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Author (up) del Rio, A.; Navarro-Salas, J. url  doi
openurl 
  Title Spacetime correlators of perturbations in slow-roll de Sitter inflation Type Journal Article
  Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 89 Issue 8 Pages 084037 - 7pp  
  Keywords  
  Abstract Two-point correlators and self-correlators of primordial perturbations in quasi-de Sitter spacetime backgrounds are considered. For large separations two-point correlators exhibit nearly scale invariance, while for short distances self-correlators need standard renormalization. We study the deformation of two-point correlators to smoothly match the self-correlators at coincidence. The corresponding angular power spectrum is evaluated in the Sachs-Wolfe regime of low multipoles. Scale invariance is maintained, but the amplitude of C(l)could change in a nontrivial way.  
  Address [del Rio, Adrian] Univ Valencia, Fac Fis, Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, E-46100 Valencia, Spain  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000334335200008 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1768  
Permanent link to this record
 
 
Author (up) del Rio, A.; Navarro-Salas, J.; Torrenti, F. url  doi
openurl 
  Title Renormalized stress-energy tensor for spin-1/2 fields in expanding universes Type Journal Article
  Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 90 Issue 8 Pages 084017 - 15pp  
  Keywords  
  Abstract We provide an explicit expression for the renormalized expectation value of the stress-energy tensor of a spin-1/2 field in a spatially flat Friedmann-Lemaitre-Robertson-Walker universe. Its computation is based on the extension of the adiabatic regularization method to fermion fields introduced recently in the literature. The tensor is given in terms of UV-finite integrals in momentum space, which involve the mode functions that define the quantum state. As illustrative examples of the method efficiency, we see how to compute the renormalized energy density and pressure in two interesting cosmological scenarios: a de Sitter spacetime and a radiation-dominated universe. In the second case, we explicitly show that the late-time renormalized stress-energy tensor behaves as that of classical cold matter. We also check that, if we obtain the adiabatic expansion of the scalar field mode functions with a similar procedure to the one used for fermions, we recover the well-known WKB-type expansion.  
  Address [del Rio, Adrian; Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, E-46100 Burjassot, Valencia, Spain, Email: adrian.rio@uv.es;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000343773100003 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1985  
Permanent link to this record
 
 
Author (up) Della Morte, M.; Dooling, S.; Heitger, J.; Hesse, D.; Simma, H. url  doi
openurl 
  Title Matching of heavy-light flavour currents between HQET at order 1/m and QCD: I. Strategy and tree-level study Type Journal Article
  Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 05 Issue 5 Pages 060 - 31pp  
  Keywords Lattice Gauge Field Theories; B-Physics; Heavy Quark Physics  
  Abstract We present a strategy how to match the full set of components of the heavy-light axial and vector currents in Heavy Quark Effective Theory (HQET), up to and including 1/m (h) -corrections, to QCD. While the ultimate goal is to apply these matching conditions non-perturbatively, in this study we first have implemented them at tree-level, in order to find good choices of the matching observables with small contributions. They can later be employed in the non-perturbative matching procedure which is a crucial part of precision HQET computations of semileptonic decay form factors in lattice QCD.  
  Address [Della Morte, Michele] Inst Fis Corpuscular IFIC CSIC, E-46980 Paterna, Spain, Email: dellamor@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000336406000001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1795  
Permanent link to this record
 
 
Author (up) DELPHI Collaboration (Abdallah, J. et al); Costa, M.J.; Ferrer, A.; Fuster, J.; Garcia, C.; Oyanguren, A.; Perepelitsa, V.; Salt, J.; Tortosa, P. doi  openurl
  Title Measurement of the electron structure function F-2(e) at LEP energies Type Journal Article
  Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 737 Issue Pages 39-47  
  Keywords  
  Abstract The hadronic part of the electron structure function F-2(e) has been measured for the first time, using e(+)e(-) data collected by the DELPHI experiment at LEP, at centre-of-mass energies of root s = 91.2-209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F-2(e) data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F-2(gamma) analyses and help in refining existing parameterizations.  
  Address [Lamsa, J.] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000342757700008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1965  
Permanent link to this record
 
 
Author (up) Deppisch, F.F.; Desai, N.; Valle, J.W.F. url  doi
openurl 
  Title Is charged lepton flavor violation a high energy phenomenon? Type Journal Article
  Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 89 Issue 5 Pages 051302 - 5pp  
  Keywords  
  Abstract Searches for rare processes such as μ-> e gamma put stringent limits on lepton flavor violation expected in many beyond-the-Standard-Model physics scenarios. This usually precludes the observation of flavor violation at high energy colliders such as the LHC. We here discuss a scenario where right-handed neutrinos are produced via a Z' portal but which can only decay via small flavor violating couplings. Consequently, the process rate is unsuppressed by the small couplings and can be visible despite unobservably small μ-> e gamma rates.  
  Address [Deppisch, Frank F.; Desai, Nishita] UCL, Dept Phys & Astron, London WC1E 6BT, England, Email: f.deppisch@ucl.ac.uk;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000334304700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1774  
Permanent link to this record
 
 
Author (up) Deppisch, F.F.; Harz, J.; Hirsch, M. url  doi
openurl 
  Title Falsifying High-Scale Leptogenesis at the LHC Type Journal Article
  Year 2014 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.  
  Volume 112 Issue 22 Pages 221601 - 5pp  
  Keywords  
  Abstract Measuring a nonzero value for the cross section of any lepton number violating (LNV) process would put a strong lower limit on the washout factor for the effective lepton number density in the early Universe at times close to the electroweak phase transition and thus would lead to important constraints on any high-scale model for the generation of the observed baryon asymmetry based on LNV. In particular, for leptogenesis (LG) models with masses of the right-handed neutrinos heavier than the mass scale observed at the LHC, the implied large washout factors would lead to a violation of the out-of-equilibrium condition and exponentially suppress the net lepton number produced in such LG models. We thus demonstrate that the observation of LNV processes at the LHC results in the falsification of high-scale LG models. However, no conclusions about the viability of LG models can be drawn from the nonobservation of LNV processes.  
  Address [Deppisch, Frank F.; Harz, Julia] UCL, Dept Phys & Astron, London WC1E 6BT, England, Email: f.deppisch@ucl.ac.uk;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000336920800003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1816  
Permanent link to this record
 
 
Author (up) Di Mauro, M.; Donato, F.; Fornengo, N.; Lineros, R.A.; Vittino, A. url  doi
openurl 
  Title Interpretation of AMS-02 electrons and positrons data Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 04 Issue 4 Pages 006 - 33pp  
  Keywords ultra high energy cosmic rays; particle acceleration; cosmic ray theory; cosmic ray experiments  
  Abstract We perform a combined analysis of the recent AMS-02 data on electrons, positrons, electrons plus positrons and positron fraction, in a self-consistent framework where we realize a theoretical modeling of all the astrophysical components that can contribute to the observed fluxes in the whole energy range. The primary electron contribution is modeled through the sum of an average flux from distant sources and the fluxes from the local supernova remnants in the Green catalog. The secondary electron and positron fluxes originate from interactions on the interstellar medium of primary cosmic rays, for which we derive a novel determination by using AMS-02 proton and helium data. Primary positrons and electrons from pulsar wind nebulae in the ATNF catalog are included and studied in terms of their most significant (while loosely known) properties and under different assumptions (average contribution from the whole catalog, single dominant pulsar, a few dominant pulsars). We obtain a remarkable agreement between our various modeling and the AMS-02 data for all types of analysis, demonstrating that the whole AMS-02 leptonic data admit a self-consistent interpretation in terms of astrophysical contributions.  
  Address [Di Mauro, M.; Donato, F.; Fornengo, N.; Vittino, A.] Univ Turin, Dipartimento Fis, I-10125 Turin, Italy, Email: mattia.dimauro@to.infn.it;  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1475-7516 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000334496500006 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1771  
Permanent link to this record
 
 
Author (up) Di Valentino, E.; Giusarma, E.; Lattanzi, M.; Melchiorri, A.; Mena, O. url  doi
openurl 
  Title Axion cold dark matter: Status after Planck and BICEP2 Type Journal Article
  Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 90 Issue 4 Pages 043534 - 11pp  
  Keywords  
  Abstract We investigate the axion dark matter scenario (ADM), in which axions account for all of the dark matter in the Universe, in light of the most recent cosmological data. In particular, we use the Planck temperature data, complemented by WMAP E-polarization measurements, as well as the recent BICEP2 observations of B-modes. Baryon acoustic oscillation data, including those from the baryon oscillation spectroscopic survey, are also considered in the numerical analyses. We find that, in the minimal ADM scenario and for Delta(QCD) = 200 MeV, the full data set implies that the axion mass m(a) = 82.2 +/- 1.1 μeV [corresponding to the Peccei-Quinn symmetry being broken at a scale f(a) = (7.54 +/- 0.10) x 10(10) GeV], or m(a) = 76.6 +/- 2.6 μeV [f(a) = (8.08 +/- 0.27) x 10(10) GeV] when we allow for a nonstandard effective number of relativistic species N-eff. We also find a 2 sigma preference for N-eff > 3.046. The limit on the sum of neutrino masses is Sigma m(v) < 0.25 eV at 95% C.L. for N-eff = 3.046, or Sigma m(v) < 0.47 eV when N-eff is a free parameter. Considering extended scenarios where either the dark energy equation-of-state parameter w, the tensor spectral index n(t), or the running of the scalar index dn(s)/d ln k is allowed to vary does not change significantly the axion mass-energy density constraints. However, in the case of the full data set exploited here, there is a preference for a nonzero tensor index or scalar running, driven by the different tensor amplitudes implied by the Planck and BICEP2 observations. We also study the effect on our estimates of theoretical uncertainties, in particular the imprecise knowledge of the QCD scale Delta(QCD), in the calculation of the temperature-dependent axion mass. We find that in the simplest ADM scenario the Planck + WP data set implies that the axion mass m(a) = 63.7 +/- 1.2 μeV for Delta(QCD) = 400 MeV. We also comment on the possibility that axions do not make up for all the dark matter, or that the contribution of string-produced axions has been grossly underestimated; in that case, the values that we find for the mass can conservatively be considered as lower limits. Dark matter axions with mass in the 60-80 μeV (corresponding to an axion-photon coupling G(a gamma gamma) similar to 10(-14) GeV-1) range can, in principle, be detected by looking for axion-to-photon conversion occurring inside a tunable microwave cavity permeated by a high-intensity magnetic field, and operating at a frequency nu similar or equal to 15-20 GHz. This is out of the reach of current experiments like the axion dark matter experiment (limited to a maximum frequency of a few GHzs), but is, on the other hand, within the reach of the upcoming axion dark matter experiment-high frequency experiment that will explore the 4-40 GHz frequency range and then be sensitive to axion masses up to similar to 160 μeV.  
  Address [Di Valentino, Eleonora; Giusarma, Elena; Melchiorri, Alessandro] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000340890100001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1893  
Permanent link to this record
 
 
Author (up) Diamanti, R.; Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Vincent, A.C. url  doi
openurl 
  Title Constraining dark matter late-time energy injection: decays and p-wave annihilations Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 02 Issue 2 Pages 017 - 24pp  
  Keywords dark matter theory; CMBR theory  
  Abstract We use the latest cosmic microwave background (CMB) observations to provide updated constraints on the dark matter lifetime as well as on p-wave suppressed annihilation cross sections in the 1 MeV to 1 TeV mass range. In contrast to scenarios with an s-wave dominated annihilation cross section, which mainly affect the CMB close to the last scattering surface, signatures associated with these scenarios essentially appear at low redshifts (z less than or similar to 50) when structure began to form, and thus manifest at lower multipoles in the CMB power spectrum. We use data from Planck, WMAP9, SPT and ACT, as well as Lyman-alpha measurements of the matter temperature at z similar to 4 to set a 95% confidence level lower bound on the dark matter lifetime of similar to 4 x 10(25) s for m(chi) = 100 MeV. This bound becomes lower by an order of magnitude at m(chi) = 1 TeV due to inefficient energy deposition into the inter-galactic medium. We also show that structure formation can enhance the effect of p-wave suppressed annihilation cross sections by many orders of magnitude with respect to the background cosmological rate, although even with this enhancement, CMB constraints are not yet strong enough to reach the thermal relic value of the cross section.  
  Address [Diamanti, Roberta; Mena, Olga; Palomares-Ruiz, Sergio; Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: R.Diamanti@uva.nl;  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1475-7516 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000332711400017 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1732  
Permanent link to this record
 
 
Author (up) Diez, S. et al; Bernabeu Verdú, J.; Civera, J.V.; Garcia, C.; Garcia-Argos, C.; Lacasta, C.; Marco, R.; Marti-Garcia, S.; Santoyo, D.; Soldevila, U. doi  openurl
  Title A double-sided, shield-less stave prototype for the ATLAS Upgrade strip tracker for the High Luminosity LHC Type Journal Article
  Year 2014 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 9 Issue Pages P03012 - 16pp  
  Keywords Large detector-systems performance; Si microstrip and pad detectors; Particle tracking detectors; Performance of High Energy Physics Detectors  
  Abstract A detailed description of the integration structures for the barrel region of the silicon strips tracker of the ATLAS Phase-II upgrade for the upgrade of the Large Hadron Collider, the so-called High Luminosity LHC (HL-LHC), is presented. This paper focuses on one of the latest demonstrator prototypes recently assembled, with numerous unique features. It consists of a shortened, shield-less, and double sided stave, with two candidate power distributions implemented. Thermal and electrical performances of the prototype are presented, as well as a description of the assembly procedures and tools.  
  Address [Diez, S.; Haber, C. H.; Witharm, R.] LBNL, Berkeley, CA 94103 USA, Email: sdiezcornell@lbl.gov  
  Corporate Author Thesis  
  Publisher Iop Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000336123200072 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1802  
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