English

The Burst Alert Telescope (BAT) on the Swift MIDEX Mission

Astrophysics 2009-11-11 v1

Abstract

The Burst Alert Telescope (BAT) is one of 3 instruments on the Swift MIDEX spacecraft to study gamma-ray bursts (GRBs). The BAT first detects the GRB and localizes the burst direction to an accuracy of 1-4 arcmin within 20 sec after the start of the event. The GRB trigger initiates an autonomous spacecraft slew to point the two narrow field-of-view (FOV) instruments at the burst location within 20-70 sec so to make follow-up x-ray and optical observations. The BAT is a wide-FOV, coded-aperture instrument with a CdZnTe detector plane. The detector plane is composed of 32,768 pieces of CdZnTe (4x4x2mm), and the coded-aperture mask is composed of approximately 52,000 pieces of lead (5x5x1mm) with a 1-m separation between mask and detector plane. The BAT operates over the 15-150 keV energy range with approximately 7 keV resolution, a sensitivity of approximately 10E-8 erg*cm^-2*s^-1, and a 1.4 sr (half-coded) FOV. We expect to detect >100 GRBs/yr for a 2-year mission. The BAT also performs an all-sky hard x-ray survey with a sensitivity of approximately 2 mCrab (systematic limit) and it serves as a hard x-ray transient monitor.

Keywords

Cite

@article{arxiv.astro-ph/0507410,
  title  = {The Burst Alert Telescope (BAT) on the Swift MIDEX Mission},
  author = {S. D. Barthelmy and L. M. Barbier and J. R. Cummings and E. E. Fenimore and N. Gehrels and D. Hullinger and H. A. Krimm and C. B. Markwardt and D. M. Palmer and A. Parsons and G. Sato and M. Suzuki and T. Takahashi and M. Tashiro and J. Tueller},
  journal= {arXiv preprint arXiv:astro-ph/0507410},
  year   = {2009}
}

Comments

18 Pages, 12 Figures, To be published in Space Science Reviews