The advanced X-ray astrophysics facility (AXAF)

Abstract

NASA's Advanced X-ray Astrophysics Facility (AXAF) will be an orbiting X-ray observatory, designed to address fundamental questions in astronomy and astrophysics. Its importance derives from the fact that many of the fundamental processes in space are associated with high energy particles that radiate mainly X-rays, and that the AXAF will be extremely sensitive to X-ray emission. The United States National Academy of Sciences' Astronomy Survey Committee assigned AXAF as its highest priority among major new astronomy projects in recognition of the AXAF's scientific potential. AXAF is the successor to NASA's second High Energy Astronomy Observatory, the Einstein X-ray Observatory, which operated from 1978 to 1981. Like the Einstein, the AXAF will be built around a grazing incidence telescope capable of forming X-ray images. AXAF, however, will go far beyond the Einstein in capability having ∼ 10 times the angular resolution, ∼ 100 times the sensitivity for imaging, and up to ∼ 1000 times the sensitivity for spectroscopy. The AXAF will operate in space for 15 years, and be maintained and refurbished by use of NASA's Space Station. An AXAF observer program will make the great majority of the data available to the entire scientific community.