Burst locations with an arc second telescope (BLAST)

W. Neil Johnson III; Charles D. Dermer; J. E. Grove; Paul L. Hertz; Robert L. Kinzer; Richard A. Kroeger; James D. Kurfess; Michael N. Lovellette; G. Share; Mark S. Strickman; Kent S. Wood; Susan E. Inderhees; Bernard F. Phlips; Dieter H. Hartmann; Mark D. Leising; Gerald J. Fishman; Charles A. Meegan; Edward E. Fenimore

doi:10.1117/12.253994

Translator Disclaimer

18 October 1996 Burst locations with an arc second telescope (BLAST)

W. Neil Johnson III, Charles D. Dermer, J. E. Grove, Paul L. Hertz, Robert L. Kinzer, Richard A. Kroeger, James D. Kurfess, Michael N. Lovellette, G. Share, Mark S. Strickman, Kent S. Wood, Susan E. Inderhees, Bernard F. Phlips, Dieter H. Hartmann, Mark D. Leising, Gerald J. Fishman, Charles A. Meegan, Edward E. Fenimore

Author Affiliations +

Proceedings Volume 2806, Gamma-Ray and Cosmic-Ray Detectors, Techniques, and Missions; (1996) https://doi.org/10.1117/12.253994
Event: SPIE's 1996 International Symposium on Optical Science, Engineering, and Instrumentation, 1996, Denver, CO, United States

Abstract

Burst locations with an arc second telescope (BLAST) is a new mission concept being studied for NASA's medium explorer (MIDEX) mission opportunities. The principal scientific objectives of the BLAST mission are (1) to localize gamma- ray burst (GRB) positions to arcsec accuracy; (2) to search for enhancements in the rate of GRBs toward M31; and (3) to conduct the most sensitive sky survey to date of x-ray sources in the 7 - 200 keV regime. These objectives are achieved using a large array of position-sensitive scintillation detectors with a total area of 17,000 cm². This array is combined with a large field of view telescope (greater than 1 steradian) comprising two separate imaging systems. A coded aperture telescope provides arcminute source localization. For low energy x-rays (less than 50 keV), the aperture is also defined by phase modulation grids with provide complementary arcsecond information. The grid system consists of two aperture planes with 'checker board' patterns of slightly different pitch. The beating between the two grid pitches casts a broad interference pattern on the detector plane. Determining the phase of this interference pattern in both coordinates gives the location of a point source source in the sky, with aliased positions at approximately 1 arcmin spacing. The arcmin ambiguity is resolved by the coded aperture image. BLAST has a sensitivity to bursts of 0.03 photons cm^-2 s^-1, almost ten times more sensitive than BATSE. We expect to position 20 bursts per year to better than 2 arcsec accuracy and 35 bursts per year to better than 5 arcsec. BLAST will provide an all sky survey in hard x-rays with a sensitivity of 0.2 milliCrab at low energies.

Citation Download Citation

W. Neil Johnson III, Charles D. Dermer, J. E. Grove, Paul L. Hertz, Robert L. Kinzer, Richard A. Kroeger, James D. Kurfess, Michael N. Lovellette, G. Share, Mark S. Strickman, Kent S. Wood, Susan E. Inderhees, Bernard F. Phlips, Dieter H. Hartmann, Mark D. Leising, Gerald J. Fishman, Charles A. Meegan, and Edward E. Fenimore "Burst locations with an arc second telescope (BLAST)", Proc. SPIE 2806, Gamma-Ray and Cosmic-Ray Detectors, Techniques, and Missions, (18 October 1996); https://doi.org/10.1117/12.253994

ACCESS THE FULL ARTICLE