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Author Andricek, L. et al; Lacasta, C.; Marinas, C.; Vos, M. doi  openurl
  Title (up) Intrinsic resolutions of DEPFET detector prototypes measured at beam tests Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 638 Issue 1 Pages 24-32  
  Keywords Silicon pixel detector; Detector resolution; Spatial resolution; DEPFET; Beam test  
  Abstract The paper is based on the data of the 2009 DEPFET beam test at CERN SPS. The beam test used beams of pions and electrons with energies between 40 and 120 GeV, and the sensors tested were prototypes with thickness of 450 μm and pixel pitch between 20 and 32 μm. Intrinsic resolutions of the detectors are calculated by disentangling the contributions of measurement errors and multiple scattering in tracking residuals. Properties of the intrinsic resolution estimates and factors that influence them are discussed. For the DEPFET detectors in the beam test, the calculation yields intrinsic resolutions of approximate to 1 μm, with a typical accuracy of 0.1 μm. Bias scan, angle scan, and energy scan are used as example studies to show that the intrinsic resolutions are a useful tool in studies of detector properties. With sufficiently precise telescopes, detailed resolution maps can be constructed and used to study and optimize detector performance.  
  Address [Dolezal, Z.; Drasal, Z.; Kodys, P.; Kvasnicka, P.; Malina, L.; Scheirich, J.] Charles Univ Prague, Fac Math & Phys, Inst Particle & Nucl Phys, CR-18000 Prague, Czech Republic, Email: peter.kodys@mff.cuni.cz  
  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 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000290082600005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 618  
Permanent link to this record
 

 
Author Gomez-Cadenas, J.J.; Benlloch-Rodriguez, J.M.; Ferrario, P.; Monrabal, F.; Rodriguez, J.; Toledo, J.F. url  doi
openurl 
  Title (up) Investigation of the coincidence resolving time performance of a PET scanner based on liquid xenon: a Monte Carlo study Type Journal Article
  Year 2016 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 11 Issue Pages P09011 - 18pp  
  Keywords Gamma camera; SPECT; PET PET/CT; coronary CT angiography (CTA); Instrumentation and methods for time-of-flight (TOF) spectroscopy; Noble liquid detectors (scintillation ionization, double-phase); Scintillators; scintillation and light emission processes (solid, gas and liquid scintillators)  
  Abstract The measurement of the time of flight of the two 511 keV gammas recorded in coincidence in a PET scanner provides an effective way of reducing the random background and therefore increases the scanner sensitivity, provided that the coincidence resolving time (CRT) of the gammas is sufficiently good. The best commercial PET-TOF system today (based in LYSO crystals and digital SiPMs), is the VEREOS of Philips, boasting a CRT of 316 ps (FWHM). In this paper we present a Monte Carlo investigation of the CRT performance of a PET scanner exploiting the scintillating properties of liquid xenon. We find that an excellent CRT of 70 ps (depending on the PDE of the sensor) can be obtained if the scanner is instrumented with silicon photomultipliers (SiPMs) sensitive to the ultraviolet light emitted by xenon. Alternatively, a CRT of 160 ps can be obtained instrumenting the scanner with (much cheaper) blue-sensitive SiPMs coated with a suitable wavelength shifter. These results show the excellent time of flight capabilities of a PET device based in liquid xenon.  
  Address [Gomez-Cadenas, J. J.; Benlloch-Rodriguez, J. M.; Ferrario, P.; Rodriguez, J.] CSIC, Inst Fis Corpuscular IFIC, Calle Catedrat Jose Beltran 2, Valencia 46980, Spain, Email: paola.ferrario@ific.uv.es  
  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:000387862300011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2866  
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Author Barenboim, G.; Chen, J.Z.; Hannestad, S.; Oldengott, I.M.; Tram, T.; Wong, Y.Y.Y. url  doi
openurl 
  Title (up) Invisible neutrino decay in precision cosmology Type Journal Article
  Year 2021 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 03 Issue 3 Pages 087 - 53pp  
  Keywords cosmological neutrinos; neutrino properties; CMBR theory; cosmological parameters from CMBR  
  Abstract We revisit the topic of invisible neutrino decay in the precision cosmological context, via a first-principles approach to understanding the cosmic microwave background and large-scale structure phenomenology of such a non-standard physics scenario. Assuming an effective Lagrangian in which a heavier standard-model neutrino nu(H) couples to a lighter one nu(l) and a massless scalar particle phi via a Yukawa interaction, we derive from first principles the complete set of Boltzmann equations, at both the spatially homogeneous and the firstorder inhomogeneous levels, for the phase space densities of nu(H), nu(l), and phi in the presence of the relevant decay and inverse decay processes. With this set of equations in hand, we perform a critical survey of recent works on cosmological invisible neutrino decay in both limits of decay while nu(H) is ultra-relativistic and non-relativistic. Our two main findings are: (i) in the non-relativistic limit, the effective equations of motion used to describe perturbations in the neutrino-scalar system in the existing literature formally violate momentum conservation and gauge invariance, and (ii) in the ultra-relativistic limit, exponential damping of the anisotropic stress does not occur at the commonly-used rate Gamma(T) = (1/tau(0))( m(nu H)/E-nu H)(3), but at a rate similar to (1/ tau(0))(m(nu H)/E-nu H)(5). Both results are model-independent. The impact of the former finding on the cosmology of invisible neutrino decay is likely small. The latter, however, implies a significant revision of the cosmological limit on the neutrino lifetime tau(0) from tau(old)(0) greater than or similar to 1.2 x 10(9) s (m(nu H)/50 meV)(3) to tau(0) greater than or similar to (4 x 10(5) -> 4 x 10(6)) s (m(nu H)/50 meV)(5).  
  Address [Barenboim, Gabriela; Oldengott, Isabel M.] Univ Valencia, Dept Fis Teor, CSIC, Burjassot 46100, Spain, Email: gabriela.barenboim@uv.es;  
  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:000636717400082 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4782  
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Author Stadler, J.; Boehm, C.; Mena, O. url  doi
openurl 
  Title (up) Is it mixed dark matter or neutrino masses? Type Journal Article
  Year 2020 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 01 Issue 1 Pages 039 - 18pp  
  Keywords cluster counts; cosmological parameters from CMBR; cosmological parameters from LSS; neutrino masses from cosmology  
  Abstract In this paper, we explore a scenario where the dark matter is a mixture of interacting and non interacting species. Assuming dark matter-photon interactions for the interacting species, we find that the suppression of the matter power spectrum in this scenario can mimic that expected in the case of massive neutrinos. Our numerical studies include present limits from Planck Cosmic Microwave Background data, which render the strength of the dark matter photon interaction unconstrained when the fraction of interacting dark matter is small. Despite the large entangling between mixed dark matter and neutrino masses, we show that future measurements from the Dark Energy Instrument (DESI) could help in establishing the dark matter and the neutrino properties simultaneously, provided that the interaction rate is very close to its current limits and the fraction of interacting dark matter is at least of O (10%). However, for that region of parameter space where a small fraction of interacting DM coincides with a comparatively large interaction rate, our analysis highlights a considerable degeneracy between the mixed dark matter parameters and the neutrino mass scale.  
  Address [Stadler, Julia; Boehm, Celine] Univ Durham, Inst Particle Phys Phenomenol, South Rd, Durham DH1 3LE, England, Email: jstadler@mpe.mpg.de;  
  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:000528025800040 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4383  
Permanent link to this record
 

 
Author Giare, W.; Renzi, F.; Mena, O.; Di Valentino, E.; Melchiorri, A. url  doi
openurl 
  Title (up) Is the Harrison-Zel'dovich spectrum coming back? ACT preference for n(s) similar to 1 and its discordance with Planck Type Journal Article
  Year 2023 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 521 Issue 2 Pages 2911-2918  
  Keywords cosmological parameters; inflation; cosmology: observations; cosmology: theory  
  Abstract The Data Release 4 of the Atacama Cosmology Telescope (ACT) shows an agreement with an Harrison-Zel'dovich primordial spectrum (n(s) = 1.009 +/- 0.015), introducing a tension with a significance of 99.3 per cent Confidence Level (CL) with the results from the Planck satellite. The discrepancy on the value of the scalar spectral index is neither alleviated with the addition of large scale structure information nor with the low multipole polarization data. We discuss possible avenues to alleviate the tension relying on either neglecting polarization measurements from ACT or in extending different sectors of the theory.  
  Address [Giare, William] Ctr Nazl INFN Studi Avanzati, Galileo Galileo Inst Theoret Phys, Largo Enr Fermi 2, I-50125 Florence, Italy, Email: william.giare@gmail.com  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000957248500013 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5510  
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