Radiative corrections are crucial for modern high-precision physics experiments, and are an area of active research in the experimental and theoretical community. Here we provide an overview of the state of the field of radiative corrections with a focus on several topics: lepton-proton scattering, QED corrections in deep-inelastic scattering, and in radiative light-hadron decays. Particular emphasis is placed on the two-photon exchange, believed to be responsible for the proton form-factor discrepancy, and associated Monte-Carlo codes.
View Article and Find Full Text PDFPhys Rev Lett
December 2012
We present a new dispersive formulation of the γZ box radiative corrections to weak charges of bound protons and neutrons in atomic parity violation measurements on heavy nuclei such as 133Cs and 213Ra. We evaluate for the first time a small but important additional correction arising from Pauli blocking of nucleons in a heavy nucleus. Overall, we find a significant shift in the γZ correction to the weak charge of 133Cs, approximately 4 times larger than the current uncertainty on the value of sin2 θ(W), but with a reduced error compared to earlier estimates.
View Article and Find Full Text PDFWe present a new formulation of one of the major radiative corrections to the weak charge of the proton-that arising from the axial-vector hadron part of the γZ box diagram, ℜe□(γZ)(A). This formulation, based on dispersion relations, relates the γZ contributions to moments of the F(3)(γZ) interference structure function. It has a clear connection to the pioneering work of Marciano and Sirlin, and enables a systematic approach to improved numerical precision.
View Article and Find Full Text PDFThe presence of a near-haploid karyotype is a rare finding in human malignancies, most frequently occurring in acute leukemia. In solid tumors, a near-haploid karyotype has been reported in fewer than 40 cases. We report two nearly identical near-haploid karyotypes from two distinctly different tumor types.
View Article and Find Full Text PDFWe calculate the effects on the elastic electron-proton scattering cross section of the two-photon exchange contribution with an intermediate Delta resonance. The Delta two-photon exchange contribution is found to be smaller in magnitude than the previously evaluated nucleon contribution, with an opposite sign at backward scattering angles. The sum of the nucleon and Delta two-photon exchange corrections has an angular dependence compatible with both the polarization-transfer and the Rosenbluth methods of measuring the nucleon electromagnetic form factors.
View Article and Find Full Text PDFTwo-photon exchange contributions to elastic electron-proton scattering cross sections are evaluated in a simple hadronic model including the finite size of the proton. The corrections are found to be small in magnitude, but with a strong angular dependence at fixed Q2. This is significant for the Rosenbluth technique for determining the ratio of the electric and magnetic form factors of the proton at high Q2, and partly reconciles the apparent discrepancy with the results of the polarization transfer technique.
View Article and Find Full Text PDFPhys Rev C Nucl Phys
September 1993
Phys Rev C Nucl Phys
September 1989
Phys Rev C Nucl Phys
December 1987
To determine whether the carcinogenicity of dinitrotoluene (DNT) in rodent bioassays was predictive for humans, we examined the mortality experience of exposed workers at two ammunition plants. Cohorts of 156 and 301 men who had worked a month or more during the 1940s and 1950s at jobs with opportunity for substantial DNT exposure were followed through the end of 1980. Numbers of expected deaths and standardized mortality ratios (SMRs) were computed, using mortality rates of US white males as the standard.
View Article and Find Full Text PDFSeven funeral homes were surveyed in 1980 to determine the magnitude of embalmers' exposure to formaldehyde, other chemical vapors, and total and respirable particulates. Air was monitored for formaldehyde by personal and area samples, and assayed using the chromotropic acid method. Personal sampling revealed time-weighted average formaldehyde concentrations which ranged from 0.
View Article and Find Full Text PDFStandardized respiratory disease questionnaires and pulmonary function tests were administered to licensed white male morticians attending an educational program in Morgantown, W.Va. Detailed occupational histories were obtained; included were estimates of the numbers of bodies personally embalmed.
View Article and Find Full Text PDFSperm count distributions among exposed and control groups at a dibromochloropropane (DBCP) manufacturing plant were remarkably similar. Yet reproductive histories from 60 exposed men obtained in conjunction with the semen analyses indicated that fertility had been reduced during exposure. Ratios of observed to expected births or standardized fertility ratios (SFRs) were computed for reproductive experience at parities of 1 or greater.
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