Microvariability survey with the Hubble Space Telescope Fine Guidance Sensors: Exploring the instrumental properties

Autor(en)

Rainer Kuschnig, Werner Wolfgang Weiss, R Gruber, Pierre Yves Bely, Helmut Jenkner

Abstrakt

The suitability of the Hubble Space Telescope (HST) Fine Guidance Sensors (FGS) for a magnitude limited survey of microvariability among guide stars is investigated. The linearity, relative sensitivity, and dead-time constants of the three FGSs are determined, and the photon noise limitation of the FGS photometry is confirmed. The noise spectrum is found to be "white" and a procedure is described which provides an estimate of the mean noise amplitude for any guide star observation. We derive a criterion, given a specific probability, to predict an upper limit for peaks in the amplitude spectrum of time series. We give examples for constant, known variable, and new variable guide stars, and illustrate that our FGS noise model will permit the automatic detection of microvariability within our survey of HST data. Presently, the lowest noise level found in FGS data obtained between November 1992 and December 1993 is 200 ppm, but better data by an order of magnitude are expected to be obtainable during the life-time of HST.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Space Telescope Science Institute

Journal

Astronomy & Astrophysics

Band

328

Seiten

544-550

Anzahl der Seiten

7

ISSN

0004-6361

Publikationsdatum

1997

Peer-reviewed

Ja

ÖFOS 2012

103003 Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/microvariability-survey-with-the-hubble-space-telescope-fine-guidance-sensors-exploring-the-instrumental-properties(df228df6-7c08-46b6-a515-19f7b35c36bf).html