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Author NEMO-3 Collaboration (Argyriades, J. et al); Diaz, J.; Martin-Albo, J.; Monrabal, F.; Novella, P.; Serra, L.; Yahlali, N. url  doi
openurl 
  Title Spectral modeling of scintillator for the NEMO-3 and SuperNEMO detectors Type Journal Article
  Year 2011 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 625 Issue 1 Pages 20-28  
  Keywords Scintillation; Photomultiplier; Plastic scintillators; Optical photon transport; GEANT 4; Double beta decay  
  Abstract We have constructed a GEANT4-based detailed software model of photon transport in plastic sontillator blocks and have used it to study the NEMO-3 and SuperNEMO calorimeters employed in experiments designed to search for neutnnoless double beta decay We compare our simulations to measurements using conversion electrons from a calibration source of (BI)-B-207 and show that the agreement is improved if wavelength-dependent properties of the calorimeter are taken into account In this article we briefly describe our modeling approach and results of our studies.  
  Address [Lang, K.; Pahlka, R. B.] Univ Texas Austin, Dept Phys, Austin, TX 78712 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 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000285432400004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 587  
Permanent link to this record
 

 
Author Gomez-Cadenas, J.J.; Martin-Albo, J.; Mezzetto, M.; Monrabal, F.; Sorel, M. url  doi
openurl 
  Title The search for neutrinoless double beta decay Type Journal Article
  Year 2012 Publication Rivista del Nuovo Cimento Abbreviated Journal Riv. Nuovo Cimento  
  Volume 35 Issue 2 Pages 29-98  
  Keywords  
  Abstract In the last two decades the search for neutrinoless double beta decay has evolved into one of the highest priorities for understanding neutrinos and the origin of mass. The main reason for this paradigm shift has been the discovery of neutrino oscillations, which clearly established the existence of massive neutrinos. An additional motivation for conducting such searches comes from the existence of an unconfirmed, but not refuted, claim of evidence for neutrinoless double decay in Ge-76. As a consequence, a new generation of experiments, employing different detection techniques and beta beta isotopes, is being actively promoted by experimental groups across the world. In addition, nuclear theorists are making remarkable progress in the calculation of the neutrinoless double beta. decay nuclear matrix elements, thus eliminating a substantial part of the theoretical uncertainties affecting the particle physics interpretation of this process. In this report, we review the main aspects of the double beta decay process and some of the most relevant experiments. The picture that emerges is one where searching for neutrinoless double beta decay is recognized to have both far-reaching theoretical implications and promising prospects for experimental observation in the near future.  
  Address [Gomez-Cadenas, J. J.; Martin-Albo, J.; Monrabal, F.; Sorel, M.] CSIC, Inst Fis Corpuscular IFIC, Valencia, Spain, Email: sorel@ific.uv.es  
  Corporate Author Thesis  
  Publisher Soc Italiana Fisica Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0393-697x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000301469900001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 942  
Permanent link to this record
 

 
Author Gomez-Cadenas, J.J.; Guinea, F.; Fogler, M.M.; Katsnelson, M.I.; Martin-Albo, J.; Monrabal, F.; Muñoz Vidal, J. url  doi
openurl 
  Title GraXe, graphene and xenon for neutrinoless double beta decay searches Type Journal Article
  Year 2012 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 02 Issue 2 Pages 037 - 17pp  
  Keywords neutrino experiments; double beta decay  
  Abstract We propose a new detector concept, GraXe (to be pronounced as grace), to search for neutrinoless double beta decay in Xe-136. GraXe combines a popular detection medium in rare-event searches, liquid xenon, with a new, background-free material, grapheme. In our baseline design of GraXe, a sphere made of graphene-coated titanium mesh and filled with liquid xenon (LXe) enriched in the Xe-136 isotope is immersed in a large volume of natural LXe instrumented with photodetectors. Liquid xenon is an excellent scintillator, reasonably transparent to its own light. Graphene is transparent over a large frequency range, and impermeable to the xenon. Event position could be deduced from the light pattern detected in the photosensors. External backgrounds would be shielded by the buffer of natural LXe, leaving the ultra-radiopure internal volume virtually free of background. Industrial graphene can be manufactured at a competitive cost to produce the sphere. Enriching xenon in the isotope Xe-136 is easy and relatively cheap, and there is already near one ton of enriched xenon available in the world (currently being used by the EXO, KamLAND-Zen and NEXT experiments). All the cryogenic know-how is readily available from the numerous experiments using liquid xenon. An experiment using the GraXe concept appears realistic and affordable in a short time scale, and its physics potential is enormous.  
  Address [Gomez-Cadenas, J. J.; Martin-Albo, J.; Monrabal, F.; Munoz Vidal, J.] CSIC, Inst Fis Corpuscular, IFIC, Valencia 46980, Spain, Email: gomez@mail.cern.ch;  
  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:000301176000038 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 987  
Permanent link to this record
 

 
Author NEXT Collaboration (Alvarez, V. et al); Agramunt, J.; Ball, M.; Bayarri, J.; Carcel, S.; Cervera-Villanueva, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J.J.; Gonzalez, K.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Monrabal, F.; Muñoz Vidal, J.; Nebot-Guinot, M.; Perez, J.; Rodriguez, J.; Serra, L.; Sorel, M.; Yahlali, N. url  doi
openurl 
  Title SiPMs coated with TPB: coating protocol and characterization for NEXT Type Journal Article
  Year 2012 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 7 Issue Pages P02010  
  Keywords  
  Abstract Silicon photomultipliers (SiPM) are the photon detectors chosen for the tracking read-out in NEXT, a neutrinoless beta beta decay experiment which uses a high pressure gaseous xenon time projection chamber (TPC). The reconstruction of event track and topology in this gaseous detector is a key handle for background rejection. Among the commercially available sensors that can be used for tracking, SiPMs offer important advantages, mainly high gain, ruggedness, cost-effectiveness and radio-purity. Their main drawback, however, is their non sensitivity in the emission spectrum of the xenon scintillation (peak at 175 nm). This is overcome by coating these sensors with the organic wavelength shifter tetraphenyl butadiene (TPB). In this paper we describe the protocol developed for coating the SiPMs with TPB and the measurements performed for characterizing the coatings as well as the performance of the coated sensors in the UV-VUV range.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language 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:000303940900076 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 1028  
Permanent link to this record
 

 
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. url  doi
openurl 
  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 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 (down) IFIC @ pastor @ Serial 1097  
Permanent link to this record
 

 
Author Bayes, R.; Laing, A.; Soler, F.J.P.; Cervera-Villanueva, A.; Gomez-Cadenas, J.J.; Hernandez, P.; Martin-Albo, J.; Burguet-Castell, J. url  doi
openurl 
  Title Golden channel at a neutrino factory revisited: Improved sensitivities from a magnetized iron neutrino detector Type Journal Article
  Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 86 Issue 9 Pages 093015 - 27pp  
  Keywords  
  Abstract This paper describes the performance and sensitivity to neutrino mixing parameters of a Magnetised Iron Neutrino Detector at a Neutrino Factory with a neutrino beam created from the decay of 10 GeV muons. Specifically, it is concerned with the ability of such a detector to detect muons of the opposite sign to those stored (wrong-sign muons) while suppressing contamination of the signal from the interactions of other neutrino species in the beam. A new, more realistic simulation and analysis, which improves the efficiency of this detector at low energies, has been developed using the GENIE neutrino event generator and the GEANT4 simulation toolkit. Low-energy neutrino events down to 1 GeV were selected, while reducing backgrounds to the 10(-4) level. Signal efficiency plateaus of similar to 60% for nu(mu) and similar to 70% for (nu) over bar (mu) events were achieved starting at similar to 5 GeV. Contamination from the nu(mu) -> nu(tau) oscillation channel was studied for the first time and was found to be at the level between 1% and 4%. Full response matrices are supplied for all the signal and background channels from 1 GeV to 10 GeV. The sensitivity of an experiment involving a Magnetised Iron Neutrino Detector detector of 100 ktons at 2000 km from the Neutrino Factory is calculated for the case of sin(2)2 theta(13) similar to 10(-1). For this value of theta(13), the accuracy in the measurement of the CP-violating phase is estimated to be Delta delta(CP) similar to 3 degrees-5 degrees, depending on the value of delta(CP), the CP coverage at 5 sigma is 85% and the mass hierarchy would be determined with better than 5 sigma level for all values of delta(CP).  
  Address [Bayes, R.; Laing, A.; Soler, F. J. P.] Univ Glasgow, Sch Phys & Astron, Glasgow, Lanark, Scotland  
  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:000310868700002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 1224  
Permanent link to this record
 

 
Author Edgecock, T.R. et al; Agarwalla, S.K.; Cervera-Villanueva, A.; Donini, A.; Ghosh, T.; Gomez-Cadenas, J.J.; Hernandez, P.; Martin-Albo, J.; Mena, O. url  doi
openurl 
  Title High intensity neutrino oscillation facilities in Europe Type Journal Article
  Year 2013 Publication Physical Review Special Topics-Accelerators and Beams Abbreviated Journal Phys. Rev. Spec. Top.-Accel. Beams  
  Volume 16 Issue 2 Pages 021002 - 18pp  
  Keywords  
  Abstract The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Frejus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of mu(+) and mu(-) beams in a storage ring. The far detector in this case is a 100 kt magnetized iron neutrino detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular He-6 and Ne-18, also stored in a ring. The far detector is also the MEMPHYS detector in the Frejus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the physics reach of each facility, in particular for the measurement of CP violation in the lepton sector, and estimated the cost of construction. These have demonstrated that the best facility to build is the Neutrino Factory. However, if a powerful proton driver is constructed for another purpose or if the MEMPHYS detector is built for astroparticle physics, the Super Beam also becomes very attractive.  
  Address [Edgecock, T. R.; Caretta, O.; Davenne, T.; Densam, C.; Fitton, M.; Kelliher, D.; Loveridge, P.; Machida, S.; Prior, C.; Rogers, C.; Rooney, M.; Thomason, J.; Wilcox, D.] STFC Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England  
  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 1098-4402 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000315152000001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 1333  
Permanent link to this record
 

 
Author NEXT Collaboration (Alvarez, V. et al); Carcel, S.; Cervera-Villanueva, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J.J.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Muñoz Vidal, J.; Nebot-Guinot, M.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Yahlali, N. url  doi
openurl 
  Title Near-intrinsic energy resolution for 30-662 keV gamma rays in a high pressure xenon electroluminescent TPC Type Journal Article
  Year 2013 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 708 Issue Pages 101-114  
  Keywords Xenon; Energy resolution; High-pressure; TPC; Electroluminescence; Neutrinoless double beta decay  
  Abstract We present the design, data and results from the NEXT prototype for Double Beta and Dark Matter (NEXT-DBDM) detector, a high-pressure gaseous natural xenon electroluminescent time projection chamber (TPC) that was built at the Lawrence Berkeley National Laboratory. It is a prototype of the planned NEXT-100 Xe-136 neutrino-less double beta decay (0 nu beta beta) experiment with the main objectives of demonstrating near-intrinsic energy resolution at energies up to 662 keV and of optimizing the NEXT-100 detector design and operating parameters. Energy resolutions of similar to 1% FWHM for 662 keV gamma rays were obtained at 10 and 15 atm and similar to 5% FWHM for 30 keV fluorescence xenon X-rays. These results demonstrate that 0.5% FWHM resolutions for the 2459 keV hypothetical neutrino-less double beta decay peak are realizable. This energy resolution is a factor 7-20 better than that of the current leading 0 nu beta beta experiments using liquid xenon and thus represents a significant advancement. We present also first results from a track imaging system consisting of 64 silicon photo-multipliers recently installed in NEXT-DBDM that, along with the excellent energy resolution, demonstrates the key functionalities required for the NEXT-100 0 nu beta beta search.  
  Address [Alvarez, V.; Carcel, S.; Cervera, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J. J.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Munoz Vidal, J.; Nebot-Guinot, M.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Yahlali, N.] CSIC, Inst Fis Corpuscular IFIC, Valencia 46980, Spain, Email: agoldschmidt@lbl.gov  
  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 WOS:000316192300015 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 1369  
Permanent link to this record
 

 
Author NEXT Collaboration (Alvarez, V. et al); Carcel, S.; Cervera-Villanueva, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J.J.; Laing, A.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Muñoz Vidal, J.; Nebot-Guinot, M.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Yahlali, N. url  doi
openurl 
  Title Initial results of NEXT-DEMO, a large-scale prototype of the NEXT-100 experiment Type Journal Article
  Year 2013 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 8 Issue Pages P04002 - 25pp  
  Keywords Double-beta decay detectors; Time projection chambers; Pattern recognition, cluster finding, calibration and fitting methods  
  Abstract NEXT-DEMO is a large-scale prototype of the NEXT-100 detector, an electroluminescent time projection chamber that will search for the neutrinoless double beta decay of Xe-136 using 100-150 kg of enriched xenon gas. NEXT-DEMO was built to prove the expected performance of NEXT-100, namely, energy resolution better than 1% FWHM at 2.5MeV and event topological reconstruction. In this paper we describe the prototype and its initial results. A resolution of 1.75% FWHM at 511 keV (which extrapolates to 0.8% FWHM at 2.5 MeV) was obtained at 10 bar pressure using a gamma-ray calibration source. Also, a basic study of the event topology along the longitudinal coordinate is presented, proving that it is possible to identify the distinct dE/dx of electron tracks in high-pressure xenon using an electroluminescence TPC.  
  Address CSIC, Inst Fis Corpuscular IFIC, Valencia 46980, Spain, Email: justo.martin-albo@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:000317462400009 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 1414  
Permanent link to this record
 

 
Author Gomez-Cadenas, J.J.; Martin-Albo, J.; Muñoz Vidal, J.; Pena-Garay, C. url  doi
openurl 
  Title Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations Type Journal Article
  Year 2013 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 03 Issue 3 Pages 043 - 17pp  
  Keywords neutrino masses from cosmology; double beta decay  
  Abstract The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, with Sigma m(nu) = (0.32 +/- 0.11) eV. This result, if con firmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass m(beta beta) involved in neutrinoless double beta decay (beta beta 0 nu) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based beta beta 0 nu experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg.year, could already have a sizeable opportunity to observe beta beta 0 nu events, and their combined discovery potential is quite large. The next generation, with an exposure in the range of 10 ton.year, would have a much more enhanced sensitivity, in particular due to the very low specific background that all the xenon technologies (liquid xenon, high-pressure xenon and xenon dissolved in liquid scintillator) can achieve. In addition, a high-pressure xenon gas TPC also features superb energy resolution. We show that such detector can fully explore the range of allowed effective Majorana masses, thus making a discovery very likely.  
  Address CSIC, Inst Fis Corpuscular, IFIC, Valencia 46090, Spain, Email: gomez@mail.cern.ch;  
  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:000316989200044 Approved no  
  Is ISI yes International Collaboration no  
  Call Number (down) IFIC @ pastor @ Serial 1434  
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