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GCN Circular 28171

GRB 200729A: Spitzer archival source detection
2020-07-30T00:50:11Z (4 years ago)
Tanmoy Laskar at U of Bath <>
T. Laskar (U. of Bath), E. Berger (Harvard), C. Kilpatrick (UCSC), W. Fong,
R. Margutti, R. Chornock, A. Hajela, K. Alexander, D. Coppejans
(Northwestern) report:

"In an archival observation of NGC4242 by the Spitzer Space Telescope on
2012-08-06 (PI: van Zee), we find a point-like source coincident with the
enhanced X-ray position of GRB 200729A (Osborne et al, GCN 28168).
Photometry is complicated by the variable background; preliminary analysis
suggests the object has a flux density of ~ 11 uJy (21.3 AB mag), about 1
mag brighter than the NOT r/z limits (Malesani et al., GCN 28169).

Further analysis is in progress."
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