Search for Unpredicted Gamma-ray Lines with INTEGRAL/SPI
Abstract
ESA's INTEGRAL mission was launched in October, 2002. The on-board Spectrometer SPI is the most sensitive high resolution gamma-ray spectrometer thus far flown in space. We have undertaken a global search of the SPI data for unpredicted gamma-ray lines. Photon counts in each detector are summed per pointing. We analyze the summed spectra with software we developed. We identify some lines due to isotopes with long half-life times, and radiation damage of the space craft. We realize that imperfect gain corrections cause some difficulties for this study in high energy (> 4 MeV). We also point out that minor solar flares are sources of strong lines such as the 4.4 MeV Carbon line. We report preliminary upper limits on temporally and spatially varying gamma-ray line fluxes.
- Publication:
-
AAS/High Energy Astrophysics Division #8
- Pub Date:
- August 2004
- Bibcode:
- 2004HEAD....8.1625W