arXiv subjects

V. Gudkov

Publications and source records attributed to V. Gudkov.

23 records · Page 2Linked to original sources

arXiv2006

General classification and analysis of neutron beta-decay experiments

A method for the general analysis of the sensitivities of neutron beta-decay experiments to manifestations of possible deviations from the Standard model is proposed. In a consistent fashion, we take into account all known (radiative and recoil) corrections which are incorporated within the Standard Model to provide a description of angular correlations in neutron decay in the first order of approximation, or down to the level of $\sim 10^{-5}$. The contributions from models beyond the Standard model are, for low energy neutron decay, parameterized in terms of vector, axial-vector, scalar and tensor coupling constants and in terms of parameters related to specific models. For the present analysis we derive the exact expressions for the neutron beta decay probability which includes all possible manifestations models beyond the Standard Model down to level of $\sim 10^{-5}$ without time-reversal violation. Based on the general expressions for manifestation of the deviations from the standard model, we present analysis of the sensitivities for selected neutron decay experiments.

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arXiv2004

Neutron beta decay in effective field theory

Radiative corrections to the lifetime and angular correlation coefficients of neutron beta-decay are evaluated in effecitive field theory. We also evaluate the lowest order nucleon recoil corrections, including weak-magnetism. Our results agree with those of the long-range and model-independent part of previous calculations. In an effective theory the model-dependent radiative corrections are replaced by well-defined low-energy constants. The effective field theory allows a systematic evaluation of higher order corrections to our results to the extent that the relevant low-energy constants are known.

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arXiv2002

Neutrino-deuteron reactions at solar neutrino energies

In interpreting the SNO experiments, accurate estimates of the νd reaction cross sections are of great importance. In our recent work, we have improved our previous calculation by updating some of its inputs and by incorporating the results of a recent effective-field-theoretical calculation. The new cross sections are slightly (\sim 1%) larger than the previously reported values. It is reasonable to assign 1% uncertainty to the νd cross sections reported here; this error estimate does not include radiative corrections.

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arXiv2002

Neutrino-deuteron reactions at solar neutrino energies

In interpreting the SNO experiments, very accurate estimates of the νd reaction cross sections are of great importance. We improve the previous estimates of our group by updating some of its inputs and by taking into account the results of a recent effective-field-theoretical calculation. The new cross sections are slightly (\sim 1%) larger than the previously reported values. We present arguments that lead to the conclusion that it is reasonable to assign 1% uncertainty to the νd cross sections reported here.

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arXiv2000

Neutrino Reactions on Deuteron

The cross sections for the ν-d and \barν-d reactions are calculated for the incident energy up to E_ν= 170 MeV, with the use of a phenomenological Lagrangian approach. We assess and improve the reliability of the employed calculational method by examining the dependence of the results on various input and approximations that go into the calculation. The main points of improvements over the existing work are: (1) use of the "modern" NN potentials; (2) use of the more accurate nucleon weak-interaction form factors; (3) monitoring the strength of a vertex that governs the exchange-current contribution, with the use of data on the related process, n+p\to d+γ. In addition to the total cross sections, we present various differential cross sections that are expected to be useful for the SNO and other experiments. In the low energy regime relevant to the solar neutrinos, the newly calculated total cross sections agree with the existing literature values. The origins of slight differences found for higher energies are discussed. The ratio between the neutral-current and charged-current reaction cross sections is found to be extremely stable against any variations in the input of our calculation.

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