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Muitilayer and Grazing Incidence X-Ray/EUV Optics for Astronomy and Projection Lithography
| Content Provider | Semantic Scholar |
|---|---|
| Author | Hoover, Richard B. |
| Abstract | We have designed, analyzed, and are now fabricating an All-Reflecting H-Lyman a Coronagraph/Polarimeter for solar research. This new instrument operates in a narrow bandpass centered at A 1215.7 A-the neutral hydrogen Lyman a (Ly-a) line. It is shorter and faster than the telescope which produced solar Ly-a images as a part of the MSSTA payload that was launched on May 13, 1991. The Ly-a line is produced and linearly polarized in the solar corona by resonance scattering, and the presence of a magnetic field modifies this polarization according to the Hanle effect. The Lyman a Coronagraph/Polarimeter instrument has been designed to measure coronal magnetic fields by interpreting, via the Hanle effect, the measured linear polarization of the coronal Ly-a line. Ultrasmooth mirrors, polarizers, and filters are being flow-polished for this instrument from CVD silicon carbide substrates. These optical components will be coated using advanced induced transmission and absorption thin film multilayer coatings, to optimize the reflectivity and polarization properties at 1215.7/_. We describe some of the solar imaging results obtained with the MSSTA Lyman a coronagraph. We also discuss the optical design parameters and fabrication plans for the All-Reflecting H-Lyman a Coronagraph/Polarimeter. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19980213234.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
