Normal incidence soft x-ray telescopes

Photos obtained during 5 mm of observation time from the flight of our 25-cm-diam normal-incidence soft x-ray (λ = 63.5 a) telescope on September 11, 1989, are analyzed and the data are compared to the results expected from tests of the mirror surfaces. These tests cover a range of spatial periods from 25 cm to 1 a. The photos demonstrate a resolution close to the photon shot noise limit and a reduction in the scattering of the multilayer mirror compared to a single surface for scattering angles above 1 arcmin, corresponding to surface irregularities with spatial penods below 10 μm. Our results are used to predict the possible performance of future telescopes: We conclude that sounding rocket observations might be able to reach a resolution around 0.1 arcsec. Higher resolutions will require flights of longer durations and improvements in mirror testing for the largest spatial periods.

[1]  Daniel G. Stearns,et al.  The scattering of x rays from nonideal multilayer structures , 1989 .

[2]  E. Spiller,et al.  Sub-arcsecond observations of the solar X-ray corona , 1990, Nature.

[3]  Eberhard Spiller.  Enhancement of the reflectivity of multilayer x-ray mirrors by ion polishing , 1990 .

[4]  Michael F. Kuechel,et al.  High-precision interferometric testing of spherical mirrors with long radius of curvature , 1991, Optics & Photonics.

[5]  Bruce E. Truax,et al.  Absolute Interferometric Testing Of Spherical Surfaces , 1989, Optics & Photonics.

[6]  Michael F. Kuechel,et al.  In-process metrology for large astronomical mirrors , 1990, Optics & Photonics.

[7]  Leon Golub,et al.  Filters for soft x-ray solar telescopes , 1990 .

[8]  Michael F. Kuechel.  New Zeiss interferometer , 1991, Optics & Photonics.

[9]  E. L. Church,et al.  The Prediction Of BRDFs From Surface Profile Measurements , 1990, Optics & Photonics.

[10]  Paul E. Glenn.  Robust, angstrom level circularity profilometry , 1990, Optics & Photonics.

[11]  James E. Harvey,et al.  Imaging capabilities of normal-incidence x-ray telescopes , 1990 .

[12]  R. Sinclair,et al.  Interfacial reactions on annealing molybdenum‐silicon multilayers , 1989 .

[13]  N. Ceglio,et al.  Thermally induced structural modification of Mo‐Si multilayers , 1990 .

[14]  Alan E. Rosenbluth,et al.  Determination Of Thickness Errors And Boundary Roughness From The Measured Performance Of A Multilayer Coating , 1986 .

[15]  Peter Z. Takacs,et al.  Long Trace Profile Measurements On Cylindrical Aspheres , 1989, Optics & Photonics.

[16]  R. Hoover,et al.  Soft X-ray Images of the Solar Corona with a Normal-Incidence Cassegrain Multilayer Telescope , 1988, Science.

[17]  Paul E. Glenn.  Angstrom level profilometry for submillimeter- to meter-scale surface errors , 1990, Optics & Photonics.

[18]  Steven R Lange.  Very High Resolution Profiler For Diamond Turning Groove Analysis , 1989, Optics & Photonics.

[19]  J. Zavada,et al.  Relationship between surface scattering and microtopographic features (A) , 1979 .

[20]  J. E. Manson.  Measurements of the solar spectrum between 30 and 128Å , 1972 .

[21]  Surface Roughness Evaluation of Multilayer Coated X-ray Mirrors by Scanning Tunneling Microscope , 1989 .