in this discretionary time proposal we request iso observations of the recently detected gamma-ray burst (grb), grb970111 within the next 4 weeks in order to search for flaring and/or fading infrared emission associated with the burst source. gamma-ray bursts represent one of the great unsolved mysteries in modern astrophysics. they are intense, energetic flashes of gamma- rays which occur randomly on the sky at a rate of roughly one per day and which can last from a few millisec to hundreds of seconds. there is as yet no unambiguous distance measure to the grb sources - they may be in an extended galactic halo or they may be at cosmological distances. there is, however, a growing body of circumstantial evidence favouring a cosmological origin. a statistical association between grb error boxes and luminous near-ir galaxies has been identified. the bepposax x-ray satellite imaged the intense grb of january 11, 1997 with its wide field camera,to a precision of 10. radius. the error box has now been further reduced by triangulation with ulysses and batse to a strip of size 20.x6.. the rapid availability of such an accurate grb location is unprecedented in the history of gamma-ray astronomy and opens a new window for potential discovery. the fact that iso is in orbit at this time provides a unique opportunity to exploit this new capability to the utmost. the occurrence of such an ideal candidate for observation with iso could not have been foreseen at the time of the supplemental call. we therefore propose to use iso to raster the 20.x6. error box of grb970111 within the next 4 weeks, before the target disappears from iso.s view, to search for flaring and/or fading activity associated with this grb. members of this team have extensive ground-based campaigns already underway to study this grb at radio and optical wavelengths. no ir measurements have ever been obtained within such a short time of the grb occurrence and no instrument has ever had iso.s unparalleled capabilities. by using virgul3 hours of iso time for this task, we may detect that which has eluded a generation of ground-based observers at all wavelengths i.e. a direct grb counterpart, which would provide us with both a distance measure and a burst host.
Instrument
PHT22
Temporal Coverage
1997-02-24T07:16:18Z/1997-02-24T07:34:16Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, HANLON et al., 1998, 'SEARCH FOR A FLARING\/FADING IR COUNTERPART TO THE NEW GAMMA-RAY BURST comma GRB970111', 1.0, European Space Agency, https://doi.org/10.5270/esa-rrvys2j
