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

Abstract

The disappearance of reactorν e 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 ofν e 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 (which corresponds to σ x 10 −11 cm) 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 Δm 2 32 within the plane wave model.

Decoherence in neutrino propagation through matter, and bounds from IceCube/DeepCore

“…These decoherence effects differ from the standard decoherence caused by the separation of wave packets (see e.g. [20,21]) and might arise, instead, from quantum gravity effects [22][23][24]. Throughout this work, for brevity, we will refer to such non-standard decoherence simply as decoherence.…”

Entangled neutrino states in a toy model QFT

“…This means that they depend on the momentum only via Lorentz scalars. The covariant wave packet hypothesis was assumed in the experimental analysis of decoherence at Daya Bay [4]. We believe that our QFT approach will allow a robust test of these claims.…”

“…Furthermore, the degradation of the signal observed by JUNO would be considerable [3]. This possibility has been rejected by the Daya Bay collaboration [4]. However their study relied upon a neutrino wave packet model.…”

Connection between νn→ν¯n¯ reactions and n−Hao1 2020Phys. Rev. D3010View full textAdd to dashboardCite

“…Although we have explained that (α w m ν ) 3 /π is a reasonable approximation to |ψ ν (0)| 2 with the help of the wavepacket assumption [92][93][94][95] and the Lorentz invariance requirement, as a matter of fact, it can be obtained by a direct replacement of electron mass (m e ) and electromagnetic fine structure constant (α) with the neutrino mass (m ν ) and the weak interaction strength (α w ) respectively from the relevant expression used for H-H oscillations in Refs. [18,19,32,85].…”