{
  "bibcode": "2008GCN..8564....1H",
  "body": "S. T. Holland (CRESST/GSFC/USRA), P. A. Evans (U Leicester),\nF. E. Marshall (NASA/GSFC), P. Schady (MSSL), and R. Margutti (U\nBicocca & OAB) report on the behalf of the Swift UVOT team:\n\n      We confirm the optical afterglow of GRB 081126 reported by\nSergeev & Pozanenko (2008, GCN Circ. 8558). A re-examination of the\nUVOT data shows that there is a fading source at\n\n      RA (J2000)  21:34:03.59  =  323.51496 (deg)\n     Dec (J2000) +48:42:38.3   =  +48.71064 (deg)\n\nwith an estimated uncertainty of 0.5 arcsec (radius, 90% confidence,\nstatistical + systematic).  This is consistent with the XRT error\ncircle.  Preliminary photometry and 3-sigma upper limits for this\nsource are\n\nFilter   T_start   T_stop   Exp(s)     Mag   Err\n------------------------------------------------\n  white        75      225     147     18.82 0.09\n     u        289      420     127     18.17 0.13\n\n     v       5161     5361     197     19.29 0.32\n     b       4546     4746     197     20.20 0.28\n     u       5778     5976     197    >20.4\n   uvw1      5572     5771     197    >20.0\n   uvm2      5366     5566     197    >19.6\n   uvw2      4957     5156     197    >20.0\n  white      4751     4951     197     20.33 0.21\n------------------------------------------------\n\nThe quoted upper limits have not been corrected for the expected\nGalactic extinction along the line of sight corresponding to a\nreddening of E_{B-V} = 0.78 mag (Schlegel, et al., 1998, ApJS, 500,\n525).  All photometry is on the UVOT photometric system described in\nPoole et al. (2008, MNRAS, 383, 627).  The detection in the u filter,\ncombined with the lack of detections in the UV filters, is consistent\nwith the afterglow having a redshift of approximately 2.4 < z < 3.8.\nHowever, this result is uncertain due to the large Galactic reddening\nalong the line of sight to this source.\n\n      The source identified in Holland & Margutti 2008, (GCN\nCirc. 8559) as being possibly extended is consistent with the\ncatalogued position of the 2MASS point source 21340333+4842361.  The\nseparation between this 2MASS source and the afterglow is 3.2 arcsec.\nSince the photometry of the 2MASS source and the afterglow are\nconsistent with both sources having at the same redshift it is\npossible that the 2MASS source is the host galaxy.  Further\nobservations are encouraged to confirm or reject this hypothesis.\n\n      Holland & Margutti 2008, (GCN Circ. 8559) misidentified the\noptical afterglow as as the 2MASS point source 21340333+4842361.  We\napologize for any confusion caused by the misidentification in the\nprevious UVOT Circular on GRB 081126.",
  "circularId": 8564,
  "createdOn": 1227801379000,
  "email": "Stephen.T.Holland@nasa.gov",
  "subject": "GRB 081126: Confirmation of the Optical Afterglow",
  "submitter": "Stephen Holland at USRA/NASA/GSFC/SSC  <Stephen.T.Holland@nasa.gov>",
  "eventId": "GRB 081126"
}