th / 0 10 20 06 v 1 2 F eb 2 00 1 On radiative muon capture in hydrogen
نویسنده
چکیده
We analyze the radiative capture of the negative muon in hydrogen using amplitudes derived within the chiral Lagrangian approach. Besides the leading order terms, given by the well-known Rood-Tolhoek Hamiltonian, we extract from these amplitudes the corrections of the next order in 1/M (M is the nucleon mass). In addition, we estimate within the same formalism also the ∆(1232) excitation effects and processes described by an anomalous Lagrangian. Using values of the parameters of the model obtained from the analysis of the pion photoproduction, which restricts the arbitrariness of the πN ∆ and γN ∆ vertices, we find that the model can explain up to half of the discrepancy between the PCAC value g P CAC P of the induced pseudoscalar constant g P and of g P extracted from the recent TRIUMF experiment. If these parameters are allowed to vary independently, the model can describe the high energy part of the experimental photon spectrum reasonably well for the values of g P ≈ g P CAC P .
منابع مشابه
n uc l - th / 9 71 10 53 v 1 2 5 N ov 1 99 7 USC ( NT ) - 97 - 09 , nucl - th / 9711053 Chiral Perturbation Theory
Chiral symmetry serves as a guiding principle in low-energy hadron dynamics. An effective lagrangian, which explicitly breaks chiral symmetry via a small mass term, allows for a systematic method of calculating higher order corrections to tree-level results. This is applied to radiative muon capture on hydrogen, and to proton-proton π 0 production near threshold. Both processes pose theoretical...
متن کامل0 41 00 42 v 1 2 9 O ct 2 00 4 Precision muon lifetime and capture experiments at PSI
a * on behalf of the µLan † and µCap ‡ Collaborations. The µLan experiment at the Paul Scherrer Institute will measure the lifetime of the positive muon with a precision of 1 ppm, giving a value for the Fermi coupling constant GF at the level of 0.5 ppm. Meanwhile, by measuring the observed lifetime of the negative muon in pure hydrogen, the µCap experiment will determine the rate of muon captu...
متن کامل0 41 00 42 v 2 3 1 O ct 2 00 4 Precision muon lifetime and capture experiments at PSI
a * on behalf of the µLan † and µCap ‡ Collaborations. The µLan experiment at the Paul Scherrer Institute will measure the lifetime of the positive muon with a precision of 1 ppm, giving a value for the Fermi coupling constant GF at the level of 0.5 ppm. Meanwhile, by measuring the observed lifetime of the negative muon in pure hydrogen, the µCap experiment will determine the rate of muon captu...
متن کاملth / 0 20 50 45 v 1 1 6 M ay 2 00 2 Low energy behavior of the astrophysical S - factor in radiative captures to loosely bound final states
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