Radiative muon capture on

Radiative muon capture on carbon, oxygen, and calcium

“….10: Photon energy spectrum from40 Ca, 0.6 mm converter, compared to the best fits from the spectrum fitting method. 'Chr' refers to the theory of Christillin[82], 'GOT' to that of Gmitro et al[73] and 'PP' to the Primakoff polynomial.measurements for G>57 and the present results. Despite this agreement, there is some variation in the extracted values of g p /g a • The individual experiments have used somewhat different techniques, and they will be discussed in some detail below.…”

“…Gmitro [82] for RMC on 16 0. Again, the GDR and GQR were considered as sim- The results of these microscopic calculations were somewhat distressing; for both 16 0 and 40 Ca the RMC/OMC predictions were approximately a factor of two larger than the earlier phenomenological calculations [82,81] for the same value of gp . In addition, the microscopic results indicated a much greater dependence of RMC on gp than obtained in the phenomenological approach.…”

“…Photon energy spectrum from40 Ca, 1.0 mm converter, compared to the best fits from the spectrum fitting method. 'Chr' refers to the theory of Christillin[82], 'GOT' to that ofGmitro et al [73] and 'PP' to the Primakoff polynomial. spectrum fitting method is more sensitive to inaccuracies in the detector response function.…”

Induced pseudoscalar coupling of the proton weak interaction

“…Like 40 Ca, both phenomenological calculations and microscopic calculations are available, but similarly the sensitivities of results to approximations are difficult to estimate. Taking g p /g a ≃ 6.7 the phenomenological calculation of Christillin and Gmitro (1985) gave R γ = 2.08, the shell model calculation of Gmitro et al (1986) gave R γ = 1.61 in MIA and R γ = 3.10 in IA and sum rule calculation of Roig and Navarro (1990) gave R γ = 1.73. Again, with the exception of the IA result, these are reasonably consistent with the experimental result (Bergbusch et al, 1999) R γ = 1.67 ± 0.18 with the sum rule and MIA approaches implying roughly the canonical value of g p /g a and the approach of Christillin and Gmitro (1985) requiring a somewhat smaller value.…”

“…The MIA start out too low for 12 C, implying a large value of g p /g a , and rise with increasing A to become significantly too high for the Ni isotopes, implying there a small value of g p /g a . The phenomenological calculations of Christillin (1981) and Christillin and Gmitro (1985) for 16 O and 40 Ca are both too high and the sum rule calculations show no consistent pattern. It appears clear that we are not yet at a stage where theoretical uncertainties are sufficiently under control to consistently reproduce experimental results.…”