The Hubble Space Telescope's High-Speed Photometer
R. C. Bless, E. E. Richards, A. Bosch, J. F. Dolan, J. L. Elliot,
M. Nelson, J. W. Percival, E. L. Robinson, M. Taylor, G. W. Van Citters,
and R. L. White
We present an overview of the performance of the High Speed Photometer
(HSP). one of the five original instruments on the Hubble Space
Telescope (HST).
As its name implies, the HSP was designed for precise high time resolution
photometry from visual to ultraviolet wavelengths; sample times as
short as 10.7 microseconds were possible.
Three image dissectors along with 23 different broad- and narrowband filters
spanning the spectral range from 1200 to 7500 Å were used for
photometry of stars and glalaxies.
A fourth image dissector with associated polarization analyzers allowed
the measurement of broadband linear polarization at near-ultraviolet
wavelengths.
Simultaneous observations in the blue and red could be made using one
of the dissectors and a photomultiplier.
Except for an instability in the sensitivity of one of the image
dissectors and a reduced throughput in a specialized observational mode,
the instrument met or exceeded operational specifications until it was
removed from HST in 1993 December.
The ability of HSP to carry out its primary program, however, was nearly
totally compromised by the poor performance of the telescope, i.e.,
the spherical aberration of the primary mirror that greatly amplified
the effects of large spacecraft pointing jitter and telesceop "breathing."
As a consequence, the real possibility of HST/HSP opening a new
era of astronomical photometry was lost.
HSP data affected by various telescope problems, as well as data in
which these complications were relatively small, are shown.
The excellent condition of the HSP after its return to Earth is
described briefly.