Abstract
A θ13 oscillation analysis based on the observed antineutrino rates at the Double Chooz far and near detectors for different reactor power conditions is presented. This approach provides a so far unique simultaneous determination of θ13 and the total background rates without relying on any assumptions on the specific background contributions. The analysis comprises 865 days of data collected in both detectors with at least one reactor in operation. The oscillation results are enhanced by the use of 24.06 days (12.74 days) of reactor-off data in the far (near) detector. The analysis considers the \( {\overline{\nu}}_e \) interactions up to a visible energy of 8.5 MeV, using the events at higher energies to build a cosmogenic background model considering fast-neutrons interactions and 9Li decays. The background-model-independent determination of the mixing angle yields sin2(2θ13) = 0.094 ± 0.017, being the best-fit total background rates fully consistent with the cosmogenic background model. A second oscillation analysis is also performed constraining the total background rates to the cosmogenic background estimates. While the central value is not significantly modified due to the consistency between the reactor-off data and the background estimates, the addition of the background model reduces the uncertainty on θ13 to 0.015. Along with the oscillation results, the normalization of the anti-neutrino rate is measured with a precision of 0.86%, reducing the 1.43% uncertainty associated to the expectation.
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References
Particle Data Group collaboration, Review of Particle Physics, Phys. Rev. D 98 (2018) 030001 [INSPIRE].
SNO collaboration, Direct evidence for neutrino flavor transformation from neutral current interactions in the Sudbury Neutrino Observatory, Phys. Rev. Lett. 89 (2002) 011301 [nucl-ex/0204008] [INSPIRE].
KamLAND collaboration, First results from KamLAND: Evidence for reactor anti-neutrino disappearance, Phys. Rev. Lett. 90 (2003) 021802 [hep-ex/0212021] [INSPIRE].
Super-Kamiokande collaboration, Evidence for an oscillatory signature in atmospheric neutrino oscillation, Phys. Rev. Lett. 93 (2004) 101801 [hep-ex/0404034] [INSPIRE].
K2K collaboration, Evidence for muon neutrino oscillation in an accelerator-based experiment, Phys. Rev. Lett. 94 (2005) 081802 [hep-ex/0411038] [INSPIRE].
Double CHOOZ collaboration, Improved measurements of the neutrino mixing angle θ13 with the Double CHOOZ detector, JHEP 10 (2014) 086 [Erratum ibid. 02 (2015) 074] [arXiv:1406.7763] [INSPIRE].
Daya Bay collaboration, Measurement of the Electron Antineutrino Oscillation with 1958 Days of Operation at Daya Bay, Phys. Rev. Lett. 121 (2018) 241805 [arXiv:1809.02261] [INSPIRE].
RENO collaboration, Spectral Measurement of the Electron Antineutrino Oscillation Amplitude and Frequency using 500 Live Days of RENO Data, Phys. Rev. D 98 (2018) 012002 [arXiv:1610.04326] [INSPIRE].
Double CHOOZ collaboration, Double CHOOZ θ13 measurement via total neutron capture detection, Nature Phys. 16 (2020) 558 [arXiv:1901.09445] [INSPIRE].
T2K collaboration, Constraint on the matter-antimatter symmetry-violating phase in neutrino oscillations, Nature 580 (2020) 339 [Erratum ibid. 583 (2020) E16] [arXiv:1910.03887] [INSPIRE].
Double CHOOZ collaboration, Background-independent measurement of θ13 in Double CHOOZ, Phys. Lett. B 735 (2014) 51 [arXiv:1401.5981] [INSPIRE].
Y. Declais et al., Study of reactor anti-neutrino interaction with proton at Bugey nuclear power plant, Phys. Lett. B 338 (1994) 383 [INSPIRE].
Double CHOOZ collaboration, First Measurement of θ13 from Delayed Neutron Capture on Hydrogen in the Double CHOOZ Experiment, Phys. Lett. B 723 (2013) 66 [arXiv:1301.2948] [INSPIRE].
Double CHOOZ collaboration, Measurement of θ13 in Double CHOOZ using neutron captures on hydrogen with novel background rejection techniques, JHEP 01 (2016) 163 [arXiv:1510.08937] [INSPIRE].
Double CHOOZ collaboration, Yields and production rates of cosmogenic 9Li and 8He measured with the Double CHOOZ near and far detectors, JHEP 11 (2018) 053 [arXiv:1802.08048] [INSPIRE].
Double CHOOZ collaboration, Characterization of the Spontaneous Light Emission of the PMTs used in the Double CHOOZ Experiment, 2016 JINST 11 P08001 [arXiv:1604.06895] [INSPIRE].
P. Huber, On the determination of anti-neutrino spectra from nuclear reactors, Phys. Rev. C 84 (2011) 024617 [Erratum ibid. 85 (2012) 029901] [arXiv:1106.0687] [INSPIRE].
T.A. Mueller et al., Improved Predictions of Reactor Antineutrino Spectra, Phys. Rev. C 83 (2011) 054615 [arXiv:1101.2663] [INSPIRE].
K. Schreckenbach, G. Colvin, W. Gelletly and F. Von Feilitzsch, DEtermination of the anti-neutrino spectrum from 235U thermal neutron fission products up to 9.5 MeV, Phys. Lett. B 160 (1985) 325 [INSPIRE].
N. Haag et al., Experimental Determination of the Antineutrino Spectrum of the Fission Products of 238U, Phys. Rev. Lett. 112 (2014) 122501 [arXiv:1312.5601] [INSPIRE].
Double CHOOZ collaboration, Direct Measurement of Backgrounds using Reactor-Off Data in Double CHOOZ, Phys. Rev. D 87 (2013) 011102 [arXiv:1210.3748] [INSPIRE].
R.A. Forrest et al., FISPACT-2007: user manual, UKAEA-FUS-534 (2007) [http://www.ccfe.ac.uk].
P. Novella, The antineutrino energy structure in reactor experiments, Adv. High Energy Phys. 2015 (2015) 364392 [arXiv:1512.03366] [INSPIRE].
S. Parke, What is \( \Delta {m}_{ee}^2 \)?, Phys. Rev. D 93 (2016) 053008 [arXiv:1601.07464] [INSPIRE].
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ArXiv ePrint: 2007.13431
Deceased (H. de Kerret)
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The Double Chooz collaboration., Abrahão, T., Almazan, H. et al. Reactor rate modulation oscillation analysis with two detectors in Double Chooz. J. High Energ. Phys. 2021, 190 (2021). https://doi.org/10.1007/JHEP01(2021)190
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DOI: https://doi.org/10.1007/JHEP01(2021)190