Grazing incidence telescopes for x-ray astronomy

Abstract

Downloaded From: http://opticalengineering.spiedigitallibrary.org/ on 05/15/2015 Terms of Use: http://spiedl.org/terms Abstract. With grazing incidence telescopes, x-ray astronomy became a major branch of astrophysics. They are an indispensable tool in the study of >10 6 K thermal and non-thermal high energy phenomena occurring in objects from the solar system to the most distant sites in the universe. They have shed light upon dark matter and dark energy. Four cosmic missions with focusing grazing incidence x-ray telescopes based upon the Wolter 1 geometry are currently in space. They include two observatory class facilities launched in 1999, NASA's high resolution x-ray and ESA's high throughput XMM-Newton. Two others are Japan's Suzaku, performing a variety of studies, and the Swift XRT, which finds precise positions for the x-ray afterglows of gamma-ray bursts. Four new cosmic missions with Wolter-like focusing telescopes are scheduled for launch. They will provide much broader bandwidth (NuSTAR and Astro-H), perform a new sky survey with more exposure time and a broader energy range than previous surveys (eROSITA), have an imaging detector with much better energy resolution (Astro-H), and measure polarization (GEMS). The Kirkpatrick-Baez and the lobster-eye are two types of potentially useful grazing incidence telescopes that have not yet been in orbit. It may not be possible to improve upon Chandra's 0.5 arcsec resolution without new technology.

Measurement of Freeform Optical Surfaces: Trade‐Off between Accuracy and Dynamic Range

“…The X‐ray beam below the critical grazing angle undergoes near total “external” reflection because the index of refraction of a metal is less than 1 in the X‐ray band. [ 210 ] The grazing‐incidence mirror is consequently very long in tangential direction and has very tight tolerance for the surface slope error. The slope error is required to be in the range of 50 nrad RMS with mirror length up to 1 m [ 211 ] for the third‐generation synchrotron and free electrons laser radiation sources.…”

Effective algorithm for ray-tracing simulations of lobster eye and similar reflective optical systems

“…ISS-Lobster [8][9][10] and others, e.g. [11][12][13][14][15][16][17]. It is currently being used in other applications, e.g.…”

Development of low-density coatings for soft x-ray reflectivity enhancement for ATHENA and other missions

“…Several technologies are available and used for the fabrication of X-ray telescopes. Most widespread technologies are nickel electroformed replica monolithic optics with gold reflecting coating (used also as a separation agent in the replication process), and platinum or iridium coatings, deposited on figured glass substrates 1,2 (monolithic or segmented). Iridium coating on silicon plates is also the technology that will be used for the ATHENA (ESA) and Lynx (NASA) missions [3][4][5] .…”