|   | 
Details
   web
Records
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 (up) 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 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
Permanent link to this record
 

 
Author LAGUNA-LBNO Collaboration (Agarwalla, S.K., et al); Cervera-Villanueva, A.; Gomez-Cadenas, J.J.; Sorel, M.
Title The mass-hierarchy and CP-violation discovery reach of the LBNO long-baseline neutrino experiment Type Journal Article
Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 094 - 38pp
Keywords (up) Oscillation; Neutrino Detectors and Telescopes; CP violation
Abstract The next generation neutrino observatory proposed by the LBNO collaboration will address fundamental questions in particle and astroparticle physics. The experiment consists of a far detector, in its first stage a 20 kt LAr double phase TPC and a magnetised iron calorimeter, situated at 2300 km from CERN and a near detector based on a highpressure argon gas TPC. The long baseline provides a unique opportunity to study neutrino flavour oscillations over their 1st and 2nd oscillation maxima exploring the L/E behaviour, and distinguishing effects arising from delta(CP) and matter. In this paper we have reevaluated the physics potential of this setup for determining the mass hierarchy (MH) and discovering CP-violation (CPV), using a conventional neutrino beam from the CERN SPS with a power of 750 kW. We use conservative assumptions on the knowledge of oscillation parameter priors and systematic uncertainties. The impact of each systematic error and the precision of oscillation prior is shown. We demonstrate that the first stage of LBNO can determine unambiguously the MH to > 5 sigma C.L. over the whole phase space. We show that the statistical treatment of the experiment is of very high importance, resulting in the conclusion that LBNO has similar to 100% probability to determine the MH in at most 4-5 years of running. Since the knowledge of MH is indispensable to extract delta(CP) from the data, the first LBNO phase can convincingly give evidence for CPV on the 3 sigma C.L. using today's knowledge on oscillation parameters and realistic assumptions on the systematic uncertainties.
Address [Banerjee, D.; Bay, F.; Cantini, C.; Crivelli, P.; Di Luise, S.; Epprecht, L.; Gendotti, A.; Horikawa, S.; Murphy, S.; Nguyen, K.; Nikolics, K.; Periale, L.; Resnati, F.; Rubbia, A.; Sergiampietri, F.; Sgalaberna, D.; Viant, T.; Wu, S.] Swiss Fed Inst Technol, Inst Particle Phys, Zurich, Switzerland, Email: andre.rubbia@cern.ch
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 Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000337086700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1821
Permanent link to this record
 

 
Author Super-Kamiokande Collaboration (Abe, K. et al); Molina Sedgwick, S.
Title Neutron tagging following atmospheric neutrino events in a water Cherenkov detector Type Journal Article
Year 2022 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 17 Issue 10 Pages P10029 - 41pp
Keywords (up) Particle identification methods; Cherenkov detectors; Neutrino detectors; Large detector systems for particle and astroparticle physics
Abstract We present the development of neutron-tagging techniques in Super-Kamiokande IV using a neural network analysis. The detection efficiency of neutron capture on hydrogen is estimated to be 26%, with a mis-tag rate of 0.016 per neutrino event. The uncertainty of the tagging efficiency is estimated to be 9.0%. Measurement of the tagging efficiency with data from an Americium-Beryllium calibration agrees with this value within 10%. The tagging procedure was performed on 3,244.4 days of SK-IV atmospheric neutrino data, identifying 18,091 neutrons in 26,473 neutrino events. The fitted neutron capture lifetime was measured as 218 +/- 9 μs.
Address [Abe, K.; Haga, Y.; Hayato, Y.; Hiraide, K.; Ieki, K.; Ikeda, M.; Imaizumi, S.; Iyogi, K.; Kameda, J.; Kanemura, Y.; Kataoka, Y.; Kato, Y.; Kishimoto, Y.; Miki, S.; Mine, S.; Miura, M.; Mochizuki, T.; Moriyama, S.; Nagao, Y.; Nakahata, M.; Nakajima, T.; Nakano, Y.; Nakayama, S.; Okada, T.; Okamoto, K.; Orii, A.; Sato, K.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Suzuki, Y.; Takeda, A.; Takemoto, Y.; Takenaka, A.; Tanaka, H.; Tasaka, S.; Tomura, T.; Ueno, K.; Watanabe, S.; Yano, T.; Yokozawa, T.] Univ Tokyo, Inst Cosm Ray Res, Kamioka Observ, Gifu, Akita 5061205, Japan, Email: hayato@icrr.u-tokyo.ac.jp
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:000898723700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5441
Permanent link to this record