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Author XENON100 Collaboration (Aprile, E. et al); Orrigo, S.E.A. url  doi
openurl 
  Title Observation and applications of single-electron charge signals in the XENON100 experiment Type Journal Article
  Year 2014 Publication Journal of Physics G Abbreviated Journal J. Phys. G  
  Volume 41 Issue 3 Pages 035201 - 13pp  
  Keywords xenon; single electron; photoionization; double phase TPC  
  Abstract The XENON100 dark matter experiment uses liquid xenon in a time projection chamber (TPC) to measure xenon nuclear recoils resulting from the scattering of dark matter weakly interacting massive particles (WIMPs). In this paper, we report the observation of single-electron charge signals which are not related to WIMP interactions. These signals, which show the excellent sensitivity of the detector to small charge signals, are explained as being due to the photoionization of impurities in the liquid xenon and of the metal components inside the TPC. They are used as a unique calibration source to characterize the detector. We explain how we can infer crucial parameters for the XENON100 experiment: the secondary-scintillation gain, the extraction yield from the liquid to the gas phase and the electron drift velocity.  
  Address [Aprile, E.; Budnik, R.; Choi, B.; Contreras, H.; Giboni, K-L; Goetzke, L. W.; Lim, K. E.; Fernandez, A. J. Melgarejo; Messina, M.; Plante, G.; Rizzo, A.] Columbia Univ, Dept Phys, New York, NY 10027 USA, Email: jacob.lamblin@lpsc.in2p3.fr;  
  Corporate Author Thesis  
  Publisher (up) 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 0954-3899 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000331865800012 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1959  
Permanent link to this record
 

 
Author Bernal, N.; Forero-Romero, J.E.; Garani, R.; Palomares-Ruiz, S. url  doi
openurl 
  Title Systematic uncertainties from halo asphericity in dark matter searches Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 09 Issue 9 Pages 004 - 30pp  
  Keywords dark matter theory; dark matter simulations  
  Abstract Although commonly assumed to be spherical, dark matter halos are predicted to be non-spherical by N-body simulations and their asphericity has a potential impact on the systematic uncertainties in dark matter searches. The evaluation of these uncertainties is the main aim of this work, where we study the impact of aspherical dark matter density distributions in Milky-Way-like halos on direct and indirect searches. Using data from the large N-body cosmological simulation Bolshoi, we perform a statistical analysis and quantify the systematic uncertainties on the determination of local dark matter density and the so-called J factors for dark matter annihilations and decays from the galactic center. We find that, due to our ignorance about the extent of the non-sphericity of the Milky Way dark matter halo, systematic uncertainties can be as large as 35%, within the 95% most probable region, for a spherically averaged value for the local density of 0.3-0.4 GeV/cm(3). Similarly, systematic uncertainties on the J factors evaluated around the galactic center can be as large as 10% and 15%, within the 95% most probable region, for dark matter annihilations and decays, respectively.  
  Address [Bernal, Nicolas] Univ Estadual Paulista, Inst Fis Teor, ICTP South Amer Inst Fundamental Res, BR-01405 Sao Paulo, Brazil, Email: nicolas@ift.unesp.br;  
  Corporate Author Thesis  
  Publisher (up) 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:000342642500005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1958  
Permanent link to this record
 

 
Author Pallis, C. url  doi
openurl 
  Title Linking Starobinsky-type inflation in no-scale supergravity to MSSM Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 04 Issue 4 Pages 024 - 31pp  
  Keywords particle physics – cosmology connection; supersymmetry and cosmology; cosmology of theories beyond the SM; inflation  
  Abstract A novel realization of the Starobinsky inflationary model within a moderate extension of the Minimal Supersymmetric Standard Model (MSSM) is presented. The proposed superpotential is uniquely determined by applying a continuous R and a Z2 discrete symmetry, whereas the Kahler potential is associated with a no-scale-type SU(54, 1)/ SU(54) x U(1) R X Z2 Kahler manifold. The inflaton is identified with a Higgs-like modulus whose the vacuum expectation value controls the gravitational strength. Thanks to a strong enough coupling (with a parameter CT involved) between the inflaton and the Ricci scalar curvature, inflation can be attained even for subplanckian values of the inflaton with CT >= 76 and the corresponding effective theory being valid up to the Planck scale. The inflationary observables turn out to be in agreement with the current data and the inflaton mass is predicted to be 3 10(3) GeV. At the cost of a relatively small superpotential coupling constant, the model offers also a resolution of the f,t problem of MSSM for CT <= 4500 and gravitino heavier than about 10(4) GeV. Supplementing MSSM by three right-handed neutrinos we show that spontaneously arising couplings between the inflaton and the particle content of MSSM not only ensure a sufficiently low reheating temperature but also support a scenario of non-thermal leptogenesis consistently with the neutrino oscillation parameters.  
  Address [Pallis, C.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: kpallis@auth.gr  
  Corporate Author Thesis  
  Publisher (up) 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:000343042800006 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1961  
Permanent link to this record
 

 
Author Vincent, A.C.; Scott, P. url  doi
openurl 
  Title Thermal conduction by dark matter with velocity and momentum-dependent cross-sections Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 04 Issue 4 Pages 019 - 31pp  
  Keywords dark matter theory; stars  
  Abstract We use the formalism of Gould and Raffelt [1] to compute the dimensionless thermal conduction coefficients for scattering of dark matter particles with standard model nucleons via cross-sections that depend on the relative velocity or momentum exchanged between particles. Motivated by models invoked to reconcile various recent results in direct detection, we explicitly compute the conduction coefficients alpha and kappa for cross-sections that go as v(rel)(2), v(rel)(4), v(rel)(-2), q(2), q(4) and q(-2), where v(rel) is the relative DM-nucleus velocity and q is the momentum transferred in the collision. We find that a v(rel)(-2) depend ence can significantly enhance energy transport from the inner solar core to the outer core. The same can true for any q-dependent coupling, if the dark matter mass lies within some specific range for each coupling. This effect can complement direct searches for dark matter; combining these results with state-of-the-art solar simulations should greatly increase sensitivity to certain DM models. It also seems possible that the so-called Solar Abundance Problem could be resolved by enhanced energy transport in the solar core due to such velocity-or momentum-dependent scatterings.  
  Address [Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: vincent@ific.uv.es;  
  Corporate Author Thesis  
  Publisher (up) 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:000343042800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1962  
Permanent link to this record
 

 
Author Brzezinski, K.; Oliver, J.F.; Gillam, J.; Rafecas, M. doi  openurl
  Title Study of a high-resolution PET system using a Silicon detector probe Type Journal Article
  Year 2014 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.  
  Volume 59 Issue 20 Pages 6117-6140  
  Keywords PET; high-resolution imaging; Si detectors; PET insert  
  Abstract A high-resolution silicon detector probe, in coincidence with a conventional PET scanner, is expected to provide images of higher quality than those achievable using the scanner alone. Spatial resolution should improve due to the finer pixelization of the probe detector, while increased sensitivity in the probe vicinity is expected to decrease noise. A PET-probe prototype is being developed utilizing this principle. The system includes a probe consisting of ten layers of silicon detectors, each a 80 x 52 array of 1 x 1 x 1 mm(3) pixels, to be operated in coincidence with a modern clinical PET scanner. Detailed simulation studies of this system have been performed to assess the effect of the additional probe information on the quality of the reconstructed images. A grid of point sources was simulated to study the contribution of the probe to the system resolution at different locations over the field of view (FOV). A resolution phantom was used to demonstrate the effect on image resolution for two probe positions. A homogeneous source distribution with hot and cold regions was used to demonstrate that the localized improvement in resolution does not come at the expense of the overall quality of the image. Since the improvement is constrained to an area close to the probe, breast imaging is proposed as a potential application for the novel geometry. In this sense, a simplified breast phantom, adjacent to heart and torso compartments, was simulated and the effect of the probe on lesion detectability, through measurements of the local contrast recovery coefficient-to-noise ratio (CNR), was observed. The list-mode ML-EM algorithm was used for image reconstruction in all cases. As expected, the point spread function of the PET-probe system was found to be non-isotropic and vary with position, offering improvement in specific regions. Increase in resolution, of factors of up to 2, was observed in the region close to the probe. Images of the resolution phantom showed visible improvement in resolution when including the probe in the simulations. The image quality study demonstrated that contrast and spill-over ratio in other areas of the FOV were not sacrificed for this enhancement. The CNR study performed on the breast phantom indicates increased lesion detectability provided by the probe.  
  Address [Brzezinski, K.; Oliver, J. F.; Gillam, J.; Rafecas, M.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Valencia, Spain, Email: brzezinski@ific.uv.es  
  Corporate Author Thesis  
  Publisher (up) 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 0031-9155 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000343092300011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1963  
Permanent link to this record
 

 
Author ATLAS Collaboration (Aad, G. et al); Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; March, L.; Marti-Garcia, S.; Mitsou, V.A.; Moles-Valls, R.; Oliver Garcia, E.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Vos, M. url  doi
openurl 
  Title A neural network clustering algorithm for the ATLAS silicon pixel detector Type Journal Article
  Year 2014 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 9 Issue Pages P09009 - 34pp  
  Keywords Particle tracking detectors; Particle tracking detectors (Solid-state detectors)  
  Abstract A novel technique to identify and split clusters created by multiple charged particles in the ATLAS pixel detector using a set of artificial neural networks is presented. Such merged clusters are a common feature of tracks originating from highly energetic objects, such as jets. Neural networks are trained using Monte Carlo samples produced with a detailed detector simulation. This technique replaces the former clustering approach based on a connected component analysis and charge interpolation. The performance of the neural network splitting technique is quantified using data from proton-proton collisions at the LHC collected by the ATLAS detector in 2011 and from Monte Carlo simulations. This technique reduces the number of clusters shared between tracks in highly energetic jets by up to a factor of three. It also provides more precise position and error estimates of the clusters in both the transverse and longitudinal impact parameter resolution.  
  Address [Jackson, P.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia  
  Corporate Author Thesis  
  Publisher (up) 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:000343281300046 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1972  
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. url  doi
openurl 
  Title Observation of charmonium pairs produced exclusively in pp collisions Type Journal Article
  Year 2014 Publication Journal of Physics G Abbreviated Journal J. Phys. G  
  Volume 41 Issue 11 Pages 115002 - 17pp  
  Keywords QCD; diffraction; charmonia  
  Abstract A search is performed for the central exclusive production of pairs of charmonia produced in proton-proton collisions. Using data corresponding to an integrated luminosity of 3 fb(-1) collected at centre-of-mass energies of 7 and 8 TeV, J/psi J/psi and J/psi psi (2S) pairs are observed, which have been produced in the absence of any other activity inside the LHCb acceptance that is sensitive to charged particles in the pseudorapidity ranges (-3.5,-1.5) and (1.5, 5.0). Searches are also performed for pairs of P-wave charmonia and limits are set on their production. The cross-sections for these processes, where the dimeson system has a rapidity between 2.0 and 4.5, are measured to be sigma (J/psi J/psi) = 58 +/- 10(stat) +/- 6(syst) pb, sigma(J/psi psi(2S)) = 63(-18)(+27)(stat) +/- 10(syst) pb, sigma(psi(2S)psi(2S)) < 237 pb, sigma(chi)(chi)(C0)(C0) < 69 nb, sigma(chi)(chi)(C1)(C1) < 45 pb, sigma(chi)(chi)(C2)(C2) < 141 pb, where the upper limits are set at the 90% confidence level. The measured J/psi J/psi and J/psi psi (2S) cross-sections are consistent with theoretical expectations.  
  Address [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Gomes, A.; Hicheur, A.; Massafferri, A.; Rodrigues, B. Osorio; dos Reis, A. C.; Rodrigues, A. B.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: ronan.mcnulty@ucd.ie  
  Corporate Author Thesis  
  Publisher (up) 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 0954-3899 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000344090500011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1992  
Permanent link to this record
 

 
Author LHCb Collaboration (Aaij, R. et al); Martinez-Vidal, F.; Oyanguren, A.; Ruiz Valls, P.; Sanchez Mayordomo, C. url  doi
openurl 
  Title Precision luminosity measurements at LHCb Type Journal Article
  Year 2014 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 9 Issue Pages P12005 - 91pp  
  Keywords Pattern recognition, cluster finding, calibration and fitting methods; Instrumentation for particle accelerators and storage rings – high energy (linear accelerators, synchrotrons)  
  Abstract Measuring cross-sections at the LHC requires the luminosity to be determined accurately at each centre-of-mass energy root s. In this paper results are reported from the luminosity calibrations carried out at the LHC interaction point 8 with the LHCb detector for root s = 2.76, 7 and 8TeV (proton-proton collisions) and for root s(NN) = 5TeV (proton-lead collisions). Both the “van der Meer scan” and “beam-gas imaging” luminosity calibration methods were employed. It is observed that the beam density profile cannot always be described by a function that is factorizable in the two transverse coordinates. The introduction of a two-dimensional description of the beams improves significantly the consistency of the results. For proton-proton interactions at root s = 8TeV a relative precision of the luminosity calibration of 1.47% is obtained using van der Meer scans and 1.43% using beam-gas imaging, resulting in a combined precision of 1.12%. Applying the calibration to the full data set determines the luminosity with a precision of 1.16%. This represents the most precise luminosity measurement achieved so far at a bunched-beam hadron collider.  
  Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Gomes, A.; Hicheur, A.; Massafferri, A.; dos Reis, A. C.; Rodrigues, A. B.] CBPF, Rio De Janeiro, Brazil, Email: rosen.matev@cern.ch  
  Corporate Author Thesis  
  Publisher (up) 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:000345859200021 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2030  
Permanent link to this record
 

 
Author Pujades, M.C.; Granero, D.; Vijande, J.; Ballester, F.; Perez-Calatayud, J.; Papagiannis, P.; Siebert, F.A. doi  openurl
  Title Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities Type Journal Article
  Year 2014 Publication Journal of Radiological Protection Abbreviated Journal J. Radiol. Prot.  
  Volume 34 Issue 4 Pages 741-753  
  Keywords bunker; shielding; NCRP 151; brachytherapy; Monte Carlo  
  Abstract In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for Ir-192 and Co-60 HDR applications to account for several different bunker layouts. For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by Ir-192 and Co-60 will reduce the lead thickness by a factor of five for Ir-192 and ten for Co-60. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers. The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness.  
  Address [Pujades, M. C.] Natl Ctr Dosimetry CND, Valencia, Spain, Email: mpuclau@gmail.com  
  Corporate Author Thesis  
  Publisher (up) 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 0952-4746 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000345895800005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2031  
Permanent link to this record
 

 
Author ANTARES Collaboration (Adrian-Martinez, S. et al); Barrios-Marti, J.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Lambard, G.; Mangano, S.; Sanchez-Losa, A.; Tonnis, C.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Constraining the neutrino emission of gravitationally lensed Flat-Spectrum Radio Quasars with ANTARES data Type Journal Article
  Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 11 Issue 11 Pages 017 - 12pp  
  Keywords gravitational lensing; neutrino astronomy  
  Abstract This paper proposes to exploit gravitational lensing effects to improve the sensitivity of neutrino telescopes to the intrinsic neutrino emission of distant blazar populations. This strategy is illustrated with a search for cosmic neutrinos in the direction of four distant and gravitationally lensed Flat-Spectrum Radio Quasars. The magnification factor is estimated for each system assuming a singular isothermal profile for the lens. Based on data collected from 2007 to 2012 by the ANTARES neutrino telescope, the strongest constraint is obtained from the lensed quasar B0218+357, providing a limit on the total neutrino luminosity of this source of 1.08 x 10(46) erg s(-1) This limit is about one order of magnitude lower than those previously obtained in the ANTARES standard point source searches with non-lensed Flat-Spectrum Radio Quasars.  
  Address [Adrian-Martinez, S.; Ardid, M.; Bou-Cabo, M.; Fells, I.; Herrero, A.; Martinez-Mora, J. A.; Saldana, M.] Univ Politecn Valencia, Inst Invest Gestio Integrada Zones Costaneres IGI, Gandia 46730, Spain  
  Corporate Author Thesis  
  Publisher (up) 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:000346105300018 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2038  
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