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GCN Circular 11819

GRB 101225A: revised analysis of narrow band imaging
2011-03-22T19:16:23Z (13 years ago)
Nial Tanvir at U.Leicester <>
N. R. Tanvir (U. Leicester) and A. J. Levan (U. Warwick) report:

We have re-reduced and re-analysed more thoroughly the imaging reported
in GCN 11642. While it remains the case that the optical transient is
detected in the H-alpha narrow-band filter, and at best marginally present
in the r-band, the significance of the excess H-alpha detection is reduced.��
Within the associated errors the revised photometry is broadly consistent
with the red colour of the transient at this time (the narrow-band filter being
somewhat redward of the central wavelength of the r-band filter), and hence,
the data do not require significant line emission. This argument for a z~0
origin is therefore weakened.
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