Fine pitch CdTe-based hard-X-ray polarimeter performance for space science in the 70–300 keV energy range

Abstract

a b s t r a c t X-rays astrophysical sources have been almost characterized through imaging, spectroscopy and timing analysis. Nevertheless, more observational parameters such as polarization are needed because some radiation mechanisms present in gamma-ray sources are still unclear. We have developed a CdTe based fine-pitch imaging spectrometer, Caliste to study polarization. With a 58-micron pitch and 1 keV energy resolution at 60 keV, we are able to accurately reconstruct the polarization angle and fraction of an impinging flux of photons which are scattered by 90°after Compton diffusion within the crystal. In this paper, we present the principles and the results obtained for this kind of measurements: on one hand, we compare simulations results with experimental data taken at ESRF ID15A (European Synchrotron Radiation Facility) using a 35-300 keV mono-energetic polarized beam. Applying a judicious energy selection to our data set, we reach a remarkable sensitivity level characterized by a measured Quality factor of 0.78 7 0.02 in the 200-300 keV range; and a measured Q factor of 0.6470.0 at 70 keV where hard X-rays mirrors are already available.

Lead borate glasses and synergistic impact of lanthanum oxide additive: optical and nuclear radiation shielding behaviors

“…Due to the broad range composition, high homogeneity, and transparency of glass materials, they have considered promising in radiation protection. Many applications have been used in the energy with a range from 15 to 300 keV such as the dental clinics, radiation protection spectacles, research laboratories, radiotherapy X-ray rooms [12].…”

“…Fig 12. Half-value layer (HVL) values as a function of photon energy of La5 glass sample (this work), concretes [Ordinary concrete (OC), hematite-serpentine (HSC), ilmenite-limonite (ILC), basalt-magnetite (BMC), ilmenite (IC) and steel-scrap (SSC)][17] and other glasses (G1 and G2)[18] …”