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Fulton, M. A.

Publications and source records attributed to Fulton, M. A..

Intensity distribution of the X-ray source for the AXAF VETA-I mirror test

Intensity distribution measurements of the X-ray source for the AXAF VETA-I mirror test are reported. During the VETA-I test, microscope pictures were taken for each used anode immediately after it was brought out of the source chamber. The source sizes and the intensity distribution structures are shown. They are compared and shown to agree with the results from pinhole camera measurements. It is demonstrated that under operating conditions characteristic of the VETA-I test, all the source sizes have an FWHM of less than 0.45 mm. For a source of this size at 528 m away, the angular size to VETA is less than 0.17 arcsec, which is small compared to the on-ground VETA angular resolution. These results were crucial for VETA data analysis and for obtaining the on-ground and predicted in-orbit VETA point response function.

Zhao, Ping↗

Microstrip proportional counter development at MSFC

Microstrip detectors are an exciting new development in proportional counter design fabricated using integrated circuit-type photolithography techniques; they therefore offer very high spatial accuracy and uniformity. A development program is underway at NASA-Marshall to produce large-area microstrips for use in an X-ray detector balloon flight program and to investigate the general performance limits of these new devices. Microstrips tested so far have been fabricated both in-house using standard photolithographic techniques and by an outside contractor using electron beam technology. Various substrate materials have been tested along with different electrode configurations. The distributions of pickup on subdivided cathodes on both top and bottom surfaces of the microstrips are also being investigated for use as two-dimensional imaging detectors. Data from these tests in the development of a large-area device will be presented.

Fulton, M. A.↗