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Author Reid, B.A.; Verde, L.; Jimenez, R.; Mena, O.
Title Robust neutrino constraints by combining low redshift observations with the CMB Type Journal Article
Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 01 Issue 1 Pages 003 - 21pp
Keywords cluster counts; cosmological parameters from LSS; neutrino masses from cosmology; cosmological parameters from CMBR
Abstract We illustrate how recently improved low-redshift cosmological measurements can tighten constraints on neutrino properties. In particular we examine the impact of the assumed cosmological model on the constraints. We first consider the new HST H-0 = 74.2 +/- 3.6 measurement by Riess et al. (2009) and the sigma(8)(Omega(m)/0.25)(0.41) = 0.832 +/- 0.033 constraint from Rozo et al. (2009) derived from the SDSS maxBCG Cluster Catalog. In a ACDM model and when combined with WMAP5 constraints, these low-redshift measurements constrain Sigma m(v) < 0.4 eV at the 95% confidence level. This bound does not relax when allowing for the running of the spectral index or for primordial tensor perturbations. When adding also Supernovae and BAO constraints, we obtain a 95% upper limit of Sigma m(v) < 0.3eV. We test the sensitivity of the neutrino mass constraint to the assumed expansion history by both allowing a dark energy equation of state parameter w not equal -1 and by studying a model with coupling between dark energy and dark matter, which allows for variation in w, Omega(k), and dark coupling strength xi. When combining CMB, H-0 and the SDSS LRG halo power spectrum from Reid et al. 2009, we find that in this very general model, Sigma m(v) < 0.51 eV with 95% confidence. If we allow the number of relativistic species N-rel to vary in a ACDM model with Sigma m(v) = 0, we find N-rel = 3.76(-0.68)(+0.63)(+1.38 -1.21) for the 68% and 95% confidence intervals. We also report prior-independent constraints, which are in excellent agreement with the Bayesian constraints.
Address [Reid, Beth A.] Univ Barcelona, Inst Sci Cosmos ICC, E-08028 Barcelona, Spain, Email: beth.ann.reid@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 1475-7516 ISBN Medium
Area Expedition Conference
Notes ISI:000273314600008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 511
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Author Oliveira, C.A.B.; Sorel, M.; Martin-Albo, J.; Gomez-Cadenas, J.J.; Ferreira, A.L.; Veloso, J.F.C.A.
Title Energy resolution studies for NEXT Type Journal Article
Year 2011 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 6 Issue Pages P05007 - 13pp
Keywords Scintillators, scintillation and light emission processes (solid, gas and liquid scintillators); Detector modelling and simulations II (electric fields, charge transport, multiplication and induction, pulse formation, electron emission etc); Large detector systems for particle and astroparticle physics; Time projection chambers
Abstract This work aims to present the current state of simulations of electroluminescence (EL) produced in gas-based detectors with special interest for NEXT – Neutrino Experiment with a Xenon TPC. NEXT is a neutrinoless double beta decay experiment, thus needs outstanding energy resolution which can be achieved by using electroluminescence. The process of light production is reviewed and properties such as EL yield and associated fluctuations, excitation and electroluminescence efficiencies, and energy resolution, are calculated. An EL production region with a 5 mm width gap between two infinite parallel planes is considered, where a uniform electric field is produced. The pressure and temperature considered are 10 bar and 293 K, respectively. The results show that, even for low values of VUV photon detection efficiency, good energy resolution can be achieved: below 0.4% (FWHM) at Q(beta beta) = 2.458 MeV.
Address [Oliveira, CAB; Ferreira, AL; Veloso, JFCA] Univ Aveiro, Dept Phys, i3N, P-3810193 Aveiro, Portugal, Email: carlos.oliveira@ua.pt
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:000294491900008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 747
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Author Yepes, H.
Title The ANTARES neutrino detector instrumentation Type Journal Article
Year 2012 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 7 Issue Pages C01022 - 9pp
Keywords Large detector-systems performance; Performance of High Energy Physics Detectors; Detector alignment and calibration methods (lasers, sources, particle-beams)
Abstract ANTARES is actually the fully operational and the largest neutrino telescope in the Northern hemisphere. Located in the Mediterranean Sea, it consists of a 3D array of 885 photomultiplier tubes (PMTs) arranged in 12 detection lines (25 storeys each), able to detect the Cherenkov light induced by upgoing relativistic muons produced in the interaction of high energy cosmic neutrinos with the detector surroundings. Among its physics goals, the search for neutrino astrophysical sources and the indirect detection of dark matter particles coming from the sun are of particular interest. To reach these goals, good accuracy in track reconstruction is mandatory, so several calibration systems for timing and positioning have been developed. In this contribution we will present the design of the detector, calibration systems, associated equipment and its performance on track reconstruction.
Address Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: Harold.Yepes@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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000303806200022 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1041
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Author NEXT Collaboration (Alvarez, V. et al); Carcel, S.; Cervera-Villanueva, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J.J.; Gonzalez, K.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Muñoz Vidal, J.; Nebot-Guinot, M.; Rodriguez, J.; Serra, L.; Sorel, M.; Yahlali, N.
Title NEXT-100 Technical Design Report (TDR). Executive summary Type Journal Article
Year 2012 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 7 Issue Pages T06001 - 34pp
Keywords Detector design and construction technologies and materials; Time projection chambers
Abstract In this Technical Design Report (TDR) we describe the NEXT-100 detector that will search for neutrinoless double beta decay (beta beta 0v) in Xe-136 at the Laboratorio Subterraneo de Canfranc (LSC), in Spain. The document formalizes the design presented in our Conceptual Design Report (CDR): an electroluminescence time projection chamber, with separate readout planes for calorimetry and tracking, located, respectively, behind cathode and anode. The detector is designed to hold a maximum of about 150 kg of xenon at 15 bar, or 100 kg at 10 bar. This option builds in the capability to increase the total isotope mass by 50% while keeping the operating pressure at a manageable level. The readout plane performing the energy measurement is composed of Hamamatsu R11410-10 photomultipliers, specially designed for operation in low-background, xenon-based detectors. Each individual PMT will be isolated from the gas by an individual, pressure resistant enclosure and will be coupled to the sensitive volume through a sapphire window. The tracking plane consists in an array of Hamamatsu S10362-11-050P MPPCs used as tracking pixels. They will be arranged in square boards holding 64 sensors (8 x 8) with a 1-cm pitch. The inner walls of the TPC, the sapphire windows and the boards holding the MPPCs will be coated with tetraphenyl butadiene (TPB), a wavelength shifter, to improve the light collection.
Address [Alvarez, V.; Carcel, S.; Cervera, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J. J.; Gonzalez, K.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Munoz Vidal, J.; Nebot, M.; Rodriguez, J.; Serra, L.; Sorel, M.; Yahlali, N.] CSIC, Inst Fis Corpuscular IFIC, Valencia 46980, Spain, Email: gomez@mail.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:000306072000030 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1097
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Author Semikoz, V.B.; Sokoloff, D.D.; Valle, J.W.F.
Title Lepton asymmetries and primordial hypermagnetic helicity evolution Type Journal Article
Year 2012 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 06 Issue 6 Pages 008 - 12pp
Keywords Magnetohydrodynamics; galactic magnetic fields; cosmic magnetic fields theory; particle physics – cosmology connection
Abstract The hypermagnetic helicity density at the electroweak phase transition (EWPT) exceeds many orders of magnitude the galactic magnetic helicity density. Together with previous magnetic helicity evolution calculations after the EWPT and hypermagnetic helicity conversion to the magnetic one at the EWPT, the present calculation completes the description of the evolution of this important topological feature of cosmological magnetic fields. It suggests that if the magnetic field seeding the galactic dynamo has a primordial origin, it should be substantially helical. This should be taken into account in scenarios of galactic magnetic field evolution with a cosmological seed.
Address [Semikoz, V. B.; Valle, J. W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: semikoz@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:000306003500008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1101
Permanent link to this record