Title :
Design of a Celestial Thomson-Scattering X-Ray Polarimeter
Author_Institution :
Columbia Astrophysics Laboratory Columbia University, New York, New York 10027
fDate :
6/1/1972 12:00:00 AM
Abstract :
A general discussion of the scientific importance and status of stellar x-ray polarimetry is presented. A stellar x-ray polarimeter designed to fit into the bottom half of the NASA Orbiting Solar Observatory-I (OSO-I) wheel compartment or other similar spacecraft is described. In this design, the linear polarization is obtained as a function of energy. The sensitivity of the polarimeter in the 4 - 24 keV energy range was optimized with the aid of a Monte Carlo simulation computer program and is given for several important celestial x-ray sources. Estimates of sensitivity thresholds for a much larger polarimeter, suitable for flight in the NASA High-Energy Astronomy Observatory (HEAO), are also given. The minimum detectable polarization for several x-ray sources is given. For example, the minimum detectable polarization at the 99% confidence level for the Crab nebula in a 24-h observation time is 1.4% for an OSO polarimeter in a compartment (50 Ã 30 Ã 30) cm and 0.27% for a HEAO polarimeter in a compartment (100 Ã 100 Ã 30) cm. These satellite experiments are feasible and will yield significant polarization results which will have an important bearing on our understanding of x-ray source mechanisms.
Keywords :
Astronomy; NASA; Observatories; Orbits (stellar); Polarimetry; Polarization; Space vehicles; Stellar motion; Wheels; X-ray detection;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.1972.4326767