Thermal Limit Spectroscopy as a Goal for X-ray Astronomy

Abstract

The R~300-1000 grating spectra from XMM-Newton and Chandra are a radical advance, allowing spectroscopic physics techniques to be applied to X-ray astronomy, revolutionizing a wide range of research. Ten years on these spectra will be routine, and higher resolution will be needed. I propose ``Thermal Limit Spectroscopy'' as the next natural goal for X-ray spectroscopy. This will open up new physics: plasma physics, velocity widths, Doppler shifts, line profiles, and absorption lines in photoionized plasmas. A resolution of R=3000-10,000 is required, and the technology is within reach.

4 pages, 0 figures. to be published in the proceedings of `New Century of X-ray Astronomy' revised to clarify `temperatures' used; also corrected typos, minor text changes