Gamma-ray line emission is a direct probe of the nucleosynthesis that occurs in Type Ia supernovae. In this work we describe the wealth of information obtainable from observations of this emission. Advanced Compton telescope designs are being studied by the Naval Research Laboratory, with the goal being the construction of a telescope which would be capable of detecting SNe Ia to distances in e...

We have developed radiation detectors using the new synthetic diamonds. The diamond detector has an advantage for observations of ”low/medium” energy gamma rays as a Compton telescope. The primary advantage of the diamond detector can reduce the photoelectric effect in the low energy range, which is background noise for tracking of the Compton recoil electron. A concept of the Diamond Compton T...

A model dielectric function is derived for TiO2 based on reflection electron energy loss spectroscopy data and photoabsorption cross sections. The model is based on a set of Mermin oscillators. The input data is dominated by excitations at low momentum transfer, i.e. near the optical limit. Surprisingly the dielectric function derived at low momentum transfer describes the Compton profile quite...

Exclusive two-photon reactions such as Compton scattering at large angles, deeply virtual Compton scattering, and hadron production in photon-photon collisions provide important tests of QCD at the amplitude level, particularly as measures of hadron distribution amplitudes and skewed parton distributions. Invited talk presented at Photon 2000 Ambleside, England August 26–31, 2000 ∗Work supporte...

Compton scattering by pion: there is no room for the off–shell effects. Abstract We show that the off–shell contributions in Compton scattering by pion may exist only in the single exchange diagrams. These contributions are canceled completely in the total gauge–invariant amplitude as it confirmed by one–loop calculations. It explains, in particular, some results of the chiral pertubation theor...

Static nucleon polarisabilities gauge the stiffness of the nucleon against an external electro-magnetic field, parameterising the part of the real Compton amplitude at zero energy which is not explained by the pole terms, i.e. by the successive interactions of two photons with a point-like nucleon of anomalous magnetic moment κ. Dynamical nucleon polarisabilities are the energy dependent genera...

We present the results from a Chandra observation of the powerful radio galaxy 3C 265. We detect X–ray emission from the nucleus, the radio hotspots and lobes. In particular, the lobe X–ray emission is well explained as anisotropic inverse Compton scattering of the nuclear photons by the relativistic electrons in the radio lobes; the comparison between radio synchrotron and IC emission yields a...

Anharmonic thermal effects on the electron momentum distribution of a lithium fluoride single crystal are experimentally measured through high-resolution Compton scattering and theoretically modeled with ab initio simulations, beyond the harmonic approximation to the lattice potential, explicitly accounting for thermal expansion. Directional Compton profiles are measured at two different temper...

In a previous paper virtual Compton scattering off the nucleon has been investigated in the one–loop approximation of the linear sigma model in order to determine the 3 scalar generalized polarizabilities. We have now extended this work and calculated the 7 vector polarizabilities showing up in the spin–dependent amplitude of virtual Compton scattering. The results fulfill 3 model–independent c...

Supercritical accretion flows inevitably produce radiation-pressure driven outflows, which will Compton up-scatter soft photons from the underlying accretion flow, thereby making hard emission. We perform two dimensional radiation hydrodynamic simulations of supercritical accretion flows and outflows, incorporating such Compton scattering effects, and demonstrate that there appears a new hard s...