matrix has either four or five zero matrix elements while the neutrino Majorana mass matrix has, respectively, either four or three zero matrix elements. We find that all the viable textures of these two kinds share many predictions: the neutrino mass spectrum is inverted, the sum of the light-neutrino masses is close to 0.1 eV, the Dirac phase $\\delta$ in the lepton mixing matrix is close to either $0$ or $\\pi$, and the mass term responsible for neutrinoless double-beta decay lies in between 12 and 22 meV.

  13. New textures for the lepton mass matrices

    E-Print Network [OSTI]

    Ferreira, P M

    2014-01-01

    We study predictive textures for the lepton mass matrices in which the charged-lepton mass matrix has either four or five zero matrix elements while the neutrino Majorana mass matrix has, respectively, either four or three zero matrix elements. We find that all the viable textures of these two kinds share many predictions: the neutrino mass spectrum is inverted, the sum of the light-neutrino masses is close to 0.1 eV, the Dirac phase $\\delta$ in the lepton mixing matrix is close to either $0$ or $\\pi$, and the mass term responsible for neutrinoless double-beta decay lies in between 12 and 22 meV.

  14. Probing lepton asymmetry with 21 cm fluctuations

    SciTech Connect (OSTI)

    Kohri, Kazunori; Oyama, Yoshihiko [The Graduate University for Advanced Studies (Sokendai), 1-1 Oho, Tsukuba 305-0801 (Japan); Sekiguchi, Toyokazu [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 (Japan); Takahashi, Tomo, E-mail: kohri@post.kek.jp, E-mail: oyamayo@post.kek.jp, E-mail: toyokazu.sekiguchi@helsinki.fi, E-mail: tomot@cc.saga-u.ac.jp [Department of Physics, Saga University, Saga 840-8502 (Japan)

    2014-09-01

    We investigate the issue of how accurately we can constrain the lepton number asymmetry ?{sub ?}=?{sub ?}/T{sub ?} in the Universe by using future observations of 21 cm line fluctuations and cosmic microwave background (CMB). We find that combinations of the 21 cm line and the CMB observations can constrain the lepton asymmetry better than big-bang nucleosynthesis (BBN). Additionally, we also discuss constraints on ?{sub ?} in the presence of some extra radiation, and show that the 21 cm line observations can substantially improve the constraints obtained by CMB alone, and allow us to distinguish the effects of the lepton asymmetry from the ones of extra radiation.

  15. 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]

    Zhukova, Victoria

    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], ...

  16. Search for Supersymmetry in Events with Four or More Leptons in ?s = 8 TeV pp Collisions with the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    Results from a search for supersymmetry in events with four or more leptons including electrons, muons and taus are presented. The analysis uses a data sample corresponding to 20.3??fb[superscript ?1] of proton-proton ...

  17. Lepton Flavor Violating Decays - Review & Outlook

    E-Print Network [OSTI]

    Toshinori Mori

    2006-05-31

    Here I review the status and prospects of experimental investigations into lepton flavor violation (LFV) in charged leptons. Rare LFV processes are naturally expected to occur through loops of TeV scale particles predicted by supersymmetric theories or other models beyond the Standard Model. In contrast to physics of quark flavors that is dominated by the Cabibbo-Kobayashi-Maskawa matrix, LFV in charged leptons is a definitive signal of new physics. Currently active researches are rare tau decay searches at the B factories. The MEG experiment will soon start a sensitive search for the LFV muon decay, mu to e gamma. Prospects for searches at the LHC, a possibility of a fixed target LFV experiment with high energy muons, and a sensitivity of leptonic kaon decays to LFV are also briefly discussed.

  18. Fourth Lepton Family is Natural in Technicolor

    E-Print Network [OSTI]

    Mads T. Frandsen; Isabella Masina; Francesco Sannino

    2009-05-10

    Imagine to discover a new fourth family of leptons at the Large Hadron Collider (LHC) but no signs of an associated fourth family of quarks. What would that imply? An intriguing possibility is that the new fermions needed to compensate for the new leptons gauge anomalies simultaneously address the big hierarchy problem of the Standard Model. A natural way to accomplish such a scenario is to have the Higgs itself be composite of these new fermions. This is the setup we are going to investigate in this paper using as a template Minimal Walking Technicolor. We analyze a general heavy neutrino mass structure with and without mixing with the Standard Model families. We also analyze the LHC potential to observe the fourth lepton family in tandem with the new composite Higgs dynamics. We finally introduce a model uniting the fourth lepton family and the technifermion sector at higher energies.

  19. Electron

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear ProfileMultiferroicAward | DepartmentElectron thermal

  20. Calculation of two-centre two-electron integrals over Slater-type orbitals revisited. I. Coulomb and hybrid integrals

    E-Print Network [OSTI]

    Micha? Lesiuk; Robert Moszynski

    2015-01-08

    In this paper, which constitutes the first part of the series, we consider calculation of two-centre Coulomb and hybrid integrals over Slater-type orbitals (STOs). General formulae for these integrals are derived with no restrictions on the values of the quantum numbers and nonlinear parameters. Direct integration over the coordinates of one of the electrons leaves us with the set of overlap-like integrals which are evaluated by using two distinct methods. The first one is based on the transformation to the ellipsoidal coordinates system and the second utilises a recursive scheme for consecutive increase of the angular momenta in the integrand. In both methods simple one-dimensional numerical integrations are used in order to avoid severe digital erosion connected with the straightforward use of the alternative analytical formulae. It is discussed that the numerical integration does not introduce a large computational overhead since the integrands are well-behaved functions, calculated recursively with decent speed. Special attention is paid to the numerical stability of the algorithms. Applicability of the resulting scheme over a large range of the nonlinear parameters is tested on examples of the most difficult integrals appearing in the actual calculations including at most 7i-type functions (l=6).

  1. Structural studies of P-type ATPase–ligand complexes using an X-ray free-electron laser

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

    Bublitz, Maike; Nass, Karol; Drachmann, Nikolaj D.; Markvardsen, Anders J.; Gutmann, Matthias J.; Barends, Thomas R. M.; Mattle, Daniel; Shoeman, Robert L.; Doak, R. Bruce; Boutet, Sébastien; et al

    2015-06-11

    Membrane proteins are key players in biological systems, mediating signalling events and the specific transport ofe.g.ions and metabolites. Consequently, membrane proteins are targeted by a large number of currently approved drugs. Understanding their functions and molecular mechanisms is greatly dependent on structural information, not least on complexes with functionally or medically important ligands. Structure determination, however, is hampered by the difficulty of obtaining well diffracting, macroscopic crystals. Here, the feasibility of X-ray free-electron-laser-based serial femtosecond crystallography (SFX) for the structure determination of membrane protein–ligand complexes using microcrystals of various native-source and recombinant P-type ATPase complexes is demonstrated. The data revealmore »the binding sites of a variety of ligands, including lipids and inhibitors such as the hallmark P-type ATPase inhibitor orthovanadate. By analyzing the resolution dependence of ligand densities and overall model qualities, SFX data quality metrics as well as suitable refinement procedures are discussed. Even at relatively low resolution and multiplicity, the identification of ligands can be demonstrated. This makes SFX a useful tool for ligand screening and thus for unravelling the molecular mechanisms of biologically active proteins.« less

  2. Structural studies of P-type ATPase–ligand complexes using an X-ray free-electron laser

    SciTech Connect (OSTI)

    Bublitz, Maike; Nass, Karol; Drachmann, Nikolaj D.; Markvardsen, Anders J.; Gutmann, Matthias J.; Barends, Thomas R. M.; Mattle, Daniel; Shoeman, Robert L.; Doak, R. Bruce; Boutet, Sébastien; Messerschmidt, Marc; Seibert, Marvin M.; Williams, Garth J.; Foucar, Lutz; Reinhard, Linda; Sitsel, Oleg; Gregersen, Jonas L.; Clausen, Johannes D.; Boesen, Thomas; Gotfryd, Kamil; Wang, Kai -Tuo; Olesen, Claus; Møller, Jesper V.; Nissen, Poul; Schlichting, Ilme

    2015-06-11

    Membrane proteins are key players in biological systems, mediating signalling events and the specific transport ofe.g.ions and metabolites. Consequently, membrane proteins are targeted by a large number of currently approved drugs. Understanding their functions and molecular mechanisms is greatly dependent on structural information, not least on complexes with functionally or medically important ligands. Structure determination, however, is hampered by the difficulty of obtaining well diffracting, macroscopic crystals. Here, the feasibility of X-ray free-electron-laser-based serial femtosecond crystallography (SFX) for the structure determination of membrane protein–ligand complexes using microcrystals of various native-source and recombinant P-type ATPase complexes is demonstrated. The data reveal the binding sites of a variety of ligands, including lipids and inhibitors such as the hallmark P-type ATPase inhibitor orthovanadate. By analyzing the resolution dependence of ligand densities and overall model qualities, SFX data quality metrics as well as suitable refinement procedures are discussed. Even at relatively low resolution and multiplicity, the identification of ligands can be demonstrated. This makes SFX a useful tool for ligand screening and thus for unravelling the molecular mechanisms of biologically active proteins.

  3. Exotic Leptons. Higgs, Flavor and Collider Phenomenology

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

    Altmannshofer, Wolfgang; Bauer, Martin; Carena, Marcela

    2014-01-15

    We study extensions of the standard model by one generation of vector-like leptons with non-standard hypercharges, which allow for a sizable modification of the h ? ?? decay rate for new lepton masses in the 300 GeV-1 TeV range. We also analyze vacuum stability implications for different hypercharges. Effects in h ? Z? are typically much smaller than in h ? ??, but distinct among the considered hypercharge assignments. Non-standard hypercharges constrain or entirely forbid possible mixing operators with standard model leptons. As a consequence, the leading contributions to the experimentally strongly constrained electric dipole moments of standard model fermionsmore »are only generated at the two loop level by the new CP violating sources of the considered setups. Furthermore, we derive the bounds from dipole moments, electro-weak precision observables and lepton flavor violating processes, and discuss their implications. Finally, we examine the production and decay channels of the vector-like leptons at the LHC, and find that signatures with multiple light leptons or taus are already probing interesting regions of parameter space.« less

  4. Search for anomalous production of multiple leptons in association with $W$ and $Z$ bosons at CDF

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Texas A-M

    2012-02-01

    This paper presents a search for anomalous production of multiple low-energy leptons in association with a W or Z boson using events collected at the CDF experiment corresponding to 5.1 fb{sup -1} of integrated luminosity. This search is sensitive to a wide range of topologies with low-momentum leptons, including those with the leptons near one another. The observed rates of production of additional electrons and muons are compared with the standard model predictions. No indications of phenomena beyond the standard model are found. A 95% confidence level limit is presented on the production cross section for a benchmark model of supersymmetric hidden-valley Higgs production. Particle identification efficiencies are also provided to enable the calculation of limits on additional models.

  5. Comparison of crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te nanocrystalline thin films: Effects of homogeneous irradiation with an electron beam

    SciTech Connect (OSTI)

    Takashiri, Masayuki, E-mail: takashiri@tokai-u.jp; Imai, Kazuo; Uyama, Masato; Nishi, Yoshitake [Department of Materials Science, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Hagino, Harutoshi; Miyazaki, Koji [Department of Mechanical and Control Engineering, Kyushu Institute of Technology, 1-1 Sensui, Tobata-ku, Kitakyushu 804-8550 (Japan); Tanaka, Saburo [Department of Mechanical Engineering, College of Engineering, Nihon University, Nakagawara, Tokusada, Tamuramachi, Koriyama, Fukushima 963-8642 (Japan)

    2014-06-07

    The effects of homogenous electron beam (EB) irradiation on the crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te thin films were investigated. Both types of thin films were prepared by flash evaporation, after which homogeneous EB irradiation was performed at an acceleration voltage of 0.17?MeV. For the n-type thin films, nanodots with a diameter of less than 10?nm were observed on the surface of rice-like nanostructures, and crystallization and crystal orientation were improved by EB irradiation. The resulting enhancement of mobility led to increased electrical conductivity and thermoelectric power factor for the n-type thin films. In contrast, the crystallization and crystal orientation of the p-type thin films were not influenced by EB irradiation. The carrier concentration increased and mobility decreased with increased EB irradiation dose, possibly because of the generation of defects. As a result, the thermoelectric power factor of p-type thin films was not improved by EB irradiation. The different crystallization behavior of the n-type and p-type thin films is attributed to atomic rearrangement during EB irradiation. Selenium in the n-type thin films is more likely to undergo atomic rearrangement than the other atoms present, so only the crystallinity of the n-type Bi-Se-Te thin films was enhanced.

  6. GaInN light-emitting diodes using separate epitaxial growth for the p-type region to attain polarization-inverted electron-blocking layer, reduced electron leakage, and improved hole injection

    SciTech Connect (OSTI)

    Meyaard, David S., E-mail: meyaad@rpi.edu; Lin, Guan-Bo; Ma, Ming; Fred Schubert, E. [Future Chips Constellation, Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)] [Future Chips Constellation, Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Cho, Jaehee [Future Chips Constellation, Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States) [Future Chips Constellation, Department of Electrical, Computer, and Systems Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Semiconductor Physics Research Center, School of Semiconductor and Chemical Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Han, Sang-Heon; Kim, Min-Ho; Shim, HyunWook; Sun Kim, Young [LED Business, Samsung Electronics, Yongin 446-920 (Korea, Republic of)] [LED Business, Samsung Electronics, Yongin 446-920 (Korea, Republic of)

    2013-11-11

    A GaInN light-emitting diode (LED) structure is analyzed that employs a separate epitaxial growth for the p-type region, i.e., the AlGaN electron-blocking layer (EBL) and p-type GaN cladding layer, followed by wafer or chip bonding. Such LED structure has a polarization-inverted EBL and allows for uncompromised epitaxial-growth optimization of the p-type region, i.e., without the need to consider degradation of the quantum-well active region during p-type region growth. Simulations show that such an LED structure reduces electron leakage, reduces the efficiency droop, improves hole injection, and has the potential to extend high efficiencies into the green spectral region.

  7. Sneutrino Higgs models explain lepton non-universality in eejj, e?jj excesses

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

    Berger, Joshua; Dror, Jeff Asaf; Ng, Wee Hao

    2015-09-23

    Recent searches for first-generation leptoquarks and heavy right-handed WR bosons have seen excesses in final states with electrons and jets. A bizarre property of these excesses is that they appear to violate lepton universality. With these results in mind, we study the phenomenology of supersymmetric models in which the Higgs arises as the sneutrino in an electron supermultiplet. Since the electron is singled out in this approach, one can naturally account for the lepton flavor structure of the excesses. In this work, we show that in such a framework, one can significantly alleviate the tension between the Standard Model andmore »the data and yet evade current constraints from other searches. Finally we point out that correlated excesses are expected to be seen in future multilepton searches.« less

  8. Lepton universality test in the photoproduction of $e^- e^+$ versus $?^- ?^+$ pairs on a proton target

    E-Print Network [OSTI]

    Vladyslav Pauk; Marc Vanderhaeghen

    2015-03-04

    In view of the significantly different proton charge radius extracted from muonic hydrogen Lamb shift measurements as compared to electronic hydrogen spectroscopy or electron scattering experiments, we study in this work the photoproduction of a lepton pair on a proton target in the limit of very small momentum transfer as a way to provide a test of the lepton universality when extracting the proton charge form factor. By detecting the recoiling proton in the $\\gamma p \\to l^- l^+ p$ reaction, we show that a measurement of a ratio of $e^-e^+ + \\mu^-\\mu^+$ over $e^-e^+$ cross sections with a relative precision of around 2%, would allow for a test to distinguish between the two different proton charge radii currently extracted from muonic and electronic observables.

  9. Sneutrino Higgs models explain lepton non-universality in CMS excesses

    E-Print Network [OSTI]

    Joshua Berger; Jeff Asaf Dror; Wee Hao Ng

    2015-07-08

    Recent searches for first-generation leptoquarks and heavy right-handed $W_R$ bosons have seen excesses in final states with electrons and jets. A bizarre property of these excesses is that they appear to violate lepton universality. With these results in mind, we study the phenomenology of supersymmetric models in which the Higgs arises as the sneutrino in an electron supermultiplet. Since the electron is singled out in this approach, one can naturally account for the lepton flavor structure of the excesses. In this work, we show that in such a framework, one can significantly alleviate the tension between the Standard Model and the data and yet evade current constraints from other searches. Lastly we point out that correlated excesses are expected to be seen in future multilepton searches.

  10. Direct electron pair production in. pi. /sup -/p interactions at 16 GeV/c and a model for direct lepton and photon production at low P/sub T/

    SciTech Connect (OSTI)

    Blockus, D.; Dunwoodie, W.; Leith, D.W.G.S.

    1981-07-01

    The production of prompt electron-positron pairs in 16 GeV/c ..pi../sup -/p collisions has been measured using the LASS spectrometer at SLAC. An excess of events is observed above the estimated contributions of direct and Dalitz decay of known resonances in the kinematic range defined by 0.1 less than or equal to x less than or equal to 0.45, 0 less than or equal to P/sub T/ less than or equal to 0.8 GeV/c and 0.2 less than or equal to M(e/sup +/e/sup -/) less than or equal to 0.7 GeV/c/sup 2/. The excess signal decreases slowly with increasing M, but exhibits very steep x and P/sub T//sup 2/ dependence. The contribution of this signal to the e/sup +/e/sup -//..pi../sup +/..pi../sup -/ and ..gamma../..pi.. ratios is discussed. Detailed comparisons are made between e/sup +/e/sup -/ distributions and the corresponding low mass ..mu../sup +/..mu../sup -/ distributions, and a simple production mechanism is proposed which describes the 16 GeV/c data well. The implications for direct photon production are presented, and it is shown that the model provides simultaneously a good description of the experimental data on the (e/..pi..) and (..mu../..pi..) ratios for p/sub T/ < 1 GeV/c.

  11. The Lepton Sector of a Fourth Generation

    E-Print Network [OSTI]

    Gustavo Burdman; Leandro Da Rold; Ricardo D. Matheus

    2010-05-10

    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.

  12. Lepton flavor violation in Higgs boson decays under the rare...

    Office of Scientific and Technical Information (OSTI)

    Lepton flavor violation in Higgs boson decays under the rare tau decay results Citation Details In-Document Search Title: Lepton flavor violation in Higgs boson decays under the...

  13. Probing lepton number violation on three frontiers

    SciTech Connect (OSTI)

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

    2013-12-30

    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.

  14. Limits on tau lepton flavor violating decays in three charged leptons

    SciTech Connect (OSTI)

    Cervelli, Alberto

    2010-04-29

    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.

  15. Tau Lepton Production in ep Collisions at HERA

    E-Print Network [OSTI]

    H1 Collaboration

    2006-04-11

    The production of tau leptons in ep collisions is investigated using data recorded by the H1 detector at HERA in the period 1994-2000. Tau leptons are identified by detecting their decay products, using leptonic and hadronic decay modes. The cross section for the production of tau lepton pairs is measured for the first time at HERA. Furthermore, a search for events with an energetic isolated tau lepton and with large missing transverse momentum is performed. The results are found to be in agreement with the Standard Model predictions.

  16. PHYSICAL REVIEW B 83, 245420 (2011) Stone-Wales-type transformations in carbon nanostructures driven by electron irradiation

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    2011-01-01

    driven by electron irradiation J. Kotakoski,1,* J. C. Meyer,2, S. Kurasch,2 D. Santos-Cottin,1 U. Kaiser of carbon nanostructures are at odds with the equilibrium thermodynamics of these systems. Here displacements. We further study the mechanisms of irradiation- driven bond rotations and explain why electron

  17. The Effect of Lepton Mass on the Energy and Bond Length of the Hydrogen Molecule Ion Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    The Effect of Lepton Mass on the Energy and Bond Length of the Hydrogen Molecule Ion Frank Rioux geometry (bond length) and energy of the hydrogen molecule ion. The electron has several heavy weight). The molecular orbital for the hydrogen molecule ion is formed as a linear combination of scaled hydrogenic 1s

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

    E-Print Network [OSTI]

    Istvan Danko; for the CLEO Collaboration

    2006-01-18

    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.

  19. Leptonic Decays of Charged Pseudoscalar Mesons - 2015

    E-Print Network [OSTI]

    Jonathan L. Rosner; Sheldon Stone; Ruth S. Van de Water

    2015-09-07

    We review the physics of purely leptonic decays of $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of the constituent quarks and a strong interaction parameter related to the overlap of the quark and antiquark wave-functions in the meson, called the decay constant $f_P$. The leptonic decay constants for $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ mesons can be obtained with controlled theoretical uncertainties and high precision from {\\it ab initio} lattice-QCD simulations. The combination of experimental leptonic decay-rate measurements and theoretical decay-constant calculations enables the determination of several elements of the CKM matrix within the standard model. These determinations are competitive with those obtained from semileptonic decays, and also complementary because they are sensitive to different quark flavor-changing currents. They can also be used to test the unitarity of the first and second rows of the CKM matrix. Conversely, taking the CKM elements predicted by unitarity, one can infer "experimental" values for $f_P$ that can be compared with theory. These provide tests of lattice-QCD methods, provided new-physics contributions to leptonic decays are negligible at the current level of precision. This review is the basis of the article in the Particle Data Group's 2016 edition, updating the versions in Refs. [1-3].

  20. Lepton sector of a fourth generation

    SciTech Connect (OSTI)

    Burdman, G. [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil); Da Rold, L. [Centro Atomico Bariloche, Bariloche (Argentina); Matheus, R. D. [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil)

    2010-09-01

    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 choosing 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.

  1. Leptonic Decays of Charged Pseudoscalar Mesons - 2015

    E-Print Network [OSTI]

    Rosner, Jonathan L; Van de Water, Ruth S

    2015-01-01

    We review the physics of purely leptonic decays of $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of the constituent quarks and a strong interaction parameter related to the overlap of the quark and antiquark wave-functions in the meson, called the decay constant $f_P$. The leptonic decay constants for $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ mesons can be obtained with controlled theoretical uncertainties and high precision from {\\it ab initio} lattice-QCD simulations. The combination of experimental leptonic decay-rate measurements and theoretical decay-constant calculations enables the determination of several elements of the CKM matrix within the standard model. These determinations are competitive with those obtained from semileptonic decays, and also complementary because they are sensitive to different quark flavor-changing currents. They can also be use...

  2. Doping dependence and anisotropy of minority electron mobility in molecular beam epitaxy-grown p type GaInP

    SciTech Connect (OSTI)

    Haegel, N. M.; Christian, T.; Norman, A. G.; Mascarenhas, A.; Scandrett, C.; Misra, Pranob; Liu, Ting; Sukiasyan, Arsen; Pickett, Evan; Yuen, Homan

    2014-11-17

    Direct imaging of minority electron transport via the spatially resolved recombination luminescence signature has been used to determine carrier diffusion lengths in GaInP as a function of doping. Minority electron mobility values are determined by performing time resolved photoluminescence measurements of carrier lifetime on the same samples. Values at 300?K vary from ?2000 to 400?cm{sup 2}/V?s and decrease with increasing doping. Anisotropic diffusion lengths and strongly polarized photoluminescence are observed, resulting from lateral composition modulation along the [110] direction. We report anisotropic mobility values associated with carrier transport parallel and perpendicular to the modulation direction.

  3. Model independent interpretation of recent CR lepton data after AMS-02

    SciTech Connect (OSTI)

    Gaggero, Daniele; Maccione, Luca E-mail: luca.maccione@lmu.de

    2013-12-01

    We model the CR leptonic fluxes above 20 GeV in terms of a superposition of a standard and a charge symmetric extra component, which we generically describe as power-laws in momentum. We investigate under these hypotheses the compatibility between AMS-02, Fermi-LAT and PAMELA datasets on positron fraction, electron+positron spectrum and electron spectrum respectively. We find that it is possible to reconcile AMS and Fermi-LAT data within uncertainties, if energy-dependent effects are present in Fermi-LAT systematics. We also study possible deviations from charge symmetry in the extra component and find no compelling evidence for them.

  4. Measurement of Hadron and Lepton-Pair Production in e+e- Collisions at sqrt{s}=192-208GeV at LEP

    E-Print Network [OSTI]

    L3 Collaboration

    2006-03-10

    Hadron production and lepton-pair production in e+e- collisions are studied with data collected with the L3 detector at LEP at centre-of-mass energies sqrt{s}=192-208GeV. Using a total integrated luminosity of 453/pb, 36057 hadronic events and 12863 lepton-pair events are selected. The cross sections for hadron production and lepton-pair production are measured for the full sample and for events where no high-energy initial-state-radiation photon is emitted prior to the collisions. Lepton-pair events are further investigated and forward-backward asymmetries are measured. Finally, the differential cross sections for electron-positron pair-production is determined as a function of the scattering angle. An overall good agreement is found with Standard Model predictions.

  5. Leptophobic boson signals with leptons, jets and missing energy

    E-Print Network [OSTI]

    Dobrescu, Bogdan A

    2015-01-01

    Color-singlet gauge bosons with renormalizable couplings to quarks but not to leptons must interact with additional fermions ("anomalons") required to cancel the gauge anomalies. Analyzing the decays of such leptophobic bosons into anomalons, I show that they produce final states involving leptons at the LHC. Resonant production of a flavor-universal leptophobic $Z'$ boson leads to cascade decays via anomalons, whose signatures include a leptonically decaying $Z$, missing energy and several jets. A $Z'$ boson that couples to the right-handed quarks of the first and second generations undergoes cascade decays that violate lepton universality and include signals with two leptons and jets, or with a Higgs boson, a lepton, a $W$ and missing energy.

  6. Dependence of the Electron Beam Energy and Types of Surface to Determine EBSD Indexing Reliability in Yttria-Stabilized Zirconia

    SciTech Connect (OSTI)

    Saraf, Laxmikant V.

    2012-04-01

    Electron backscatter diffraction (EBSD) is a powerful technique for the surface microstructure analysis. EBSD analysis of cubic yttria-stabilized zirconia (YSZ) in two and three dimensions (2-D, 3-D) is demonstrated using sequential slicing from a focused ion beam (FIB) followed by EBSD mapping to represent 3-D reconstructed high density grain structure with random orientation. The statistics related to accuracy of EBSD band detection shows that probability of accurate grain orientation detection increased significantly when the electron beam energy is increased from 10 kV to 30 kV. As a result of better sampling with increased interaction volume, a disparity between local and average grain orientation angle also exhibited the dependence of the electron beam energy to determine the accuracy of grain orientation. To study the accuracy and quality of EBSD band detection as a function of surface roughness and over layer formation, rapid EBSD measurement tests are performed on (a) YSZ surfaces ion-polished at ion beam energies of 65 nA at 30 kV and 1 nA at 30 kV and (b) carbon coated versus uncoated YSZ surfaces. The EBSD results at both 10 kV and 30 kV electron beam energies indicate that EBSD band detection accuracy is negatively affected by surface roughness and amorphous over layer formation.

  7. Constraints on Non-Standard Neutrino Interactions and Unparticle Physics with Neutrino-Electron Scattering at the Kuo-Sheng Nuclear Power Reactor

    E-Print Network [OSTI]

    M. Deniz er al.; TEXONO Collaboration

    2010-08-09

    Neutrino-electron scatterings are purely leptonic processes with robust Standard Model (SM) predictions. Their measurements can therefore provide constraints to physics beyond SM. The $\

  8. Constraints on Non-Standard Neutrino Interactions and Unparticle Physics with Neutrino-Electron Scattering at the Kuo-Sheng Nuclear Power Reactor

    E-Print Network [OSTI]

    al., M Deniz er

    2010-01-01

    Neutrino-electron scatterings are purely leptonic processes with robust Standard Model (SM) predictions. Their measurements can therefore provide constraints to physics beyond SM. The $\

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

    E-Print Network [OSTI]

    D0 Collaboration

    2012-05-16

    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.

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

    E-Print Network [OSTI]

    D0 Collaboration

    2013-01-28

    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.

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

    SciTech Connect (OSTI)

    Abazov, V. M.; et al.

    2013-09-01

    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.

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

    SciTech Connect (OSTI)

    Abazov, Victor Mukhamedovich; et al.

    2012-08-01

    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.

  13. Exploring new physics through contact interactions in lepton...

    Office of Scientific and Technical Information (OSTI)

    Conference: Exploring new physics through contact interactions in lepton pair production at a linear collider Citation Details In-Document Search Title: Exploring new physics...

  14. Lepton universality violation and lepton flavor conservation in $B$-meson decays

    E-Print Network [OSTI]

    Rodrigo Alonso; Benjamín Grinstein; Jorge Martin Camalich

    2015-05-19

    Anomalies in (semi)leptonic $B$-meson decays present interesting patterns that might be revealing the shape of the new physics to come. In order to understand the experimental data, we explore symmetry arguments that lead to the hypothesis of minimal flavor violation. In particular, under the assumption of negligible neutrino mass effects in charged lepton processes, the presence of lepton universality violation without lepton flavor violation naturally arises. This can account for a deficit of $B^+\\to K^+\\mu\\mu$ over $B^+\\to K^+ee$ decays with new physics coupled predominantly to muons and a new physics scale of a few TeV. A prediction of this scenario is the modification of processes involving the third generation. In particular, accounting for the above ratio implies a large enhancement, by a factor $\\sim10^3$ with respect to the standard model, of all the $b\\to s\\tau\\tau$ decay rates. Although these are still below current experimental limits, they should be easily at reach in future experiments at $B$-factories. Another important consequence is the prediction of sizable effects in charge-current $B$ tauonic decays which could also explain the enhancements that have been observed in the $B\\to D^{(*)}\\tau\\bar \

  15. Tensor mesons produced in tau lepton decays

    SciTech Connect (OSTI)

    Lopez Castro, G.; Munoz, J. H.

    2011-05-01

    Light tensor mesons (T=a{sub 2}, f{sub 2} and K{sub 2}*) can be produced in decays of {tau} leptons. In this paper we compute the branching ratios of {tau}{yields}T{pi}{nu} decays by assuming the dominance of intermediate virtual states to model the form factors involved in the relevant hadronic matrix elements. The exclusive f{sub 2}(1270){pi}{sup -} decay mode turns out to have the largest branching ratio, of O(10{sup -4}). Our results indicate that the contribution of tensor meson intermediate states to the three-pseudoscalar channels of {tau} decays are rather small.

  16. The structural, electronic and dynamic properties of the L1{sub 2}- type Co{sub 3}Ti alloy

    SciTech Connect (OSTI)

    Arikan, Nihat; Özduran, Mustafa

    2014-10-06

    The structural, electronic and dynamic properties of the cubic Co{sub 3}Ti alloy in L1{sub 2} structure have been investigated using a pseudopotential plane wave (PP-PW) method within the generalized gradient approximation proposed by Perdew–Burke–Ernzerhof (GGA-PBE). The structural properties, including the lattice constant, the bulk modulus and its pressure derivative agree reasonably with the previous results. The density of state (DOS), projected density of state (PDOS) and electronic band structure are also reported. The DOS shows that Co{sub 3}Ti alloy has a metallic character since the energy bands cross the Fermi level. The density of states at Fermi level mainly comes from the Co-3d states. Phonon dispersion curves and their corresponding total densities of states were obtained using a linear response in the framework of the density functional perturbation theory. All computed phonon frequencies are no imaginer and thus, Co{sub 3}Ti alloy is dynamically stable. The zone center phonon modes have been founded to be 9.307, 9.626 and 13.891 THz for Co{sub 3}Ti.

  17. INCIDENT CONTAMINATION LEPTON DOSES MEASURED USING RADIOCHROMIC FILM IN

    E-Print Network [OSTI]

    Yu, Peter K.N.

    INCIDENT CONTAMINATION LEPTON DOSES MEASURED USING RADIOCHROMIC FILM IN RADIOTHERAPY MARTIN J) AbstractÐMeasurement of lepton contamination is achieved across a radiotherapy photon beam and peripheral in air to measure incident contamination without the eects of phantom scatter. Surface dose was measured

  18. First search for CP violation in tau lepton decay

    E-Print Network [OSTI]

    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.

    1998-11-01

    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...

  19. Detecting Exotic Heavy Leptons at the Large Hadron Collider

    E-Print Network [OSTI]

    B. C. Allanach; C. M. Harris; M. A. Parker; P. Richardson; B. R. Webber

    2001-08-10

    New almost-degenerate charged and neutral heavy leptons are a feature of a number of theories of physics beyond the Standard Model. The prospects for detecting these at the Large Hadron Collider using a time-of-flight technique are considered, along with any cosmological or experimental constraints on their masses. Based on a discovery criterion of 10 detected exotic leptons we conclude that, with an integrated luminosity of 100 fb-1, it should be possible to detect such leptons provided their masses are less than 950 GeV. It should also be possible to use the angular distribution of the produced particles to distinguish these exotic leptons from supersymmetric scalar leptons, at a better than 90% confidence level, for masses up to 580 GeV.

  20. New Paradigm for Baryon and Lepton Number Violation

    E-Print Network [OSTI]

    Pavel Fileviez Perez

    2015-08-17

    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.

  1. Top quark pair production cross section in the lepton+jets channel using b-tagging at D0

    SciTech Connect (OSTI)

    Yoo, H.D.; /Brown U.

    2008-05-01

    The top quark pair production cross section measurement in the lepton+jets channel with b-tagging algorithm is described. About 900 pb{sup -1} data collected by the D0 detector at the Fermilab Tevatron are used for this analysis. In this thesis, event selection, background estimation, and cross section calculation are discussed in detail. In addition, calibration of the Luminosity Monitor readout electronics and a new b-tagging algorithm, the SLTNN tagger, are also discussed in this thesis.

  2. Search for high-mass states with one lepton plus missing transverse momentum in proton–proton collisions at ?s = 7 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector is used to search for high-mass states, such as heavy charged gauge bosons (W?,W*), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp ...

  3. Lepton Number Violation and the Baryon Asymmetry of the Universe

    E-Print Network [OSTI]

    Harz, Julia; Päs, Heinrich

    2015-01-01

    Neutrinoless double beta decay, lepton number violating collider processes and the Baryon Asymmetry of the Universe (BAU) are intimately related. In particular lepton number violating processes at low energies in combination with sphaleron transitions will typically erase any pre-existing baryon asymmetry of the Universe. In this contribution we briefly review the tight connection between neutrinoless double beta decay, lepton number violating processes at the LHC and constraints from successful baryogenesis. We argue that far-reaching conclusions can be drawn unless the baryon asymmetry is stabilized via some newly introduced mechanism.

  4. Search for vectorlike B quarks in events with one isolated lepton, missing transverse momentum, and jets at ?s = 8 TeV with the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O.?S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2015-06-19

    A search has been performed for pair production of heavy vectorlike down-type (B) quarks. The analysis explores the lepton-plus-jets final state, characterized by events with one isolated charged lepton (electron or muon), significant missing transverse momentum, and multiple jets. One or more jets are required to be tagged as arising from b quarks, and at least one pair of jets must be tagged as arising from the hadronic decay of an electroweak boson. The analysis uses the full data sample of pp collisions recorded in 2012 by the ATLAS detector at the LHC, operating at a center-of-mass energy of 8more »TeV, corresponding to an integrated luminosity of 20.3 fb?¹. No significant excess of events is observed above the expected background. Limits are set on vectorlike B production, as a function of the B branching ratios, assuming the allowable decay modes are B ? Wt/Zb/Hb. In the chiral limit with a branching ratio of 100% for the decay B ? Wt, the observed (expected) 95% C.L. lower limit on the vectorlike B mass is 810 GeV (760 GeV). In the case where the vectorlike B quark has branching ratio values corresponding to those of an SU(2) singlet state, the observed (expected) 95% C.L. lower limit on the vectorlike B mass is 640 GeV (505 GeV). The same analysis, when used to investigate pair production of a colored, charge 5/3 exotic fermion T5/3, with subsequent decay T5/3 ? Wt, sets an observed (expected) 95% C.L. lower limit on the T5/3 mass of 840 GeV (780 GeV).« less

  5. Search for vectorlike B quarks in events with one isolated lepton, missing transverse momentum, and jets at ?s = 8 TeV with the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O.?S.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B.?S.; Adamczyk, L.; Adams, D.?L.; Adelman, J.; Adomeit, S.; Adye, T.; Affolder, A.?A.; Agatonovic-Jovin, T.; Aguilar-Saavedra, J.?A.; Agustoni, M.; Ahlen, S.?P.; Ahmadov, F.; Aielli, G.; Akerstedt, H.; Åkesson, T.?P.?A.; Akimoto, G.; Akimov, A.?V.; Alberghi, G.?L.; Albert, J.; Albrand, S.; Alconada Verzini, M.?J.; Aleksa, M.; Aleksandrov, I.?N.; Alexa, C.; Alexander, G.; Alexopoulos, T.; Alhroob, M.; Alimonti, G.; Alio, L.; Alison, J.; Alkire, S.?P.; Allbrooke, B.?M.?M.; Allport, P.?P.; Aloisio, A.; Alonso, A.; Alonso, F.; Alpigiani, C.; Altheimer, A.; Alvarez Gonzalez, B.; Álvarez Piqueras, D.; Alviggi, M.?G.; Amako, K.; Amaral Coutinho, Y.; Amelung, C.; Amidei, D.; Amor Dos Santos, S.?P.; Amorim, A.; Amoroso, S.; Amram, N.; Amundsen, G.; Anastopoulos, C.; Ancu, L.?S.; Andari, N.; Andeen, T.; Anders, C.?F.; Anders, G.; Anderson, K.?J.; Andreazza, A.; Andrei, V.; Angelidakis, S.; Angelozzi, I.; Anger, P.; Angerami, A.; Anghinolfi, F.; Anisenkov, A.?V.; Anjos, N.; Annovi, A.; Antonelli, M.; Antonov, A.; Antos, J.; Anulli, F.; Aoki, M.; Aperio Bella, L.; Arabidze, G.; Arai, Y.; Araque, J.?P.; Arce, A.?T.?H.; Arduh, F.?A.; Arguin, J-F.; Argyropoulos, S.; Arik, M.; Armbruster, A.?J.; Arnaez, O.; Arnal, V.; Arnold, H.; Arratia, M.; Arslan, O.; Artamonov, A.; Artoni, G.; Asai, S.; Asbah, N.; Ashkenazi, A.; Åsman, B.; Asquith, L.; Assamagan, K.; Astalos, R.; Atkinson, M.; Atlay, N.?B.; Auerbach, B.; Augsten, K.; Aurousseau, M.; Avolio, G.; Axen, B.; Ayoub, M.?K.; Azuelos, G.; Baak, M.?A.; Baas, A.?E.; Bacci, C.; Bachacou, H.; Bachas, K.; Backes, M.; Backhaus, M.; Badescu, E.; Bagiacchi, P.; Bagnaia, P.; Bai, Y.; Bain, T.; Baines, J.?T.; Baker, O.?K.; Balek, P.; Balestri, T.; Balli, F.; Banas, E.; Banerjee, Sw.; Bannoura, A.?A.?E.; Bansil, H.?S.; Barak, L.; Baranov, S.?P.; Barberio, E.?L.; Barberis, D.; Barbero, M.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.; Barnes, S.?L.; Barnett, B.?M.; Barnett, R.?M.; Barnovska, Z.; Baroncelli, A.; Barone, G.; Barr, A.?J.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Bartoldus, R.; Barton, A.?E.; Bartos, P.; Bassalat, A.; Basye, A.; Bates, R.?L.; Batista, S.?J.; Batley, J.?R.; Battaglia, M.; Bauce, M.; Bauer, F.; Bawa, H.?S.; Beacham, J.?B.; Beattie, M.?D.; Beau, T.; Beauchemin, P.?H.; Beccherle, R.; Bechtle, P.; Beck, H.?P.; Becker, K.; Becker, M.; Becker, S.; Beckingham, M.; Becot, C.; Beddall, A.?J.; Beddall, A.; Bednyakov, V.?A.; Bee, C.?P.; Beemster, L.?J.; Beermann, T.?A.; Begel, M.; Behr, J.?K.; Belanger-Champagne, C.; Bell, P.?J.; Bell, W.?H.; Bella, G.; Bellagamba, L.; Bellerive, A.; Bellomo, M.; Belotskiy, K.; Beltramello, O.; Benary, O.; Benchekroun, D.; Bender, M.; Bendtz, K.; Benekos, N.; Benhammou, Y.; Benhar Noccioli, E.; Benitez Garcia, J.?A.; Benjamin, D.?P.; Bensinger, J.?R.; Bentvelsen, S.; Beresford, L.; Beretta, M.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Berghaus, F.; Beringer, J.; Bernard, C.; Bernard, N.?R.; Bernius, C.; Bernlochner, F.?U.; Berry, T.; Berta, P.; Bertella, C.; Bertoli, G.; Bertolucci, F.; Bertsche, C.; Bertsche, D.; Besana, M.?I.; Besjes, G.?J.; Bessidskaia Bylund, O.; Bessner, M.; Besson, N.; Betancourt, C.; Bethke, S.; Bevan, A.?J.; Bhimji, W.; Bianchi, R.?M.; Bianchini, L.; Bianco, M.; Biebel, O.; Bieniek, S.?P.; Biglietti, M.; Bilbao De Mendizabal, J.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Black, C.?W.; Black, J.?E.; Black, K.?M.; Blackburn, D.; Blair, R.?E.; Blanchard, J.-B.; Blanco, J.?E.; Blazek, T.; Bloch, I.; Blocker, C.; Blum, W.; Blumenschein, U.; Bobbink, G.?J.; Bobrovnikov, V.?S.; Bocchetta, S.?S.; Bocci, A.; Bock, C.; Boehler, M.; Bogaerts, J.?A.; Bogdanchikov, A.?G.; Bohm, C.; Boisvert, V.; Bold, T.; Boldea, V.; Boldyrev, A.?S.; Bomben, M.; Bona, M.; Boonekamp, M.; Borisov, A.; Borissov, G.; Borroni, S.; Bortfeldt, J.; Bortolotto, V.; Bos, K.; Boscherini, D.; Bosman, M.; Boudreau, J.; Bouffard, J.; Bouhova-Thacker, E.?V.; Boumediene, D.; Bourdarios, C.; Bousson, N.; Boveia, A.; Boyd, J.; Boyko, I.?R.; Bozic, I.; Bracinik, J.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J.?E.; Braun, H.?M.; Brazzale, S.?F.; Brendlinger, K.; Brennan, A.?J.; Brenner, L.; Brenner, R.; Bressler, S.; Bristow, K.; Bristow, T.?M.; Britton, D.; Britzger, D.; Brochu, F.?M.; Brock, I.; Brock, R.; Bronner, J.; Brooijmans, G.; Brooks, T.; Brooks, W.?K.; Brosamer, J.; Brost, E.; Brown, J.

    2015-06-01

    A search has been performed for pair production of heavy vectorlike down-type (B) quarks. The analysis explores the lepton-plus-jets final state, characterized by events with one isolated charged lepton (electron or muon), significant missing transverse momentum, and multiple jets. One or more jets are required to be tagged as arising from b quarks, and at least one pair of jets must be tagged as arising from the hadronic decay of an electroweak boson. The analysis uses the full data sample of pp collisions recorded in 2012 by the ATLAS detector at the LHC, operating at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3??fb?¹. No significant excess of events is observed above the expected background. Limits are set on vectorlike B production, as a function of the B branching ratios, assuming the allowable decay modes are B ? Wt/Zb/Hb. In the chiral limit with a branching ratio of 100% for the decay B ? Wt, the observed (expected) 95% C.L. lower limit on the vectorlike B mass is 810 GeV (760 GeV). In the case where the vectorlike B quark has branching ratio values corresponding to those of an SU(2) singlet state, the observed (expected) 95% C.L. lower limit on the vectorlike B mass is 640 GeV (505 GeV). The same analysis, when used to investigate pair production of a colored, charge 5/3 exotic fermion T5/3, with subsequent decay T5/3 ? Wt, sets an observed (expected) 95% C.L. lower limit on the T5/3 mass of 840 GeV (780 GeV).

  6. Survey of lepton number violation via effective operators

    SciTech Connect (OSTI)

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

    2008-01-01

    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.

  7. Leptonic B Decays at BaBar

    SciTech Connect (OSTI)

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

    2011-09-13

    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.

  8. Leptonic B Decays at BaBar

    SciTech Connect (OSTI)

    Baracchini, Elisabetta; /Rome U. /INFN, Rome

    2011-11-10

    We 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 paid in order to perform a model independent analysis. A B-Factory provides an unique environment 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.

  9. Leptonic dark matter annihilation in the evolving universe: constraints and implications

    E-Print Network [OSTI]

    Yuan, Qiang; Bi, Xiaojun; Chen, Xuelei; Zhang, Xinmin

    2009-01-01

    The cosmic electron and positron excesses have been explained as possible dark matter (DM) annihilation products. In this work we investigate the possible effects of such kind of DM annihilation scenario during the evolution history of the Universe. We first calculate the extragalactic $\\gamma$-ray background (EGRB) produced through electrons/positrons inverse Compton scattering with the cosmic microwave background and the final state radiation. %by adopting a generic structure formation scenario. The DM halo profile and the minimal halo mass, which are not yet well determined from the current N-body simulations, are constrained by the EGRET data of EGRB. The preliminary EGRB data from the Fermi satellite are expected to set much stronger constraints. Then we discuss the impact of such leptonic DM model on cosmic evolution, such as the reionization and heating of intergalactic medium, neutral hydrogen 21 cm signal and suppression on structure formation. In some cases the 21 cm signal could be altered signific...

  10. Measurement of R = B(t?Wb)/B(t?Wq) in top-quark-pair decays using lepton+jets events and the full CDF run II dataset

    E-Print Network [OSTI]

    Gomez-Ceballos, Guillelmo

    We present a measurement of the ratio of the top-quark branching fractions R=B(t?Wb)/ B(t?Wq), where q represents quarks of type b, s, or d, in the final state with a lepton and hadronic jets. The measurement uses ?s=1.96??TeV ...

  11. Implications of the Diboson Excess for Neutrinoless Double Beta Decay and Lepton Flavor Violation in TeV Scale Left Right Symmetric Model

    E-Print Network [OSTI]

    Awasthi, Ram Lal; Mitra, Manimala

    2015-01-01

    Inspired by the recent diboson excess observed at the LHC and possible interpretation within a TeV-scale Left-Right symmetric framework, we explore its implications for low-energy experiments searching for lepton number and flavor violation. Assuming a simple Type-II seesaw mechanism for neutrino masses, we show that for the right-handed (RH) gauge boson mass and coupling values required to explain the LHC anomalies, the RH contribution to the lepton number violating process of neutrinoless double beta decay ($0\

  12. Calculation of two-centre two-electron integrals over Slater-type orbitals revisited. II. Neumann expansion of the exchange integrals

    E-Print Network [OSTI]

    Micha? Lesiuk; Robert Moszynski

    2015-01-08

    In this paper we consider calculation of two-centre exchange integrals over Slater-type orbitals (STOs). We apply the Neumann expansion of the Coulomb interaction potential and consider calculation of all basic quantities which appear in the resulting expression. Analytical closed-form equations for all auxiliary quantities have already been known but they suffer from large digital erosion when some of the parameters are large or small. We derive two differential equations which are obeyed by the most di?cult basic integrals. Taking them as a starting point, useful series expansions for small parameter values or asymptotic expansions for large parameter values are systematically derived. The resulting novel expansions replace the corresponding analytical expressions when the latter introduce significant cancellations. Additionally, we reconsider numerical integration of some necessary quantities and present a new way to calculate the integrand with a controlled precision. All proposed methods are combined to lead to a general, stable algorithm. We perform extensive numerical tests of the introduced expressions to verify their validity and usefulness. Advances reported here provide methodology to compute two-electron exchange integrals over STOs for a broad range of the nonlinear parameters and large angular momenta.

  13. Calculation of two-centre two-electron integrals over Slater-type orbitals revisited. III. Case study of the beryllium dimer

    E-Print Network [OSTI]

    Micha? Lesiuk; Micha? Przybytek; Monika Musia?; Bogumi? Jeziorski; Robert Moszynski

    2015-01-20

    In this paper we present results of ab-initio calculations for the beryllium dimer with basis set of Slater-type orbitals (STOs). Nonrelativistic interaction energy of the system is determined using the frozen-core full configuration interaction calculations combined with high-level coupled cluster correction for inner-shell effects. Newly developed STOs basis sets, ranging in quality from double to sextuple zeta, are used in these computations. Principles of their construction are discussed and several atomic benchmarks are presented. Relativistic effects of order ${\\alpha}^2$ are calculated perturbatively by using the Breit-Pauli Hamiltonian and are found to be significant. We also estimate the leading-order QED effects. Influence of the adiabatic correction is found to be negligible. Finally, the interaction energy of the beryllium dimer is determined to be 929.0$\\,\\pm\\,$1.9 $cm^{-1}$, in a very good agreement with the recent experimental value. The results presented here appear to be the most accurate ab-initio calculations for the beryllium dimer available in the literature up to date and probably also one of the most accurate calculations for molecular systems containing more than four electrons.

  14. Electron beam generation in Tevatron electron lenses

    SciTech Connect (OSTI)

    Kamerdzhiev, V.; Kuznetsov, G.; Shiltsev, V.; Solyak, N.; Tiunov, M.; /Novosibirsk, IYF

    2006-08-01

    New type of high perveance electron guns with convex cathode has been developed. Three guns described in this article are built to provide transverse electron current density distributions needed for Electron Lenses for beam-beam compensation in the Tevatron collider. The current distribution can be controlled either by the gun geometry or by voltage on a special control electrode located near cathode. We present the designs of the guns and report results of beam measurements on the test bench. Because of their high current density and low transverse temperature of electrons, electron guns of this type can be used in electron cooling and beam-beam compensation devices.

  15. Monte-Carlo simulation of lepton pair production in "p pbar --> l+l- + X" events at E_beam = 14 GeV

    E-Print Network [OSTI]

    A. N. Skachkova; N. B. Skachkov; G. D. Alexeev

    2011-03-08

    The lepton pair production in collisions of antiproton beam (E_beam = 14 GeV) with proton target is studied on the basis of event samples simulated with PYTHIA6 generator. Two types of quark level subprocesses are considered. The first one goes through the production of virtual photon which converts into lepton pair (q qbar --> gamma* --> l+l-) having a continuous energy spectrum of the final lepton pair invariant mass. The other subprocess proceeds through the J/Psi resonance production (p pbar --> J/Psi + X --> l+l- + X) with the following decay of J/Psi into a pair of leptons. The distributions of different kinematical variables which may be useful for the design of the muon system and the electromagnetic calorimeter of the detector of PANDA experiment at FAIR are presented. The analysis of these distribution shows the possibility to measure the proton structure function in a new kinematical region defined by the time-like values of the square of the momentum transferred 1 processes, are also discussed. The set of cuts which allows one to separate the signal events with lepton pairs from this kind of background events is proposed.

  16. A new bridge between leptonic CP violation and leptogenesis

    E-Print Network [OSTI]

    G. C. Branco; R. Gonzalez Felipe; F. R. Joaquim

    2006-09-28

    Flavor effects due to lepton interactions in the early Universe may have played an important role in the generation of the cosmological baryon asymmetry through leptogenesis. If the only source of high-energy CP violation comes from the left-handed leptonic sector, then it is possible to establish a bridge between flavored leptogenesis and low-energy leptonic CP violation. We explore this connection taking into account our present knowledge about low-energy neutrino parameters and the matter-antimatter asymmetry observed in the Universe. In this framework, we find that leptogenesis favors a hierarchical light neutrino mass spectrum, while for quasi-degenerate and inverted hierarchical neutrino masses there is a very narrow allowed window. The absolute neutrino mass scale turns out to be m < 0.1 eV.

  17. Electric Dipole Moments of Charged Leptons with Sterile Fermions

    E-Print Network [OSTI]

    Abada, Asmaa

    2015-01-01

    We address the impact of sterile fermions on charged lepton electric dipole moments. Any experimental signal of these observables calls for scenarios of physics beyond the Standard Model providing new sources of CP violation. In this work, we consider a minimal extension of the Standard Model via the addition of sterile fermions which mix with active neutrinos and we derive the corresponding analytical expressions for the electric dipole moments of charged leptons at two-loop order. Our study reveals that, in order to have a non-vanishing contribution in this framework, the minimal extension necessitates the addition of at least 2 sterile fermion states to the Standard Model field content. Our conclusion is that sterile neutrinos can give significant contributions to the charged lepton electric dipole moments, some of them lying within present and future experimental sensitivity if the masses of the non-degenerate sterile states are both above the electroweak scale. The Majorana nature of neutrinos is also im...

  18. Nonzero $?_{13}$ in $SO(3) \\rightarrow A_4$ lepton models

    E-Print Network [OSTI]

    Yuval Grossman; Wee Hao Ng

    2015-03-25

    The simplest neutrino mass models based on $A_4$ symmetry predict $\\theta_{13} = 0$ at tree level, a value that contradicts recent data. We study models that arise from the spontaneous breaking of an $SO(3)$ symmetry to its $A_4$ subgroup, and find that such models can naturally accommodate a nonzero $\\theta_{13}$ at tree level. Standard Model charged leptons mix with additional heavy ones to generate a $\\theta_{13}$ that scales with the ratio of the $A_4$-breaking to $SO(3)$-breaking scales. A suitable choice of energy scales hence allows one to reproduce the correct lepton mixing angles. We also consider an alternative approach where we modify the alignment of flavons associated with the charged lepton masses, and find that the effects on $\\theta_{13}$ are enhanced by a factor that scales as $m_\\tau/m_\\mu$.

  19. Nuclear PDF for neutrino and charged lepton data

    E-Print Network [OSTI]

    K. Kovarik

    2010-12-13

    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.

  20. Leptonic Decays of the Charged B Meson

    SciTech Connect (OSTI)

    Corwin, Luke A.; /Ohio State U.; ,

    2010-06-11

    The authors present a search for the decay B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} ({ell} = {tau}, {mu}, or e) in (458.9 {+-} 5.1) x 10{sup 6} {Upsilon}(4S) decays recorded with the BABAR detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed exclusive semi-leptonic B decay (B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}X) is selected, and in the recoil a search for B{sup +} {yields} {ell}{sup +}{nu}{sub {ell}} signal is performed. The {tau} is identified in the following channels: {tau}{sup +} {yields} e{sup +}{nu}{sub e}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {mu}{sup +}{nu}{sub {mu}}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {pi}{sup +}{bar {nu}}{sub {tau}}, and {tau}{sup +} {yields} {pi}{sup +}{pi}{sup 0}{bar {nu}}{sub {tau}}. The analysis strategy and the statistical procedure is set up for branching fraction extraction or upper limit determination. They determine from the dataset a preliminary measurement of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = (1.8 {+-} 0.8 {+-} 0.1) x 10{sup -4}, which excludes zero at 2.4{sigma}, and f{sub B} = 255 {+-} 58 MeV. Combination with the hadronically tagged measurement yields {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = (1.8 {+-} 0.6) x 10{sup -4}. They also set preliminary limits on the branching fractions at {Beta}(B{sup +} {yields} e{sup +}{nu}{sub e}) < 7.7 x 10{sup -6} (90% C.L.), {Beta}(B{sup +} {yields} {mu}{sup +}{nu}{sub {mu}}) < 11 x 10{sup -6} (90% C.L.), and {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) < 3.2 x 10{sup -4} (90% C.L.).

  1. Ansatz of Leptonic Mixing: The Alliance of Bi-Maximal Mixing with a Single-Angle Rotation

    E-Print Network [OSTI]

    Siyeon, Kim

    2012-01-01

    We introduce an ansatz of the PMNS matrix that consists of specific types of transformations. Bi-maximal mixing is taken for the neutrino masses, while a single-angle rotation in the 1-2 block is taken for the charged lepton masses. Motivated by the implications of the recent results on neutrino oscillations, $\\theta_{23}$ in the first octant and non-zero $\\theta_{13}$ are predicted by the ansatz. Three physical mixing angles are expressed in terms of a single variable, the 1-2 angle of charged leptons, so that a simple relation among the angles has been obtained: $\\tan\\theta_{13}=\\sqrt{2}(\\sin\\theta_{23}-\\sin\\theta_{12})$. It follows that a model of the inverted hierarchy that can produce the given ansatz is proposed.

  2. Search for lepton-flavour-violating decays of the Higgs boson...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Search for lepton-flavour-violating decays of the Higgs boson Citation Details In-Document Search Title: Search for lepton-flavour-violating decays of the Higgs...

  3. Search for Low Mass Exotic leptonic or bosonic structures

    E-Print Network [OSTI]

    B. Tatischeff; E. Tomasi-Gustafsson

    2007-07-09

    Recently, several papers discussed the existence of a low mass leptonic structure. It was suggested that the $\\Sigma^{+}$ disintegration: $\\Sigma^{+}\\to$pP$^{0}$, P$^{0}\\to\\mu^{-}\\mu^{+}$ proceeds through an intermediate particle P$^{0}$ having a mass close to M$\\approx$~214.3 MeV. The present work intends to look at other available data, in order to observe the eventual existence of a small peak or shoulder, at a mass close to M=214.3 MeV, which can strengthen the existence of a state produced by two leptons of opposite electric charge.

  4. Leptons and Quarks from a Discrete Flavor Symmetry

    E-Print Network [OSTI]

    Y. H. Ahn

    2013-03-20

    We propose a new model of leptons and quarks based on the discrete flavor symmetry $T'$, the double covering of $A_4$, in which the hierarchies of charged fermion masses and the mildness of neutrino masses are responsible for Higgs scalars. After spontaneous breaking of flavor symmetry, with the constraint of renormalizability in the Lagrangian, the leptons have $m_{e}=0$ and the quarks have the Cabibbo-Kobayashi-Maskawa (CKM) mixing angles $\\theta^{q}_{12}=13^{\\circ}, \\theta^{q}_{23}=0^{\\circ}$ and $\\theta^{q}_{13}=0^{\\circ}$. Thus, certain effective dimension-5 operators are introduced, which induce $m_{e}\

  5. A Search for Neutrinoless Tau Decays to Three Leptons

    SciTech Connect (OSTI)

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

    2008-09-24

    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}.

  6. Neutrinoless Double Beta Decay and Lepton Flavor Violation

    E-Print Network [OSTI]

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

    2004-06-17

    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.

  7. Bounds on R-parity violating supersymmetric couplings from leptonic and semileptonic meson decays

    SciTech Connect (OSTI)

    Dreiner, H. K.; Kraemer, M.; O'Leary, Ben [Physikalisches Institut der Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany); Institut fuer Theoretische Physik E, RWTH Aachen, 52056 Aachen (Germany); S.U.P.A., School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, Scotland (United Kingdom) and Institut fuer Theoretische Physik E, RWTH Aachen, 52056 Aachen (Germany)

    2007-06-01

    We present a comprehensive update of the bounds on R-parity violating supersymmetric couplings from lepton-flavor- and lepton-number-violating decay processes. We consider {tau} and {mu} decays as well as leptonic and semileptonic decays of mesons. We present several new bounds resulting from {tau}, {eta}, and kaon decays and correct some results in the literature concerning B meson decays.

  8. arXiv:0711.2528v2[astro-ph]23Jan2008 Production of Neutrinos and Secondary Electrons in Cosmic

    E-Print Network [OSTI]

    secondary particles with leptons as the final decay products. For the cosmic rays, protons and helium nucleiarXiv:0711.2528v2[astro-ph]23Jan2008 Production of Neutrinos and Secondary Electrons in Cosmic) 1 #12;Abstract We study the individual contribution to secondary lepton production in hadronic

  9. Leptonic Dirac CP Violation Predictions from Residual Discrete Symmetries

    E-Print Network [OSTI]

    Girardi, I; Stuart, Alexander J; Titov, A V

    2015-01-01

    Assuming that the observed pattern of 3-neutrino mixing is related to the existence of a (lepton) flavour symmetry, corresponding to a non-Abelian discrete symmetry group $G_f$, and that $G_f$ is broken to specific residual symmetries $G_e$ and $G_\

  10. Leptonic Dirac CP Violation Predictions from Residual Discrete Symmetries

    E-Print Network [OSTI]

    I. Girardi; S. T. Petcov; Alexander J. Stuart; A. V. Titov

    2015-09-08

    Assuming that the observed pattern of 3-neutrino mixing is related to the existence of a (lepton) flavour symmetry, corresponding to a non-Abelian discrete symmetry group $G_f$, and that $G_f$ is broken to specific residual symmetries $G_e$ and $G_\

  11. Hadronic decays of the tau lepton: Theoretical outlook

    E-Print Network [OSTI]

    J. Portoles

    2007-02-18

    The structure of the form factors stemmed from the hadronization of QCD currents in the energy region of the resonances can be explored through the analyses of exclusive hadronic decays of the tau lepton. I give a short review on the later theoretical progress achieved in the description of experimental data.

  12. Weak interactions of quarks and leptons: experimental status

    SciTech Connect (OSTI)

    Wojcicki, S.

    1984-09-01

    The present experimental status of weak interactions is discussed with emphasis on the problems and questions and on the possible lines of future investigations. Major topics include; (1) the quark mixing matrix, (2) CP violation, (3) rare decays, (4) the lepton sector, and (5) right handed currents. 118 references. (WHK)

  13. Partial Quark-Lepton Universality and Neutrino CP Violation

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

    Liao, Jiajun; Marfatia, D.; Whisnant, K.

    2015-01-01

    We study a model with partial quark-lepton universality that can naturally arise in grand unified theories. We find that constraints on the model can be reduced to a single condition on the Dirac CP phase ? in the neutrino sector. Using our current knowledge of the CKM and PMNS mixing matrices, we predict - 32 . 4 ° ? ? ? 32 . 0 ° at 2 ? .

  14. Lepton flavour violating processes at the International Linear Collider

    E-Print Network [OSTI]

    P. M. Ferreira; R. B. Guedes; R. Santos

    2007-02-13

    We study the effects of dimension six effective operators on the flavour violating production and decay of leptons at the International Linear Collider. Analytic expressions for the cross sections, decay widths and asymmetries of all flavour changing processes will be presented, as well as an analysis of the feasibility of their observation at the ILC.

  15. Measurement of charm production cross-section and leptons from its semileptonic decay at RHIC

    E-Print Network [OSTI]

    Yifei Zhang

    2008-09-09

    In this thesis, we present the measurements of $D^{0}\\to K\\pi$ at low $p_T$ ($p_T\\leq2$ GeV/$c$) and non-photonic electron spectra ($0.9\\leq p_T\\leq5$ GeV/$c$) from $D^0$ semi-leptonic decay. In addition, we use a newly proposed technique to identify muons from charm decays at low $p_T$. The combination of all these three measurements stringently constrains the total charm production cross-section at mid-rapidity at RHIC. They also allow the extraction of the charmed hadron spectral shape and a study of possible charm radial flow in Au+Au collisions.

  16. Controlling Graphene's Electronic Structure

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

    was reopened by the excess of electron charge-carriers on the graphene's surface layer. Progressive potassium deposition further enhanced the n-type doping. These results...

  17. 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)

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

    2008-05-01

    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.

  18. Search for a heavy gauge boson decaying to a charged lepton and a neutrino in 1 fb[superscript ?1] of pp collisions at ?s = 7 TeV using the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector at the LHC is used to search for high-mass states, such as heavy charged gauge bosons (W?), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of ...

  19. Bremsstrahlung Energy Losses for Cosmic Ray Electrons and Positrons

    E-Print Network [OSTI]

    Widom, A; Srivastava, R

    2015-01-01

    Recently cosmic ray electrons and positrons, i.e. cosmic ray charged leptons, have been observed. To understand the distances from our solar system to the sources of such lepton cosmic rays, it is important to understand energy losses from cosmic electrodynamic fields. Energy losses for ultra-relativistic electrons and/or positrons due to classical electrodynamic bremsstrahlung are computed. The energy losses considered are (i) due to Thompson scattering from fluctuating electromagnetic fields in the background cosmic thermal black body radiation and (ii) due to the synchrotron radiation losses from quasi-static domains of cosmic magnetic fields. For distances to sources of galactic length proportions, the lepton cosmic ray energy must be lass than about a TeV.

  20. Bremsstrahlung Energy Losses for Cosmic Ray Electrons and Positrons

    E-Print Network [OSTI]

    A. Widom; J. Swain; R. Srivastava

    2015-09-24

    Recently cosmic ray electrons and positrons, i.e. cosmic ray charged leptons, have been observed. To understand the distances from our solar system to the sources of such lepton cosmic rays, it is important to understand energy losses from cosmic electrodynamic fields. Energy losses for ultra-relativistic electrons and/or positrons due to classical electrodynamic bremsstrahlung are computed. The energy losses considered are (i) due to Thompson scattering from fluctuating electromagnetic fields in the background cosmic thermal black body radiation and (ii) due to the synchrotron radiation losses from quasi-static domains of cosmic magnetic fields. For distances to sources of galactic length proportions, the lepton cosmic ray energy must be lass than about a TeV.

  1. Lepton Mixing Predictions from (Generalised) CP and Discrete Flavour Symmetry

    E-Print Network [OSTI]

    Thomas Neder

    2015-03-31

    An important class of flavour groups, that are subgroups of $U(3)$ and that predict experimentally viable lepton mixing parameters including Majorana phases, is the $\\Delta(6n^2)$ series. The most well-known member is $\\Delta(24)=S_4$. I present results of several extensive studies of lepton mixing predictions obtained in models with a $\\Delta(6n^2)$ flavour group that preserve either the full residual $Z_2\\times Z_2$ or a $Z_2$ subgroup for neutrinos and can include a generalised CP symmetry. Predictions include mixing angles and Dirac CP phase generally; and if invariance under a generalised CP symmetry is included, also Majorana phases. For this, the interplay of flavour group and generalised CP symmetry has to be studied carefully.

  2. Search for Charged Lepton Violation in Narrow Upsilon Decays

    SciTech Connect (OSTI)

    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, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /LBL, Berkeley /UC, Berkeley; Hawkes, C.M.; /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. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2011-08-19

    Charged lepton flavor violating processes are unobservable in the standard model, but they are predicted to be enhanced in several extensions to the standard model, including supersymmetry and models with leptoquarks or compositeness. We present a search for such processes in a sample of 99 x 10{sup 6} {Upsilon}(2S) decays and 117 x 10{sup 6} {Upsilon}(3S) decays collected with the BABAR detector. We place upper limits on the branching fractions {Beta}({Upsilon}(nS) {yields} e{sup {+-}}{tau}{sup {-+}}) and {Beta}({Upsilon}(nS) {yields} {mu}{sup {+-}}{tau}{sup {-+}}) (n = 2, 3) at the 10{sup -6} level and use these results to place lower limits of order 1 TeV on the mass scale of charged lepton flavor violating effective operators.

  3. Lepton Number Violation within the Conformal Inverse Seesaw

    E-Print Network [OSTI]

    Humbert, Pascal; Patra, Sudhanwa; Smirnov, Juri

    2015-01-01

    We present a novel framework within the conformal inverse seesaw scheme allowing large lepton number violation while the neutrino mass formula is still governed by the low-scale inverse seesaw mechanism. This model includes new contributions to rare low-energy lepton number violating processes like neutrinoless double beta decay. We find that the lifetime for this rare process due to heavy sterile neutrinos can saturate current experimental limits. The characteristic collider signature of the present conformal inverse seesaw scheme includes, same-sign dilepton plus two jets and same-sign dilepton plus four jets. Finally, we comment on the testability of the model at the Large Hadron Collider since there are new scalars, new fermions and an extra neutral gauge boson with masses around few 100 GeV to few TeV.

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

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

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

    2012-06-26

    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 inmore »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.« less

  5. Statistical Understanding of Quark and Lepton Masses in Gaussian Landscapes

    E-Print Network [OSTI]

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

    2007-08-10

    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.

  6. Future Possibilities for Lepton-Hadron Collider Physics and Detectors

    E-Print Network [OSTI]

    Fleming, G; Lammers, S; Magill, S

    2001-01-01

    We have considered the physics opportunities of future lepton-hadron colliders and how these opportunities might be realized in a possible polarized eRHIC facility and an e-p collider as part of a staged or final version VLHC. We evaluated the physics priorities based on experience at HERA and, using simulated data for e-p collisions with sqrt(s) > 1 TeV, showed how detector designs would be impacted by the physics.

  7. Future Possibilities for Lepton-Hadron Collider Physics and Detectors

    E-Print Network [OSTI]

    G. Fleming; E. Kinney; S. Lammers; S. Magill

    2002-01-29

    We have considered the physics opportunities of future lepton-hadron colliders and how these opportunities might be realized in a possible polarized eRHIC facility and an e-p collider as part of a staged or final version VLHC. We evaluated the physics priorities based on experience at HERA and, using simulated data for e-p collisions with sqrt(s) > 1 TeV, showed how detector designs would be impacted by the physics.

  8. Electroweak Penguin and Leptonic Decays at BaBar

    SciTech Connect (OSTI)

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

    2005-08-26

    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}}.

  9. Clues for flavor from rare lepton and quark decays

    E-Print Network [OSTI]

    Ivo de Medeiros Varzielas; Gudrun Hiller

    2015-06-08

    Flavor symmetries successfully explain lepton and quark masses and mixings yet it is usually hard to distinguish different models that predict the same mixing angles. Further experimental input could be available, if the agents of flavor breaking are sufficiently low in mass and detectable or if new physics with non-trivial flavor charges is sufficiently low in mass and detectable. The recent hint for lepton-nonuniversality in the ratio of branching fractions $B \\to K \\mu \\mu$ over $B \\to K e e$, $R_K$, suggests the latter, at least for indirect detection via rare decays. We demonstrate the discriminating power of the rare decay data on flavor model building taking into account viable leptonic mixings and show how correlations with other observables exist in leptoquark models. We give expectations for branching ratios $B \\to K \\ell \\ell^\\prime, B_{(s)} \\to \\ell \\ell^\\prime$ and $\\ell \\to \\ell^\\prime \\gamma$, and Higgs decays $h \\to \\ell \\ell^\\prime$.

  10. Electron Beam Lithography

    E-Print Network [OSTI]

    Sandini, Giulio

    Electron Beam Lithography Marco Salerno #12;Outline · general lithographic concepts · EBL www.cnf.cornell.edu/SPIEBook/SPIE1.HTM #12;Typical Electron Beam Column Zeiss GeminiTM column Types of Electron Beam Columns · no e- cross over no Boersch-effect (additional energy spread) · beam booster

  11. Electronic structure and thermoelectric properties of p-type Ag-doped Mg?Sn and Mg?Sn{sub 1-x}Si{sub x} (x=0.05, 0.1)

    SciTech Connect (OSTI)

    Kim, Sunphil; Jin, Hyungyu [Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Wiendlocha, Bartlomiej, E-mail: wiendlocha@fis.agh.edu.pl [Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Krakow (Poland); Tobola, Janusz [AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Krakow (Poland); Heremans, Joseph P., E-mail: heremans.1@osu.edu [Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States)

    2014-10-21

    An experimental and theoretical study of p-type Ag-doped Mg?Sn and Mg?Sn{sub 1-x}Si{sub x} (x=0.05, 0.1) is presented. Band structure calculations show that behavior of Ag in Mg?Sn depends on the site it occupies. Based on Bloch spectral functions and density of states calculations, we show that if Ag substitutes for Sn, it is likely to form a resonant level; if it substitutes for Mg, a rigid-band-like behavior is observed. In both cases, the doped system should exhibit p-type conductivity. Experimentally, thermoelectric, thermomagnetic, and galvanomagnetic properties are investigated of p-type Mg?Sn{sub 1–x}Si{sub x} (x=0, 0.05, 0.1) samples synthesized by a co-melting method in sealed crucibles. Ag effectively dopes the samples p-type, and thermoelectric power factors in excess of 20?W cm?¹K?² are observed in optimally doped samples. From the measured Seebeck coefficient, Nernst coefficient, and mobility, we find that the combination of acoustic phonon scattering, optical phonon scattering and defect scattering results in an energy-independent scattering rate. No resonant-like increase in thermopower is observed, which correlates well with electronic structure calculations assuming the location of Ag on Mg site.

  12. The Potential of the Linac-Ring Type Colliders for Particle and Nuclear Physics

    E-Print Network [OSTI]

    A. K. Ciftci; E. Recepoglu; S. Sultansoy; O. Yavas; M. Yilmaz

    2003-10-02

    Linac-ring type colliders will open new windows for both energy frontier and particle factories. Concerning the first direction, these machines seem to be a sole way to TeV scale in lepton-hadron collisison at constituent level. An essential advantage of the linac-ring type lepton-hadron colliders is the possibility of the construction of gamma-p, gamma-A and FELgamma-A colliders based on them. Today, eRHIC, THERA (TESLA on HERA)and Linac*LHC can be considered as realistic candidates for future lepton-hadron and photon hadron colliders. When it comes to factories, one can reach essentially higher luminosities comparing to standard ring-ring type machines. For example, L=10^34 cm^-2 s^-1 can be achieved for phi and charm-tau factories. In this presentation we briefly discuss the parameters and physics search potential of the linac-ring type machines.

  13. Constraints on Majorana dark matter from a fourth lepton family

    SciTech Connect (OSTI)

    Hapola, Tuomas [Institute for Particle Physics Phenomenology, Durham University, South Road, Durham DH1 3LE (United Kingdom); Järvinen, Matti [Crete Center for Theoretical Physics, University of Crete, 71003 Heraklion (Greece); Kouvaris, Chris; Panci, Paolo; Virkajärvi, Jussi, E-mail: t.a.hapola@durham.ac.uk, E-mail: mjarvine@physics.uoc.gr, E-mail: kouvaris@cp3.dias.sdu.dk, E-mail: panci@cp3-origins.net, E-mail: virkajarvi@cp3-origins.net [CP "3-Origins and DIAS, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)

    2014-02-01

    We study the possibility of dark matter in the form of heavy neutrinos from a fourth lepton family with helicity suppressed couplings such that dark matter is produced thermally via annihilations in the early Universe. We present all possible constraints for this scenario coming from LHC and collider physics, underground direct detectors, neutrino telescopes, and indirect astrophysical searches. Although we embed the WIMP candidate within a model of composite dynamics, the majority of our results are model independent and applicable to all models where heavy neutrinos with suppressed couplings account for the dark matter abundance.

  14. On the Potential of Leptonic Minimal Flavour Violation

    E-Print Network [OSTI]

    R. Alonso; M. B. Gavela; D. Hernández; L. Merlo

    2012-07-29

    Minimal Flavour Violation can be realized in several ways in the lepton sector due to the possibility of Majorana neutrino mass terms. We derive the scalar potential for the fields whose background values are the Yukawa couplings, for the simplest See-Saw model with just two right-handed neutrinos, and explore its minima. The Majorana character plays a distinctive role: the minimum of the potential allows for large mixing angles -in contrast to the simplest quark case- and predicts a maximal Majorana phase. This points in turn to a strong correlation between neutrino mass hierarchy and mixing pattern.

  15. Muon g-2 Anomaly and Dark Leptonic Gauge Boson

    SciTech Connect (OSTI)

    Lee, Hye-Sung [W& M

    2014-11-01

    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.

  16. Lepton-pair production in nuclear collisions - past, present, future

    E-Print Network [OSTI]

    H. J. Specht

    2007-10-29

    The key results on lepton-pair production in ultra-relativistic nuclear collisions are shortly reviewed, starting at the roots of pp collisions in the seventies, and ending at the perspectives of the colliders RHIC and LHC. The presence is dominated by the recent precision results from NA60 at the CERN SPS, culminating in the first measurement of the in-medium rho spectral function and the transverse flow of the associated thermal radiation. The seeming cut-off of the flow above the rho may well be the first direct hint for thermal radiation of partonic origin in nuclear collisions. The major milestones in the theoretical developments are also covered.

  17. Measurement of the Top Quark Mass in the Lepton+Jets Channel Using the Lepton Transverse Momentum

    SciTech Connect (OSTI)

    Aaltonen, T.; Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.; /Purdue U. /Waseda U. /Dubna, JINR

    2011-01-01

    This letter reports a measurement of the top quark mass, M{sub top}, in data from p{bar p} collisions at {radical}s = 1.96 TeV corresponding to 2.7 fb{sup -1} of integrated luminosity at the Fermilab Tevatron using the CDF II detector. Events with the lepton+jets topology are selected. An unbinned likelihood is constructed based on the dependence of the lepton transverse momentum, P{sub T}, on M{sub top}. A maximum likelihood fit to the data yields a measured mass M{sub top} = 176.9 {+-} 8.0{sub stat} {+-} 2.7{sub syst} GeV/c{sup 2}. In this measurement, the contribution by the jet energy scale uncertainty to the systematic error is negligible. The result provides an important consistency test for other M{sub top} measurements where explicit use of the jet energy is made for deriving the top quark mass.

  18. Calculation of two-centre two-electron integrals over Slater-type orbitals revisited. III. Case study of the beryllium dimer

    E-Print Network [OSTI]

    Lesiuk, Micha?; Musia?, Monika; Jeziorski, Bogumi?; Moszynski, Robert

    2014-01-01

    In this paper we present results of ab-initio calculations for the beryllium dimer with basis set of Slater-type orbitals (STOs). Nonrelativistic interaction energy of the system is determined using the frozen-core full configuration interaction calculations combined with high-level coupled cluster correction for inner-shell effects. Newly developed STOs basis sets, ranging in quality from double to sextuple zeta, are used in these computations. Principles of their construction are discussed and several atomic benchmarks are presented. Relativistic effects of order ${\\alpha}^2$ are calculated perturbatively by using the Breit-Pauli Hamiltonian and are found to be significant. We also estimate the leading-order QED effects. Influence of the adiabatic correction is found to be negligible. Finally, the interaction energy of the beryllium dimer is determined to be 929.0$\\,\\pm\\,$1.9 $cm^{-1}$, in a very good agreement with the recent experimental value. The results presented here appear to be the most accurate ab-...

  19. Neutrino properties deduced from the study of lepton number violating processes at low and high energies

    SciTech Connect (OSTI)

    Stoica, Sabin [Horia Hulubei Foundation, P.O. Box MG-12, 077125 Magurele-Bucharest (Romania) and Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O. Box MG-6, Magurele-Bucharest 077125 (Romania)

    2012-11-20

    There is nowadays a significant progress in understanding the neutrino properties. The results of the neutrino oscillation experiments have convincingly showed that neutrinos have mass and oscillate, in contradiction with the Standard Model (SM) assumptions, and these are the first evidences of beyond SM physics. However, fundamental properties of the neutrinos like their absolute mass, their character (are they Dirac or Majorana particles?), their mass hierarchy, the number of neutrino flavors, etc., still remain unknown. In this context there is an increased interest in the study of the lepton number violating (LNV) processes, since they could complete our understanding on the neutrino properties. Since recently, the neutrinoless double beta decay was considered the only process able to distinguish between Dirac or Majorana neutrinos and to give a hint on the absolute mass of the electron neutrino. At present, the increased luminosity of the LHC experiments makes feasible the search of LNV processes at high energy as well. In this lecture I will make a brief review on our present knowledge of the neutrino properties, on the present status of the double-beta decay studies and on the first attempts to search LNV processes at LHC.

  20. Azimuthal Correlations between Non-Photonic Electrons and Charged Hadrons in p+p Collisions from STAR

    E-Print Network [OSTI]

    Xiaoyan Lin

    2006-09-21

    We present the preliminary measurement of azimuthal correlations between non-photonic electrons and charged hadrons in p+p collisions at $\\sqrt{s_{NN}} = 200$ GeV from STAR. The results are compared to PYTHIA simulations to estimate the relative contributions of $D$ and $B$ meson semi-leptonic decays to the non-photonic electrons.

  1. Search for High-Mass States with One Lepton Plus Missing Transverse Momentum in Proton-Proton Collisions at $\\sqrt{s} with the ATLAS Detector

    SciTech Connect (OSTI)

    Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdelalim, Ahmed Ali; Abdesselam, Abdelouahab; Abdinov, Ovsat; Abi, Babak; Abolins, Maris; Abramowicz, Halina; Abreu, Henso; Acerbi, Emilio; Acharya, Bobby Samir; Adams, David; Addy, Tetteh; Adelman, Jahred; Aderholz, Michael; Adomeit, Stefanie; Adragna, Paolo; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; /Freiburg U. /Oklahoma U. /Barcelona, IFAE /Geneva U. /Oxford U. /Baku, Inst. Phys. /Oklahoma State U. /Michigan State U. /Tel Aviv U. /Orsay, LAL /INFN, Milan /Milan U. /INFN, Udine /ICTP, Trieste /Brookhaven /Hampton U. /Yale U. /Heidelberg, Max Planck Inst. /Munich U. /Queen Mary, U. of London /Rutherford

    2012-06-20

    The ATLAS detector is used to search for high-mass states, such as heavy charged gauge bosons (W{prime},W*), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of ppcollisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 36 pb{sup -1}. No excess beyond standard model expectations is observed. A W{prime} with sequential standard model couplings is excluded at 95% confidence level for masses below 1.49 TeV, and a W* (charged chiral boson) for masses below 1.35 TeV.

  2. The Ds and D+ Leptonic Decay Constants from Lattice QCD

    E-Print Network [OSTI]

    A. Bazavov; C. Bernard; C. DeTar; E. D. Freeland; E. Gamiz; Steven Gottlieb; U. M. Heller; J. E. Hetrick; A. X. El-Khadra; A. S. Kronfeld; J. Laiho; L. Levkova; P. B. Mackenzie; M. B. Oktay; M. Di Pierro; J. N. Simone; R. Sugar; D. Toussaint; R. S. Van de Water

    2009-12-28

    We present the leptonic decay constants fDs and fD+ computed on the MILC collaboration's 2+1 flavor asqtad gauge ensembles. We use clover heavy quarks with the Fermilab interpretation and improved staggered light quarks. The simultaneous chiral and continuum extrapolation, which determines both decay constants, includes partially-quenched lattice results at lattice spacings a ~ 0:09, 0:12 and 0:15 fm. We have made several recent improvements in our analysis: a) we include terms in the fit describing leading order heavy-quark discretization effects, b) we have adopted a more precise input r1 value consistent with our other D and B meson studies, c) we have retuned the input bare charm masses based upon the new r1. Our preliminary results are fDs = 260 +/-10 MeV and fD+ = 217 +/-10 MeV.

  3. Form factors for semi-leptonic B decays

    E-Print Network [OSTI]

    Ran Zhou; Steven Gottlieb; Jon A. Bailey; Daping Du; Aida X. El-Khadra; R. D. Jain; Andreas S. Kronfeld; Ruth S. Van de Water; Yuzhi Liu; Yannick Meurice; for the Fermilab Lattice; MILC Collaborations

    2012-11-06

    We report on form factors for the B->K l^+ l^- semi-leptonic decay process. We use several lattice spacings from a=0.12 fm down to 0.06 fm and a variety of dynamical quark masses with 2+1 flavors of asqtad quarks provided by the MILC Collaboration. These ensembles allow good control of the chiral and continuum extrapolations. The b-quark is treated as a clover quark with the Fermilab interpretation. We update our results for f_\\parallel and f_\\perp, or, equivalently, f_+ and f_0. In addition, we present new results for the tensor form factor f_T. Model independent results are obtained based upon the z-expansion.

  4. Search for Pair Production of Scalar Top Quarks Decaying to a tau Lepton and a b Quark in ppbar Collisions at sqrt{s}=1.96 TeV

    SciTech Connect (OSTI)

    Brigliadori, L.; Zheng, Y.; Zucchelli, S.; /Taiwan, Inst. Phys. /Bologna U. /Argonne /Barcelona, IFAE /Baylor U., Math. Dept. /Bologna U. /Brandeis U. /UC, Davis /UCLA /UC, San Diego /UC, Santa Barbara /Cantabria U., Santander /Carnegie Mellon U.

    2008-02-01

    We 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. We assume each {tilde t}{sub 1} decays into a {tau} lepton and a b quark with a branching ratio {beta}, and that the final state contains 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 our final selection criteria, consistent with the expectation from standard model processes. We 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, we set a 95% confidence level limit m({tilde t}{sub 1}) > 153 GeV=c{sup 2} obtained using a next-to-leading order cross section. These limits are also fully applicable to the case of a pair produced third generation scalar leptoquark decaying into a {tau} lepton and a b quark.

  5. Search for the standard model Higgs boson in the decay channel $H$ to $Z Z$ to 4 leptons in $pp$ collisions at $\\sqrt{s}=7$ TeV

    SciTech Connect (OSTI)

    Chatrchyan, Serguei; et al.

    2012-03-01

    A search for a Higgs boson in the four-lepton decay channel H to ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range 110 < mH < 600 GeV. The analysis uses data corresponding to an integrated luminosity of 4.7 inverse femtobarns recorded by the CMS detector in pp collisions at sqrt(s) = 7 TeV from the LHC. Seventy-two events are observed with four-lepton invariant mass m[4 leptons] > 100 GeV (with thirteen below 160 GeV), while 67.1 +/- 6.0 (9.5 +/-1.3) events are expected from background. The four-lepton mass distribution is consistent with the expectation of standard model background production of ZZ pairs. Upper limits at 95% confidence level exclude the standard model Higgs boson in the ranges 134-158 GeV, 180-305 GeV, and 340 -465 GeV. Small excesses of events are observed around masses of 119, 126, and 320 GeV, making the observed limits weaker than expected in the absence of a signal.

  6. PDF Nuclear Corrections for Charged Lepton and Neutrino Deep Inelastic Scattering Processes

    E-Print Network [OSTI]

    I. Schienbein; J. Y. Yu; K. Kovarik; C. Keppel; J. G. Morfin; F. Olness; J. F. Owens

    2010-02-11

    We perform a \\chi^2-analysis of Nuclear Parton Distribution Functions (NPDFs) using neutral current charged-lepton Deeply Inelastic Scattering (DIS) and Drell-Yan data for several nuclear targets. The nuclear A dependence of the NPDFs is extracted in a next-to-leading order fit. We compare the nuclear corrections factors F2(Fe)/F2(D) for this 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.

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

    E-Print Network [OSTI]

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

    2015-01-01

    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.

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

    E-Print Network [OSTI]

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

    2015-09-11

    Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any preexisting baryon asymmetry of the Universe. In this article, 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 other than the standard light neutrino exchange 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.

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

    E-Print Network [OSTI]

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

    2015-03-16

    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.

  10. Lepton number asymmetry via inflaton decay in a modified radiative seesaw model

    E-Print Network [OSTI]

    Kashiwase, Shoichi

    2015-01-01

    We propose a non-thermal scenario for the generation of baryon number asymmetry in a radiative neutrino mass model which is modified to realize inflation at the early Universe. In this scenario, inflaton plays a crucial role in both generation of neutrino masses and lepton number asymmetry. Lepton number asymmetry is firstly generated in the dark matter sector through direct decay of inflaton. It is transferred to the lepton sector via the dark matter annihilation and then converted to the baryon number asymmetry due to the sphaleron interaction. All of the neutrino masses, the baryon number asymmetry and the dark matter are intimately connected to each other through the inflaton.

  11. Crystal and electronic structures of CaAl{sub 2}Si{sub 2}-type rare-earth copper zinc phosphides RECuZnP{sub 2} (RE=Pr, Nd, Gd-Tm, Lu)

    SciTech Connect (OSTI)

    Blanchard, Peter E.R.; Stoyko, Stanislav S.; Cavell, Ronald G. [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada); Mar, Arthur, E-mail: arthur.mar@ualberta.c [Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2 (Canada)

    2011-01-15

    The quaternary rare-earth phosphides RECuZnP{sub 2} (RE=Pr, Nd, Gd-Tm, Lu) have been prepared by reaction of the elements at 900 {sup o}C, completing this versatile series which forms for nearly all RE metals. They adopt the trigonal CaAl{sub 2}Si{sub 2}-type structure (Pearson symbol hP5, space group P3-bar m1, Z=1), as confirmed by single-crystal X-ray diffraction analysis on ErCuZnP{sub 2} and powder X-ray diffraction analysis on the remaining members. The Cu and Zn atoms are assumed to be disordered over the single transition-metal site. Band structure calculations on a hypothetically ordered YCuZnP{sub 2} model suggest a semimetal, with a zero band gap between the valence and conduction bands. This electronic structure is supported by XPS valence band spectra for RECuZnP{sub 2} (RE=Gd-Er), in which the intensity drops off smoothly at the Fermi edge. The absence of a band gap permits the electron count to deviate from the precise value of 16 e{sup -} per formula unit, as demonstrated by the formation of a solid solution in GdCu{sub x}Zn{sub 2-x}P{sub 2} (1.0{<=}x{<=}1.3), while still retaining the CaAl{sub 2}Si{sub 2}-type structure. Because the Cu 2p XPS spectra indicate that the Cu atoms are always monovalent, the substitution of Cu for Zn leads to a decrease in electron count and a lowering of the Fermi level in the valence band. The magnetic susceptibility of RECuZnP{sub 2} (RE=Gd-Er), which obeys the Curie-Weiss law, confirms the presence of trivalent RE atoms. -- Graphical abstract: The absence of a band gap in the semimetallic quaternary rare-earth phosphides RECuZnP{sub 2} permits the formation of a solid solution such as GdCu{sub x}Zn{sub 2-x}P{sub 2} through hole-doping of the valence band. Display Omitted

  12. Electron radiography

    DOE Patents [OSTI]

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  13. Search for new ?[superscript 0]-like particles produced in association with a ?-lepton pair

    E-Print Network [OSTI]

    Lees, J.?P.

    We report on a search in e[superscript +]e[superscript -] annihilations for new ?[superscript 0]-like particles produced in association with a ?-lepton pair. These objects, with a similar mass and similar decay modes to ...

  14. Precision measurement of the top quark mass in the lepton + jets...

    Office of Scientific and Technical Information (OSTI)

    Precision measurement of the top quark mass in the lepton + jets channel using a matrix element method with Quasi-Monte Carlo integration Citation Details In-Document Search...

  15. Search for production of vector-like quark pairs and of four top quarks in the lepton-plus-jets final state in pp collisions at ?s = 8 TeV with the ATLAS detector

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

    Aad, G.

    2015-08-20

    A search for pair production of vector-like quarks, both up-type (T) and down-type (B), as well as for four-top-quark production, is presented. The search is based on pp collisions at \\( \\sqrt{s}=8 \\) TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 20.3 fb–1. Data are analysed in the lepton-plus-jets final state, characterised by an isolated electron or muon with high transverse momentum, large missing transverse momentum and multiple jets. Dedicated analyses are performed targeting three cases: a T quark with significant branching ratio to a W bosonmore »and a b-quark \\( \\left(T\\overline{T}\\to Wb+\\mathrm{X}\\right) \\), and both a T quark and a B quark with significant branching ratio to a Higgs boson and a third-generation quark (\\( T\\overline{T}\\to Ht+X\\;\\mathrm{and}\\;B\\overline{B}\\to Hb+\\mathrm{X} \\) respectively). No significant excess of events above the Standard Model expectation is observed, and 95% CL lower limits are derived on the masses of the vector-like T and B quarks under several branching ratio hypotheses assuming contributions from T ? Wb, Zt, Ht and B ? Wt, Zb, Hb decays. The 95% CL observed lower limits on the T quark mass range between 715 GeV and 950 GeV for all possible values of the branching ratios into the three decay modes, and are the most stringent constraints to date. In addition, the most restrictive upper bounds on four-top-quark production are set in a number of new physics scenarios.« less

  16. Search for production of vector-like quark pairs and of four top quarks in the lepton-plus-jets final state in pp collisions at ?s = 8 TeV with the ATLAS detector

    SciTech Connect (OSTI)

    Aad, G.

    2015-08-20

    A search for pair production of vector-like quarks, both up-type (T) and down-type (B), as well as for four-top-quark production, is presented. The search is based on pp collisions at \\( \\sqrt{s}=8 \\) TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 20.3 fb–1. Data are analysed in the lepton-plus-jets final state, characterised by an isolated electron or muon with high transverse momentum, large missing transverse momentum and multiple jets. Dedicated analyses are performed targeting three cases: a T quark with significant branching ratio to a W boson and a b-quark \\( \\left(T\\overline{T}\\to Wb+\\mathrm{X}\\right) \\), and both a T quark and a B quark with significant branching ratio to a Higgs boson and a third-generation quark (\\( T\\overline{T}\\to Ht+X\\;\\mathrm{and}\\;B\\overline{B}\\to Hb+\\mathrm{X} \\) respectively). No significant excess of events above the Standard Model expectation is observed, and 95% CL lower limits are derived on the masses of the vector-like T and B quarks under several branching ratio hypotheses assuming contributions from T ? Wb, Zt, Ht and B ? Wt, Zb, Hb decays. The 95% CL observed lower limits on the T quark mass range between 715 GeV and 950 GeV for all possible values of the branching ratios into the three decay modes, and are the most stringent constraints to date. In addition, the most restrictive upper bounds on four-top-quark production are set in a number of new physics scenarios.

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

    E-Print Network [OSTI]

    C. Lazzeroni et al.

    2011-03-01

    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.

  18. Study of predominant hadronic modes of $?$-lepton using a Monte Carlo generator TAUOLA

    E-Print Network [OSTI]

    O. Shekhovtsova

    2015-08-22

    TAUOLA is a Monte Carlo generator dedicated to generating tau-lepton decays and it is used in the analysis of experimental data both at B-factories and LHC. TAUOLA is a long-term project that started in the 90's and has been under development up to now. In this note we discuss the status of the predominant hadronic tau-lepton decays into two ($Br \\simeq 25.52\\%$) and three pions ($Br \\simeq 18.67\\%$).

  19. Lepton Flavor Violation in Predictive SUSY-GUT Models

    SciTech Connect (OSTI)

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

    2008-02-01

    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.

  20. Kubo relations and radiative corrections for lepton number washout

    SciTech Connect (OSTI)

    Bödeker, Dietrich; Laine, M. E-mail: laine@itp.unibe.ch

    2014-05-01

    The rates for lepton number washout in extensions of the Standard Model containing right-handed neutrinos are key ingredients in scenarios for baryogenesis through leptogenesis. We relate these rates to real-time correlation functions at finite temperature, without making use of any particle approximations. The relations are valid to quadratic order in neutrino Yukawa couplings and to all orders in Standard Model couplings. They take into account all spectator processes, and apply both in the symmetric and in the Higgs phase of the electroweak theory. We use the relations to compute washout rates at next-to-leading order in g, where g denotes a Standard Model gauge or Yukawa coupling, both in the non-relativistic and in the relativistic regime. Even in the non-relativistic regime the parametrically dominant radiative corrections are only suppressed by a single power of g. In the non-relativistic regime radiative corrections increase the washout rate by a few percent at high temperatures, but they are of order unity around the weak scale and in the relativistic regime.

  1. Organic electronic devices with multiple solution-processed layers

    DOE Patents [OSTI]

    Forrest, Stephen R.; Lassiter, Brian E.; Zimmerman, Jeramy D.

    2015-08-04

    A method of fabricating a tandem organic photosensitive device involves depositing a first layer of an organic electron donor type material film by solution-processing of the organic electron donor type material dissolved in a first solvent; depositing a first layer of an organic electron acceptor type material over the first layer of the organic electron donor type material film by a dry deposition process; depositing a conductive layer over the interim stack by a dry deposition process; depositing a second layer of the organic electron donor type material over the conductive layer by solution-processing of the organic electron donor type material dissolved in a second solvent, wherein the organic electron acceptor type material and the conductive layer are insoluble in the second solvent; depositing a second layer of an organic electron acceptor type material over the second layer of the organic electron donor type material film by a dry deposition process, resulting in a stack.

  2. The double mass hierarchy pattern: simultaneously understanding quark and lepton mixing

    E-Print Network [OSTI]

    Wolfgang Gregor Hollik; Ulises Jesus Saldana Salazar

    2015-01-21

    The charged fermion masses of the three generations exhibit the two strong hierarchies m_3 >> m_2 >> m_1. We assume that also neutrino masses satisfy m_{nu 3} > m_{nu 2} > m_{nu 1} and derive the consequences of the hierarchical spectra on the fermionic mixing patterns. The quark and lepton mixing matrices are built in a general framework with their matrix elements expressed in terms of the four fermion mass ratios m_u/m_c, m_c/m_t, m_d/m_s, and m_s/m_b and m_e/m_mu, m_mu/m_tau, m_{nu 1}/m_{nu 2}, and m_{nu 2}/m_{nu 3}, for the quark and lepton sector, respectively. In this framework, we show that the resulting mixing matrices are consistent with data for both quarks and leptons, despite the large leptonic mixing angles. The minimal assumption we take is the one of hierarchical masses and minimal flavour symmetry breaking that strongly follows from phenomenology. No special structure of the mass matrices has to be assumed that cannot be motivated by this minimal assumption. This analysis allows us to predict the neutrino mass spectrum and set the mass of the lightest neutrino well below 0.01 eV. The method also gives the 1 sigma allowed ranges for the leptonic mixing matrix elements. Contrary to the common expectation, leptonic mixing angles are found to be determined solely by the four leptonic mass ratios without any relation to symmetry considerations as commonly used in flavor model building. Still, our formulae can be used to build up a flavor model that predicts the observed hierarchies in the masses---the mixing follows then from the procedure which is developed in this work.

  3. Measurement of the production and lepton charge asymmetry of W bosons in Pb+Pb collisions at ?sNN = 2.76 TeV with the ATLAS detector

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

    Aad, G.

    2015-01-22

    A measurement of W boson production in lead-lead collisions at ?sNN=2.76 TeV is presented. It is based on the analysis of data collected with the ATLAS detector at the LHC in 2011 corresponding to an integrated luminosity of 0.14 nb–1 and 0.15 nb–1 in the muon and electron decay channels, respectively. The differential production yields and lepton charge asymmetry are each measured as a function of the average number of participating nucleons (Npart) and absolute pseudorapidity of the charged lepton. The results are compared to predictions based on next-to-leading-order QCD calculations. As a result, these measurements are, in principle, sensitivemore »to possible nuclear modifications to the parton distribution functions and also provide information on scaling of W boson production in multi-nucleon systems.« less

  4. Measurement of the production and lepton charge asymmetry of $\\textit{W}$ bosons in Pb+Pb collisions at $\\sqrt{s_{\\mathrm{\\mathbf{NN}}}}=$ 2.76 TeV with the ATLAS detector

    E-Print Network [OSTI]

    ATLAS Collaboration

    2015-01-26

    A measurement of $\\textit{W}$ boson production in lead-lead collisions at $\\sqrt{s_{\\mathrm{NN}}}=$2.76 TeV is presented. It is based on the analysis of data collected with the ATLAS detector at the LHC in 2011 corresponding to an integrated luminosity of 0.14 $\\mathrm{nb}^{-1}$ and 0.15 $\\mathrm{nb}^{-1}$ in the muon and electron decay channels, respectively. The differential production yields and lepton charge asymmetry are each measured as a function of the average number of participating nucleons $$ and absolute pseudorapidity of the charged lepton. The results are compared to predictions based on next-to-leading-order QCD calculations. These measurements are, in principle, sensitive to possible nuclear modifications to the parton distribution functions and also provide information on scaling of $\\textit{W}$ boson production in multi-nucleon systems.

  5. Parametrization of lepton mixing matrix in terms of deviations from bi-maximal and tri-bimaximl mixing

    E-Print Network [OSTI]

    Chandan Duarah; K. Sashikanta Singh; N. Nimai Singh

    2015-03-26

    We parametrize lepton mixing matrix, known as PMNS matrix, in terms of three parameters which account deviations of three mixing angles from their bi-maximal or tri-bimaximal values. On the basis of this parametrization we can determine corresponding charged lepton mixing matrix in terms of those three parameters which can deviate bi-maximal or tri-bimaximal mixing. We find that the charged lepton mixing matrices which can deviate bi-maximal mixing matrix and tri-bimaximal mixing matrix exhibit similar structures. Numerical analysis shows that these charged lepton mixing matrices are close to CKM matrix of quark sector.

  6. Low scale seesaw, electron EDM and leptogenesis in a model with spontaneous CP violation

    SciTech Connect (OSTI)

    Chen, Mu-Chun; /Fermilab /UC, Irvine; Mahanthappa, K.T.; /Colorado U.

    2006-09-01

    Strong correlations between leptogenesis and low energy CP violating leptonic processes have been shown by us to exist fin the minimal left-right symmetric model with spontaneous CP violation. In this note, they investigate the implications of this model for the electric dipole moment of the electron. With an additional broken U(1){sub H} symmetry, the seesaw scale can be lowered to close to the electroweak scale. This additional symmetry also makes the connection between CP violation in quark sector to that in the lepton sector possible.

  7. PLZT film capacitors for power electronics and energy storage...

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

    PLZT film capacitors for power electronics and energy storage applications Title PLZT film capacitors for power electronics and energy storage applications Publication Type Journal...

  8. TESLA*HERA as Lepton (Photon)-Hadron Collider

    E-Print Network [OSTI]

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

    2000-04-11

    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.

  9. Exclusion of an Exotic Top Quark with -4/3 Electric Charge Using Soft Lepton Tagging

    SciTech Connect (OSTI)

    Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.; Apresyan, A.; /Purdue U. /Waseda U.

    2010-06-01

    We present a measurement of the electric charge of the top quark using p{bar p} collisions corresponding to an integrated luminosity of 2.7 fb{sup -1} at the CDF II detector. We reconstruct t{bar t} events in the lepton+jets final state and use kinematic information to determine which b-jet is associated with the leptonically- or hadronically-decaying t-quark. Soft lepton taggers are used to determine the b-jet flavor. Along with the charge of the W boson decay lepton, this information permits the reconstruction of the top quark's electric charge. Out of 45 reconstructed events with 2.4 {+-} 0.8 expected background events, 29 are reconstructed as tt with the standard model +2/3 charge, whereas 16 are reconstructed as t{bar t} with an exotic -4/3 charge. This is consistent with the standard model and excludes the exotic scenario at 95% confidence level. This is the strongest exclusion of the exotic charge scenario and the first to use soft leptons for this purpose.

  10. Search for Higgs boson production in trilepton and like-charge electron-muon final states with the D0 detector

    E-Print Network [OSTI]

    D0 Collaboration

    2013-02-22

    We present a search for Higgs bosons in multilepton final states in pp-bar collisions at sqrt(s)=1.96 TeV recorded with the D0 detector at the Fermilab Tevatron Collider, using the full Run II data set with integrated luminosities of up to 9.7 fb-1. The multilepton states considered are two electron plus muon, electron with two muons, muon with two hadronic tau leptons, and like-charge electron-muon pairs. These channels directly probe the HVV (V=W,Z) coupling of the Higgs boson in production and decay. The muon with two hadronic tau lepton channel is also sensitive to H to tau lepton pair decays. Upper limits at the 95% C.L on the rate of standard model Higgs boson production are derived in the mass range 100 Higgs boson model.

  11. Polarized Lepton-Nucleon Elastic Scattering and a Search for a Light Scalar Boson

    E-Print Network [OSTI]

    Yu-Sheng Liu; Gerald A. Miller

    2015-07-15

    Lepton-nucleon elastic scattering, using the one-photon and one-scalar-boson exchange mechanisms considering all possible polarizations, is used to study searches for a new scalar boson and suggest new measurements of the nucleon form factors. A new light scalar boson, which feebly couples to leptons and nucleons, may account for the proton radius and muon $g-2$ puzzles. We show that the scalar boson produces relatively large effects in certain kinematic region when using sufficient control of lepton and nucleon spin polarization. We generalize current techniques to measure the ratio $G_E/G_M$ and present a new method to separately measure $G_M^2$ and $G_E^2$ using polarized incoming and outgoing muons.

  12. Lepton Flavor Non-Universality in B-meson Decays from a U(2) Flavor Model

    E-Print Network [OSTI]

    Falkowski, Adam; Ziegler, Robert

    2015-01-01

    We address the recent anomalies in semi-leptonic $B$-meson decays using a model of fermion masses based on the $U(2)$ flavor symmetry. The new contributions to $b \\to s \\ell \\ell$ transitions arise due to a tree-level exchange of a $Z^\\prime$ vector boson gauging a $U(1)$ subgroup of the flavor symmetry. They are controlled by a single parameter and are approximately aligned to the Standard Model prediction, with constructive interference in the $e$-channel and destructive interference in the $\\mu$-channel. The current experimental data on semi-leptonic $B$-meson decays can be very well reproduced without violating existing constraints from flavor violation in the quark and lepton sectors. Our model will be tested by new measurements of $b \\to s \\ell \\ell$ transitions and also by future electroweak precision tests, direct $Z^\\prime$ searches, and $\\mu$-$e$ conversion in nuclei.

  13. Lepton Flavor Non-Universality in B-meson Decays from a U(2) Flavor Model

    E-Print Network [OSTI]

    Adam Falkowski; Marco Nardecchia; Robert Ziegler

    2015-09-03

    We address the recent anomalies in semi-leptonic $B$-meson decays using a model of fermion masses based on the $U(2)$ flavor symmetry. The new contributions to $b \\to s \\ell \\ell$ transitions arise due to a tree-level exchange of a $Z^\\prime$ vector boson gauging a $U(1)$ subgroup of the flavor symmetry. They are controlled by a single parameter and are approximately aligned to the Standard Model prediction, with constructive interference in the $e$-channel and destructive interference in the $\\mu$-channel. The current experimental data on semi-leptonic $B$-meson decays can be very well reproduced without violating existing constraints from flavor violation in the quark and lepton sectors. Our model will be tested by new measurements of $b \\to s \\ell \\ell$ transitions and also by future electroweak precision tests, direct $Z^\\prime$ searches, and $\\mu$-$e$ conversion in nuclei.

  14. Type Ia Supernovae

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two Electron Holes in HematiteType Ia Supernovae Type Ia

  15. Lineshape of the Higgs boson in future lepton colliders

    E-Print Network [OSTI]

    Jadach, S

    2015-01-01

    The effect of the photon emission (bremsstrahlung) in the cross section of the process of direct production of the Higgs boson in the future high luminosity electron and muon colliders is calculated. It was found that cross section at the top of the Higgs boson resonance peak is reduced by factor 0.347 for the electron collider and 0.548 for the muon collider. Machine spread of the centre of the mass energy of 4.2MeV (equal to the Higgs width) would reduce peak cross section further, by factor 0.170 and 0.256 (QED and energy spread) for electron and muon beams respectively. Possible uncertainties in the resummed QED calculations are discussed. Numerical results for the lineshape cross section including QED and many values of the machine energy spread are provided.

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

    E-Print Network [OSTI]

    Taylor, Frank E.

    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 ?+??] ...

  17. Angular correlations of lepton pairs from vector boson and top quark decays in Monte Carlo simulations

    E-Print Network [OSTI]

    S. Frixione; E. Laenen; P. Motylinski; B. R. Webber

    2007-02-20

    We explain how angular correlations in leptonic decays of vector bosons and top quarks can be included in Monte Carlo parton showers, in particular those matched to NLO QCD computations. We consider the production of $n$ pairs of leptons, originating from the decays of $n$ electroweak vector bosons or of $n$ top quarks, in the narrow-width approximation. In the latter case, the information on the $n$ $b$ quarks emerging from the decays is also retained. We give results of implementing this procedure in MC@NLO

  18. Leptogenesis from right-handed neutrino decays to right-handed leptons

    E-Print Network [OSTI]

    Thomas Hambye

    2006-06-16

    We investigate what would be the consequences for leptogenesis of the existence of a charged SU(2)_L singlet scalar delta^+. If such a scalar particle exists, it allows the right-handed neutrinos to couple not only to left-handed lepton and Higgs doublets as in ordinary leptogenesis, but also to a right-handed charged lepton and a delta^+. This provides a new source of leptogenesis which can be successful in a non-resonant way at scales as low as TeV. The incorporation of this scenario in left-right symmetric and unified models is discussed.

  19. Hadron-Pair Photoproduction in Longitudinally Polarized Lepton-Nucleon Collisions

    E-Print Network [OSTI]

    Hendlmeier, C; Schäfer, A

    2006-01-01

    We present a detailed phenomenological study of photoproduction of two hadrons, both with high transverse momentum, in longitudinally polarized lepton-nucleon collisions. We consistently include ``direct'' and ``resolved'' photon contributions and examine the sensitivity of the relevant spin asymmetries to the gluon polarization in the nucleon and to the completely unknown parton content of circularly polarized photons. Our results are relevant for the COMPASS and HERMES fixed-target experiments as well as for a possible future polarized lepton-proton collider like eRHIC at BNL. So far, all studies are limited to the lowest order approximation of QCD.

  20. Hadron-Pair Photoproduction in Longitudinally Polarized Lepton-Nucleon Collisions

    E-Print Network [OSTI]

    C. Hendlmeier; M. Stratmann; A. Schafer

    2006-06-08

    We present a detailed phenomenological study of photoproduction of two hadrons, both with high transverse momentum, in longitudinally polarized lepton-nucleon collisions. We consistently include ``direct'' and ``resolved'' photon contributions and examine the sensitivity of the relevant spin asymmetries to the gluon polarization in the nucleon and to the completely unknown parton content of circularly polarized photons. Our results are relevant for the COMPASS and HERMES fixed-target experiments as well as for a possible future polarized lepton-proton collider like eRHIC at BNL. So far, all studies are limited to the lowest order approximation of QCD.

  1. Searching for Single Production of Charged Heavy Leptons via Anomalous Interactions at CLIC

    E-Print Network [OSTI]

    A. T. Tasci; A. Senol

    2013-01-07

    We consider the possible discovery potential for single production of charged heavy leptons via anomalous interactions at the envisaged Compact Linear Collider (CLIC) by taking into account initial state radiation (ISR) and beamstrahlung effects. We calculate the production cross sections and decay widths of charged heavy leptons in the context of anomalous interactions at center of mass energies $\\sqrt{s}=1$ and 3 TeV. The signal and corresponding backgrounds are studied in detail for the mass range 300-1900 GeV.

  2. Phenomenology of Maximal and Near-Maximal Lepton Mixing

    E-Print Network [OSTI]

    M. C. Gonzalez-Garcia; C. Peña-Garay; Y. Nir; A. Yu. Smirnov

    2000-09-18

    We study the phenomenological consequences of maximal and near-maximal mixing of the electron neutrino with other ($x$=tau and/or muon) neutrinos. We describe the deviations from maximal mixing in terms of a parameter $\\epsilon\\equiv1-2\\sin^2\\theta_{ex}$ and quantify the present experimental status for $|\\epsilon|neutrinoless double beta decay.

  3. Anomalous magnetic moments of free and bound leptons

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    ]. An almost simultaneous calculation by Schwinger [2] showed how the electron self-interaction explains. Jentschura. Max­Planck­Institut f¨ur Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany. e-mail: Ulrich.Jentschura@mpi-hd.mpg to know this part with the maximum possible accuracy. Schwinger's calculation included a single virtual

  4. Search for Lepton Flavor Violating Decays tau--->l-Ks0 with the BABAR Experiment

    E-Print Network [OSTI]

    Fisher, Peter H.

    A search for the lepton flavor violating decays tau--->l-KS0 (l=e or mu) has been performed using a data sample corresponding to an integrated luminosity of 469??fb[superscript -1], collected with the BABAR detector at the ...

  5. DIFFRACTION 2000 SESSION: `Di raction in lepton-hadron collisions I'

    E-Print Network [OSTI]

    DIFFRACTION 2000 SESSION: `Di#11;raction in lepton-hadron collisions I' September 2 - 7, 2000; Conclusions #12; DIFFRACTION 2000 Paul Thompson Why measure open charm in di#11;raction ? #15; Charm mass Interactions? September 2000 2 #12; DIFFRACTION 2000 Paul Thompson Event Kinematics x IP = M 2 X +Q 2 W 2 +Q 2

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

    E-Print Network [OSTI]

    Boyer, Edmond

    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

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

    E-Print Network [OSTI]

    Gomez-Ceballos, Guillelmo

    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 ...

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

    E-Print Network [OSTI]

    Evelyne Delmeire

    2007-05-15

    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.

  9. Discrimination of models including doubly charged scalar bosons by using tau lepton decay distributions

    E-Print Network [OSTI]

    Hiroaki Sugiyama; Koji Tsumura; Hiroshi Yokoya

    2012-10-05

    The doubly charged scalar boson (H^{\\pm\\pm}) is introduced in several models of the new physics beyond the standard model. The H^{\\pm\\pm} has Yukawa interactions with two left-handed charged leptons or two right-handed charged leptons depending on the models. We study kinematical properties of H^{\\pm\\pm} decay products through tau leptons in order to discriminate the chiral structures of the new Yukawa interaction. The chirality of tau leptons can be measured by the energy distributions of the tau decay products, and thus the chiral structure of the new Yukawa interaction can be traced in the invariant-mass distributions of the H^{\\pm\\pm} decay products. We perform simulation studies for the typical decay patterns of the H^{\\pm\\pm} with simple event selections and tau-tagging procedures, and show that the chiral structure of the Yukawa interactions of H^{\\pm\\pm} can be distinguished by measuring the invariant-mass distributions.

  10. The double mass hierarchy pattern: simultaneously understanding quark and lepton mixing

    E-Print Network [OSTI]

    Hollik, Wolfgang Gregor

    2015-01-01

    The charged fermion masses of the three generations exhibit the two strong hierarchies m_3 >> m_2 >> m_1. We assume that also neutrino masses satisfy m_{nu 3} > m_{nu 2} > m_{nu 1} and derive the consequences of the hierarchical spectra on the fermionic mixing patterns. The quark and lepton mixing matrices are built in a general framework with their matrix elements expressed in terms of the four fermion mass ratios m_u/m_c, m_c/m_t, m_d/m_s, and m_s/m_b and m_e/m_mu, m_mu/m_tau, m_{nu 1}/m_{nu 2}, and m_{nu 2}/m_{nu 3}, for the quark and lepton sector, respectively. In this framework, we show that the resulting mixing matrices are consistent with data for both quarks and leptons, despite the large leptonic mixing angles. The minimal assumption we take is the one of hierarchical masses and minimal flavour symmetry breaking that strongly follows from phenomenology. No special structure of the mass matrices has to be assumed that cannot be motivated by this minimal assumption. This analysis allows us to predict ...

  11. Non-perturbative Heavy Quark Effective Theory: An application to semi-leptonic B-decays

    E-Print Network [OSTI]

    Michele Della Morte; Jochen Heitger; Hubert Simma; Rainer Sommer

    2015-01-14

    We review a lattice strategy how to non-perturbatively determine the coefficients in the HQET expansion of all components of the heavy-light axial and vector currents, including 1/m_h-corrections. We also discuss recent preliminary results on the form factors parameterizing semi-leptonic B-decays at the leading order in 1/m_h.

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

    E-Print Network [OSTI]

    Apyan, Aram

    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 ...

  13. 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

  14. Drell-Yan Lepton pair production at NNLO QCD with parton showers

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

    Hoeche, Stefan; Li, Ye; Prestel, Stefan

    2015-04-13

    We present a simple approach to combine NNLO QCD calculations and parton showers, based on the UNLOPS technique. We apply the method to the computation of Drell-Yan lepton-pair production at the Large Hadron Collider. We comment on possible improvements and intrinsic uncertainties.

  15. Search for the Standard Model Higgs Boson in the H -> WW -> lepton+neutrino+q'qbar Decay Channel

    SciTech Connect (OSTI)

    Abazov, Victor Mukhamedovich; et al.

    2011-04-01

    We present a search for the standard model Higgs boson (H) in ppbar collisions at sqrt{s}=1.96 TeV in events containing a charged lepton (ell), missing transverse energy, and at least two jets, using 5.4 fb^-1 of integrated luminosity recorded with the D0 detector at the Fermilab Tevatron Collider. This analysis is sensitive primarily to Higgs bosons produced through the fusion of two gluons or two electroweak bosons, with subsequent decay H->WW->ell+nu+q'qbar, where ell is an electron or muon. The search is also sensitive to contributions from other production channels, such as WH->ell+nu+bbbar In the absence of signal, we set limits at the 95% C.L. on the cross section for H production sigma(ppbar->H+X) in these final states. For a mass of MH=160 GeV, the limit is a factor of 3.9 larger than the cross section in the standard model, and consistent with expectation.

  16. Search for production of WW / WZ resonances decaying to a lepton, neutrino and jets in pp collisions at ?s = 8 TeV with the ATLAS detector

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

    Aad, G.

    2015-05-12

    In this study, a search is presented for narrow diboson resonances decaying to WW or WZ in the final state where one W boson decays leptonically (to an electron or a muon plus a neutrino) and the other W/Z boson decays hadronically. The analysis is performed using an integrated luminosity of 20.3 fb–1 of pp collisions at ?s = 8 TeV collected by the ATLAS detector at the large hadron collider. No evidence for resonant diboson production is observed, and resonance masses below 700 and 1490 GeV are excluded at 95% confidence level for the spin-2 Randall–Sundrum bulk graviton G*more »with coupling constant of 1.0 and the extended gauge model W' boson respectively.« less

  17. Search for supersymmetry in pp collisions at sqrt(s)=7 TeV in events with a single lepton, jets, and missing transverse momentum

    SciTech Connect (OSTI)

    Chatrchyan, Serguei; et al.

    2011-08-01

    Results are reported from a search for physics beyond the standard model in proton-proton collisions at a center-of-mass energy of 7 TeV, focusing on the signature with a single, isolated, high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The data sample comprises an integrated luminosity of 36 inverse picobarns, recorded by the CMS experiment at the LHC. The search is motivated by models of new physics, including supersymmetry. The observed event yields are consistent with standard model backgrounds predicted using control samples obtained from the data. The characteristics of the event sample are consistent with those expected for the production of t t-bar and W +jets events. The results are interpreted in terms of limits on the parameter space for the constrained minimal supersymmetric extension of the standard model.

  18. ATLAS search for a heavy gauge boson decaying to a charged lepton and a neutrino in pp collisions at ?s = 7 TeV

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

    Aad, G.

    2012-12-08

    The ATLAS detector at the LHC is used to search for high-mass states, such as heavy charged gauge bosons (W'), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp collisions at a centre-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.7 fb-1. No excess beyond Standard Model expectations is observed. A W' with Sequential Standard Model couplings is excluded at the 95% credibility level for masses up to 2.55 TeV. Excited chiral bosons (W*) with equivalent coupling strength are excluded for masses up to 2.42 TeV.

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

    SciTech Connect (OSTI)

    Fedorko, Wojciech T.; /Chicago U.

    2008-09-01

    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.

  20. Search for a heavy gauge boson decaying to a charged lepton and a neutrino in 1 fb-1 of pp collisions at ?s=7 TeV using the ATLAS detector

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

    Aad, G.

    2011-11-01

    The ATLAS detector at the LHC is used to search for heavy charged gauge bosons (W'), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 1.04 fb?¹. No excess beyond Standard Model expectations is observed. A W' with Sequential Standard Model couplings is excluded at the 95% confidence level for masses up to 2.15 TeV.

  1. Electroweak quark-lepton symmetry and weak topological-charge confinement in the Standard Model with Dirac neutrinos

    E-Print Network [OSTI]

    Ernesto A. Matute

    2007-09-25

    The standard electroweak model with Dirac neutrinos is extended by way of the principles of electroweak quark-lepton symmetry and weak topological-charge confinement to account for quark-lepton charge relations which, if not accidental, are indicative of charge structures. A mixing in quarks and leptons of underlying integer local charges with integer weak topological charges associated with an additive group Z_3, fixed by the anomaly cancellation requirement, is discussed. It is found that the electroweak difference between topological quarks and leptons is the nonequivalence between the topological vacua of their weak field configurations, produced by a four-instanton which carries the topological charge, induces the universal fractional piece of charge distinguishing quarks from leptons, and breaks the underlying symmetry. The constituent quarks of the standard model appear as coming from topological quarks, via the weak four-instanton event. Dual transitions occur for leptons. It is shown that several other fundamental problems left open in the standard electroweak model with Dirac neutrinos are solved: the one-to-one correspondence between quark and lepton flavors, the existence of three generations, the conservation and ungauging of B-L, the electric charge quantization, and the confinement of fractional electric charges.

  2. Light top squarks in $U(1)_{R}$-lepton number model with a right handed neutrino and the LHC

    E-Print Network [OSTI]

    Chakraborty, Sabyasachi; Huitu, Katri; Roy, Sourov; Waltari, Harri

    2015-01-01

    We investigate the phenomenology of top squarks at the Large Hadron Collider (LHC) in a supersymmetric model where lepton number is identified with an approximate $U(1)_R$ symmetry in such a way that one of the left chiral sneutrinos can acquire a large vacuum expectation value ($vev$) and can play the role of the down-type Higgs. This $R$-symmetry allows a subset of trilinear $R$-parity violating interactions, which determine the collider phenomenology of this model in a significant way. The gauginos are Dirac particles and gluinos are relatively heavy in this class of models. The model contains a right handed neutrino superfield, which gives a tree level mass to one of the active neutrinos. An order one neutrino Yukawa coupling also helps enhance the Higgs boson mass at the tree level and results in a very light bino-like neutralino ($\\widetilde \\chi_2^0$) with mass around a few hundred MeV, which is a carrier of missing (transverse) energy (\\met). The model can accommodate two rather light top squarks, com...

  3. Blood Types

    E-Print Network [OSTI]

    Hacker, Randi; Tsutsui, William

    2007-03-14

    Sox spent a hundred mil to acquire pitcher Daisuke Matsuzaka; they probably weren't even aware that he is a Type O and that they make the best bankers, politicians and... you guessed it... professional baseball players. #ceas #hacker #japan #tsutsuien...

  4. Probing the fermionic Higgs portal at lepton colliders

    E-Print Network [OSTI]

    Fedderke, Michael A; Wang, Lian-Tao

    2015-01-01

    We study the sensitivity of future electron-positron colliders to UV completions of the fermionic Higgs portal operator $H^\\dagger H \\bar \\chi \\chi$. Measurements of precision electroweak $S$ and $T$ parameters and the $e^+e^- \\to Zh$ cross section at the CEPC, FCC-ee, and ILC are considered. The scalar completion of the fermionic Higgs portal is closely related to the scalar Higgs portal, and we summarize existing results. We devote the bulk of our analysis to a singlet-doublet fermion completion. Assuming the doublet is sufficiently heavy, we construct the effective field theory (EFT) at dimension-6 in order to compute contributions to the observables. We also provide full one-loop results for $S$ and $T$ in the general mass parameter space. In both completions, future precision measurements can probe the new states at the (multi-)TeV scale, beyond the direct reach of the LHC.

  5. Probing the fermionic Higgs portal at lepton colliders

    E-Print Network [OSTI]

    Michael A. Fedderke; Tongyan Lin; Lian-Tao Wang

    2015-06-17

    We study the sensitivity of future electron-positron colliders to UV completions of the fermionic Higgs portal operator $H^\\dagger H \\bar \\chi \\chi$. Measurements of precision electroweak $S$ and $T$ parameters and the $e^+e^- \\to Zh$ cross section at the CEPC, FCC-ee, and ILC are considered. The scalar completion of the fermionic Higgs portal is closely related to the scalar Higgs portal, and we summarize existing results. We devote the bulk of our analysis to a singlet-doublet fermion completion. Assuming the doublet is sufficiently heavy, we construct the effective field theory (EFT) at dimension-6 in order to compute contributions to the observables. We also provide full one-loop results for $S$ and $T$ in the general mass parameter space. In both completions, future precision measurements can probe the new states at the (multi-)TeV scale, beyond the direct reach of the LHC.

  6. Proca Equation for Attosecond Electron Pulses

    E-Print Network [OSTI]

    Magdalena Pelc; Janina Marciak-Kozlowska; Miroslaw Kozlowski

    2008-03-03

    In this paper the heat transport of attosecond electron pulses is investigated. It is shown that attosecond electrons can propagate as thermal waves or diffused as particle conglommerates, Proca equation as type equation for the thermal transport of the attosecond electron pulsem is formulated

  7. Search for excited leptons in proton-proton collisions at ?s=7??TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector is used to search for excited leptons in the electromagnetic radiative decay channel ?*???. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding ...

  8. Search for new physics in final states with a lepton and missing transverse energy in pp collisions at the LHC

    E-Print Network [OSTI]

    Apyan, Aram

    This Letter describes the search for an enhanced production rate of events with a charged lepton and a neutrino in high-energy pp collisions at the LHC. The analysis uses data collected with the CMS detector, with an ...

  9. Search for new physics in final states with a lepton and missing transverse energy in pp collisions at the LHC

    E-Print Network [OSTI]

    Baringer, Philip S.; Bean, Alice; Benelli, Gabriele; Kenny, R. P. III; Murray, Michael J.; Noonan, Danny; Sanders, Stephen J.; Stringer, Robert W.; Tinti, Gemma; Wood, Jeffrey Scott; Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.; Dragicevic, M.

    2013-04-08

    This Letter describes the search for an enhanced production rate of events with a charged lepton and a neutrino in high-energy pp collisions at the LHC. The analysis uses data collected with the CMS detector, with an ...

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

    E-Print Network [OSTI]

    Monika Sinha; Banibrata Mukhopadhyay

    2007-11-21

    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.

  11. Fourth Generation Lepton Sectors with Stable Majorana Neutrinos: From LEP to LHC

    E-Print Network [OSTI]

    Linda M. Carpenter

    2010-10-26

    I analyze a fourth generation lepton sector in which the lightest particle is a stable Majorana neutrino. In this scenario fourth generation neutrinos have both a Dirac and Majorana mass, resulting in two Majorana neutrino mass eigenstates. A reanalysis of LEP's lower mass bound is performed on stable Majorana neutrinos from the Z width and the lower mass bound is loosened. I also extrapolate LEP's SUSY squark search with a 2 jet plus missing missing energy final state to the production and decay of a pair of heavy Majorana neutrinos; here it is expected that significant regions of the neutrino mass plane may be ruled out. Finally, a search strategy is proposed for heavy fourth generation neutrino pairs at LHC in the four lepton plus missing energy channel. Exclusions are set in the neutrino mass plane for 30 inverse fb of data at LHC for 13 TeV.

  12. Lepton-flavor-violating decay {tau}{yields}{mu}{mu}{mu} at the CERN LHC

    SciTech Connect (OSTI)

    Giffels, M.; Stahl, A. [III. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); Kallarackal, J. [Institut fuer Theoretische Physik, RWTH Aachen, 52074 Aachen (Germany); Institut fuer Physik, Humboldt-Universitaet zu Berlin, 12489 Berlin (Germany); Kraemer, M.; O'Leary, B. [Institut fuer Theoretische Physik, RWTH Aachen, 52074 Aachen (Germany)

    2008-04-01

    Lepton-flavor-violating {tau} decays are predicted in many extensions of the standard model at a rate observable at future collider experiments. In this article we focus on the decay {tau}{yields}{mu}{mu}{mu}, which is a promising channel to observe lepton-flavor violation at the CERN Large Hadron Collider (LHC). We present analytic expressions for the differential decay width derived from a model-independent effective Lagrangian with general four-fermion operators, and estimate the experimental acceptance for detecting the decay {tau}{yields}{mu}{mu}{mu} at the LHC. Specific emphasis is given to decay angular distributions and how they can be used to discriminate new physics models. We provide specific predictions for various extensions of the standard model, including supersymmetric, little Higgs, and technicolor models.

  13. $S_3$ as a unified family theory for quarks and leptons

    E-Print Network [OSTI]

    Canales, F González; Salazar, U J Saldaña; Velasco-Sevilla, L

    2012-01-01

    We present an $S_3$-invariant extension of the SM which is able to account for the mixing both in the quark and the lepton sector. We focus here on the quark sector and present different realizations of the model, according to how many Higgs fields are involved. We then confront the models with the up-to-date values of masses and mixing in the quark sector.

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

    SciTech Connect (OSTI)

    Canepa, Anadi; /Purdue U.

    2006-02-01

    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.

  15. Derived Types What Are Derived Types?

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Derived Types #12;What Are Derived Types? As usual, a hybrid of two, unrelated concepts C++, Python orientation comes in #12;Simple Derived Types TYPE Wheel INTEGER :: spokes REAL :: diameter, width CHARACTER(LEN=15) :: material END TYPE Wheel That defines a derived type Wheel Using derived types needs a special

  16. Derived Types What Are Derived Types?

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Derived Types #12;What Are Derived Types? As usual, a hybrid of two, unrelated concepts C object orientation comes in This course will only describe the former. #12;Simple Derived Types TYPE That defines a derived type Wheel Using derived types needs a special syntax TYPE(Wheel) :: w1 #12;More

  17. Statistical Constraints on the Error of the Leptonic CP Violation of Neutrinos

    E-Print Network [OSTI]

    Fu, Kai

    2015-01-01

    A constraint on the error of leptonic CP violation, which require the phase $\\delta_{CP}$ to be less than $\\pi/4$ for it to be distinguishable on a $2\\pi$ cycle, is presented. Under this constraint, the effects of neutrino detector 's distance, beam energy, and energy resolution are discussed with reference to the present values of these parameters in experiments. Although an optimized detector performances can minimize the deviation to yield a larger distinguishable range of the leptonic CP phase on a $2\\pi$ cycle, it is not possible to determine an arbitrary leptonic CP phase in the range of $2\\pi$ with the statistics from a single detector because of the existence of two singular points. An efficiency factor $\\eta$ is defined to characterize the distinguishable range of $\\delta_{CP}$. To cover the entire possible $\\delta_{CP}$ range, a combined efficiency factor $\\eta^*$ corresponding to multiple sets of detection parameters with different neutrino beam energies and distances is proposed. The combined effi...

  18. Statistical Constraints on the Error of the Leptonic CP Violation of Neutrinos

    E-Print Network [OSTI]

    Kai Fu; Ying Zhang

    2015-04-28

    A constraint on the error of leptonic CP violation, which require the phase $\\delta_{CP}$ to be less than $\\pi/4$ for it to be distinguishable on a $2\\pi$ cycle, is presented. Under this constraint, the effects of neutrino detector 's distance, beam energy, and energy resolution are discussed with reference to the present values of these parameters in experiments. Although an optimized detector performances can minimize the deviation to yield a larger distinguishable range of the leptonic CP phase on a $2\\pi$ cycle, it is not possible to determine an arbitrary leptonic CP phase in the range of $2\\pi$ with the statistics from a single detector because of the existence of two singular points. An efficiency factor $\\eta$ is defined to characterize the distinguishable range of $\\delta_{CP}$. To cover the entire possible $\\delta_{CP}$ range, a combined efficiency factor $\\eta^*$ corresponding to multiple sets of detection parameters with different neutrino beam energies and distances is proposed. The combined efficiency factors $\\eta^*$ of various major experiments are also presented.

  19. Search for lepton flavor violating decay $\\tau^- \\to \\ell^- \\ell^ \\ell^-$ at BaBar

    SciTech Connect (OSTI)

    Cervelli, Alberto; /Pisa U.

    2010-05-26

    The Standard Model (SM) is one of the most tested and verified physical theories of all time, present experimental observations are consistent with SM expectations. On the other hand SM can not explain many physical observations: the cosmological observations possibly infer the presence of dark matter which is clearly beyond the SM expectations; the SM Higgs model, while explaining the generation of fermion masses, can not explain the hierarchy problem and a non natural fine tuning of SM is needed to cancel out quadratic divergences in the Higgs boson mass. New physics (NP) beyond SM should hence be investigated: rising the energy above NP processes thresholds, and detecting new particles or new effects not predicted by the standard model directly, is one of the possible approaches; another approach is to make precision measurements of well known processes or looking for rare processes which involve higher order contribution from NP processes, this approach need higher luminosities with respect to the previous approach but lower beam energies. Search for Lepton Flavor Violation (LFV) in charged lepton decays is promising: neutrino physics provides indeed a clear and unambiguous evidence of LFV in the neutral lepton sector via mixing processes, which have been observed for the first time by the Homestake collaboration. We expect LFV in the charged sector as well, both in {mu} and {tau} sector, but current experimental searches for LFV processes did not find any evidence for those processes, and more results are expected to come from new experiments in the coming years.

  20. Type: Renewal

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCEDInstallers/ContractorsPhotovoltaicsStateof Energy TwoEvent at the Pu Facility,Type IV COPV1

  1. Electron microscope phase enhancement

    DOE Patents [OSTI]

    Jin, Jian; Glaeser, Robert M.

    2010-06-15

    A microfabricated electron phase shift element is used for modifying the phase characteristics of an electron beam passing though its center aperture, while not affecting the more divergent portion of an incident beam to selectively provide a ninety-degree phase shift to the unscattered beam in the back focal plan of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. One application of the element is to increase the contrast of an electron microscope for viewing weakly scattering samples while in focus. Typical weakly scattering samples include biological samples such as macromolecules, or perhaps cells. Preliminary experimental images demonstrate that these devices do apply a ninety degree phase shift as expected. Electrostatic calculations have been used to determine that fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature-size aperture is about 5:1. Calculations are underway to determine the feasibility of aspect smaller aspect ratios of about 3:1 and about 2:1.

  2. Two-photon exchange measurements with positrons and electrons

    E-Print Network [OSTI]

    John Arrington

    2009-05-05

    Two-photon exchange contributions have potentially broad ranging impact on several charged lepton scattering measurements. Previously believed to be extremely small, based in part on comparisons of positron scattering and electron scattering in the 1950s and 1960s, recent data suggest that the corrections may be larger than expected, in particular in kinematic regions that were inaccessible in these early positron scattering measurements. Additional measurements using positron beams at Jefferson Lab would allow for a detailed investigation of these contributions in a range of reactions and observables.

  3. Synthesis, structural characterization and properties of SrAl{sub 4?x}Ge{sub x}, BaAl{sub 4?x}Ge{sub x}, and EuAl{sub 4?x}Ge{sub x} (x?0.3–0.4)—Rare examples of electron-rich phases with the BaAl{sub 4} structure type

    SciTech Connect (OSTI)

    Zhang, Jiliang; Bobev, Svilen, E-mail: bobev@udel.edu

    2013-09-15

    Three solid solutions with the general formula AEAl{sub 4?x}Ge{sub x} (AE=Eu, Sr, Ba; 0.32(1)?x?0.41(1)) have been synthesized via the aluminum self-flux method, and their crystal structures have been established from powder and single-crystal X-ray diffraction. They are isotypic and crystallize with the well-known BaAl{sub 4} structure type, adopted by the three AEAl{sub 4} end members. In all structures, Ge substitutes Al only at the 4e Wyckoff site. Results from X-rays photoelectron spectroscopy on EuAl{sub 4?x}Ge{sub x} and EuAl{sub 4} indicate that the interactions between the Eu{sup 2+} cations and the polyanionic framework are enhanced in the Ge-doped structure, despite the slightly elevated Fermi level. Magnetic susceptibility measurements confirm the local moment magnetism, expected for the [Xe]4f{sup 7} electronic configuration of Eu{sup 2+} and suggest strong ferromagnetic interactions at cryogenic temperatures. Resistivity data from single-crystalline samples show differences between the title compounds, implying different bonding characteristics despite the close Debye temperatures. A brief discussion on the observed electron count and homogeneity ranges for AEAl{sub 4?x}Ge{sub x} (AE=Eu, Sr, Ba) is also presented. - Graphical abstract: AEAl{sub 4?x}Ge{sub x} (AE=Eu, Sr, Ba; 0.32(1)?x?0.41(1)), three “electron-rich” phases with BaAl{sub 4} structure type have been synthesized and characterized. Display Omitted - Highlights: • Three BaAl{sub 4}-type ternary aluminum germanides have been synthesized with Eu, Sr and Ba. • Eu, Sr and Ba cations have no apparent influence on the solubility of Ge. • The Ge atoms substitute Al on one of two framework sites, thereby strengthening the interactions between the cations and the polyanionic framework.

  4. Centrality dependence of heavy flavor production from single electron measurement

    E-Print Network [OSTI]

    J. Bielcik

    2005-11-01

    We present preliminary measurements of electron production in p+p, d+Au, and Au+Au collisions at $\\sqrt{s_{NN}}$=200 GeV for transverse momenta 1.5 GeV/$c$ $measurements were carried out using the STAR Time Projection Chamber and Barrel Electromagnetic Calorimeter. In this manuscript we describe the measurement techniques used to discriminate electrons from hadrons and the method used to evaluate the non-photonic contributions from semi-leptonic decays of heavy flavor mesons. The observed nuclear modification factors, $R_{AA}$, of non-photonic electrons indicate at substantial energy loss of heavy quarks at moderate to high $p_T$.

  5. Electron tube

    DOE Patents [OSTI]

    Suyama, Motohiro (Hamamatsu, JP); Fukasawa, Atsuhito (Hamamatsu, JP); Arisaka, Katsushi (Los Angeles, CA); Wang, Hanguo (North Hills, CA)

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  6. COLLOQUIUM: Type II Solar Radio Bursts: From Fundamental Plasma...

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

    coherent radio emission stimulated by shocks. Type II bursts are widely accepted to be radio emission produced at the electron plasma frequency andor twice that frequency...

  7. UHE Leptons and Neutrons feeding Precessing gamma Jet in GRBs - SGRs: A SGR 1806-20 link to EeV C.R.?

    E-Print Network [OSTI]

    D. Fargion; M. Grossi

    2005-05-09

    Soft Gamma Repeaters are widely believed to occur as isotropic Magnetar explosion. We suggest on the contrary that they may be described by thin collimated spinning and precessing Gamma Jets flashing and blazing along the line of sight. The Jet (for SGRs) maybe powered by an accretion disk in binary system and it reproduces huge outflow and oscillating blazing mode as the observed ones in Giant Flare SGR 1806-20. The precessing and spinning blazing nature reflects at smaller intensity the same behavior observed in brief GRBs Jetted Supernova, as well as re-brightening and bumps in afterglows. The SGR gamma beam maybe powered by Inverse Compton Scattering or by Synchrotron Radiation of electron pair beam respectively at GeVs or PeVs energies. In the latter case tens PeVs leptons (muons and later decaying PeVs electrons) might be originated while EeV nucleons Jets (protons-neutrons) are in photo-pion equilibrium with infrared photons surrounding the source. The neutron Jet might survive and remain collimated. It maybe already detected as an EeV cosmic ray anisotropy in present AGASA map pointing toward known (North Hemisphere) SGRs : SGR 1900 +14 and SGR 1806-20. If the SGR-EeV connection is correct a parasite traces of PeVs neutrino as well PeV-TeVs gamma rays might be found in present or future data records, among the others C.R. array detectors, inside the Amanda and Milagro volumes.

  8. Electronic Fireflies

    E-Print Network [OSTI]

    Hacker, Randi; Greene, Megan

    2009-01-28

    . The Japanese: firefly connection goes back to the 8th Century when poets used them to represent human passions. But pollution and development have depleted the number of fireflies. So what's a New Year's reveler to do? Buy Denshi Hotaru, life-sized, electronic...

  9. First principles study of the structural, elastic, electronic and phonon properties of CdX{sub 2}O{sub 4} (X=Al, Ga, In) spinel-type oxides

    SciTech Connect (OSTI)

    Candan, Abdullah; U?ur, Gökay

    2014-10-06

    We have performed ab-initio calculations of the structural, electronic, elastic and dynamical properties for the spinel compounds CdX{sub 2}O{sub 4} (X=Al, Ga, In) using the plane wave pseudo-potential method within the generalized gradient approximation (GGA). The calculated lattice parameters, elastic constants for these compounds are in good agreement with the previous calculated values. The computed direct band gaps of CdAl{sub 2}O{sub 4}, CdGa{sub 2}O{sub 4} and CdIn{sub 2}O{sub 4} are 2.90 eV, 1.92 eV and 1.16 eV, respectively. The lattice vibrations were calculated by direct method. The calculated phonon dispersion curves show that all compounds are dynamically stable in the spinel structure.

  10. STUDY TYPES What is a "Study Type"?

    E-Print Network [OSTI]

    Dorf, Martin E.

    #12;STUDY TYPES What is a "Study Type"? A Study Type is a defined business process. Study Types work together to streamline workflow, track data & keep users informed. There are 2 Study Types in eCOMS: COMS and IACUC. The COMS Study: The COMS Study is an online form that a Principal Investigator fills

  11. HERBVI - a program for simulation of baryon- and lepton- number violating processes

    E-Print Network [OSTI]

    M. J. Gibbs; B. R. Webber

    1995-04-05

    We describe a Monte Carlo event generator for the simulation of baryon- and lepton-number violating processes at supercolliders. The package, {\\HERBVI}, is designed as a hard-process generator interfacing to the general hadronic event simulation program {\\HW}. In view of the very high multiplicity of gauge bosons expected in such processes, particular attention is paid to the efficient generation of multiparticle phase space. The program also takes account of the expected colour structure of baryon-number violating vertices, which has important implications for the hadronization of the final state.

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

    SciTech Connect (OSTI)

    Prokudin, Alexey [JLAB

    2015-01-01

    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.

  13. $A_N$ in inclusive lepton-proton collisions: TMD and twist-3 approaches

    E-Print Network [OSTI]

    Alexei Prokudin

    2014-10-14

    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.

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

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

    Prokudin, Alexei

    2015-01-23

    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. As a result, we discuss similarities and differences of two formalisms.

  15. Dark Matter and Lepton Flavour Violation in a Hybrid Neutrino Mass Model

    E-Print Network [OSTI]

    Deppisch, Frank F

    2014-01-01

    We describe a hybrid model in which the light neutrino mass matrix receives both tree-level seesaw and loop-induced contributions. An additional U(1) gauge symmetry is used to stabilize the lightest right-handed neutrino as the Dark Matter candidate. After fitting the experimental neutrino data, we analyze and correlate the phenomenological consequences of the model, namely its impact on electroweak precision measurements, the Dark Matter relic abundance, lepton flavour violating rare decays and neutrinoless double beta decay. We find that natural realizations of the model characterized by large Yukawa couplings are compatible with and close to the current experimental limits.

  16. Further Evidence of Narrow Baryonic Structures with Hadronic as Well as Leptonic Probes

    E-Print Network [OSTI]

    B. Tatischeff; E. Tomasi-Gustafsson

    2004-11-22

    Although extracted from several experiments using hadronic probes \\cite{bor1}, narrow baryonic structures have been sometimes met with disbelief. New signatures are presented, which appear from already published data, obtained with hadronic probes as well as with leptonic probes. The authors of these results did not take into account the possibility to associate the discontinuities of their spectra with the topic of narrow baryonic low mass structures. The stability of the observed narrow structure masses, represents a confirmation of their genuine existence.

  17. Microwave guiding of electrons on a chip

    E-Print Network [OSTI]

    Johannes Hoffrogge; Roman Fröhlich; Mark A. Kasevich; Peter Hommelhoff

    2010-12-10

    Electrons travelling in free space have allowed to explore fundamental physics like the wave nature of matter, the Aharonov-Bohm and the Hanbury Brown-Twiss effect. Complementarily, the precise control over the external degrees of freedom of electrons has proven pivotal for wholly new types of experiments such as high precision measurements of the electron's mass and magnetic moment in Penning traps. Interestingly, the confinement of electrons in the purely electric field of an alternating quadrupole has rarely been considered. Recent advances in the development of planar chip-based ion traps suggest that this technology can be applied to enable entirely new experiments with electron beams guided in versatile potentials. Here we demonstrate the transverse confinement of a low energy electron beam in a linear quadrupole guide based on microstructured planar electrodes and driven at microwave frequencies. A new guided matter-wave system will result, with applications ranging from electron interferometry to novel non-invasive electron microscopy.

  18. The Effects of Fourth Generation on the double Lepton Polarization in B \\rar K \\ell^+ \\ell^- decay

    E-Print Network [OSTI]

    V. Bashiry; S. M. Zebarjad; F. Falahati; K. Azizi

    2008-04-30

    This study investigates the influence of the fourth generation quarks on the double lepton polarizations in B \\rar K \\ell^+ \\ell^- decay. Taking |V_{t's}V_{t'b}|\\sim \\{0.01-0.03\\} with phase about 100^\\circ, which is consistent with the b\\to s\\ell^+\\ell^- rate and the B_s mixing parameter Delta m_{B_s}$, we obtain that the double lepton(muon and tau) polarizations are quite sensitive to the existence of fourth generation. It can serve as a good tool to search for new physics effects, precisely, to indirect search for the fourth generation quarks(t', b').

  19. Neutrino Masses, Lepton Flavor Mixing and Leptogenesis in the Minimal Seesaw Model

    E-Print Network [OSTI]

    Wan-lei Guo; Zhi-zhong Xing; Shun Zhou

    2006-12-05

    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.

  20. A Direct Top-Quark Width Measurement from Lepton + Jets Events at CDF II

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.; Arisawa, T.; /Waseda U. /Dubna, JINR

    2010-08-01

    We present a measurement of the top-quark width using t{bar t} events produced in p{bar p} collisions at Fermilab's Tevatron collider and collected by the CDF II detector. In the mode where the top quark decays to a W boson and a bottom quark, we select events in which one W decays leptonically and the other hadronically (lepton + jets channel) . From a data sample corresponding to 4.3 fb{sup -1} of integrated luminosity, we identify 756 candidate events. The top-quark mass and the mass of W boson that decays hadronically are reconstructed for each event and compared with templates of different top-quark widths ({Lambda}{sub t}) and deviations from nominal jet energy scale ({Delta}{sub JES}) to perform a simultaneous fit for both parameters, where {Delta}{sub JES} is used for the in situ calibration of the jet energy scale. By applying a Feldman-Cousins approach, we establish an upper limit at 95% confidence level (CL) of {Lambda}{sub t} < 7.6 GeV and a two-sided 68% CL interval of 0.3 GeV < {Lambda}{sub t} < 4.4 GeV for a top-quark mass of 172.5 GeV/c{sup 2}, which are consistant with the standard model prediction. This is the first direct measurement of {Lambda}{sub t} to set a lower limit with 68% CL.

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

    E-Print Network [OSTI]

    M. C. Gonzalez-Garcia; Michele Maltoni; Thomas Schwetz

    2014-12-16

    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.

  2. Horizon-Scale Lepton Acceleration in Jets: Explaining the Compact Radio Emission in M87

    E-Print Network [OSTI]

    Tchekhovskoy, Alexander

    2015-01-01

    It has now become clear that the radio jet in the giant elliptical galaxy M87 must turn on very close to the black hole. This implies the efficient acceleration of leptons within the jet at scales much smaller than feasible by the typical dissipative events usually invoked to explain jet synchrotron emission. Here we show that the stagnation surface, the separatrix between material that falls back into the black hole and material that is accelerated outward forming the jet, is a natural site of pair formation and particle acceleration. This occurs via an inverse-Compton pair catastrophe driven by unscreened electric fields within the charge-starved region about the stagnation surface and substantially amplified by a post-gap cascade. For typical estimates of the jet properties in M87, we find excellent quantitive agreement between the predicted relativistic lepton densities and those required by recent high-frequency radio observations of M87. This mechanism fails to adequately fill a putative jet from Sagitt...

  3. Low and high energy phenomenology of quark-lepton complementarity scenarios

    SciTech Connect (OSTI)

    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)

    2007-04-01

    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.

  4. Lepton flavor violation in the supersymmetric seesaw model after the LHC 8 TeV run

    E-Print Network [OSTI]

    Toru Goto; Yasuhiro Okada; Tetsuo Shindou; Minoru Tanaka; Ryoutaro Watanabe

    2014-12-08

    We study the lepton flavor violation in the supersymmetric seesaw model taking into account recent experimental improvements, especially for the Higgs boson mass measurement, direct searches of superpartners and the rare decay of B_s -> mu+ mu- at the LHC, the neutrino mixing angle of theta_{13} at the neutrino experiments, and the search of mu -> e gamma at the MEG experiment. We obtain the latest constraints on the parameters in the supersymmetry breaking terms and study the effect on the lepton flavor violating decays of tau -> mu gamma and mu -> e gamma. In particular, we consider two kinds of assumption on the structures in the Majorana mass matrix and the neutrino Yukawa matrix. In the case of the Majorana mass matrix proportional to the unit matrix, allowing non-vanishing CP violating parameters in the neutrino Yukawa matrix, we find that the branching ratio of tau -> mu gamma can be larger than 10^{-9} within the improved experimental limit of mu -> e gamma. We also consider the neutrino Yukawa matrix that includes the mixing only in the second and third generations, and find that a larger branching ratio of tau -> mu gamma than 10^{-9} is possible with satisfying the recent constraints.

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

    E-Print Network [OSTI]

    Ansgar Denner; Stefan Dittmaier; Markus Hecht; Christian Pasold

    2015-11-12

    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.

  6. Lepton production at the LHC from singly- and doubly-charged bilepton

    SciTech Connect (OSTI)

    Sa Borges, J. [Instituto de Fisica, UERJ, Rio de Janeiro, RJ (Brazil); Coutinho, Y. A. [Instituto de Fisica, UFRJ, Rio de Janeiro, RJ (Brazil); Barreto, E. R. [C C N H, UFABC, Santo Andre, SP (Brazil)

    2013-03-25

    Some extensions of the standard model predict the existence of particles having two units of leptonic charge, known as bileptons. One of such models is based on the SU(3){sub c} Multiplication-Sign SU(3){sub L} Multiplication-Sign U(1){sub X} symmetry group (3-3-1). Our search uses the minimal version of this model, having exotic charges for the quarks and gauge bosons. It predicts the existence of bileptons as vector particles having one unit of electric charge (V{sup {+-}}) or two units of electric charge (Y{sup {+-}{+-}}). Our aim is to establish the signatures for the production of four fermions in pp collisions at the LHC for 7 TeV center of mass energy. We present the total cross section and we show the leptons invariant mass and transverse momentum distributions. We conclude that LHC collider can show a clear signature for a process induced by bileptons as a signal of new physics.

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

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

    Khachatryan, V.

    2014-10-28

    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 MSSMmore »parameter space for different benchmark scenarios, mhmax, mhmod+ , mhmod– , light-stop, light-stau, ?-phobic, and low-mH. Upper limits on the cross section times branching fraction for gluon fusion and b-quark associated Higgs boson production are also given.« less

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

    SciTech Connect (OSTI)

    Khachatryan, V.

    2014-10-28

    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, mhmax, mhmod+ , mhmod– , light-stop, light-stau, ?-phobic, and low-mH. Upper limits on the cross section times branching fraction for gluon fusion and b-quark associated Higgs boson production are also given.

  9. P-type gallium nitride

    DOE Patents [OSTI]

    Rubin, Michael (Berkeley, CA); Newman, Nathan (Montara, CA); Fu, Tracy (Berkeley, CA); Ross, Jennifer (Pleasanton, CA); Chan, James (Berkeley, CA)

    1997-01-01

    Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5.times.10.sup.11 /cm.sup.3 and hole mobilities of about 500 cm.sup.2 /V-sec, measured at 250.degree. K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al.

  10. P-type gallium nitride

    DOE Patents [OSTI]

    Rubin, M.; Newman, N.; Fu, T.; Ross, J.; Chan, J.

    1997-08-12

    Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5{times}10{sup 11} /cm{sup 3} and hole mobilities of about 500 cm{sup 2} /V-sec, measured at 250 K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al. 9 figs.

  11. AMS-02 electrons and positrons: astrophysical interpretation and Dark Matter constraints

    E-Print Network [OSTI]

    Mattia Di Mauro; Andrea Vittino

    2015-07-30

    We present here a quantitative analysis of the recent AMS-02 data with the purpose of investigating the interplay between astrophysical sources and Dark Matter in their interpretation. First, we show that AMS-02 leptonic measurements are in a remarkably good agreement with the hypothesis that all electrons and positrons are the outcome of primary or secondary astrophysical processes. Then, we add Dark Matter to the picture, in order to establish which are the informations on its annihilation cross section (or lifetime) that can be inferred by fitting AMS-02 data within a scenario in which Dark Matter and astrophysical sources jointly contribute to the different leptonic observables. In particular, by performing a Markov Chain Monte Carlo sampling of the parameters space of the theory, we attempt at characterizing the significance of a possible Dark Matter contribution to the observed data and we derive robust upper limits on the Dark Matter annihilation/decay rate.

  12. AMS-02 electrons and positrons: astrophysical interpretation and Dark Matter constraints

    E-Print Network [OSTI]

    Di Mauro, Mattia

    2015-01-01

    We present here a quantitative analysis of the recent AMS-02 data with the purpose of investigating the interplay between astrophysical sources and Dark Matter in their interpretation. First, we show that AMS-02 leptonic measurements are in a remarkably good agreement with the hypothesis that all electrons and positrons are the outcome of primary or secondary astrophysical processes. Then, we add Dark Matter to the picture, in order to establish which are the informations on its annihilation cross section (or lifetime) that can be inferred by fitting AMS-02 data within a scenario in which Dark Matter and astrophysical sources jointly contribute to the different leptonic observables. In particular, by performing a Markov Chain Monte Carlo sampling of the parameters space of the theory, we attempt at characterizing the significance of a possible Dark Matter contribution to the observed data and we derive robust upper limits on the Dark Matter annihilation/decay rate.

  13. Consumer Electronics

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentrating SolarConstruction Review BasicConsumer-Electronics

  14. Electron Transfer

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear ProfileMultiferroicAward |ElectronFluctuations3 Pierre

  15. Electronic Coupling Dependence of Ultrafast Interfacial Electron...

    Office of Scientific and Technical Information (OSTI)

    Electron Transfer on Nanocrystalline Thin Films and Single Crystal Lian, Tianquan 14 SOLAR ENERGY The long-term goal of the proposed research is to understand electron transfer...

  16. Search for the Standard Model Higgs boson produced in association with a W Boson in the isolated-track charged-lepton channel using the Collider Detector at Fermilab

    SciTech Connect (OSTI)

    Buzatu, Adrian; /McGill U.

    2011-08-01

    The Higgs boson is the only elementary particle predicted by the Standard Model (SM) that has not yet been observed experimentally. If it exists, it explains the spontaneous electroweak symmetry breaking and the origin of mass for gauge bosons and fermions. We test the validity of the SM by performing a search for the associated production of a Higgs boson and a W boson in the channel where the Higgs boson decays to a bottom-antibottom quark pair and the W boson decays to a charged lepton and a neutrino (the WH channel). We study a dataset of proton-antiproton collisions at a centre-of-mass energy {radical}s = 1.96 TeV provided by the Tevatron accelerator, corresponding to an integrated luminosity of 5.7 fb{sup -1}, and recorded using the Collider Detector at Fermilab (CDF).We select events consistent with the signature of exactly one charged lepton (electron or muon), missing transverse energy due to the undetected neutrino (MET) and two collimated streams of particles (jets), at least one of which is required to be identified as originating from a bottom quark. We improve the discrimination of Higgs signal from backgrounds through the use of an artificial neural network. Using a Bayesian statistical inference approach, we set for each hypothetical Higgs boson mass in the range 100-150 GeV/c{sup 2} with 5 GeV/c{sup 2} increments a 95% credibility level (CL) upper limit on the ratio between the Higgs production cross section times branching fraction and the SM prediction. Our main original contributions are the addition of a novel charged lepton reconstruction algorithm with looser requirements (ISOTRK) with respect the electron or muon tight criteria (TIGHT), as well as the introduction of a novel trigger-combination method that allows to maximize the event yield while avoiding trigger correlations and that is used for the ISOTRK category. The ISOTRK candidate is a high-transverse-momentum good-quality track isolated from other activity in the tracking system and not required to match a calorimeter cluster, as for a tight electron candidate, or an energy deposit in the muon detector, as for a tight muon candidate. The ISOTRK category recovers real charged leptons that otherwise would be lost in the non-instrumented regions of the detector. This allows the reconstruction of more W boson candidates, which in turn increases the number of reconstructed WH signal candidate events, and therefore improves the sensitivity of the WH search. For the TIGHT charged lepton categories, we employ charged-lepton-dedicated triggers to improve the rate of WH signal acceptance during data taking. Since there is no ISOTRK-dedicated trigger at CDF, for the ISOTRK charged lepton category we employ three MET-plus-jets-based triggers. For each trigger we first identify the jet selection where the trigger efficiency is flat with respect to jet information (transverse energy and direction of motion in the transverse plane for the two jets in the event) and then we parametrize the trigger efficiency as a function of trigger MET. On an event-by-event basis, for each trigger we compute a trigger efficiency as a function of trigger parametrization, trigger MET, jet information, trigger prescale and information about whether the trigger is defined or not. For the ISOTRK category we combine the three triggers using a novel method, which allows the combination of any number of triggers in order to maximize the event yield while avoiding trigger correlations. On an event-by-event basis, only the trigger with the largest efficiency is used. By avoiding a logical 'OR' between triggers, the loss in the yield of events accepted by the trigger combination is compensated by a smaller and easier-to-compute corresponding systematic uncertainty. The addition of the ISOTRK charged lepton category to the TIGHT category produces an increase of 33% in the WH signal yield and a decrease of 15.5% to 19.0% in the median expected 95% CL cross-section upper limits across the entire studied Higgs mass interval. The improvement in analysis sensitivity is smaller than the i

  17. A Novel Technique to Reconstruct the $Z$ mass in $WZ/ZZ$ Events with Lepton(s), Missing Transverse Energy and Three Jets at CDFII

    SciTech Connect (OSTI)

    Trovato, Marco; Vernieri, Caterina

    2012-01-01

    Observing WZ/ZZ production at the Tevatron in a final state with a lepton, missing transverse energy and jets is extremely difficult because of the low signal rate and the huge background. In an attempt to increase the acceptance we study the sample where three high-energy jets are reconstructed, where about 1/3 of the diboson signal events are expected to end. Rather than choosing the two E{sub T}-leading jets to detect a Z signal, we make use of the information carried by all jets. To qualify the potential of our method, we estimate the probability of observing an inclusive diboson signal at the three standard deviations level (P{sub 3{sigma}}) to be about four times larger than when using the two leading jets only. Aiming at applying the method to the search for the exclusive WZ/ZZ {yields} {ell}{nu}q{bar q} channel in the three jets sample, we analyzed separately the sample with at least one b-tagged jet and the sample with no tags. In WZ/ZZ {yields} {ell}{nu}b{bar b} search, we observe a modest improvement in sensitivity over the option of building the Z-mass from the two leading jets in E{sub T}. Studies for improving the method further are on-going.

  18. Assignment Types UTS LIBRARY

    E-Print Network [OSTI]

    University of Technology, Sydney

    Assignment Types UTS LIBRARY February 2013 Academic Writing Guide Part 2 ­ Assignment Types: This section outlines the basic types of written assignments, providing structural elements and examples. #12;2 II. Assignment Types 1. Essay Writing

  19. CDF note 10582 Search for SM Higgs boson production in association with tt using no lepton final state

    E-Print Network [OSTI]

    Fermilab

    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

  20. Search for Top Squarks in R-Parity-Violating Supersymmetry Using Three or More Leptons and b-Tagged Jets

    E-Print Network [OSTI]

    Apyan, Aram

    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 ...

  1. Measurements of four-lepton production in pp collisions at ?s=8 TeV with the ATLAS Detector

    E-Print Network [OSTI]

    Orlando, Nicola; The ATLAS collaboration

    2015-01-01

    The observation of a new particle consistent with the Standard Model (SM) Higgs boson reported by the ATLAS and CMS Collaborations, is a long-sought achievement of modern physics and represents a new starting point for investigating all the fundamental open questions in particle physics and cosmology. The study of four–lepton production in ATLAS at LHC provides a clean experimental environment for investigating the properties of the Higgs boson, for searching for exotic particles, and for precision tests of the SM gauge symmetry. The inclusive four–lepton line shape measurement (4l, where l = e or ?) in proton-proton collisions at 8 TeV with the ATLAS experiment at LHC, is presented. The measurement is performed in four final states: e+e?e+e? (4e), e+e??+?? (2e2?), ?+??e+e? (2?2e) and ?+ ?? ?+ ?? (4?), where the first lepton pair is defined to be the one with invariant mass closest to the Z boson mass. The analysis considers all four–leptons production modes in the invariant ...

  2. Search for stealth supersymmetry in events with jets, either photons or leptons, and low missing transverse momentum in pp collisions at 8 TeV

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

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

    2015-04-01

    The results of a search for new physics in final states with jets, either photons or leptons, and low missing transverse momentum are reported. The study is based on a sample of proton-proton collisions collected at center-of-mass energy $\\sqrt{s}$ = 8 TeV with the CMS detector in 2012. The integrated luminosity of the sample is 19.7 inverse femtobarns. Many models of new physics predict the production of events with jets, electroweak gauge bosons, and little or no missing transverse momentum. Examples include stealth models of supersymmetry (SUSY), which predict a hidden sector at the electroweak energy scale in which SUSY is approximately conserved. The data are used to search for stealth SUSY signatures in final states with either two photons or an oppositely charged electron and muon. No excess is observed with respect to the standard model expectation, and the results are used to set limits on squark pair production in the stealth SUSY framework.

  3. Search for stealth supersymmetry in events with jets, either photons or leptons, and low missing transverse momentum in pp collisions at 8 TeV

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

    Khachatryan, Vardan; et al.,

    2015-04-01

    The results of a search for new physics in final states with jets, either photons or leptons, and low missing transverse momentum are reported. The study is based on a sample of proton-proton collisions collected at center-of-mass energy $\\sqrt{s}$ = 8 TeV with the CMS detector in 2012. The integrated luminosity of the sample is 19.7 inverse femtobarns. Many models of new physics predict the production of events with jets, electroweak gauge bosons, and little or no missing transverse momentum. Examples include stealth models of supersymmetry (SUSY), which predict a hidden sector at the electroweak energy scale in which SUSYmore »is approximately conserved. The data are used to search for stealth SUSY signatures in final states with either two photons or an oppositely charged electron and muon. No excess is observed with respect to the standard model expectation, and the results are used to set limits on squark pair production in the stealth SUSY framework.« less

  4. Search for Lepton Flavour Violating Decays Tau -> l Ks with the BABAR Detector

    SciTech Connect (OSTI)

    Cenci, Riccardo; /SLAC

    2009-03-20

    We present the search for the lepton flavour violating decay {tau} {yields} lK{sup 0}{sub s} with the BaBar experiment data. This process and many other lepton flavour violating {tau} decays, like {tau} {yields} {mu}{gamma} and {tau} {yields} lll, are one of the most promising channel to search for evidence of new physics. According to the Standard Model and the neutrino mixing parameters, branching fractions are estimated well below 10{sup -14}, but many models of new physics allow for branching fractions values close to the present experimental sensitivity. This analysis is based on a data sample of 469fb{sup -1} collected by BABAR detector at the PEP-II storage ring from 1999 to 2007, equivalent to 431 millions of {tau} pairs. the BABAR experiment, initially designed for studying CP violation in B mesons, has demonstrated to be one of the most suitable environments for studying {tau} decays. The tracking system, the calorimeter and the particle identification of BABAR, together with the knowledge of the {tau} initial energy, allow an extremely powerful rejection of background events that, for this analysis, is better than 10{sup -9}. Being {tau} {yields} lK{sup 0}{sub s} a decay mode without neutrinos, the signal {tau} decay can be fully reconstructed. Kinematical constraints are used in a fit that provides a decay tree reconstruction with a high resolution. For this analysis MC simulated events play a decisive role for estimating the signal efficiency and study the residual background. High statistics MC sample are produced simulating detector conditions for different periods of data collection, in order to reduce any discrepancies with the data. When discrepancies can not be removed, we perform studies to compute a correction factor or an estimation of systematic errors that need to be included in the final measurement. A significant improvement of the current result can be reached only with a higher statistics and, therefore, with a new collider providing a luminosity from 10 to 100 times more than PEP-II. A new detector, with improved performance and able to collect data in a high background environment, is also requested to fully exploit the capability of such amount of data. In fact, only keeping the efficiency and the background as similar as possible to present ones, we will be able to scale almost linearly the estimated upper limit according to the luminosity. The strong potential of improvement for the search of lepton flavour violation {tau} decays makes the building of such a machine highly desirable.

  5. Constraints on Lepton Asymmetry from Nucleosynthesis in a Linearly Coasting Cosmology

    E-Print Network [OSTI]

    Parminder Singh; Daksh Lohiya

    2015-05-30

    We study the effect of neutrino degeneracy on primordial nucleosynthesis in a universe in which the cosmological scale factor evolves linearly with time. The degeneracy parameter of electron type neutrinos ($\\xi_e$) determines the $n/p$ (neutron to proton) ratio, which in turn determines the abundance of $^4$He in a manner quite distinct from the Standard Scenario. The observed abundances of $^4$He, $\\mathrm{Y}_P$=0.254$\\pm$0.003, and the minimum metallicity that is essential for fragmentation and cooling processes in star forming prestellar gas clouds (Z = Z$_{cr}$ = 10$^{-6}$Z$_\\odot$), constrain the baryon to photon ratio, $\\eta_B$=(3.927$\\pm$0.292)10$^{-9}$, corresponding to a baryonic matter density, $\\Omega_B$=0.263$\\pm$ 0.026 and $\\xi_e$=-2.165$\\pm$0.171. This closes the dynamic mass estimates of matter in the universe by baryons alone. Useful byproducts are the threshold X(CNO) abundances required to trigger the CNO cycle in the observed low metallicity stars in the universe.

  6. Electromagnetic Heavy Lepton Pair Production in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Sengul, M Y; Mercan, O; Karakus, N G

    2015-01-01

    We calculate the cross sections of electromagnetic productions of muon and tauon pair productions from the ultra-relativistic heavy ion collisions. Since the Compton wavelengths of muon and tauon are comparable to the radius of the colliding ions, nuclear form factors play important roles for calculating the cross sections. Recent measurement [1] indicates that the neutrons are differently distributed from the protons therefore this affects the cross section of the heavy lepton pair production. In order to see the effects of the neutron distributions in the nucleus, we used analytical expression of the Fourier transforms of the Wood-Saxon distribution. Cross section calculations show that Wood-Saxon distribution function is more sensitive to the parameter R compare to the parameter a.

  7. Multi-wavelength constraints on cosmic-ray leptons in the Galaxy

    E-Print Network [OSTI]

    Orlando, E; Moskalenko, I V; Dickinson, C; Digel, S; Jaffe, T R; Jóhannesson, G; Leahy, J P; Porter, T A; Vidal, M

    2015-01-01

    Cosmic rays (CRs) interact with the gas, the radiation field and the magnetic field in the Milky Way, producing diffuse emission from radio to gamma rays. Observations of this diffuse emission and comparison with detailed predictions are powerful tools to unveil the CR properties and to study CR propagation. We present various GALPROP CR propagation scenarios based on current CR measurements. The predicted synchrotron emission is compared to radio surveys, and synchrotron temperature maps from WMAP and Planck, while the predicted interstellar gamma-ray emission is compared to Fermi-LAT observations. We show how multi-wavelength observations of the Galactic diffuse emission can be used to help constrain the CR lepton spectrum and propagation. Finally we discuss how radio and microwave data could be used in understanding the diffuse Galactic gamma-ray emission observed with Fermi-LAT, especially at low energies.

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

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

    Aad, G.

    2015-04-21

    Results of a search for H ? ?? 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 fb–1 and 20.3 fb–1 at centre-of-mass energies of ?s=7 TeV and ?s=8 TeV respectively. All combinations of leptonic (? ? ???¯ with ? = e, ?) and hadronic (? ? hadrons ?) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standardmore »deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalized to the Standard Model expectation, of ? = 1.43–0.37+0.43 is consistent with the predicted Yukawa coupling strength in the Standard Model.« less

  9. The tau leptons theory and experimental data: Monte Carlo, fits, software and systematic errors

    E-Print Network [OSTI]

    Zbigniew Was

    2014-12-09

    Status of tau lepton decay Monte Carlo generator TAUOLA is reviewed. Recent efforts on development of new hadronic currents are presented. Multitude new channels for anomalous tau decay modes and parametrization based on defaults used by BaBar collaboration are introduced. Also parametrization based on theoretical considerations are presented as an alternative. Lesson from comparison and fits to the BaBar and Belle data is recalled. It was found that as in the past, in particular at a time of comparisons with CLEO and ALEPH data, proper fitting, to as detailed as possible representation of the experimental data, is essential for appropriate developments of models of tau decays. In the later part of the presentation, use of the TAUOLA program for phenomenology of W,Z,H decays at LHC is adressed. Some new results, relevant for QED bremsstrahlung in such decays are presented as well.

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

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

    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

    2011-08-09

    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.

  11. Precision measurement of the top-quark mass in lepton$+$jets final states

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

    Abazov, Victor Mukhamedovich

    2015-06-04

    We measure the mass of the top quark in lepton þ jets final states using the full sample of pp¯ collision data collected by the D0 experiment in Run II of the Fermilab Tevatron Collider at ffiffi s p ¼ 1.96 TeV, corresponding to 9.7 fb-1 of integrated luminosity. We also use a matrix element technique that calculates the probabilities for each event to result from t¯t production or background. Furthermore, the overall jet energy scale is constrained in situ by the mass of the W boson. We measure mt ¼ 174.98 0.76 GeV. This constitutes the most precise singlemore »measurement of the top-quark mass.« less

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

    E-Print Network [OSTI]

    Giuseppe Bozzi; Luca Citelli; Alessandro Vicini

    2015-05-22

    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.

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

    E-Print Network [OSTI]

    Bozzi, Giuseppe; Vicini, Alessandro

    2015-01-01

    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.

  14. The Leptonic CP Phase from Muon Decay at Rest with Two Detectors

    E-Print Network [OSTI]

    Emilio Ciuffoli; Jarah Evslin; Xinmin Zhang

    2014-03-10

    We propose a novel experimental setup for the determination of the leptonic CP-violating phase delta using the decay at rest (DAR) of mu+ from a single source located at distances of 10 and 30 km from two 20 kton organic liquid scintillator detectors. The mu+ are created by bombarding a target with a 9 mA beam of 800 MeV protons. With this proposal delta can be determined with a precision of about 20 (15) degrees in 6 (12) years. In contrast with the DAEdALUS project, only a single source is required and it runs with a duty factor of 100 percent. Therefore 9 mA is the maximum instanteous current, greatly reducing both the technological challenges and the costs.

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

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

    Abazov, Victor Mukhamedovich

    2011-08-09

    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, wemore »measure a top-quark mass of mt = 174.94 ± 1.49 GeV for a total integrated luminosity of 3.6 fb-1.« less

  16. A Typed Operational Semantics for Type Theory 

    E-Print Network [OSTI]

    Goguen, Healfdene

    Untyped reduction provides a natural operational semantics for type theory. Normalization results say that such a semantics is sound. However, this reduction does not take type information into account and gives no information ...

  17. PEPPo: Using a Polarized Electron Beam to Produce Polarized Positrons

    SciTech Connect (OSTI)

    Adeyemi, Adeleke H.

    2015-09-01

    Polarized positron beams have been identified as either an essential or a significant ingredient for the experimental program of both the present and next generation of lepton accelerators (JLab, Super KEK B, ILC, CLIC). An experiment demonstrating a new method for producing polarized positrons has been performed at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e-/e+ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high Z conversion target. PEPPo demonstrated the effective transfer of spin-polarization of an 8.2 MeV/c polarized (P~85%) electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for producing either high energy or thermal polarized positron beams using a relatively low polarized electron beam energy (~10MeV) .This presentation will describe the PEPPo concept, the motivations of the experiment and high positron polarization achieved.

  18. Optically pulsed electron accelerator

    DOE Patents [OSTI]

    Fraser, J.S.; Sheffield, R.L.

    1985-05-20

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  19. Optically pulsed electron accelerator

    DOE Patents [OSTI]

    Fraser, John S. (Los Alamos, NM); Sheffield, Richard L. (Los Alamos, NM)

    1987-01-01

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  20. Measurement of the Bottom contribution to non-photonic electron production in $p+p$ collisions at $\\sqrt{s} $=200 GeV

    E-Print Network [OSTI]

    STAR Collaboration; M. M. Aggarwal

    2010-11-25

    The contribution of $B$ meson decays to non-photonic electrons, which are mainly produced by the semi-leptonic decays of heavy flavor mesons, in $p+p$ collisions at $\\sqrt{s} =$ 200 GeV has been measured using azimuthal correlations between non-photonic electrons and hadrons. The extracted $B$ decay contribution is approximately 50% at a transverse momentum of $p_{T} \\geq 5$ GeV/$c$. These measurements constrain the nuclear modification factor for electrons from $B$ and $D$ meson decays. The result indicates that $B$ meson production in heavy ion collisions is also suppressed at high $p_{T}$.

  1. Blazar synchrotron emission of instantaneously power-law injected electrons under linear synchrotron, non-linear SSC, and combined synchrotron-SSC cooling

    E-Print Network [OSTI]

    Zacharias, M

    2010-01-01

    The broadband SEDs of blazars show two distinct components which in leptonic models are associated with synchrotron and SSC emission of highly relativistic electrons. In some sources the SSC component dominates the synchrotron peak by one or more orders of magnitude implying that the electrons mainly cool by inverse Compton collisions with their self-made synchrotron photons. Therefore, the linear synchrotron loss of electrons, which is normally invoked in emission models, has to be replaced by a nonlinear loss rate depending on an energy integral of the electron distribution. This modified electron cooling changes significantly the emerging radiation spectra. It is the purpose of this work to apply this new cooling scenario to relativistic power-law distributed electrons, which are injected instantaneously into the jet. We will first solve the differential equation of the volume-averaged differential number density of the electrons, and then discuss their temporal evolution. Since any non-linear cooling will...

  2. Types of Commissioning

    Broader source: Energy.gov [DOE]

    Several commissioning types exist to address the specific needs of equipment and systems across both new and existing buildings. The following commissioning types provide a good overview.

  3. Postdoc Appointment Types

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

    Appointment Types Postdoc Appointment Types Most postdocs will be offered a postdoctoral research associate appointment. Each year, approximately 30 Postdoctoral Fellow...

  4. 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]

    Taylor, Frank E.

    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 ...

  5. Searches for supersymmetry with the ATLAS detector using final states with two leptons and missing transverse momentum in ?s = 7 TeV proton–proton collisions

    E-Print Network [OSTI]

    Taylor, Frank E.

    Results of three searches are presented for the production of supersymmetric particles decaying into final states with missing transverse momentum and exactly two isolated leptons, e or ?. The analysis uses a data sample ...

  6. Search for physics beyond the standard model in events with two leptons, jets, and missing transverse momentum in pp collisions at ?s = 8 TeV

    E-Print Network [OSTI]

    Apyan, Aram

    A search is presented for physics beyond the standard model in final states with two opposite-sign same-flavor leptons, jets, and missing transverse momentum. The data sample corresponds to an integrated luminosity of 19.4 ...

  7. Search for stealth supersymmetry in events with jets, either photons or leptons, and low missing transverse momentum in pp collisions at 8 TeV

    E-Print Network [OSTI]

    Apyan, Aram

    The results of a search for new physics in final states with jets, either photons or leptons, and low missing transverse momentum are reported. The study is based on a sample of proton–proton collisions collected at a ...

  8. Search for TeV-scale gravity signatures in final states with leptons and jets with the ATLAS detector at ?s = 7 TeV

    E-Print Network [OSTI]

    Taylor, Frank E.

    The production of events with multiple high transverse momentum particles including charged leptons and jets is measured, using 1.04 fb[superscript ?1] of proton–proton collision data recorded by the ATLAS detector during ...

  9. 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]

    Gomez-Ceballos, Guillelmo

    We present an analysis of top-antitop quark production and decay into a tau lepton, tau neutrino, and bottom quark using data from 9??fb[superscript ?1] of integrated luminosity at the Collider Detector at Fermilab. Dilepton ...

  10. Chapter 9: Electronics

    E-Print Network [OSTI]

    Spieler, Helmuth G

    2008-01-01

    R. Armstrong Contents Electronics 9.1 Introduction 9.2measurements 9.11 Digital electronics 9.11.1 Logic elementsProblems page 1 vii Electronics This chapter was contributed

  11. Measurement of the lepton charge asymmetry in inclusive $W$ production in pp collisions at sqrt(s) = 7 TeV

    SciTech Connect (OSTI)

    Chatrchyan, V.; et al.,

    2011-04-01

    A measurement of the lepton charge asymmetry in inclusive pp to WX production at sqrt(s)= 7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns. This high precision measurement of the lepton charge asymmetry, performed in both the W to e nu and W to mu nu channels, provides new insights into parton distribution functions.

  12. The Effects of Fourth Generation on the Total Branching Ratio and the Lepton Polarization in $?_b \\rar ?\\ell^+ \\ell^-$ decay

    E-Print Network [OSTI]

    V. Bashiry; K. Azizi

    2007-07-09

    This study investigates the influence of the fourth generation quarks on the total branching ratio and the single lepton polarizations in \\Lambda_b --> \\Lambda \\ell^+ \\ell^- decay. Taking $|V_{t's}V_{t'b}| {0.01-0.03} with phase just below $90^\\circ$, which is consistent with the b\\to s\\ell^+\\ell^- rate and the B_s mixing parameter \\Delta m_{B_s}, we obtain that the total branching ratio and the single lepton(\\mu, \\tau) polarizations are quite sensitive to the existence of fourth generation. It can serve as a good tool to search for new physics effects, precisely, to search for the fourth generation quarks(t', b').

  13. Search for lepton--flavour--violating $H\\to\\mu\\tau$ decays of the Higgs boson with the ATLAS detector

    E-Print Network [OSTI]

    ,; ATLAS Collaboration

    2015-01-01

    A direct search for lepton--flavour--violating (LFV) $H\\to\\mu\\tau$ decays of the recently discovered Higgs boson with the ATLAS detector at the LHC is presented. The analysis is performed in the $H\\to\\mu\\tau_{\\mathrm{had}}$ channel, where $\\tau_{\\mathrm{had}}$ is a hadronically decaying $\\tau$--lepton. The search is based on the data sample of proton--proton collisions collected by the ATLAS experiment corresponding to an integrated luminosity of 20.3~fb$^{-1}$ at a centre--of--mass energy of $\\sqrt{s}=8$ TeV. No statistically significant excess of data over the predicted background is observed. The observed (expected) 95% confidence--level upper limit on the branching fraction, Br($H\\to\\mu\\tau$), is 1.85% (1.24%).

  14. The two-loop helicity amplitudes for $q \\bar q' \\to V_1 V_2 \\to 4~\\mathrm{leptons}$

    E-Print Network [OSTI]

    Thomas Gehrmann; Andreas von Manteuffel; Lorenzo Tancredi

    2015-09-11

    We compute the two-loop massless QCD corrections to the helicity amplitudes for the production of two massive vector bosons in quark-antiquark annihilation, allowing for an arbitrary virtuality of the vector bosons: $q \\bar q' \\to V_1V_2$. Combining with the leptonic decay currents, we obtain the full two-loop QCD description of the corresponding electroweak four-lepton production processes. The calculation is performed by projecting the two-loop diagrams onto an appropriate basis of Lorentz structures. All two-loop Feynman integrals are reduced to a basis of master integrals, which are then computed using the differential equations method and optimised for numerical performance. We provide a public C++ code which allows for fast and precise numerical evaluations of the amplitudes.

  15. Study of two- and three-meson decay modes of tau-lepton with Monte Carlo generator TAUOLA

    E-Print Network [OSTI]

    Shekhovtsova, Olga

    2015-01-01

    The study of the $\\tau$-lepton decays into hadrons has contributed to a better understanding of non-perturbative QCD and light-quark meson spectroscopy, as well as to the search of new physics beyond the Standard Model. The two- and three-meson decay modes, considering only those permitted by the Standard Model, are the predominant decays and together with the one-pion mode compose more than $85\\%$ of the hadronic $\\tau$-lepton decay width. In this note we review the theoretical results for these modes implemented in the Monte Carlo event generator TAUOLA and present at the same time a comparison with the Belle Collaboration data for the two-pion decay mode and the BaBar preliminary data for the three-pion decay mode as well for the decay mode into two-kaon and one-pion.

  16. Pseudopotential for the electron-electron interaction

    E-Print Network [OSTI]

    Lloyd-Williams, J H; Conduit, G J

    2015-01-01

    We propose a pseudopotential for the electron-electron Coulomb interaction to improve the efficiency of many-body electronic structure calculations. The pseudopotential accurately replicates the scattering properties of the Coulomb interaction, and recovers the analytical solution for two electrons in a parabolic trap. A case study for the homogeneous electron gas using the diffusion Monte Carlo and configuration interaction methods recovers highly accurate values for the ground state energy, and the smoother potential reduces the computational cost by a factor of ~30. Finally, we demonstrate the use of the pseudopotential to study isolated lithium and beryllium atoms.

  17. Controlling Graphene's Electronic Structure

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

    Controlling Graphene's Electronic Structure Print Wednesday, 25 April 2007 00:00 Graphene, because of its unusual electron properties, reduced dimensionality, and scale, has...

  18. DELAYED ONSET OF HIGH-ENERGY EMISSIONS IN LEPTONIC AND HADRONIC MODELS OF GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Asano, Katsuaki [Interactive Research Center of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan); Meszaros, Peter, E-mail: asano@phys.titech.ac.jp, E-mail: nnp@astro.psu.edu [Department of Astronomy and Astrophysics, Department of Physics, Center for Particle and Gravitational Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2012-10-01

    The temporal-spectral evolution of the prompt emission of gamma-ray bursts is simulated numerically for both leptonic and hadronic models. For weak enough magnetic fields, leptonic models can reproduce the few seconds delay of the onset of GeV photon emission observed by Fermi-LAT, due to the slow growth of the target photon field for inverse Compton scattering. For stronger magnetic fields, the GeV delay can be explained with hadronic models, due to the long acceleration timescale of protons and the continuous photopion production after the end of the particle injection. While the FWHMs of the MeV and GeV light curves are almost the same in one-zone leptonic models, the FWHMs of the 1-30 GeV light curves in hadronic models are significantly wider than those of the 0.1-1 MeV light curves. The amount of the GeV delay depends on the importance of the Klein-Nishina effect in both the leptonic and hadronic models. In our examples of hadronic models the energies of the escaped neutrons are comparable to the gamma-ray energy, although their contribution to the ultra high-energy cosmic rays is still subdominant. The resulting neutrino spectra are hard enough to avoid the flux limit constraint from IceCube. The delay of the neutrino emission onset is up to several times longer than the corresponding delay of the GeV photon emission onset. The quantitative differences in the light curves for various models may be further tested with future atmospheric Cerenkov telescopes whose effective area is larger than that of Fermi-LAT, such as CTA.

  19. Inclusive tau lepton hadronic decay in vector and axial-vector channels within dispersive approach to QCD

    E-Print Network [OSTI]

    Nesterenko, A V

    2015-01-01

    The dispersive approach to QCD, which properly embodies the intrinsically nonperturbative constraints originating in the kinematic restrictions on relevant physical processes and extends the applicability range of perturbation theory towards the infrared domain, is briefly overviewed. The study of OPAL (update 2012) and ALEPH (update 2014) experimental data on inclusive tau lepton hadronic decay in vector and axial-vector channels within dispersive approach is presented.

  20. Types of Lights Types of Lights

    E-Print Network [OSTI]

    1 Types of Lights Types of Lights q So far we have studied point lights ­ Radiate in all direc7ons q Other lights ­ Direc7onal lights (posi7on-independent) ­ Spotlights #12;2 Direc1onal Lights q Shine in a single, uniform direc7on q All rays

  1. The Calibration of the PEPPo Polarimeter for Electrons and Positrons

    SciTech Connect (OSTI)

    Adeyemi, Adeleke Hakeem [Hampton University, Hampton, VA (United States); Voutier, Eric J-.M. [Laboratoire de Physique Subatomique et Cosmologie, Grenoble (France)

    2013-06-01

    The PEPPo (Polarized Electrons for Polarized Positrons) experiment at Jefferson Laboratory investigated the polarization transfer from longitudinally polarized electrons to longitudinally polarized positrons, with the aim of developing this technology for a low energy (~MeV) polarized positron source. Polarization of the positrons was measured by means of a Compton transmission polarimeter where incoming positrons transfer their polarization into circularly polarized photons that were subsequently analyzed by a thick polarized iron target. The measurement of the transmitted photon flux with respect to the orientation of the target polarization (+-) or the helicity (+-) of the incoming leptons provided the measurement of their polarization. Similar measurements with a known electron beam were also performed for calibration purposes. This presentation will describe the apparatus and calibrations performed at the injector at the Jefferson Laboratory to measure positron polarization in the momentum range 3.2-6.2 MeV/c, specifically to quantify the positron analyzing power from electron experimental data measured over a comparable momentum range.

  2. Electron Surfing Acceleration in Magnetic Reconnection

    E-Print Network [OSTI]

    Masahiro Hoshino

    2005-07-22

    We discuss that energetic electrons are generated near the X-type magnetic reconnection region due to a surfing acceleration mechanism. In a thin plasma sheet, the polarization electric fields pointing towards the neutral sheet are induced around the boundary between the lobe and plasma sheet in association with the Hall electric current. By using a particle-in-cell simulation, we demonstrate that the polarization electric fields are strongly enhanced in an externally driven reconnection system, and some electrons can be trapped by the electrostatic potential well of the polarization field. During the trapping phase, the electrons can gain their energies from the convection/inductive reconnection electric fields. We discuss that relativistic electrons with MeV energies are quickly generated in and around the X-type neutral region by utilizing the surfing acceleration.

  3. Search for Lepton-Number Violating Processes in B+ to h- l+ l+ Decays

    SciTech Connect (OSTI)

    Lees, J.P.

    2012-05-17

    We have searched for the lepton-number violating processes B{sup +} {yields} h{sup -}{ell}{sup +}{ell}{sup +} with h{sup -} = K{sup -}/{pi}{sup -} and {ell}{sup +} = e{sup +}/{mu}{sup +}, using a sample of 471 {+-} 3 million B{bar B} events collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. We find no evidence for these decays and place 90% confidence level upper limits on their branching fractions B (B{sup +} {yields} {pi}{sup -}e{sup +}e{sup +}) < 2.3 x 10{sup -8}, {Beta}(B{sup +} {yields} K{sup -}e{sup +}e{sup +}) < 3.0 x 10{sup -8}, {Beta}(B{sup +} {yields} {pi}{sup -}{mu}{sup +}{mu}{sup +}) < 10.7 x 10{sup -8}, and {Beta}(B{sup +} {yields} K{sup -}{mu}{sup +}{mu}{sup +}) < 6.7 x 10{sup -8}.

  4. Search for Rare Multi-Pion Decays of the Tau Lepton Using the BABAR Detector

    SciTech Connect (OSTI)

    Ter-Antonyan, Ruben

    2007-09-18

    A search for the decay of the {tau} lepton to rare multi-pion final states is performed using the BABAR detector at the PEP-II asymmetric-energy e+e- collider. The analysis uses 232 fb-1 of data at center-of-mass energies on or near the {Upsilon}(4S) resonance. In the search for the {tau}- {yields} 3{pi}-2{pi}+2{pi}{sup 0}{nu}{sub {tau}} decay, we observe 10 events with an expected background of 6.5{sup +2.0}{sub -1.4} events. In the absence of a signal, we calculate the decay branching ratio upper limit {beta}({tau}- {yields} 3{pi}-2{pi}+2{pi}{sup 0}{nu}{sub {tau}}) < 3.4 x 10{sup -6} at the 90% confidence level. This is more than a factor of 30 improvement over the previously established limit. In addition, we search for the exclusive decay mode {tau}- {yields} 2{omega}{pi}-{nu}{sub {tau}} with the further decay of {omega} {yields} {pi}-{pi}+{pi}{sup 0}. We observe 1 event, expecting 0.4{sup +1.0}{sub -0.4} background events, and calculate the upper limit {beta}{tau}-{yields} 2{omega}{pi}-{nu}{sub {tau}} < 5.4 x 10{sup -7} at the 90% confidence level. This is the first upper limit for this mode.

  5. Time-space symmetry as a solution to the mass hierarchy of charged lepton generations

    E-Print Network [OSTI]

    Vo Van Thuan

    2015-07-27

    Based on an extended time-space symmetry, a cylindrical model of gravitational geometrical dynamics with two time-like extra-dimensions leads to a microscopic geodesic description of the curved space-time. Due to interaction of a Higgs-like cosmological potential with individual space-time fluctuations, the original time-space symmetry is spontaneously broken, inducing a strong time-like curvature and a weak space-like deviation curve. As a result, the basic Klein-Gordon-Fock equation of a free massive elementary particle was derived, which implies a duality between the quantum mechanics equation and a microscopic geodesic description in the frame of general relativity. Consequently, Heisenberg inequalities are determined explicitly by the space-time curvatures. Moreover, extending curvatures to higher time-like dimensional hyper-spherical surfaces than one of the basic common cylindrical configuration, we found reasonable mass ratios of all charged leptons and succeeded to fix the number of their generations to be three. Following to concepts of the standard cosmological model, a possible experimental verification of mass ratio variation is proposed.

  6. Time-space symmetry as a solution to the mass hierarchy of charged lepton generations

    E-Print Network [OSTI]

    Van Thuan, Vo

    2015-01-01

    Based on an extended time-space symmetry, a cylindrical model of gravitational geometrical dynamics with two time-like extra-dimensions leads to a microscopic geodesic description of the curved space-time. Due to interaction of a Higgs-like cosmological potential with individual space-time fluctuations, the original time-space symmetry is spontaneously broken, inducing a strong time-like curvature and a weak space-like deviation curve. As a result, the basic Klein-Gordon-Fock equation of a free massive elementary particle was derived, which implies a duality between the quantum mechanics equation and a microscopic geodesic description in the frame of general relativity. Consequently, Heisenberg inequalities are determined explicitly by the space-time curvatures. Moreover, extending curvatures to higher time-like dimensional hyper-spherical surfaces than one of the basic common cylindrical configuration, we found reasonable mass ratios of all charged leptons and succeeded to fix the number of their generations...

  7. Lepton number violating processes mediated by Majorana neutrinos at hadron colliders

    SciTech Connect (OSTI)

    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)

    2009-10-01

    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.

  8. Limits on the Higgs boson lifetime and width from its decay to four charged leptons

    E-Print Network [OSTI]

    CMS Collaboration

    2015-07-23

    Constraints on the lifetime and width of the Higgs boson are obtained from H to ZZ to 4 lepton events using data recorded by the CMS experiment during the LHC run 1 with an integrated luminosity of 5.1 and 19.7 inverse femtobarns at a center-of-mass energy of 7 and 8 TeV, respectively. The measurement of the Higgs boson lifetime is derived from its flight distance in the CMS detector with an upper bound of tau[H] 3.5E-9 MeV. The measurement of the width is obtained from an off-shell production technique, generalized to include anomalous couplings of the Higgs boson to two electroweak bosons. From this measurement, a joint constraint is set on the Higgs boson width and a parameter f[LQ] that expresses an anomalous coupling contribution as an on-shell cross-section fraction. The limit on the Higgs boson width is Gamma[H] Higgs boson width.

  9. Discovery and Characterization of a Higgs boson using four-lepton events from the CMS experiment

    E-Print Network [OSTI]

    AUTHOR|(SzGeCERN)678846

    2015-01-01

    A new particle decaying to a pair of vector bosons was discovered in 2012 by the ATLAS and CMS experiments at the Large Hadron Collider. In the wake of this discovery a rush of measurements was made to characterize this particle. The four-lepton final state has been instrumental in both the discovery and characterization of this new particle. With only about 20 events seen in the resonance peak at 125GeV the CMS experiment has been able to make considerable progress in characterizing the Higgs-like boson using the wealth of information in this final state in concert with other decay modes. In addition to the search for this new boson we present three recent results in the study of the Higgs-like boson properties: studies of the production mode, total width, and spin-parity quantum numbers. First we present the search for this new resonance using the H to ZZ to 4l decay channel. Then we discuss the production mode measurement using this final state. Next, we present two results that provided breakthroughs in t...

  10. Quark-Lepton Complementarity Predictions for $\\theta_{23}^{pmns}$ and CP Violation

    E-Print Network [OSTI]

    Sharma, Gazal

    2015-01-01

    In the light of recent experimental results on $\\theta_{13}^{pmns}$, we re-investigate the complementarity between the quark and lepton mixing matrices and obtain predictions with updated global data fits. This paper is motivated by our previous work where in a QLC model we predicted the value for $\\theta_{13}^{pmns}=(9{^{+1}_{-2}})^\\circ$, which was found to be in strong agreement with the experimental results. In the QLC model the non-trivial correlation between CKM and PMNS mixing matrices is given by a correlation matrix ($V_{c}$). We do numerical simulation and estimate the texture of the $V_{c}$ and in our findings we get a small deviation from the Tri-Bi-Maximal (TBM) texture and a large from the Bi-Maximal one, which is consistent with the work already reported in literature. In the further investigation we obtain quite constrained limits for $sin^2{\\theta_{23}^{pmns}}= 0.4235_{-0.0043}^{+0.0032}$ that is narrower to the existing ones. We also obtain the constrained limits for the three CP violating p...

  11. ELECTRONIC CHARTS INTRODUCTION

    E-Print Network [OSTI]

    New Hampshire, University of

    199 CHAPTER 14 ELECTRONIC CHARTS INTRODUCTION 1400. The Importance of Electronic Charts Since. Electronic charts automate the process of integrating real-time positions with the chart display and allow is expected to take and plot a fix every three minutes. An electronic chart system can do it once per second

  12. Theoretical studies of electronically excited states

    SciTech Connect (OSTI)

    Besley, Nicholas A.

    2014-10-06

    Time-dependent density functional theory is the most widely used quantum chemical method for studying molecules in electronically excited states. However, excited states can also be computed within Kohn-Sham density functional theory by exploiting methods that converge the self-consistent field equations to give excited state solutions. The usefulness of single reference self-consistent field based approaches for studying excited states is demonstrated by considering the calculation of several types of spectroscopy including the infrared spectroscopy of molecules in an electronically excited state, the rovibrational spectrum of the NO-Ar complex, core electron binding energies and the emission spectroscopy of BODIPY in water.

  13. Types of Reuse

    Broader source: Energy.gov [DOE]

    The following provides greater detail regarding the types of reuse pursued for LM sites. It should be noted that many actual reuses combine several types of the uses listed below.

  14. Notice Type: Presolicitation

    E-Print Network [OSTI]

    components NAICS Code: 334 -- Computer and Electronic Product Manufacturing/334417 -- Electronic Connector Manufacturing Synopsis: Added: Aug 14, 2014 4:06 pm The Naval Research Laboratory has a requirement for 576 each MM4S-13420 MM4S Female 50-OHM Termination. (Microsoft IE required). Additional specifications

  15. Notice Type: Presolicitation

    E-Print Network [OSTI]

    components NAICS Code: 334 -- Computer and Electronic Product Manufacturing/334419 -- Other Electronic Component Manufacturing Synopsis: Added: Sep 03, 2014 2:53 pm The Naval Research Laboratory has a requirement for 1 each 6-18 GHz Activity Detection Module P/N: N13-4167. (Microsoft IE required). Additional

  16. Notice Type: Presolicitation

    E-Print Network [OSTI]

    : 334 -- Computer and Electronic Product Manufacturing/334419 -- Other Electronic Component Manufacturing Synopsis: Added: Jul 02, 2014 1:54 pm The Naval Research Laboratory has a requirement for 1 each No: 12072-2-RFB. (Microsoft IE required). Additional specifications and opening and closing dates

  17. Study of electron-positron interactions

    SciTech Connect (OSTI)

    Abashian, A.; Gotow, K.; Philonen, L.

    1990-09-15

    For the past seven years, this group has been interested in the study of tests of the Standard Model of Electroweak interactions. The program has centered about the AMY experiment which examines the nature of the final state products in electron-positron collisions in the center of mass energy range near 60 GeV. Results of these measurements have shown a remarkable consistency with the predictions of the minimal model of 3 quark and lepton generations and single charged and neutral intermediate bosons. No new particles or excited states have been observed nor has any evidence for departures in cross sections or angular asymmetries from expectations been observed. These conclusions have been even more firmly established by the higher energy results from the LEP and SLC colliders at center of mass energies of about 90 GeV. Our focus is shifting to the neutrino as a probe to electroweak interactions. The relative merit of attempting to observe neutrinos from point sources versus observing neutrinos generally is not easy to predict. The improved ability to interpret is offset by the probably episodic nature of the emission and irreproducibility of the results. In this phase of development, it is best to be sensitive to both sources of neutrinos. As a second phase of our program at Virginia Tech, we are studying the feasibility of detecting cosmic ray neutrinos in a proposed experiment which we have called NOVA. the results of the test setup will be instrumental in developing an optimum design. A third program we are involved in is the MEGA experiment at Los Alamos, an experiment to place a limit on the rate of muon decay to electron plus photon which is forbidden by the Standard Model.

  18. Direct gap photoluminescence of n-type tensile-strained Ge-on-Si

    E-Print Network [OSTI]

    Sun, Xiaochen

    Room temperature direct gap photoluminescence (PL) was observed from n-type tensile-strained epitaxial Ge-on-Si. The PL intensity increases with n-type doping due to a higher electron population in the direct ? valley as ...

  19. RHIC electron lenses upgrades

    SciTech Connect (OSTI)

    Gu, X.; Altinbas, Z.; Bruno, D.; Binello, S.; Costanzo, M.; Drees, A.; Fischer, W.; Gassner, D. M.; Hock, J.; Hock, K.; Harvey, M.; Luo, Y.; Marusic, A.; Mi, C.; Mernick, K.; Minty, M.; Michnoff, R.; Miller, T. A.; Pikin, A. I.; Robert-Demolaize, G.; Samms, T.; Shrey, T. C.; Schoefer, V.; Tan, Y.; Than, R.; Thieberger, P.; White, S. M.

    2015-05-03

    In the Relativistic Heavy Ion Collider (RHIC) 100 GeV polarized proton run in 2015, two electron lenses were used to partially compensate for the head-on beam-beam effect for the first time. Here, we describe the design of the current electron lens, detailing the hardware modifications made after the 2014 commissioning run with heavy ions. A new electron gun with 15-mm diameter cathode is characterized. The electron beam transverse profile was measured using a YAG screen and fitted with a Gaussian distribution. During operation, the overlap of the electron and proton beams was achieved using the electron backscattering detector in conjunction with an automated orbit control program.

  20. Electronic field permeameter

    DOE Patents [OSTI]

    Chandler, Mark A. (Madison, WI); Goggin, David J. (Austin, TX); Horne, Patrick J. (Austin, TX); Kocurek, Gary G. (Roundrock, TX); Lake, Larry W. (Austin, TX)

    1989-01-01

    For making rapid, non-destructive permeability measurements in the field, a portable minipermeameter of the kind having a manually-operated gas injection tip is provided with a microcomputer system which operates a flow controller to precisely regulate gas flow rate to a test sample, and reads a pressure sensor which senses the pressure across the test sample. The microcomputer system automatically turns on the gas supply at the start of each measurement, senses when a steady-state is reached, collects and records pressure and flow rate data, and shuts off the gas supply immediately after the measurement is completed. Preferably temperature is also sensed to correct for changes in gas viscosity. The microcomputer system may also provide automatic zero-point adjustment, sensor calibration, over-range sensing, and may select controllers, sensors, and set-points for obtaining the most precise measurements. Electronic sensors may provide increased accuracy and precision. Preferably one microcomputer is used for sensing instrument control and data collection, and a second microcomputer is used which is dedicated to recording and processing the data, selecting the sensors and set-points for obtaining the most precise measurements, and instructing the user how to set-up and operate the minipermeameter. To provide mass data collection and user-friendly operation, the second microcomputer is preferably a lap-type portable microcomputer having a non-volatile or battery-backed CMOS memory.

  1. Identification and energy calibration of hadronically decaying tau leptons with the ATLAS experiment in pp collisions at ?s = 8 TeV

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

    Aad, G.

    2015-07-02

    This study describes the trigger and offline reconstruction, identification and energy calibration algorithms for hadronic decays of tau leptons employed for the data collected from pp collisions in 2012 with the ATLAS detector at the LHC center-of-mass energy ?s=8 TeV. The performance of these algorithms is measured in most cases with Z decays to tau leptons using the full 2012 dataset, corresponding to an integrated luminosity of 20.3 fb–1. An uncertainty on the offline reconstructed tau energy scale of 2–4%, depending on transverse energy and pseudorapidity, is achieved using two independent methods. The offline tau identification efficiency is measured withmore »a precision of 2.5% for hadronically decaying tau leptons with one associated track, and of 4% for the case of three associated tracks, inclusive in pseudorapidity and for a visible transverse energy greater than 20 GeV. For hadronic tau lepton decays selected by offline algorithms, the tau trigger identification efficiency is measured with a precision of 2–8%, depending on the transverse energy. The performance of the tau algorithms, both offline and at the trigger level, is found to be stable with respect to the number of concurrent proton–proton interactions and has supported a variety of physics results using hadronically decaying tau leptons at ATLAS.« less

  2. Measurement of the top quark mass in the tt¯? lepton+jets and tt¯? dilepton channels using ?s = 7   TeV ATLAS data

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

    Aad, G.

    2015-07-17

    The top quark mass was measured in the channels tt¯? lepton+jets and tt¯? dilepton (lepton = e,?) based on ATLAS data recorded in 2011. The data were taken at the LHC with a proton–proton centre-of-mass energy of ?s = 7 TeV and correspond to an integrated luminosity of 4.6 fb–1. The tt¯? lepton+jets analysis uses a three-dimensional template technique which determines the top quark mass together with a global jet energy scale factor (JSF), and a relative b-to-light-jet energy scale factor (bJSF), where the terms b-jets and light-jets refer to jets originating from b-quarks and u, d, c, s-quarks ormore »gluons, respectively. The analysis of the tt¯? dilepton channel exploits a one-dimensional template method using the m?b observable, defined as the average invariant mass of the two lepton+b-jet pairs in each event. The top quark mass is measured to be 172.33 ± 0.75 (stat + JSF + bJSF) ± 1.02(syst) GeV, and 173.79 ± 0.54(stat) ± 1.30(syst) GeV in the tt¯? lepton+jets and tt¯? dilepton channels, respectively. Thus, the combination of the two results yields mtop = 172.99 ± 0.48(stat) ± 0.78(syst) GeV, with a total uncertainty of 0.91 GeV.« less

  3. Vortex pinning by inhomogeneities in type-II superconductors

    E-Print Network [OSTI]

    Chapman, Jon

    Vortex pinning by inhomogeneities in type-II superconductors S.J. Chapman #3;y G. Richardson zx of a curvilinear vortex in an inhomogeneous type-II superconducting material in the limit as the vortex core radius of the superconducting electrons acts as a pinning potential for the vortex, so that vortices will be attracted

  4. Imaging Electrons in Few-Electron Quantum Dots

    E-Print Network [OSTI]

    Imaging Electrons in Few-Electron Quantum Dots A thesis presented by Parisa Fallahi to The Division Electrons in Few-Electron Quantum Dots Abstract Electrons in a one-electron quantum dot were imaged the tip-induced shift of the electron energy state in the dot. A technique for extracting the amplitude

  5. Composite mixed oxide ionic and electronic conductors for hydrogen separation

    DOE Patents [OSTI]

    Gopalan, Srikanth (Westborough, MA); Pal, Uday B. (Dover, MA); Karthikeyan, Annamalai (Quincy, MA); Hengdong, Cui (Allston, MA)

    2009-09-15

    A mixed ionic and electronic conducting membrane includes a two-phase solid state ceramic composite, wherein the first phase comprises an oxygen ion conductor and the second phase comprises an n-type electronically conductive oxide, wherein the electronically conductive oxide is stable at an oxygen partial pressure as low as 10.sup.-20 atm and has an electronic conductivity of at least 1 S/cm. A hydrogen separation system and related methods using the mixed ionic and electronic conducting membrane are described.

  6. Catalac free electron laser

    DOE Patents [OSTI]

    Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

    1982-01-01

    A catalac free electron laser using a rf linac (catalac) which acts as a catalyst to accelerate an electron beam in an initial pass through the catalac and decelerate the electron beam during a second pass through the catalac. During the second pass through the catalac, energy is extracted from the electron beam and transformed to energy of the accelerating fields of the catalac to increase efficiency of the device. Various embodiments disclose the use of post linacs to add electron beam energy extracted by the wiggler and the use of supplementary catalacs to extract energy at various energy peaks produced by the free electron laser wiggler to further enhance efficiency of the catalac free electron laser. The catalac free electron laser can be used in conjunction with a simple resonator, a ring resonator or as an amplifier in conjunction with a master oscillator laser.

  7. TYPES OF NONIMMIGRANT VISAS Type Description

    E-Print Network [OSTI]

    for pleasure and cannot receive any type of payments. C-1*, Aliens in travel status while travelling directly through the C-2*, United States. C-3* D-1 Alien crewman on shore leave or transferring to another vessel is grounds for deportation. E-1 Aliens who conduct trade or inventories between the United States

  8. Neutrinos in the Electron

    E-Print Network [OSTI]

    E. L. Koschmieder

    2006-09-26

    We will show that one half of the rest mass of the electron is equal to the sum of the rest masses of electron neutrinos and that the other half of the rest mass of the electron is given by the energy in the sum of electric oscillations. With this composition we can explain the rest mass, the electric charge, the spin and the magnetic moment of the electron.

  9. electronic reprint Acta Crystallographica Section B

    E-Print Network [OSTI]

    Vocadlo, Lidunka

    electronic reprint Acta Crystallographica Section B Structural Science ISSN 0108-7681 Structures, concluding that a CsCl-type structure would be the thermo- dynamically most stable phase for pressures calculations Lidunka Vocadlo, Geoffrey D. Price and I. G. Wood Copyright © International Union

  10. Averages of B-Hadron, C-Hadron, and tau-lepton properties as of early 2012

    SciTech Connect (OSTI)

    Amhis, Y.; et al.

    2012-07-01

    This article reports world averages of measurements of b-hadron, c-hadron, and tau-lepton properties obtained by the Heavy Flavor Averaging Group (HFAG) using results available through the end of 2011. In some cases results available in the early part of 2012 are included. For the averaging, common input parameters used in the various analyses are adjusted (rescaled) to common values, and known correlations are taken into account. The averages include branching fractions, lifetimes, neutral meson mixing parameters, CP violation parameters, parameters of semileptonic decays and CKM matrix elements.

  11. Notice Type: Presolicitation

    E-Print Network [OSTI]

    : 334 -- Computer and Electronic Product Manufacturing/334515 -- Instrument Manufacturing for Measuring-SMU and 1 each Ultra-Fast I-V Module P/N: 4225-PMU. (Microsoft IE required). Additional specifications

  12. Notice Type: Presolicitation

    E-Print Network [OSTI]

    -- Computer and Electronic Product Manufacturing/334515 -- Instrument Manufacturing for Measuring and Testing Polarization P/N: WS-AA-2000S-ZZ-H. (Microsoft IE required). Additional specifications and opening and closing

  13. Dark Energy and Electrons

    E-Print Network [OSTI]

    Burra G. Sidharth

    2008-08-05

    In the light of recent developments in Dark Energy, we consider the electron in a such a background field and show that at the Compton wavelength the electron is stable, in that the Cassini inward pressure exactly counterbalances the outward Coulomb repulsive pressure thus answering a problem of the earlier electron theory.

  14. Electronic Monitoring White Papers

    E-Print Network [OSTI]

    Electronic Monitoring White Papers February 15, 2013 Source: NOAA Fisheries Office of Policy & Electronic Monitoring Working Group U.S. Department of Commerce National Oceanic & Atmospheric Administration.holliday@noaa.gov #12;B-1 Appendix B - Electronic Monitoring White Paper Existing Technologies National Oceanic

  15. Electronics, Electrical Engineering

    E-Print Network [OSTI]

    SCHOOL OF Electronics, Electrical Engineering and Computer Science IS IN YOUR HANDS THE FUTURE #12;SCHOOL OF Electronics, Electrical Engineering and Computer Science2 CAREERS IN ELECTRONICS, ELECTRICAL ENGINEERING AND COMPUTER SCIENCE This is an exciting time to join the School of EEECS at Queen's University

  16. Search for baryon-number and lepton-number violating decays of $Lambda$ hyperons using the CLAS detector at Jefferson Laboratory

    SciTech Connect (OSTI)

    McCracken, Michael E.

    2015-10-09

    We present a search for ten baryon-number violating decay modes of $\\Lambda$ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state ($\\Lambda \\rightarrow m \\ell$) and conserve either the sum or the difference of baryon and lepton number ($B \\pm L$). The tenth decay mode ($\\Lambda \\rightarrow \\bar{p}\\pi^+$) represents a difference in baryon number of two units and no difference in lepton number. We observe no significant signal and set upper limits on the branching fractions of these reactions in the range $(4-200)\\times 10^{-7}$ at the $90\\%$ confidence level.

  17. Search for baryon-number and lepton-number violating decays of $Lambda$ hyperons using the CLAS detector at Jefferson Laboratory

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

    McCracken, Michael E.

    2015-10-09

    We present a search for ten baryon-number violating decay modes of $\\Lambda$ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state ($\\Lambda \\rightarrow m \\ell$) and conserve either the sum or the difference of baryon and lepton number ($B \\pm L$). The tenth decay mode ($\\Lambda \\rightarrow \\bar{p}\\pi^+$) represents a difference in baryon number of two units and no difference in lepton number. We observe no significant signal and set upper limits on the branching fractions of these reactions in the range $(4-200)\\times 10^{-7}$more »at the $90\\%$ confidence level.« less

  18. Search for anomalous production of prompt like-sign lepton pairs at $ \\sqrt{s}=7\\;\\mathrm{TeV} $ with the ATLAS detector

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

    Aad, G.

    2012-12-03

    An inclusive search for anomalous production of two prompt, isolated leptons with the same electric charge is presented. The search is performed in a data sample corresponding to 4.7 fb-1 of integrated luminosity collected in 2011 at ?s = 7 TeV with the ATLAS detector at the LHC. Pairs of leptons (e± e±, e± ?±, and ?± ?±) with large transverse momentum are selected, and the dilepton invariant mass distribution is examined for any deviation from the Standard Model expectation. No excess is found, and upper limits on the production cross section of like-sign lepton pairs from physics processes beyondmore »the Standard Model are placed as a function of the dilepton invariant mass within a fiducial region close to the experimental selection criteria. The 95% confidence level upper limits on the cross section of anomalous e± e±, e± ?±, or ?± ?± production range between 1.7 fb and 64 fb depending on the dilepton mass and flavour combination.« less

  19. Electron Beam for LHC

    E-Print Network [OSTI]

    Mieczyslaw Witold Krasny

    2004-05-13

    A method of delivering a monochromatic electron beam to the LHC interaction points is proposed. In this method, heavy ions are used as carriers of the projectile electrons. Acceleration, storage and collision-stability aspects of such a hybrid beam is discussed and a new beam-cooling method is presented. This discussion is followed by a proposal of the Parasitic Ion-Electron collider at LHC (PIE@LHC). The PIE@LHC provides an opportunity, for the present LHC detectors, to enlarge the scope of their research program by including the program of electron-proton and electron-nucleuscollisions with minor machine and detector investments.

  20. SOLUTION-PROCESSED INORGANIC ELECTRONICS

    E-Print Network [OSTI]

    Bakhishev, Teymur

    2011-01-01

    Conductors for Flexible Electronics,” Journal of Thefor low-cost and flexible electronics. Parts of his workwidespread use in flexible electronics. From an economic

  1. SOLUTION-PROCESSED INORGANIC ELECTRONICS

    E-Print Network [OSTI]

    Bakhishev, Teymur

    2011-01-01

    Solution-Processed Graphene Electronics,” Nano Letters, vol.applications,” Organic Electronics, vol. 12, no. 2, pp. 249-design in organic electronics by dual-gate technology,” in

  2. Self-sustained asymmetry of lepton-number emission: a new phenomenon during the supernova shock-accretion phase in three dimensions

    SciTech Connect (OSTI)

    Tamborra, Irene; Raffelt, Georg G. [Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Föhringer Ring 6, D-80805 München (Germany); Hanke, Florian; Janka, Hans-Thomas; Müller, Bernhard [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany); Marek, Andreas [Rechenzentrum der Max-Planck-Gesellschaft, Boltzmannstr. 2, D-85741 Garching (Germany)

    2014-09-10

    During the stalled-shock phase of our three-dimensional, hydrodynamical core-collapse simulations with energy-dependent, three-flavor neutrino transport, the lepton-number flux (? {sub e} minus ?-bar {sub e}) emerges predominantly in one hemisphere. This novel, spherical-symmetry breaking neutrino-hydrodynamical instability is termed LESA for 'Lepton-number Emission Self-sustained Asymmetry'. While the individual ? {sub e} and ?-bar {sub e} fluxes show a pronounced dipole pattern, the heavy-flavor neutrino fluxes and the overall luminosity are almost spherically symmetric. Initially, LESA seems to develop stochastically from convective fluctuations. It exists for hundreds of milliseconds or more and persists during violent shock sloshing associated with the standing accretion shock instability. The ? {sub e} minus ?-bar {sub e} flux asymmetry originates predominantly below the neutrinosphere in a region of pronounced proto-neutron star (PNS) convection, which is stronger in the hemisphere of enhanced lepton-number flux. On this side of the PNS, the mass accretion rate of lepton-rich matter is larger, amplifying the lepton-emission asymmetry, because the spherical stellar infall deflects on a dipolar deformation of the stalled shock. The increased shock radius in the hemisphere of less mass accretion and minimal lepton-number flux ( ?-bar {sub e} flux maximum) is sustained by stronger convection on this side, which is boosted by stronger neutrino heating due to ??{sub ?-bar{sub e}}?>??{sub ?{sub e}}?. Asymmetric heating thus supports the global deformation despite extremely nonstationary convective overturn behind the shock. While these different elements of the LESA phenomenon form a consistent picture, a full understanding remains elusive at present. There may be important implications for neutrino-flavor oscillations, the neutron-to-proton ratio in the neutrino-heated supernova ejecta, and neutron-star kicks, which remain to be explored.

  3. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    SciTech Connect (OSTI)

    Grillo, Vincenzo; Mafakheri, Erfan; Frabboni, Stefano

    2014-01-27

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science.

  4. Kinetic and electron-electron energies for convex sums of ground state densities with degeneracies and fractional electron number

    SciTech Connect (OSTI)

    Levy, Mel, E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States) [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States); Department of Physics, North Carolina A and T State University, Greensboro, North Carolina 27411 (United States); Department of Chemistry, Tulane University, New Orleans, Louisiana 70118 (United States); Anderson, James S. M.; Zadeh, Farnaz Heidar; Ayers, Paul W., E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario (Canada)

    2014-05-14

    Properties of exact density functionals provide useful constraints for the development of new approximate functionals. This paper focuses on convex sums of ground-level densities. It is observed that the electronic kinetic energy of a convex sum of degenerate ground-level densities is equal to the convex sum of the kinetic energies of the individual degenerate densities. (The same type of relationship holds also for the electron-electron repulsion energy.) This extends a known property of the Levy-Valone Ensemble Constrained-Search and the Lieb Legendre-Transform refomulations of the Hohenberg-Kohn functional to the individual components of the functional. Moreover, we observe that the kinetic and electron-repulsion results also apply to densities with fractional electron number (even if there are no degeneracies), and we close with an analogous point-wise property involving the external potential. Examples where different degenerate states have different kinetic energy and electron-nuclear attraction energy are given; consequently, individual components of the ground state electronic energy can change abruptly when the molecular geometry changes. These discontinuities are predicted to be ubiquitous at conical intersections, complicating the development of universally applicable density-functional approximations.

  5. arXiv:0708.1344v1[hep-ph]9Aug2007 NUHEP-TH/07-10 A Survey of Lepton Number Violation Via Effective Operators

    E-Print Network [OSTI]

    number violating phenomena. These include searches for neutrinoless double-beta decay and rare meson 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

  6. 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]

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

    2014-11-06

    with missing transverse momentum and at least three b-jets using 20.1 fb?1 of pp collisions at ?s = 8 TeV with the ATLAS detector,ATLAS-CONF-2013-061, CERN, Geneva Switzerland (2013) [INSPIRE]. [2] ATLAS collaboration, Background studies for top-pair production... in lepton plus jets final states in ?s = 7 TeV ATLAS data, ATLAS-CONF-2010-087, CERN, Geneva Switzerland (2010) [INSPIRE]. [3] ATLAS collaboration, Search for supersymmetry using final states with one lepton, jets and missing transverse momentum...

  7. Electron thermal conductivity owing to collisions between degenerate electrons

    E-Print Network [OSTI]

    P. S. Shternin; D. G. Yakovlev

    2006-08-17

    We calculate the thermal conductivity of electrons produced by electron-electron Coulomb scattering in a strongly degenerate electron gas taking into account the Landau damping of transverse plasmons. The Landau damping strongly reduces this conductivity in the domain of ultrarelativistic electrons at temperatures below the electron plasma temperature. In the inner crust of a neutron star at temperatures T electron conductivity due to electron-ion (electron-phonon) scattering and becomes competitive with the the electron conductivity due to scattering of electrons by impurity ions.

  8. Typed Self-Optimization

    E-Print Network [OSTI]

    Brown, Matt

    2013-01-01

    type T y[O]. The operator IsIs is self-applicative, in thatargument t is any of Is[O] or IsIs, and otherwise behavesproof constant introduced by IsIs proves that the type of t

  9. The Working Group M5 on Lepton-Hadron Colliders Conveners: Ilan Ben-Zvi and Georg H. Hoffstaetter

    E-Print Network [OSTI]

    Hoffstaetter, Georg

    ........................................................................... 28 3. eRHIC, Electron-Hadron Collisions with RHIC

  10. Electron emitting filaments for electron discharge devices

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Pincosy, Philip A. (Oakland, CA); Ehlers, Kenneth W. (Alamo, CA)

    1988-01-01

    Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600.degree. C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for non-uniform current distribution along the filament due to the emission of electrons from the filament.

  11. Electron emitting filaments for electron discharge devices

    DOE Patents [OSTI]

    Leung, K.N.; Pincosy, P.A.; Ehlers, K.W.

    1983-06-10

    Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600/sup 0/C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for nonuniform current distribution along the filament due to the emission of electrons from the filament.

  12. Metamaterials for Ballistic Electrons

    E-Print Network [OSTI]

    Daniela Dragoman; Mircea Dragoman

    2007-01-02

    The paper presents a metamaterial for ballistic electrons, which consists of a quantum barrier formed in a semiconductor with negative effective electron mass. This barrier is the analogue of a metamaterial for electromagnetic waves in media with negative electrical permittivity and magnetic permeability. Besides applications similar to those of optical metamaterials, a nanosized slab of a metamaterial for ballistic electrons, sandwiched between quantum wells of positive effective mass materials, reveals unexpected conduction properties, e.g. single or multiple room temperature negative differential conductance regions at very low voltages and with considerable peak-to-valley ratios, while the traversal time of ballistic electrons can be tuned to larger or smaller values than in the absence of the metamaterial slab. Thus, slow and fast electrons, analogous to slow and fast light, occur in metamaterials for ballistic electrons.

  13. Ceramic Electron Multiplier

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

    Comby, G.

    1996-10-01

    The Ceramic Electron Multipliers (CEM) is a compact, robust, linear and fast multi-channel electron multiplier. The Multi Layer Ceramic Technique (MLCT) allows to build metallic dynodes inside a compact ceramic block. The activation of the metallic dynodes enhances their secondary electron emission (SEE). The CEM can be used in multi-channel photomultipliers, multi-channel light intensifiers, ion detection, spectroscopy, analysis of time of flight events, particle detection or Cherenkov imaging detectors. (auth)

  14. Field emission electron source

    DOE Patents [OSTI]

    Zettl, Alexander Karlwalter (Kensington, CA); Cohen, Marvin Lou (Berkeley, CA)

    2000-01-01

    A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA/cm.sup.2 at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

  15. Controlling Graphene's Electronic Structure

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

    semiconductor devices at low temperatures and high magnetic fields). Among its novel properties, graphene's electrical charge carriers (electrons and holes) move through a solid...

  16. Hybrid type checking

    E-Print Network [OSTI]

    Flanagan, C

    2006-01-01

    O’Callahan and J. -D. Choi. Hybrid dynamic data race detec-subtyping is sound, the hybrid compilation algorithmHybrid Type Checking Cormac Flanagan Department of Computer

  17. Fejer-type inequalities

    E-Print Network [OSTI]

    Mitroi, F C

    2011-01-01

    The aim of this paper is to present some new Fejer-type results for convex functions. Improvements of Young's inequality (the arithmetic-geometric mean inequality) and other applications to special means are pointed as well.

  18. Notice Type: Presolicitation

    E-Print Network [OSTI]

    components NAICS Code: 334 -- Computer and Electronic Product Manufacturing/334413 -- Semiconductor and Related Device Manufacturing Synopsis: Added: Sep 05, 2014 8:20 am The Naval Research Laboratory has System P/N: ATC-2200-HY. (Microsoft IE required). Additional specifications and opening and closing dates

  19. Notice Type: Presolicitation

    E-Print Network [OSTI]

    : 334 -- Computer and Electronic Product Manufacturing/334516 -- Analytical Laboratory Instrument Manufacturing Synopsis: Added: Sep 05, 2014 1:20 pm The Naval Research Laboratory has a requirement for 1 each. (Microsoft IE required). Additional specifications and opening and closing dates will appear in the RFQ

  20. Notice Type: Presolicitation

    E-Print Network [OSTI]

    components NAICS Code: 334 -- Computer and Electronic Product Manufacturing/334413 -- Semiconductor and Related Device Manufacturing Synopsis: Added: Sep 03, 2014 9:36 am The Naval Research Laboratory has-39-FC/APC-V-1. (Microsoft IE required). Additional specifications and opening and closing dates

  1. Notice Type: Presolicitation

    E-Print Network [OSTI]

    : 334 -- Computer and Electronic Product Manufacturing/334516 -- Analytical Laboratory Instrument Manufacturing Synopsis: Added: Sep 03, 2014 2:31 pm The Naval Research Laboratory has a requirement for 1 each/N: 999800.528. (Microsoft IE required). Additional specifications and opening and closing dates will appear

  2. Notice Type: Presolicitation

    E-Print Network [OSTI]

    : 334 -- Computer and Electronic Product Manufacturing/334516 -- Analytical Laboratory Instrument Manufacturing Synopsis: Added: Sep 05, 2014 8:59 am The Naval Research Laboratory has a requirement for 1 each P IE required). Additional specifications and opening and closing dates will appear in the RFQ

  3. Notice Type: Presolicitation

    E-Print Network [OSTI]

    radiation equipment NAICS Code: 334 -- Computer and Electronic Product Manufacturing/334220 -- Radio and Television Broadcasting and Wireless Communications Equipment Manufacturing Synopsis: Added: Jul 25, 2014 6 1x4) Multicouple 30 MHz to 6 GHz M/N: 8MDP-206000E. (Microsoft IE required). Additional

  4. Notice Type: Presolicitation

    E-Print Network [OSTI]

    components NAICS Code: 334 -- Computer and Electronic Product Manufacturing/334413 -- Semiconductor and Related Device Manufacturing Synopsis: Added: Sep 05, 2014 8:45 am The Naval Research Laboratory has a requirement for 1 each P/N: NUU102E UV Laser Engineering Module. (Microsoft IE required). Additional

  5. Measurement of Spin Correlations in $t\\bar{t}$ Events from $pp$ Collisions at $\\sqrt{s}$ = 7 TeV in the Lepton + Jets Final State with the ATLAS Detector

    E-Print Network [OSTI]

    Boris Lemmer

    2014-10-05

    The top quark decays before it hadronises. Before its spin state can be changed in a process of strong interaction, it is directly transferred to the top quark decay products. The top quark spin can be deduced by studying angular distributions of the decay products. The Standard Model predicts the top/anti-top quark ($t\\bar{t}$) pairs to have correlated spins. The degree is sensitive to the spin and the production mechanisms of the top quark. Measuring the spin correlation allows to test the predictions. New physics effects can be reflected in deviations from the prediction. In this thesis the spin correlation of $t\\bar{t}$ pairs, produced at a centre-of-mass energy of $\\sqrt{s} = 7\\,$TeV and reconstructed with the ATLAS detector, is measured. The dataset corresponds to an integrated luminosity of $4.6~\\text{fb}^{-1}$. $t\\bar{t}$ pairs are reconstructed in the $\\ell$+jets channel using a kinematic likelihood fit offering the identification of light up- and down-type quarks from the $t \\rightarrow bW \\rightarrow bq\\bar{q}'$ decay. The spin correlation is measured via the distribution of the azimuthal angle $\\Delta\\phi$ between two top quark spin analyzers in the laboratory frame. It is expressed as the degree of $t\\bar{t}$ spin correlation predicted by the Standard Model, $f_{\\text{SM}}$. The results of \\begin{align*} &f_{\\text{SM}}( \\Delta\\phi(\\text{charged lepton, down-type quark} )) &= 1.53 \\pm 0.14\\,\\text{(stat.)} \\pm 0.32\\,\\text{(syst.)}, \\\\ &f_{\\text{SM}} ( \\Delta\\phi(\\text{charged lepton, b-quark} )) &= 0.53 \\pm 0.18\\,\\text{(stat.)} \\pm 0.49\\,\\text{(syst.)}, \\\\ &f_{\\text{SM}} ( \\Delta\\phi(\\text{combined})) &= 1.12 \\pm 0.11\\,\\text{(stat.)} \\pm 0.22\\,\\text{(syst.)}, \\end{align*} are consistent with the Standard Model prediction of $f_{\\text{SM}}= 1.0$.

  6. Application of nuclear density functionals to lepton number violating weak processes

    SciTech Connect (OSTI)

    Rodriguez, Tomas R.; Martinez-Pinedo, Gabriel

    2012-10-20

    We present an application of energy density functional methods with the Gogny interaction to the calculation of nuclear matrix elements (NME) for neutrinoless double beta decay and double electron capture. Beyond mean field effects have been included by particle number and angular momentum restoration and shape mixing within the generator coordinate method (GCM) framework. We analyze in detail the NME for {sup 116}Cd nucleus which is one of the most promising candidates to detect neutrinoless double beta decay.

  7. Search for Flavor-Changing Neutral Current and Lepton-Flavor Violating Decays of D[superscript 0]-->l+l-

    E-Print Network [OSTI]

    Cowan, Ray Franklin

    We report on a search for the flavor-changing neutral current decays D0?e+e- and D0??+?-, and the lepton-flavor violating decay D0?e±??. The measurement is based on 122??fb-1 of data collected by the BABAR detector at the ...

  8. NLO QCD corrections to off-shell top-antitop production with leptonic decays in association with a Higgs boson at the LHC

    E-Print Network [OSTI]

    Denner, Ansgar

    2015-01-01

    We compute the hadronic production of top-antitop pairs in association with a Higgs boson at next-to-leading-order QCD, including the decay of the top and antitop quark into bottom quarks and leptons. Our computation is based on full leading and next-to-leading-order matrix elements for $e^+ \

  9. Search for standard model production of four top quarks in the lepton + jets channel in pp collisions at ?s = 8 TeV

    E-Print Network [OSTI]

    CMS Collaboration

    A search is presented for standard model (SM) production of four top quarks (tt¯tt¯) in pp collisions in the lepton + jets channel. The data correspond to an integrated luminosity of 19.6 fb[superscript ?1] recorded at a ...

  10. Search for new phenomena in events with three charged leptons at sqrt[s]=7??TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A generic search for anomalous production of events with at least three charged leptons is presented. The search uses a pp-collision data sample at a center-of-mass energy of ?s=7??TeV corresponding to 4.6??fb-1 of integrated ...

  11. Search for physics beyond the standard model in final states with a lepton and missing transverse energy in proton-proton collisions at $\\sqrt{s}$ = 8 TeV

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

    Khachatryan, Vardan

    2015-05-22

    A search for new physics in proton-proton collisions having final states with an electron or muon and missing transverse energy is presented. The analysis uses data collected in 2012 with the CMS detector, at an LHC center-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of 19.7 fb$^{-1}$. No significant deviation of the transverse mass distribution of the charged lepton-neutrino system from the standard model prediction is found. Mass exclusion limits of up to 3.28 TeV at a 95% confidence level for a W$^{\\prime}$ boson with the same couplings as that of the standard model W boson aremore »determined. Results are also derived in the framework of split universal extra dimensions, and exclusion limits on Kaluza-Klein W$^{(2)}_{{\\rm KK}}$ states are found. The final state with large missing transverse energy also enables a search for dark matter production with a recoiling W boson, with limits set on the mass and the production cross section of potential candidates. Finally, limits are established for a model including interference between a left-handed W$^{\\prime}$ boson and the standard model W boson, and for a compositeness model.« less

  12. Search for physics beyond the standard model in final states with a lepton and missing transverse energy in proton-proton collisions at $\\sqrt{s}$ = 8 TeV

    SciTech Connect (OSTI)

    Khachatryan, Vardan

    2015-05-22

    A search for new physics in proton-proton collisions having final states with an electron or muon and missing transverse energy is presented. The analysis uses data collected in 2012 with the CMS detector, at an LHC center-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of 19.7 fb$^{-1}$. No significant deviation of the transverse mass distribution of the charged lepton-neutrino system from the standard model prediction is found. Mass exclusion limits of up to 3.28 TeV at a 95% confidence level for a W$^{\\prime}$ boson with the same couplings as that of the standard model W boson are determined. Results are also derived in the framework of split universal extra dimensions, and exclusion limits on Kaluza-Klein W$^{(2)}_{{\\rm KK}}$ states are found. The final state with large missing transverse energy also enables a search for dark matter production with a recoiling W boson, with limits set on the mass and the production cross section of potential candidates. Finally, limits are established for a model including interference between a left-handed W$^{\\prime}$ boson and the standard model W boson, and for a compositeness model.

  13. Simulations of Gaussian electron guns for RHIC electron lens

    SciTech Connect (OSTI)

    Pikin, A.

    2014-02-28

    Simulations of two versions of the electron gun for RHIC electron lens are presented. The electron guns have to generate an electron beam with Gaussian radial profile of the electron beam density. To achieve the Gaussian electron emission profile on the cathode we used a combination of the gun electrodes and shaping of the cathode surface. Dependence of electron gun performance parameters on the geometry of electrodes and the margins for electrodes positioning are presented.

  14. Linkping University Electronic Press

    E-Print Network [OSTI]

    Zhao, Yuxiao

    Linköping University Electronic Press Strategic Plan 2009-2011 December, 2008 1 #12;1. Background As of January 1st , 2008, Linköping University Electronic Press (LiU E-Press) became a unit withinU E-Press. For these reasons, the Strategic Plan for LiU E-Press (2007- 2009) is being updated

  15. Electronic Mail Analysis Capability

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-01-08

    Establishes the pilot program to test the Department of Energy (DOE) Electronic Mail Analysis Capability (EMAC), which will be used to monitor and analyze outgoing and incoming electronic mail (e-mail) from the National Nuclear Security Administration (NNSA) and DOE laboratories that are engaged in nuclear weapons design or work involving special nuclear material. No cancellation.

  16. ASSISTED ELECTRONIC COMMUNICATION IN

    E-Print Network [OSTI]

    ;Department of Health Project 121-7184 Final Report 3 Executive Summary In the Assisted Electronic Project 121-7184 Final Report - 05.04.04 Kettering General NHS Hospital Trust University of Hertfordshire of Health Project 121-7184 Final Report 2 KEY to Common Abbreviations used: AEC(P) ­ Assisted Electronic

  17. Electron: Cluster interactions

    SciTech Connect (OSTI)

    Scheidemann, A.A.; Kresin, V.V.; Knight, W.D.

    1994-02-01

    Beam depletion spectroscopy has been used to measure absolute total inelastic electron-sodium cluster collision cross sections in the energy range from E {approximately} 0.1 to E {approximately} 6 eV. The investigation focused on the closed shell clusters Na{sub 8}, Na{sub 20}, Na{sub 40}. The measured cross sections show an increase for the lowest collision energies where electron attachment is the primary scattering channel. The electron attachment cross section can be understood in terms of Langevin scattering, connecting this measurement with the polarizability of the cluster. For energies above the dissociation energy the measured electron-cluster cross section is energy independent, thus defining an electron-cluster interaction range. This interaction range increases with the cluster size.

  18. Electrons and Mirror Symmetry

    SciTech Connect (OSTI)

    Kumar, Krishna (University of Massachusetts, Amherst) [University of Massachusetts, Amherst

    2007-04-04

    The neutral weak force between an electron and a target particle, mediated by the Z boson, can be isolated by measuring the fractional change under a mirror reflection of the scattering probability of relativistic longitudinally polarized electrons off unpolarized targets. This technique yields neutral weak force measurements at a length scale of 1 femtometer, in contrast to high energy collider measurements that probe much smaller length scales. Study of the variation of the weak force over a range of length scales provides a stringent test of theory, complementing collider measurements. We describe a recent measurement of the neutral weak force between two electrons by the E158 experiment at the Stanford Linear Accelerator Center. While the weak force between an electron and positron has been extensively studied, that between two electrons had never directly been measured. We conclude by discussing prospects for even more precise measurements at future facilities.

  19. Electrons and Mirror Symmetry

    ScienceCinema (OSTI)

    Kumar, Krishna

    2009-09-01

    The neutral weak force between an electron and a target particle, mediated by the Z boson, can be isolated by measuring the fractional change under a mirror reflection of the scattering probability of relativistic longitudinally polarized electrons off unpolarized targets. This technique yields neutral weak force measurements at a length scale of 1 femtometer, in contrast to high energy collider measurements that probe much smaller length scales. Study of the variation of the weak force over a range of length scales provides a stringent test of theory, complementing collider measurements. We describe a recent measurement of the neutral weak force between two electrons by the E158 experiment at the Stanford Linear Accelerator Center. While the weak force between an electron and positron has been extensively studied, that between two electrons had never directly been measured. We conclude by discussing prospects for even more precise measurements at future facilities.

  20. Herwig++ Monte Carlo At Next-To-Leading Order for e+e- annihilation and lepton pair production.

    E-Print Network [OSTI]

    Latunde-Dada, Oluseyi

    . They are the emission of a gluon, q + q¯ ? V + g and the QCD Compton subprocess, q + g ? V + q. Both are illustrated in Figure 4. q _p pq pV pg q q V g _ Vq g q pV pqpg pq ’ Figure 4: NLO diagrams for lepton pair production. – 3 – The generic MC@NLO method is described... S 2? CF ( 3 (1? x)+ ? 6? 4x + 2(1 + x2) ( ln(1? x) 1? x ) + + ( 1 + 4 3 ?2 ) ?(1? x) )) ?Mqq¯ } + FV gMqq¯] . (7.3) where J = Jq ?Jq¯. A similar procedure can be adopted for the Compton subprocess which as discussed has one jet region. In this case...

  1. Langmuir wave-packet generation from an electron beam propagating in the inhomogeneous solar wind.

    E-Print Network [OSTI]

    California at Berkeley, University of

    Langmuir wave-packet generation from an electron beam propagating in the inhomogeneous solar wind of an electron beam in an homogeneous plasma leads to the generation of Lang- muir waves, that are electrostatic of the generation of plasma waves during type III radio bursts or close to the electron foreshock. It is also known

  2. Numerical Implementation of lepton-nucleus interactions and its effect on neutrino oscillation analysis

    E-Print Network [OSTI]

    C. -M. Jen; A. Ankowski; O. Benhar; A. P. Furmanski; L. N. Kalousis; C. Mariani

    2014-10-13

    We discuss the implementation of the nuclear model based on realistic nuclear spectral functions in the GENIE neutrino interaction generator. Besides improving on the Fermi gas description of the nuclear ground state, our scheme involves a new prescription for $Q^2$ selection, meant to efficiently enforce energy momentum conservation. The results of our simulations, validated through comparison to electron scattering data, have been obtained for a variety of target nuclei, ranging from carbon to argon, and cover the kinematical region in which quasi elastic scattering is the dominant reaction mechanism. We also analyse the influence of the adopted nuclear model on the determination of neutrino oscillation parameters.

  3. Agreement Type Union

    National Nuclear Security Administration (NNSA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouthReporteeo | National Nucleara min [Type the abstract of theType

  4. Coherent electron cooling

    SciTech Connect (OSTI)

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  5. Aerogels for electronics

    SciTech Connect (OSTI)

    Hrubesh, L.W.

    1994-10-01

    In addition to their other exceptional properties, aerogels also exhibit unusual dielectric and electronic properties due to their nano-sized structures and high porosities. For example, aerogels have the lowest dielectric constants measured for a solid material (having values approaching 1.0); they have exceptionally high dielectric resistivities and strengths (i.e., ability to insulate very high voltages); they exhibit low dielectric loss at microwave frequencies; and some aerogels are electrically conductive and photoconductive. These properties are being exploited to provide the next generation of materials for energy storage, low power consumption, and ultra-fast electronics. We are working toward adapting these unusual materials for microelectronic applications, particularly, making thin aerogel films for dielectric substrates and for energy storage devices such as supercapacitors. Measurements are presented in this paper for the dielectric and electronic properties of aerogels, including the dielectric constant, loss factor, dielectric and electrical conductivity, volume resistivity, and dielectric strength. We also describe methods to form and characterize thin aerogel films which are being developed for numerous electronic applications. Finally, some of the electronic applications proposed for aerogels are presented. Commercialization of aerogels for electronics must await further feasibility, prototype development, and cost studies, but they are one of the key materials and are sure to have a major impact on future electronics.

  6. Nucleosynthesis in Type Ia Supernovae

    E-Print Network [OSTI]

    K. Nomoto; K. Iwamoto; N. Nakasato; F. -K. Thielemann; F. Brachwitz; T. Tsujimoto; Y. Kubo; N. Kishimoto

    1997-06-03

    Among the major uncertainties involved in the Chandrasekhar mass models for Type Ia supernovae are the companion star of the accreting white dwarf (or the accretion rate that determines the carbon ignition density) and the flame speed after ignition. We present nucleosynthesis results from relatively slow deflagration (1.5 - 3 % of the sound speed) to constrain the rate of accretion from the companion star. Because of electron capture, a significant amount of neutron-rich species such as ^{54}Cr, ^{50}Ti, ^{58}Fe, ^{62}Ni, etc. are synthesized in the central region. To avoid the too large ratios of ^{54}Cr/^{56}Fe and ^{50}Ti/^{56}Fe, the central density of the white dwarf at thermonuclear runaway must be as low as \\ltsim 2 \\e9 \\gmc. Such a low central density can be realized by the accretion as fast as $\\dot M \\gtsim 1 \\times 10^{-7} M_\\odot yr^{-1}$. These rapidly accreting white dwarfs might correspond to the super-soft X-ray sources.

  7. The geometry of electron wave functions

    SciTech Connect (OSTI)

    Aminov, Yurii A

    2013-02-28

    To each wave function we assign a codimension-two submanifold in Euclidean space. We study the case of the wave function of a single electron in the hydrogen atom or other hydrogen-type atoms with quantum numbers n, l, m in detail. We prove theorems describing the behaviour of the scalar and sectional curvature of the constructed submanifold, depending on the quantum numbers. We also consider the external geometry of the submanifold. Bibliography: 9 titles.

  8. Basics, types Evolution

    E-Print Network [OSTI]

    Crenshaw, Michael

    to nuclear fusion. · Novae radiate primarily in the UV to X-ray region. · Types: ­ Classical Novae: only one is hot enough for explosive fusion. For classical novae, this happens on a time scale of 103 ­ 105 years. · Thermonuclear runaway (TNR): capture of protons by heavy elements (CNO cycle), happens in seconds #12;5 Novae

  9. Electron Microscope Facility

    ScienceCinema (OSTI)

    None

    2010-01-08

    Brookhaven Lab is home to one of only a few Scanning Transmision Electron Microscope (STEM) machines in the world and one of the few that can image single heavy atoms.

  10. Matter & Energy Electronics

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    See also: Matter & Energy Detectors· Electronics· Technology· Medical Technology· Weapons Technology · Organic Chemistry· Reference Hydrogen chloride· Photography· Catalytic converter· Nanomedicine a series of tiny colored dots ­ each a different pigment ­ on an inert backing such as paper, plastic

  11. Toward pure electronic spectroscopy

    E-Print Network [OSTI]

    Petrovi?, Vladimir, 1978-

    2009-01-01

    In this thesis is summarized the progress toward completing our understanding of the Rydberg system of CaF and developing Pure Electronic Spectroscopy. The Rydberg system of CaF possesses a paradigmatic character due to ...

  12. VIA ELECTRONIC SUBMISSION

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

    39 MacDougal Street, Third Floor * New York, New York 10012 * (212) 992-8932 * www.policyintegrity.org March 21, 2011 VIA ELECTRONIC SUBMISSION Office of the General Counsel US...

  13. Energy.gov Page Types

    Broader source: Energy.gov [DOE]

    Learn about the standard page types available in the Energy.gov Drupal content management system. For information about other available page types, or to request a new kind of page type, contact...

  14. Practical pluggable types for Java

    E-Print Network [OSTI]

    Papi, Matthew M

    2008-01-01

    This paper introduces the Checker Framework, which supports adding pluggable type systems to the Java language in a backward-compatible way. A type system designer defines type qualifiers and their semantics, and a compiler ...

  15. Window Types | Department of Energy

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

    aluminum or vinyl cladding reduces maintenance requirements. Types of Window Glazing or Glass In addition to choosing a frame type, you will need to consider what type of glazing...

  16. Free electron laser

    DOE Patents [OSTI]

    Villa, Francesco (Alameda, CA)

    1990-01-01

    A high gain, single-pass free electron laser formed of a high brilliance electron injector source, a linear accelerator which imparts high energy to the electron beam, and an undulator capable of extremely high magnetic fields, yet with a very short period. The electron injector source is the first stage (gap) of the linear accelerator or a radial line transformer driven by fast circular switch. The linear accelerator is formed of a plurality of accelerating gaps arranged in series. These gaps are energized in sequence by releasing a single pulse of energy which propagates simultaneously along a plurality of transmission lines, each of which feeds the gaps. The transmission lines are graduated in length so that pulse power is present at each gap as the accelerated electrons pass therethrough. The transmission lines for each gap are open circuited at their ends. The undualtor has a structure similar to the accelerator, except that the transmission lines for each gap are substantially short circuited at their ends, thus converting the electric field into magnetic field. A small amount of resistance is retained in order to generate a small electric field for replenishing the electron bunch with the energy lost as it traverses through the undulator structure.

  17. Events with an Isolated Lepton and Missing Transverse Momentum and Measurement of W Production at HERA

    E-Print Network [OSTI]

    The H1; ZEUS Collaborations

    2010-07-30

    A search for events containing an isolated electron or muon and missing transverse momentum produced in ep collisions is performed with the H1 and ZEUS detectors at HERA. The data were taken in the period 1994-2007 and correspond to an integrated luminosity of 0.98 fb^-1. The observed event yields are in good overall agreement with the Standard Model prediction, which is dominated by single W production. In the e+p data, at large hadronic transverse momentum PtX >25 GeV, a total of 23 events are observed compared to a prediction of 14.0 \\pm 1.9. The total single W boson production cross section is measured as 1.06 \\pm 0.16 (stat.) \\pm 0.07 (sys) pb, in agreement with an SM expectation of 1.26 \\pm 0.19 pb.

  18. Cooling system for electronic components

    DOE Patents [OSTI]

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2015-12-15

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  19. SU-8 doped and encapsulated n-type graphene nanomesh with high air stability

    SciTech Connect (OSTI)

    Al-Mumen, Haider [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States) [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Electrical Engineering, University of Babylon, Babylon (Iraq); Dong, Lixin; Li, Wen, E-mail: wenli@egr.msu.edu [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States)] [Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824 (United States)

    2013-12-02

    N-type doping of graphene with long-term chemical stability in air represents a significant challenge for practical application of graphene electronics. This paper reports a reversible doping method to achieve highly stable n-type graphene nanomeshes, in which the SU-8 photoresist simultaneously serves as an effective electron dopant and an excellent encapsulating layer. The chemically stable n-type characteristics of the SU-8 doped graphene were evaluated in air using their Raman spectra, electrical transport properties, and electronic band structures. The SU-8 doping does minimum damage to the hexagonal carbon lattice of graphene and is completely reversible by removing the uncrosslinked SU-8 resist.

  20. Pseudopotential for the electron-electron interaction

    E-Print Network [OSTI]

    Lloyd-Williams, J. H.; Needs, R. J.; Conduit, G. J.

    2015-08-05

    -of-mass frame with wave vector k ? 0 and angular momentum quantum number `. The Hamiltonian in atomic units is ? 1r2 ddr (r2 d? dr ) + `(`+1) r2 ?+ V (r)? = k2?, and the repulsive Coulomb potential is V (r) = 1/r. The proposed pseudopotential is identical... to fermion anti- symmetry. We solve for the energy of two interacting electrons in the parabolic trap within the center-of-mass frame in which the interacting Hamiltonian for relative mo- tion is Hˆ = ? 1r2 ddr (r2 ddr ) + ?2r2/4 + `(`+ 1)/r2 + V (r), where V...

  1. Dust around Type Ia supernovae

    E-Print Network [OSTI]

    Wang, Lifan

    2005-01-01

    Dust around Type Ia supernovae Lifan Wang 1,2 LawrenceIa. Subject headings: Supernovae: General, Dust, Extinctionline) bands for Type Ia supernovae. (a), upper panel, shows

  2. Sifting Through a Trillion Electrons

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

    Sifting Through a Trillion Electrons Sifting Through a Trillion Electrons Berkeley researchers design strategies for extracting interesting data from massive scientific datasets...

  3. Measuring Speedy Electrons in Silicon

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

    Laser, Supercomputer Measure Speedy Electrons in Silicon Laser, Supercomputer Measure Speedy Electrons in Silicon Simulations at NERSC Help Illuminate Attosecond Laser Experiment...

  4. Electron Trapping by Molecular Vibration

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

    Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally...

  5. Electron Trapping by Molecular Vibration

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

    Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the...

  6. Search for supersymmetry with jets, missing transverse momentum and at least one hadronically decaying ? lepton in proton–proton collisions at ?s = 7 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for production of supersymmetric particles in final states containing jets, missing transverse momentum, and at least one hadronically decaying ? lepton is presented. The data were recorded by the ATLAS experiment ...

  7. Search for Gluinos in Events with Two Same-Sign Leptons, Jets, and Missing Transverse Momentum with the ATLAS Detector in pp Collisions at ?s=7??TeV

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for gluinos decaying via the supersymmetric partner of the top quark using events with two same-sign leptons, jets, and missing transverse momentum. The analysis is performed with 2.05??fb-1 of ...

  8. Search for top squark pair production in final states with one isolated lepton, jets, and missing transverse momentum in ?s = 8 TeV pp collisions with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The results of a search for top squark (stop) pair production in final states with one isolated lepton, jets, and missing transverse momentum are reported. The analysis is performed with proton-proton collision data at ?s ...

  9. Experimental study of the radiation emitted by 180-GeV/c electrons and positrons volume-reflected in a bent crystal

    E-Print Network [OSTI]

    Scandale, Walter; Baricordi, S; Dalpiaz, P; Fiorini, M; Guidi, V; Mazzolari, A; Della Mea, G; Milan, R; Ambrosi, G; Zuccon, P; Bertucci, B; Bürger, W; Duranti, M; Cavoto, G; Santacesaria, R; Valente, P; Luci, C; Iacoangeli, F; Vallazza, E; Afonin, A G; Chesnokov, Yu A; Kotov, V I; Maisheev, V A; Yazynin, I A; Kovalenko, A D; Taratin, A M; Denisov, A S; Gavrikov, Y A; Ivanov, Yu M; Lapina, L P; Malyarenko, L G; Skorogobogatov, V V; Suvorov, V M; Vavilov, S A; Bolognini, D; Hasan, S; Mozzanica, A; Prest, M

    2009-01-01

    The radiation emitted by 180-GeV/c volume-reflected electrons and positrons impinging on a bent crystal has been measured by the H8RD22 Collaboration on the H8 beamline at the CERN SPS. A dedicated spectrometer has been developed to measure high-energy photon spectra (up to ~100 GeV) under volume reflection: photon and charged particle beams have been separated by a bending magnet and leptons were detected and tagged by microstrip silicon detectors and a Pb-scintillator sampling calorimeter. A comparison between the experimental and analytical data for the amorphous and volume-reflection cases is presented and the differences are discussed.

  10. The study of heavy flavors via non-photonic electrons in STAR

    E-Print Network [OSTI]

    Jaroslav Bielcik

    2008-10-30

    The strong suppression of hadrons with high transverse momenta in central Au+Au collisions observed at RHIC is generally interpreted as a consequence of energy loss of energetic partons in the hot and dense matter before fragmenting. The study of heavy quark production tests our understanding of energy loss mechanisms. Heavy quarks were expected to lose less energy in the medium than light quarks and gluons due to the suppression of small-angle gluon radiation. However, the high transverse momentum non-photonic electron spectra, which are dominated by semi-leptonic decays of heavy quarks, show a strong suppression in central Au+Au collisions as well. Current theoretical models do not satisfactory explain this observation. Preliminary non-photonic electron spectra are being extracted for Cu+Cu collisions at $\\sqrt{s_{NN}}$ = 200 GeV. They are compared to the non-photonic electron yields from p+p and Au+Au collisions at the same collision energy. This provides a direct experimental test of the dependence of the non-photonic electron yield on collision system size.

  11. Isolated electrons and muons in events with missing transverse momentum at HERA

    E-Print Network [OSTI]

    Andreev, V; Anthonis, T; Astvatsatourov, A; Babaev, A; Bähr, J; Baranov, P S; Barrelet, E; Bartel, Wulfrin; Baumgartner, S; Becker, J; Beckingham, M; Beglarian, A; Behnke, O; Belousov, A; Berger, C; Berndt, T; Bizot, J C; Böhme, J; Boudry, V; Bracinik, J; Braunschweig, W; Brisson, V; Broker, H B; Brown, D P; Bruncko, Dusan; Büsser, F W; Bunyatyan, A; Burrage, A; Buschhorn, G; Bystritskaya, L; Campbell, A J; Caron, S; Cassol-Brunner, F; Chekelian, V; Clarke, D; Collard, Caroline; Contreras, J G; Coppens, Y R; Coughlan, J A; Cousinou, M C; Cox, B E; Cozzika, G; Cvach, J; Dainton, J B; Dau, W D; Daum, K; Davidsson, M; Delcourt, B; Delerue, N; Demirchyan, R A; de Roeck, A; De Wolf, E A; Diaconu, C A; Dingfelder, J; Dixon, P; Dodonov, V; Dowell, John D; Dubak, A; Duprel, C; Eckerlin, G; Eckstein, D; Efremenko, V; Egli, S; Eichler, R; Eisele, Franz; Ellerbrock, M; Elsen, E; Erdmann, M; Erdmann, W; Faulkner, P J W; Favart, L; Fedotov, A; Felst, R; Ferencei, J; Ferron, S; Fleischer, M; Fleischmann, P; Fleming, Y H; Flucke, G; Flügge, G; Fomenko, A; Foresti, I; Formánek, J; Franke, G; Frising, G; Gabathuler, Erwin; Gabathuler, K; Garvey, J; Gassner, J; Gayler, J; Gerhards, R; Gerlich, C; Ghazaryan, S; Görlich, L; Gogitidze, N; Gorbounov, S; Grab, C; Grabskii, V; Grässler, Herbert; Greenshaw, T; Grindhammer, G; Haidt, Dieter; Hajduk, L; Haller, J; Heinemann, B; Heinzelmann, G; Henderson, R C W; Henschel, H; Henshaw, O; Heremans, R; Herrera-Corral, G; Herynek, I; Hildebrandt, M; Hilgers, M; Hiller, K H; Hladky, J; Hoting, P; Hoffmann, D; Horisberger, R P; Hovhannisyan, A V; Ibbotson, M; Issever, C; Jacquet, M; Jaffré, M; Janauschek, L; Janssen, X; Jemanov, V; Jönsson, L B; Johnson, C; Johnson, D P; Jones, M A S; Jung, H; Kant, D; Kapichine, M; Karlsson, M; Karschnick, O; Katzy, J; Keil, F; Keller, N; Kennedy, J; Kenyon, Ian Richard; Kiesling, C; Kjellberg, P; Klein, M; Kleinwort, C; Kluge, T; Knies, G; Koblitz, B; Kolya, S D; Korbel, V; Kostka, P; Koutouev, R; Koutov, A; Kroseberg, J; Krüger, K; Kueckens, J; Kuhr, T; Landon, M P J; Lange, W; Lastoviicka, T; Laycock, P; Lebedev, A; Leiner, B; Lemrani, R; Lendermann, V; Levonian, S; List, B; Lobodzinska, E; Lobodzinski, B; Loktionova, N A; Lubimov, V; Lüders, S; Lüke, D; Lytkin, L; Malden, N; Malinovskii, E I; Mangano, S; Marage, P; Marks, J; Marshall, R; Martyn, H U; Martyniak, J; Maxfield, S J; Meer, D; Mehta, A; Meier, K; Meyer, A B; Meyer, H; Meyer, J; Michine, S; Mikocki, S; Milstead, D; Mohrdieck, S; Mondragón, M N; Moreau, F; Morozov, A; Morris, J V; Müller, K; Murn, P; Nagovizin, V; Naroska, Beate; Naumann, J; Naumann, T; Newman, P R; Niebergall, F; Niebuhr, C B; Nowak, G; Nozicka, M; Olivier, B; Olsson, J E; Ozerov, D; Panassik, V; Pascaud, C; Patel, G D; Peez, M; Pérez, E; Petrukhin, A; Phillips, J P; Pitzl, D; Pöschl, R; Potachnikova, I; Povh, B; Rauschenberger, J; Reimer, P; Reisert, B; Risler, C; Rizvi, E; Robmann, P; Roosen, R; Rostovtsev, A A; Rusakov, S V; Rybicki, K; Sankey, D P C; Sauvan, E; Schatzel, S; Scheins, J; Schilling, F P; Schleper, P; Schmidt, D; Schmidt, S; Schmitt, S; Schneider, M; Schoeffel, L; Schöning, A; Schörner-Sadenius, T; Schröder, V; Schultz-Coulon, H C; Schwanenberger, C; Sedlak, K; Sefkow, F; Shevyakov, I; Shtarkov, L N; Sirois, Y; Sloan, Terence; Smirnov, P; Soloviev, Yu; South, D; Spaskov, V N; Specka, A E; Spitzer, H; Stamen, R; Stella, B; Stiewe, J; Strauch, I; Straumann, U; Chechelnitskii, S; Thompson, G; Thompson, P D; Tomasz, F; Traynor, D; Truöl, P; Tsipolitis, G; Tsurin, I; Turnau, J; Turney, J E; Tzamariudaki, E; Uraev, A; Urban, M; Usik, A; Valkár, S; Valkárová, A; Vallée, C; Van Mechelen, P; Vargas-Trevino, A; Vasilev, S; Vazdik, Ya A; Veelken, C; Vest, A; Vichnevski, A; Volchinski, V; Wacker, K; Wagner, J; Wallny, R; Waugh, B; Weber, G; Weber, R; Wegener, D; Werner, C; Werner, N; Wessels, M; Wessling, B; Winde, M; Winter, G G; Wissing, C; Woerling, E E; Wünsch, E; Wyatt, A C; Zácek, J; Zaleisak, J; Zhang, Z; Zhokin, A; Zomer, F; Zur Nedden, M

    2003-01-01

    A search for events with a high energy isolated electron or muon and missing transverse momentum has been performed at the electron-proton collider HERA using an integrated luminosity of 13.6 pb-1 in e-p scattering and 104.7 pb-1 in e+p scattering. Within the Standard Model such events are expected to be mainly due to W boson production with subsequent leptonic decay. In e-p interactions one event is observed in the electron channel and none in the muon channel, consistent with the expectation of the Standard Model. In the e+p data a total of 18 events are seen in the electron and muon channels compared to an expectation of 12.4 \\pm 1.7 dominated by W production (9.4 \\pm 1.6). Whilst the overall observed number of events is broadly in agreement with the number predicted by the Standard Model, there is an excess of events with transverse momentum of the hadronic system greater than 25 GeV with 10 events found compared to 2.9 \\pm 0.5 expected. The results are used to determine the cross section for events with ...

  12. Experimental Investigation of Electron-Acoustic Waves in Electron Plasmas

    E-Print Network [OSTI]

    California at San Diego, University of

    Experimental Investigation of Electron-Acoustic Waves in Electron Plasmas Andrey A. Kabantsev , F Electron-acoustic wave (EAW) solutions of the linearized electrostatic Vlasov equations have usually been USA 92093-0319 Dipt. di Fisica and INFM, Univ. della Calabria, 87036 Rende, Italy Abstract. Electron-acoustic

  13. Roadmap: Electronic Media Electronic Media Sports Production Bachelor of Science

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Electronic Media ­ Electronic Media Sports Production ­ Bachelor of Science [CI­2013 Page 1 of 4 | Last Updated: 23-May-12/LNHD This roadmap is a recommended semester-by-semester plan requirement #12;Roadmap: Electronic Media ­ Electronic Media Sports Production ­ Bachelor of Science [CI

  14. An electronic radiation of blackbody: Cosmic electron background

    E-Print Network [OSTI]

    Jian-Miin Liu

    2008-02-23

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

  15. Electronic Survey Methodology Page 1 Electronic Survey Methodology

    E-Print Network [OSTI]

    Nonnecke, Blair

    Electronic Survey Methodology Page 1 Electronic Survey Methodology: A Case Study in Reaching Hard, Maryland preece@umbc.edu 2002 © Andrews, Nonnecke and Preece #12;Electronic Survey Methodology Page 2 Conducting Research on the Internet: Electronic survey Design, Development and Implementation Guidelines

  16. p-Type semiconducting nickel oxide as an efficiency-enhancing anodal interfacial layer in bulk heterojunction solar cells

    DOE Patents [OSTI]

    Irwin, Michael D; Buchholz, Donald B; Marks, Tobin J; Chang, Robert P. H.

    2014-11-25

    The present invention, in one aspect, relates to a solar cell. In one embodiment, the solar cell includes an anode, a p-type semiconductor layer formed on the anode, and an active organic layer formed on the p-type semiconductor layer, where the active organic layer has an electron-donating organic material and an electron-accepting organic material.

  17. Dark matter vs. astrophysics in the interpretation of AMS-02 electron and positron data

    E-Print Network [OSTI]

    Di Mauro, Mattia; Fornengo, Nicolao; Vittino, Andrea

    2015-01-01

    We perform a detailed quantitative analysis of the recent AMS-02 electron and positron data. We investigate the interplay between the emission from primary astrophysical sources, namely Supernova Remnants and Pulsar Wind Nebulae, and the contribution from a dark matter annihilation or decay signal. Our aim is to assess the information that can be derived on dark matter properties when both dark matter and primary astrophysical sources are assumed to jointly contribute to the leptonic observables measured by the AMS-02 experiment. We investigate both the possibility to set robust constraints on the dark matter annihilation/decay rate and the possibility to look for dark matter signals within realistic models that take into account the full complexity of the astrophysical background. Our results show that AMS-02 data enable to probe efficiently vast regions of the dark matter parameter space and, in some cases, to set constraints on the dark matter annihilation/decay rate that are comparable or even stronger wi...

  18. Tailored electron bunches with smooth current profiles for enhanced transformer ratios in beam-driven acceleration

    E-Print Network [OSTI]

    Lemery, Francois

    2015-01-01

    Collinear high-gradient ${\\cal O} (GV/m)$ beam-driven wakefield methods for charged-particle acceleration could be critical to the realization of compact, cost-efficient, accelerators, e.g., in support of TeV-scale lepton colliders or multiple-user free-electron laser facilities. To make these options viable, the high accelerating fields need to be complemented with large transformer ratios $>2$, a parameter characterizing the efficiency of the energy transfer between a wakefield-exciting "drive" bunch to an accelerated "witness" bunch. While several potential current distributions have been discussed, their practical realization appears challenging due to their often discontinuous nature. In this paper we propose several alternative current profiles which are smooth which also lead to enhanced transformer ratios. We especially explore a laser-shaping method capable of generating one the suggested distributions directly out of a photoinjector and discuss a linac concept that could possible drive a dielectric ...

  19. Search for physics beyond the standard model in events with two leptons, jets, and missing transverse momentum in pp collisions at ?s = 8 TeV

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

    Khachatryan, V.; et al.

    2015-04-22

    A search is presented for physics beyond the standard model in final states with two opposite-sign same-flavor leptons, jets, and missing transverse momentum. The data sample corresponds to an integrated luminosity of 19.4 fb-1 of proton-proton collisions at ?s¯ = 8 TeV collected with the CMS detector at the CERN LHC in 2012. The analysis focuses on searches for a kinematic edge in the invariant mass distribution of the oppositesign same-flavor lepton pair and for final states with an on-shell Z boson. The observations are consistent with expectations from standard model processes and are interpreted in terms of upper limitsmore »on the production of supersymmetric particles.« less

  20. Measurement of $ZZ$ production in leptonic final states at $\\surd{s}$ of 1.96 TeV at CDF

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Texas A-M

    2011-12-01

    In this paper we present a precise measurement of the total ZZ production cross section in p{bar p} collisions at {radical}s = 1.96 TeV, using data collected with the CDF II detector corresponding to an integrated luminosity of approximately 6 fb{sup -1}. The result is obtained by combining separate measurements in the four-charged ({ell}{ell}{ell}{prime}{ell}{prime}), and two-charged-lepton and two-neutral-lepton ({ell}{ell}{nu}{nu}) decay modes of the Z. The combined measured cross section for p{bar p} {yields} ZZ is 1.64{sub -0.38}{sup +0.44} pb. This is the most precise measurement of the ZZ production cross section in 1.96 TeV p{bar p} collisions to date.

  1. Light Vector Meson Photoproduction off of 1H at Jefferson Lab and p-w Interference in the Leptonic Decay Channel

    SciTech Connect (OSTI)

    Djalali, Chaden; Paolone, Michael; Weygand, Dennis; Wood, Mike H.

    2014-09-01

    Although the phenomena of r – w interference has been studied at great length in pionic decay channel over the past 50 years, a study of the interference in a purely electromagnetic production and decay channel has never been performed on an elementary proton target until now. The only published photo-production data of the r - w leptonic decay channel was obtained in the early seventies on C and Be. An investigation of the r - w interference on a Hydrogen was recently completed at Jefferson Lab with the CLAS detector. The di-lepton spectra was fit with two inter- fering relativistic Breit-Wigner functions, and the interference phase was extracted. Preliminary results will be compared to the previous experimental studies in nuclei.

  2. Search for squark production in events with jets, hadronically decaying tau leptons and missing transverse energy at s**(1/2) = 1.96-TeV

    SciTech Connect (OSTI)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /York U., Canada /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-05-01

    A search for supersymmetric partners of quarks is performed in the topology of multijet events accompanied by at least one tau lepton decaying hadronically and large missing transverse energy. Approximately 1 fb-1 of ppbar collision data from the Fermilab Tevatron Collider at a center of mass energy of 1.96 TeV recorded by the D0 detector is analyzed. Results are combined with the previously published D0 inclusive search for squarks and gluinos. No evidence of physics beyond the standard model is found and lower limits on the squark mass up to 410 GeV are derived in the framework of minimal supergravity with tan(beta)=15, A{sub 0}=-2m{sub 0} and mu<0, in the region where decays to tau leptons dominate. Gaugino masses m{sub 1/2} are excluded up to 172 GeV.

  3. Phenomenology of the SU(3){sub c}xSU(3){sub L}xU(1){sub X} model with exotic charged leptons

    SciTech Connect (OSTI)

    Salazar, Juan C.; Ponce, William A.; Gutierrez, Diego A.

    2007-04-01

    A phenomenological analysis of the three-family model based on the local gauge group SU(3){sub c}xSU(3){sub L}xU(1){sub X} with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produce quark and charged lepton mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions to achieve a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model.

  4. Accelerators of ELV-type Status, development, applications

    E-Print Network [OSTI]

    -type accelerator with a foilextraction is givenin Fig.2. Inside the tank lled with the SF6 gas are located: primary and extraction device are xed to the bottom of the tank. Electrons emitted by the cathode, placed on the upper; 29 - magnetic lens; 30 - high voltage shield; 32 - clamp set #12;4 Figure 3: Simpli ed electric

  5. Measurement of Non-photonic Electrons in p + p Collisions at $\\sqrt{s_{NN}}$ = 200 GeV with reduced detector material in STAR

    E-Print Network [OSTI]

    F. Jin; for the STAR Collaboration

    2009-01-06

    In this paper, we present our analysis of mid-rapidity non-photonic electron (NPE) production at pT >0.2GeV/c in p+p collisions at $\\sqrt{s_{NN}}$ = 200 GeV. The dataset is about 78M TOF-triggered events taken from RHIC year 2008 runs. Through the measurement of e/\\pi ratio, we find that the photonic background electrons from gamma conversions are reduced by about a factor of 10 compared with those in STAR previous runs due to the absence of inner tracking detectors and the supporting materials. The dramatic increase of signal-to-background ratio will allow us to improve the precision on extracting the charm cross-section via its semi-leptonic decays to electrons.

  6. Measurement of non-photonic electrons in p+p collisions at sNN = 200 GeV with reduced detector material in STAR

    SciTech Connect (OSTI)

    Jin,F.; Hallman,T.; et al.

    2009-05-13

    In this paper, we present our analysis of mid rapidity non-photonic electron (NPE) production at pT > 0.2 GeV/c in p+p collisions at ?sNN = 200 GeV. The data set is ?78 M TOF-triggered events taken from RHIC year 2008runs. Through the measurement of the e/? ratio, we find that the photonic background electrons from ? conversions are reduced by about a factor of 10 compared with those in STAR previous runs due to the absence of inner tracking detectors and the supporting materials. The dramatic increase of the signal-to-background ratio will allow us to improve the precision on extracting the charm cross section via its semi-leptonic decays to electrons.

  7. Search for anomalous production of events with three or more leptons in pp collisions at sqrt(s) = 8 TeV

    SciTech Connect (OSTI)

    Chatrchyan, S.; et al.,

    2014-08-01

    A search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5 inverse femtobarns of proton-proton collisions with center-of-mass energy sqrt(s) = 8 TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, same-flavor lepton pair (OSSF), the invariant mass of the OSSF pair, the presence or absence of a tagged bottom-quark jet, the number of identified hadronically decaying tau leptons, and the magnitude of the missing transverse energy and of the scalar sum of jet transverse momenta. The numbers of observed events are found to be consistent with the expected numbers from standard model processes, and limits are placed on new-physics scenarios that yield multilepton final states. In particular, scenarios that predict Higgs boson production in the context of supersymmetric decay chains are examined. We also place a 95% confidence level upper limit of 1.3% on the branching fraction for the decay of a top quark to a charm quark and a Higgs boson (t to c H), which translates to a bound on the left- and right-handed top-charm flavor-violating Higgs Yukawa couplings, lambda[H, tc] and lambda[H, ct], respectively, of sqrt(abs(lambda[H, tc])^2 + abs(lambda[H, ct])^2) < 0.21.

  8. Radiation defects in silicon due to hadrons and leptons, their annealing and influence on detector performance

    E-Print Network [OSTI]

    Ionel Lazanu; Sorina Lazanu

    2002-03-25

    A phenomenological model was developed to explain quantitatively, without free parameters, the production of primary defects in silicon after particle irradiation, the kinetics of their evolution toward equilibrium and their influence on detector parameters. The type of the projectile particle and its energy is considered in the evaluation of the concentration of primary defects. Vacancy-interstitial annihilation, interstitial migration to sinks, vacancy - impurity complexes (VP, VO, V2O), and divacancy (V2) formation are taken into account in different irradiation conditions, for different concentrations of impurities in the semiconductor material, for 20 and 0 degrees C. The model can be extended to include other vacancy and interstitial complexes. The density of the reverse current in the detector after irradiation is estimated. Comparison with experimental measurements is performed. A special application considered in the paper is the modelled case of the behaviour of silicon detectors operating in the pion field estimated for the LHC accelerator, under continuum generation and annealing.

  9. Top Quark Mass Measurement in the Lepton plus Jets Channel Using a Modified Matrix Element Method

    SciTech Connect (OSTI)

    Aaltonen, T.; /Helsinki Inst. of Phys.; Adelman, J.; /Chicago U., EFI; Akimoto, T.; /Tsukuba U.; Alvarez Gonzalez, B.; /CSIC, Catalunya; Amerio, S.; /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, A.; /Frascati; Antos, J.; /Comenius U.; Apollinari, G.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U.

    2008-12-01

    The authors report a measurement of the top quark mass, m{sub t}, obtained from p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector. They analyze a sample corresponding to an integrated luminosity of 1.9 rfb{sup -1}. They select events with an electron or muon, large missing transverse energy, and exactly four high-energy jets in the central region of the detector, at least one of which is tagged as coming from a b quark. They calculate a signal likelihood using a matrix element integration method, where the matrix element is modified by using effective propagators to take into account assumptions on event kinematics. The event likelihood is a function of m{sub t} and a parameter JES that determines in situ the calibration of the jet energies. They use a neural network discriminant to distinguish signal from background events. They also apply a cut on the peak value of each event likelihood curve to reduce the contribution of background and badly reconstructed events. Using the 318 events that pass all selection criteria, they find m{sub t} = 172.7 {+-} 1.8 (stat. + JES) {+-} 1.2(syst.) GeV/c{sup 2}.

  10. Foil Electron Multiplier

    DOE Patents [OSTI]

    Funsten, Herbert O. (Los Alamos, NM); Baldonado, Juan R. (Los Alamos, NM); Dors, Eric E. (Los Alamos, NM); Harper, Ronnie W. (Los Alamos, NM); Skoug, Ruth M. (Los Alamos, NM)

    2006-03-28

    An apparatus for electron multiplication by transmission that is designed with at least one foil having a front side for receiving incident particles and a back side for transmitting secondary electrons that are produced from the incident particles transiting through the foil. The foil thickness enables the incident particles to travel through the foil and continue on to an anode or to a next foil in series with the first foil. The foil, or foils, and anode are contained within a supporting structure that is attached within an evacuated enclosure. An electrical power supply is connected to the foil, or foils, and the anode to provide an electrical field gradient effective to accelerate negatively charged incident particles and the generated secondary electrons through the foil, or foils, to the anode for collection.

  11. Self-sustained asymmetry of lepton-number emission: A new phenomenon during the supernova shock-accretion phase in three dimensions

    E-Print Network [OSTI]

    Tamborra, Irene; Janka, Hans-Thomas; Mueller, Bernhard; Raffelt, Georg G; Marek, Andreas

    2014-01-01

    During the stalled-shock phase of our 3D hydrodynamical core-collapse simulations with energy-dependent, 3-flavor neutrino transport, the lepton-number flux (nu_e minus anti-nu_e) emerges predominantly in one hemisphere. This novel, spherical-symmetry breaking neutrino-hydrodynamical instability is termed LESA for "Lepton-number Emission Self-sustained Asymmetry." While the individual nu_e and anti-nu_e fluxes show a pronounced dipole pattern, the heavy-flavor neutrino fluxes and the overall luminosity are almost spherically symmetric. LESA seems to develop stochastically from convective fluctuations, it exists for hundreds of milliseconds or more, and it persists during violent shock sloshing associated with the standing accretion shock instability. The nu_e minus anti-nu_e flux asymmetry originates predominantly below the neutrinosphere in a region of pronounced proto-neutron star (PNS) convection, which is stronger in the hemisphere of enhanced lepton-number flux. On this side of the PNS, the mass-accretio...

  12. Precision electron polarimetry

    SciTech Connect (OSTI)

    Chudakov, Eugene A.

    2013-11-01

    A new generation of precise Parity-Violating experiments will require a sub-percent accuracy of electron beam polarimetry. Compton polarimetry can provide such accuracy at high energies, but at a few hundred MeV the small analyzing power limits the sensitivity. M{\\o}ller polarimetry provides a high analyzing power independent on the beam energy, but is limited by the properties of the polarized targets commonly used. Options for precision polarimetry at ~300 MeV will be discussed, in particular a proposal to use ultra-cold atomic hydrogen traps to provide a 100\\%-polarized electron target for M{\\o}ller polarimetry.

  13. Identification and design principles of low hole effective mass p-type transparent conducting oxides

    E-Print Network [OSTI]

    Hautier, Geoffroy

    The development of high-performance transparent conducting oxides is critical to many technologies from transparent electronics to solar cells. Whereas n-type transparent conducting oxides are present in many devices, their ...

  14. Diamondoid monolayers as electron emitters

    DOE Patents [OSTI]

    Yang, Wanli; Fabbri, Jason D.; Melosh, Nicholas A.; Hussain, Zahid; Shen, Zhi-Xun

    2013-10-29

    Provided are electron emitters based upon diamondoid monolayers, preferably self-assembled higher diamondoid monolayers. High intensity electron emission has been demonstrated employing such diamondoid monolayers, particularly when the monolayers are comprised of higher diamondoids. The application of such diamondoid monolayers can alter the band structure of substrates, as well as emit monochromatic electrons, and the high intensity electron emissions can also greatly improve the efficiency of field-effect electron emitters as applied to industrial and commercial applications.

  15. Diamondoid monolayers as electron emitters

    DOE Patents [OSTI]

    Yang, Wanli (El Cerrito, CA); Fabbri, Jason D. (San Francisco, CA); Melosh, Nicholas A. (Menlo Park, CA); Hussain, Zahid (Orinda, CA); Shen, Zhi-Xun (Stanford, CA)

    2012-04-10

    Provided are electron emitters based upon diamondoid monolayers, preferably self-assembled higher diamondoid monolayers. High intensity electron emission has been demonstrated employing such diamondoid monolayers, particularly when the monolayers are comprised of higher diamondoids. The application of such diamondoid monolayers can alter the band structure of substrates, as well as emit monochromatic electrons, and the high intensity electron emissions can also greatly improve the efficiency of field-effect electron emitters as applied to industrial and commercial applications.

  16. Search for Resonant Top-antitop Production in the Semi-leptonic Decay Mode Using the Full CDF Data Set

    E-Print Network [OSTI]

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

    2013-01-01

    This Letter reports a search for a narrow resonant state decaying into two $W$ bosons and a bottom-antibottom quark pair where one $W$ boson decays leptonically and the other decays into a quark-antiquark pair. The search is particularly sensitive to top-antitop resonant production. We use the full data sample of proton-antiproton collisions at a center-of-mass energy of 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron, corresponding to an integrated luminosity of 9.45 fb$^{-1}$. No evidence for resonant production is found and upper limits on the production cross section times branching ratio for a narrow resonant state are extracted. Within a specific benchmark model, we exclude a $Z'$ boson with mass below 915 GeV/$c^2$ decaying into a top-antitop pair at the 95% credibility level assuming a $Z'$ boson decay width of $\\Gamma_{Z'} = 0.012 M_{Z'}$. This is the most sensitive search for a narrow $\\ensuremath{q\\bar{q}}$-initiated $\\ensuremath{t\\bar{t}}$ resonance in the mass region below 750 ...

  17. Nuclear geometry effect and transport coefficient in semi-inclusive lepton-production of hadrons off nuclei

    E-Print Network [OSTI]

    Na Liu; Wen-Dan Miao; Li-Hua Song; Chun-Gui Duan

    2015-11-03

    Hadron production in semi-inclusive deep-inelastic scattering of leptons from nuclei is an ideal tool to determine and constrain the transport coefficient in cold nuclear matter. The leading-order computations for hadron multiplicity ratios are performed by means of the SW quenching weights and the analytic parameterizations of quenching weights based on BDMPS formalism. The theoretical results are compared to the HERMES positively charged pions production data with the quarks hadronization occurring outside the nucleus. With considering the nuclear geometry effect on hadron production, our predictions are in good agreement with the experimental measurements. The extracted transport parameter from the global fit is shown to be $\\hat{q} = 0.74\\pm0.03 GeV^2/fm$ for the SW quenching weight without the finite energy corrections. As for the analytic parameterization of BDMPS quenching weight without the quark energy E dependence, the computed transport coefficient is $\\hat{q} = 0.20\\pm0.02 GeV^2/fm$. It is found that the nuclear geometry effect has a significant impact on the transport coefficient in cold nuclear matter. It is necessary to consider the detailed nuclear geometry in studying the semi-inclusive hadron production in deep inelastic scattering on nuclear targets.

  18. The role of primary point defects in the degradation of silicon detectors due to hadron and lepton irradiation

    E-Print Network [OSTI]

    I. Lazanu; S. Lazanu

    2006-03-20

    The principal obstacle to long-time operation of silicon detectors at the highest energies in the next generation of experiments arises from bulk displacement damage which causes significant degradation of their macroscopic properties. The analysis of the behaviour of silicon detectors after irradiation conduces to a good or reasonable agreement between theoretical calculations and experimental data for the time evolution of the leakage current and effective carrier concentration after lepton and gamma irradiation and large discrepancies after hadron irradiation and this in conditions where a reasonable agreement is obtained between experimental and calculated concentrations of complex defects. In this contribution, we argue that the main discrepancies could be solved naturally considering as primary defects the self-interstitials, classical vacancies and the new predicted fourfold coordinated silicon pseudo-vacancy defects. This new defect is supposed to be introduced uniformly in the bulk during irradiation, has deep energy level(s) in the gap and it is stable in time. Considering the mechanisms of production of defects and their kinetics, it was possible to determine indirectly the characteristics of the SiFFCD defect: energy level in the band gap and cross section for minority carrier capture. In the frame of the model, the effects of primary defects on the degradation of silicon detectors are important in conditions of continuous long time irradiation and /or high fluences.

  19. Third-frequency-moment sum rule for electronic multilayers

    SciTech Connect (OSTI)

    Lu, Dexin [Department for Intensive Instruction, Nanjing University, Nanjing 210093, People's Republic of China (China)] [Department for Intensive Instruction, Nanjing University, Nanjing 210093, People's Republic of China (China); Golden, Kenneth I. [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401-1455 (United States)] [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401-1455 (United States)

    2000-01-01

    The authors establish the third-frequency-moment sum rules for the density-density response matrix of electronic multilayer structures modeled as an array of N parallel two-dimensional (2D) electron-plasma monolayers. Layer densities and spacings between adjacent layers need not be equal. Contact is made with previously established sum rules for the isolated 2D electron liquid and type-1 infinite superlattices. The case of the equal-density bilayer is considered and its third frequency-moment-sum-rules for the in-phase and out-of-phase inverse dielectric functions are formulated. (c) 2000 The American Physical Society.

  20. Electron-Electron Bremsstrahlung Emission and the Inference of Electron Flux Spectra in Solar Flares

    E-Print Network [OSTI]

    Eduard P. Kontar; A. Gordon Emslie; Anna Maria Massone; Michele Piana; John C. Brown; Marco Prato

    2007-07-28

    Although both electron-ion and electron-electron bremsstrahlung contribute to the hard X-ray emission from solar flares, the latter is normally ignored. Such an omission is not justified at electron (and photon) energies above $\\sim 300$ keV, and inclusion of the additional electron-electron bremsstrahlung in general makes the electron spectrum required to produce a given hard X-ray spectrum steeper at high energies. Unlike electron-ion bremsstrahlung, electron-electron bremsstrahlung cannot produce photons of all energies up to the maximum electron energy involved. The maximum possible photon energy depends on the angle between the direction of the emitting electron and the emitted photon, and this suggests a diagnostic for an upper cutoff energy and/or for the degree of beaming of the accelerated electrons. We analyze the large event of January 17, 2005 observed by RHESSI and show that the upward break around 400 keV in the observed hard X-ray spectrum is naturally accounted for by the inclusion of electron-electron bremsstrahlung. Indeed, the mean source electron spectrum recovered through a regularized inversion of the hard X-ray spectrum, using a cross-section that includes both electron-ion and electron-electron terms, has a relatively constant spectral index $\\delta$ over the range from electron kinetic energy $E = 200$ keV to $E = 1$ MeV. However, the level of detail discernible in the recovered electron spectrum is not sufficient to determine whether or not any upper cutoff energy exists.

  1. Linkping University Electronic Press Electronic Publication of a Thesis with LiU Electronic Press

    E-Print Network [OSTI]

    Zhao, Yuxiao

    Linköping University Electronic Press Electronic Publication of a Thesis with LiU Electronic Press with LiU E-Press. In individual cases where there are complications because of e.g. copyright on the world wide web by Linköping University Electronic Press (www.ep.liu.se). In so doing, I certify

  2. Electronics 2014, 3, 624-635; doi:10.3390/electronics3040624 electronics

    E-Print Network [OSTI]

    Chen, Ray

    Article Towards Realizing High-Throughput, Roll-to-Roll Manufacturing of Flexible Electronic Systems2R) tracker systems are utilized for large volume flexible electronic device manufacturing/min. Keywords: roll-to-roll; ink-jet printing; flexible electronics; alignment OPEN ACCESS #12;Electronics 2014

  3. Linkping University Electronic Press

    E-Print Network [OSTI]

    Zhao, Yuxiao

    Linköping University Electronic Press Strategic Plan 2007-2009 January, 2007 #12;Executive SummaryU E-Press for 2007 to 2009. LiU E-Press currently has a collection of about 350 Ph.D. theses, 120 activities for LiU E-Press between 2007 and 2009: 2007 · Re-design of E-Press' website; · Application

  4. Linkping University Electronic Press

    E-Print Network [OSTI]

    Zhao, Yuxiao

    Linköping University Electronic Press Activity Summary, 2007 January, 2008 1 #12;1. Organization In March of 2007, Erik Sandewall, E-Press' director, resigned in order to take up a position at the Royal solution was found as part of a larger restructuring of LiU E-Press. As of September 1st , the Board

  5. MEIC electron cooling program

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

    Derbenev, Yaroslav S.; Zhang, Yuhong

    2014-12-01

    Cooling of proton and ion beams is essential for achieving high luminosities (up to above 1034 cm-2s-1) for MEIC, a Medium energy Electron-Ion Collider envisioned at JLab [1] for advanced nuclear science research. In the present conceptual design, we utilize the conventional election cooling method and adopted a multi-staged cooling scheme for reduction of and maintaining low beam emittances [2,3,4]. Two electron cooling facilities are required to support the scheme: one is a low energy (up to 2 MeV) DC cooler installed in the MEIC ion pre-booster (with the proton kinetic energy up to 3 GeV); the other is amore »high electron energy (up to 55 MeV) cooler in the collider ring (with the proton kinetic energy from 25 to 100 GeV). The high energy cooler, which is based on the ERL technology and a circulator ring, utilizes a bunched electron beam to cool bunched proton or ion beams. To complete the MEIC cooling concept and a technical design of the ERL cooler as well as to develop supporting technologies, an R&D program has been initiated at Jefferson Lab and significant progresses have been made since then. In this study, we present a brief description of the cooler design and a summary of the progress in this cooling R&D.« less

  6. Inside this issue: Electronics

    E-Print Network [OSTI]

    Alexandrova, Ivana

    On Campus 8 Rain Garden Installed 8 Get involved 9 Energy Campaign Update October 2010 Volume 4, Issue 1Inside this issue: Energy Campaign 1 Electronics Recycling Day 2 Upcoming Events 3 Crew Erases Office of Environmental Sustainability Sustainability Bulletin The Fall 2010 Energy Campaign is currently

  7. Calorimeter Electronics Jim Pilcher

    E-Print Network [OSTI]

    Incident particles deposit their energy in a medium Tank of liquid (water or scintillator), dense medium is produced Electronics converts this signal to digital information For signal processing to calculate-year-old design Now quantum efficiencies over 40% Segmented anodes (eg. 8x8) #12;December 11, 2008 J

  8. Electronics Research Beckman Institute

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    -assembling three-dimensional nanostructure for battery cathodes that enables extremely quick charging and discharging without sacrificing energy storage capacity.The new technology is compatible with current manufacturing methods and ideal for use in consumer electronics, electric vehicles, and medical devices, among

  9. GRAPHENE: ELECTRON PROPERTIES AND

    E-Print Network [OSTI]

    Gabrieli, John

    GRAPHENE: ELECTRON PROPERTIES AND TRANSPORT PHENOMENA Leonid Levitov MIT Lecture notes and HW and magnetoresistance Quantum Hall effect reminder The half-integer QHE in graphene Energy gaps and splitting of Landau levels QHE in p-n and p-n-p junctions Spin transport at graphene edge Fine structure constant

  10. electronic reprint Synchrotron

    E-Print Network [OSTI]

    or its storage in electronic databases or the like is not permitted without prior permission in writing-element speciation. Often, these trace elements are sorbed to clays or phyllomanganates, which are nanostructured as a function of position. Other materials examples include defects in semiconductor devices, which may also

  11. Evolution of the conductivity type in germania by varying the stoichiometry

    SciTech Connect (OSTI)

    Islamov, D. R., E-mail: damir@isp.nsc.ru [A. V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Gritsenko, V. A., E-mail: grits@isp.nsc.ru [A. V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Cheng, C. H. [Department of Mechatronic Technology, National Taiwan Normal University, Taipei 106, Taiwan (China)] [Department of Mechatronic Technology, National Taiwan Normal University, Taipei 106, Taiwan (China); Chin, A., E-mail: albert-achin@hotmail.com [National Chiao Tung University, Hsinchu 300, Taiwan (China)

    2013-12-02

    Information regarding the conductivity type of Si/GeO{sub x}/Ni structures with various stoichiometry has been obtained using experiments on injection of minority carriers from n- and p-type silicon. Results show that non-stoichiometric GeO{sub x} films exhibit bipolar conductivity, that is, holes as well as electrons contribute to the charge transport. Stoichiometric GeO{sub 2} films exhibit unipolar electron conductivity.

  12. The effect of electron-electron interaction induced dephasing on electronic transport in graphene nanoribbons

    SciTech Connect (OSTI)

    Kahnoj, Sina Soleimani; Touski, Shoeib Babaee; Pourfath, Mahdi E-mail: pourfath@iue.tuwien.ac.at

    2014-09-08

    The effect of dephasing induced by electron-electron interaction on electronic transport in graphene nanoribbons is theoretically investigated. In the presence of disorder in graphene nanoribbons, wavefunction of electrons can set up standing waves along the channel and the conductance exponentially decreases with the ribbon's length. Employing the non-equilibrium Green's function formalism along with an accurate model for describing the dephasing induced by electron-electron interaction, we show that this kind of interaction prevents localization and transport of electrons remains in the diffusive regime where the conductance is inversely proportional to the ribbon's length.

  13. Pluggable type-checking for custom type qualifiers in Java

    E-Print Network [OSTI]

    Papi, Matthew M.

    2007-09-17

    We have created a framework for adding custom type qualifiers to the Javalanguage in a backward-compatible way. The type system designer definesthe qualifiers and creates a compiler plug-in that enforces theirsemantics. ...

  14. PICTURE GROUPS OF FINITE TYPE AND COHOMOLOGY IN TYPE An

    E-Print Network [OSTI]

    Igusa, Kiyoshi

    PICTURE GROUPS OF FINITE TYPE AND COHOMOLOGY IN TYPE An KIYOSHI IGUSA, KENT ORR, GORDANA TODOROV a picture group. We construct a finite CW complex which is shown in another paper [10] to be a K(, 1) for this picture group. In [5] another independent proof was given for this fact in the special case of type

  15. Abstract Data Types 5 Algebraic Theory of Abstract Data Types

    E-Print Network [OSTI]

    Berger, Ulrich

    stack top: stack elts The following is an algebra for the signature STACK. Algebra SeqN Carriers N, N43 Part II Abstract Data Types #12;44 5 Algebraic Theory of Abstract Data Types An Abstract Data Type (ADT) is a collection of objects and functions, that is, an algebra, where one ignores how

  16. Mechanism of magnetism in stacked nanographite with open shell electrons

    E-Print Network [OSTI]

    Kikuo Harigaya; Toshiaki Enoki

    2001-10-23

    Antiferromagnetism in stacked nanographite is investigated with using the Hubbard-type models. The A-B stacking or the stacking near to that of A-B type is favorable for the hexagonal nanographite with zigzag edges, in order that magnetism appears. Next, we find that the open shell electronic structure can be an origin of the decreasing magnetic moment with the decrease of the inter-graphene distance, as experiments on adsorption of molecules suggest.

  17. First Measurements of Spin Correlation Using Semi-leptonic $t\\bar{t}$ Events at ATLAS

    E-Print Network [OSTI]

    Boris Lemmer; for the ATLAS Collaboration

    2014-11-20

    The top quark decays before it hadronizes. Before its spin state can be changed in a process of strong interaction, it is directly transferred to the top quark decay products. The top quark spin can be deduced by studying angular distributions of the decay products. The Standard Model predicts the top/anti-top quark ($t\\bar{t}$) pairs to have correlated spins. The degree is sensitive to the spin and the production mechanisms of the top quark. Measuring the spin correlation allows to test the predictions. New physics effects can be reflected in deviations from the prediction. The measurement of the spin correlation of $t\\bar{t}$ pairs, produced at the LHC with a center-of-mass energy of $\\sqrt{s} = 7$ TeV and reconstructed with the ATLAS detector, is presented. The dataset corresponds to an integrated luminosity of 4.6 $\\textrm{fb}^{-1}$. $t\\bar{t}$ pairs are reconstructed in the $\\ell$+jets channel using a kinematic likelihood fit offering the identification of light up- and down-type quarks from the $t \\rightarrow bW \\rightarrow bq\\bar{q}'$ decay. The spin correlation is measured via the distribution of the azimuthal angle $\\Delta \\phi$ between two top quark spin analyzers in the laboratory frame. It is expressed as the degree of $t\\bar{t}$ spin correlation predicted by the Standard Model, $f_{\\textrm{SM}}$. The result of $f_{\\textrm{SM}}= 1.12 \\pm 0.11\\,\\text{(stat.)} \\pm 0.22\\,\\text{(syst.)}$ is consistent with the Standard Model prediction of $f_{\\textrm{SM}}= 1.0$.

  18. Electronic structure and transport in molecular and nanoscale electronics

    E-Print Network [OSTI]

    Qian, Xiaofeng

    2008-01-01

    Two approaches based on first-principles method are developed to qualitatively and quantitatively study electronic structure and phase-coherent transport in molecular and nanoscale electronics, where both quantum mechanical ...

  19. Approved Module Information for EE2DPS, 2014/5 Module Title/Name: Digital and Programmable Electronic

    E-Print Network [OSTI]

    Neirotti, Juan Pablo

    Electronic Systems Module Code: EE2DPS School: Engineering and Applied Science Module Type: Standard Module (Foundation Degree/Dip He) Programmes in which available: BEng Electrical and Electronic Engineering. BEng Communications Engineering. BEng Electronic Engineering and Computer Science. BEng Electrical Engineering Systems

  20. Electron standing waves on the Si,,111...-3 3-Ag surface Norio Sato and Sakura Takeda

    E-Print Network [OSTI]

    Hasegawa, Shuji

    Electron standing waves on the Si,,111...- 3 3-Ag surface Norio Sato and Sakura Takeda Department-0012, Japan Received 2 July 1998 Electron standing waves have been observed near step edges and out as a potential barrier for the surface-state electrons to make the standing waves, while the other type does not