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Author Gomez-Cadenas, J.J.; Martin-Albo, J.; Sorel, M.; Ferrario, P.; Monrabal, F.; Muñoz, J.; Novella, P.; Poves, A.
Title Sense and sensitivity of double beta decay experiments Type Journal Article
Year 2011 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 06 Issue 6 Pages 007 - 30pp
Keywords double beta decay; neutrino experiments; neutrino properties
Abstract The search for neutrinoless double beta decay is a very active field in which the number of proposals for next-generation experiments has proliferated. In this paper we attempt to address both the sense and the sensitivity of such proposals. Sensitivity comes first, by means of proposing a simple and unambiguous statistical recipe to derive the sensitivity to a putative Majorana neutrino mass, m(beta beta). In order to make sense of how the different experimental approaches compare, we apply this recipe to a selection of proposals, comparing the resulting sensitivities. We also propose a “physics-motivated range” (PMR) of the nuclear matrix elements as a unifying criterium between the different nuclear models. The expected performance of the proposals is parametrized in terms of only four numbers: energy resolution, background rate (per unit time, isotope mass and energy), detection efficiency, and beta beta isotope mass. For each proposal, both a reference and an optimistic scenario for the experimental performance are studied. In the reference scenario we find that all the proposals will be able to partially explore the degenerate spectrum, without fully covering it, although four of them (KamLAND-Zen, CUORE, NEXT and EXO) will approach the 50 meV boundary. In the optimistic scenario, we find that CUORE and the xenon-based proposals (KamLAND-Zen, EXO and NEXT) will explore a significant fraction of the inverse hierarchy, with NEXT covering it almost fully. For the long term future, we argue that Xe-136-based experiments may provide the best case for a 1-ton scale experiment, given the potentially very low backgrounds achievable and the expected scalability to large isotope masses.
Address [Gomez-Cadenas, J. J.; Martin-Albo, J.; Sorel, M.; Ferrario, P.; Monrabal, F.; Munoz, J.] CSIC, IFIC, Valencia 46071, 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 (up) Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes ISI:000292332400007 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 675
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Author Novella, P.
Title The antineutrino energy structure in reactor experiments Type Journal Article
Year 2015 Publication Advances in High Energy Physics Abbreviated Journal Adv. High. Energy Phys.
Volume 2015 Issue Pages 364392 - 12pp
Keywords
Abstract The recent observation of an energy structure in the reactor antineutrino spectrum is reviewed. The reactor experiments Daya Bay, Double Chooz, and RENO have reported a consistent excess of antineutrinos deviating from the flux predictions, with a local significance of about 4 sigma between 4 and 6 MeV of the positron energy spectrum. The possible causes of the structure are analyzed in this work, along with the different experimental approaches developed to identify its origin. Considering the available data and results from the three experiments, the most likely explanation concerns the reactor flux predictions and the associated uncertainties. Therefore, the different current models are described and compared. The possible sources of incompleteness or inaccuracy of such models are discussed, as well as the experimental data required to improve their precision.
Address [Novella, Pau] CSIC, Inst Fis Corpuscular IFIC, Paterna 46980, Spain, Email: pau.novella@ific.uv.es
Corporate Author Thesis
Publisher Hindawi Publishing Corp Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue (up) Edition
ISSN 1687-7357 ISBN Medium
Area Expedition Conference
Notes WOS:000367926000001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2531
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Author Double Chooz collaboration (Abe, Y. et al); Novella, P.
Title Measurement of theta(13) in Double Chooz using neutron captures on hydrogen with novel background rejection techniques Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 163 - 29pp
Keywords Oscillation; Electroweak interaction; Neutrino Detectors and Telescopes; Flavor physics
Abstract The Double Chooz collaboration presents a measurement of the neutrino mixing angle theta(13) using reactor (nu) over bar (e) observed via the inverse beta decay reaction in which the neutron is captured on hydrogen. This measurement is based on 462.72 live days data, approximately twice as much data as in the previous such analysis, collected with a detector positioned at an average distance of 1050m from two reactor cores. Several novel techniques have been developed to achieve significant reductions of the backgrounds and systematic uncertainties. Accidental coincidences, the dominant background in this analysis, are suppressed by more than an order of magnitude with respect to our previous publication by a multi-variate analysis. These improvements demonstrate the capability of precise measurement of reactor (nu) over bar (e) without gadolinium loading. Spectral distortions from the (nu) over bar (e) reactor flux predictions previously reported with the neutron capture on gadolinium events are confirmed in the independent data sample presented here. A value of sin(2) 2 theta(13) = 0.095(0.039)(+0.039)(stat+syst) is obtained from a fit to the observed event rate as a function of the reactor power, a method insensitive to the energy spectrum shape. A simultaneous fit of the hydrogen capture events and of the gadolinium capture events yields a measurement of sin(2) 2 theta(13) = 0.088 +/- 0.033(stat+syst).
Address [Felde, J.] Univ Maryland, Dept Phys, College Pk, MD 20742 USA, Email: amil@nevis.columbia.edu;
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 (up) Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000369294300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2543
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Author NEXT Collaboration (Ferrario, P. et al); Laing, A.; Lopez-March, N.; Gomez-Cadenas, J.J.; Alvarez, V.; Carcel, S.; Cervera-Villanueva, A.; Diaz, J.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Monserrate, M.; Muñoz Vidal, J.; Nebot-Guinot, M.; Novella, P.; Querol, M.; Renner, J.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Yahlali, N.
Title First proof of topological signature in the high pressure xenon gas TPC with electroluminescence amplification for the NEXT experiment Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 104 - 18pp
Keywords Dark Matter; Double Beta Decay
Abstract The NEXT experiment aims to observe the neutrinoless double beta decay of Xe-136 in a high-pressure xenon gas TPC using electroluminescence (EL) to amplify the signal from ionization. One of the main advantages of this technology is the possibility to reconstruct the topology of events with energies close to Q(beta beta). This paper presents the first demonstration that the topology provides extra handles to reject background events using data obtained with the NEXT-DEMO prototype. Single electrons resulting from the interactions of Na-22 1275 keV gammas and electron-positron pairs produced by conversions of gammas from the Th-228 decay chain were used to represent the background and the signal in a double beta decay. These data were used to develop algorithms for the reconstruction of tracks and the identification of the energy deposited at the end-points, providing an extra background rejection factor of 24.3 +/- 1.4 (stat.)%, while maintaining an efficiency of 66.7 +/- 1.% for signal events.
Address [Ferrario, P.; Laing, A.; Lopez-March, N.; Gomez-Cadenas, J. J.; Alvarez, V.; Carcel, S.; Cervera, A.; Diaz, J.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Martinez, A.; Monrabal, F.; Monserrate, M.; Munoz Vidal, J.; Nebot-Guinot, M.; Novella, P.; Querol, M.; Renner, J.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Yahlali, N.] CSIC, Inst Fis Corpuscular IFIC, Jose Beltran 2, Valencia 46980, Spain, Email: paola.ferrario@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 (up) Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000370438900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2560
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Author Double Chooz collaboration (Abe, Y. et al); Novella, P.
Title Muon capture on light isotopes measured with the Double Chooz detector Type Journal Article
Year 2016 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 93 Issue 5 Pages 054608 - 18pp
Keywords
Abstract Using the Double Chooz detector, designed to measure the neutrino mixing angle theta(13), the products of mu(-) capture on C-12, C-13, N-14, and O-16 have been measured. Over a period of 489.5 days, 2.3 x 10(6) stopping cosmic mu(-) have been collected, of which 1.8 x 10(5) captured on carbon, nitrogen, or oxygen nuclei in the inner detector scintillator or acrylic vessels. The resulting isotopes were tagged using prompt neutron emission (when applicable), the subsequent beta decays, and, in some cases, beta-delayed neutrons. The most precise measurement of the rate of C-12(mu(-), nu)B-12 to date is reported: 6.57(-0.21)(+0.11) x 10(3) s(-1), or (17.35(-0.59)(+0.35))% of nuclear captures. By tagging excited states emitting gamma s, the ground state transition rate to B-12 has been determined to be 5.68(-0.23)(+0.14) x 10(3) s(-1). The heretofore unobserved reactions C-12(mu(-), nu alpha)Li-8, C-13(mu(-), nu n alpha)Li-8, and C-13(mu(-), nu n)B-12 are measured. Further, a population of beta n decays following stopping muons is identified with 5.5 sigma significance. Statistics limit our ability to identify these decays definitively. Assuming negligible production of He-8, the reaction C-13(mu(-), nu alpha)Li-9 is found to be present at the 2.7 sigma level. Limits are set on a variety of other processes.
Address [Alt, C.; Bekman, I.; Cabrera, A.; Hellwig, D.; Lucht, S.; Schoppmann, S.; Soiron, M.; Stahl, A.; Wiebusch, C.] Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany, Email: strait@hep.uchicago.edu
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 (up) Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000375999500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2679
Permanent link to this record