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arXiv · 0903.1713

Fermi/LAT discovery of gamma-ray emission from the flat-spectrum radio quasar PKS 1454-354

LAT Collaboration·A. A. Abdo·P. G. Edwards·M. M. Chester·D. N. Burrows·M. Hauser·S. Wagner
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Abstract

We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope of high-energy gamma-ray (GeV) emission from the flat-spectrum radio quasar PKS 1454-354 (z=1.424). On 4 September 2008 the source rose to a peak flux of (3.5 +/- 0.7)x 10^-6 ph cm^-2 s^-1 (E > 100 MeV) on a time scale of hours and then slowly dropped over the following two days. No significant spectral changes occurred during the flare. Fermi/LAT observations also showed that PKS 1454-354 is the most probable counterpart of the unidentified EGRET source 3EG J1500-3509. Multiwavelength measurements performed during the following days (7 September with Swift; 6-7 September with the ground-based optical telescope ATOM; 13 September with the Australia Telescope Compact Array) resulted in radio, optical, UV and X-ray fluxes greater than archival data, confirming the activity of PKS 1454-354.

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LAT Collaboration, A. A. Abdo, P. G. Edwards, M. M. Chester, D. N. Burrows, M. Hauser, S. Wagner. 2009-03-10. Fermi/LAT discovery of gamma-ray emission from the flat-spectrum radio quasar PKS 1454-354. https://doi.org/10.1088/0004-637x%2F697%2F1%2F934

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