Study of the wave packet treatment of neutrino oscillation at Daya Bay

Abstract

The disappearance of reactor νe observed by the Daya Bay experiment is examined in the framework of a model in which the neutrino is described by a wave packet with a relative intrinsic momentum dispersion σ rel . Three pairs of nuclear reactors and eight antineutrino detectors, each with good energy resolution, distributed among three experimental halls, supply a high-statistics sample of νe acquired at nine different baselines. This provides a unique platform to test the effects which arise from the wave packet treatment of neutrino oscillation. The modified survival probability formula was used to fit Daya Bay data, providing the first experimental limits: 2.38 • 10 −17 < σ rel < 0.23. Treating the dimensions of the reactor cores and detectors as constraints, the limits are improved: 10 −14 σ rel < 0.23, and an upper limit of σ rel < 0.20 is obtained. All limits correspond to a 95% C.L. Furthermore, the effect due to the wave packet nature of neutrino oscillation is found to be insignificant for reactor antineutrinos detected by the Daya Bay experiment thus ensuring an unbiased measurement of the oscillation parameters sin 2 2θ 13 and ∆m 2 32 within the plane wave model.

Decoherence, matter effect, and neutrino hierarchy signature in long baseline experiments

“…To be clear, environmentally induced decoherence is to be distinguished from neutrino wave-packet decoherence, a quantum wave effect that one may expect to occur based on known physics [13,14]. While wave-packet decoherence also introduces exponential damping factors that multiply the oscillatory terms in the oscillation transition probabilities, the damping depends strongly on the neutrino energy as well as on the baseline.…”

Nonmaximal θ23 Mixing at NOvA from Neutrino Decoherence

“…Neutrino wave packets have received abundant treatment from both relativistic quantum-mechanical and quantum-field theoretic perspectives [9]. In recent times the disappearance of reactor νe at nine different baselines of the Daya Bay experiment was examined for wave-packet effects, however none were found [10]. Neglecting higher-order dispersion-effect terms, there is general agreement concerning the basic form that neutrino wave-packet deco-herence would take [9,11].…”

Wave packets in QFT: leading order width corrections to decay rates and clock behaviour under Lorentz boosts

“…In [15] a wave packet analysis of quantum correlations in neutrino oscillations [16][17][18] was undertaken to extend previous work [19] that had been carried out using a plane wave analysis. The claim is that this wave packet analysis leads to a better agreement with the experimental results, most notably the MINOS experiments [20,21] (the corrections due to the wave packet are more negligible for the Daya Bay experiments [22,23]). In [24] neutrino wave packet effects for medium-baseline reactor neutrino oscillation (MBRO) experiments were also studied.…”