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GCN Circular 8159

SGR 0501+4516: WHT observations of the possible near-infrared counterpart
2008-08-29T10:34:57Z (16 years ago)
Nanda Rea at U of Amsterdam <>
N. Rea (U. Amsterdam), E. Rol (U. Leicester), P.A. Curran (U.
Amsterdam), I. Skillen (Isaac Newton Group), D.M. Russell (U.
Amsterdam), G.L. Israel (INAF) on behalf of a larger collaboration

On 2008 August 25 we observed the new Soft Gamma-ray Repeater SGR
0501+4516 with LIRIS, the near-infrared imager on the William Herschel
Telescope (WHT) in La Palma. The observations were performed in the Ks
band with a total exposure time of 1.8 hours.

We clearly detect one object within the refined XRT error circle (GCN 
8148), at the position:

05:01:06.74  +45:16:34.1 (J2000)

with an uncertainty of 0.25 arcseconds (with respect to 2MASS 
astrometry). This is consistent with being the UKIRT suggested nIR 
counterpart (GCN 8126). We find the object at a magnitude of 19.2+/-0.2 
(with respect to 2MASS calibration), slightly fainter than the UKIRT 
detection. We plan to take further observations from WHT in a few days 
to confirm this very tentative nIR variability.

We wish to thank Chris Benn and Rene Rutten for promptly approving our 
Target of Opportunity request.
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