{
  "bibcode": "2008GCN..8348....1S",
  "body": "P. Schady (MSSL-UCL) and J. L. Racusin (PSU) report on behalf of the \nSwift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 081008 96 s \nafter the BAT trigger (Racusin et al., GCN Circ. 8344), using a newly \nimplemented observing sequence. The new sequence takes a 150s white-band \nfinding chart exposure, followed by a 250s u-band exposure, after which \nthe filter wheel rotates through all filters, taking short 20s exposures.\n\nA new fading source is detected at the ROTSE position (Rykoff et al., GCN \nCirc 8343) in the white, v, b, u and uvw1 filters, consistent with a� \nredshift of z=1.967 reported by Cucchiara et al., (GCN Circ 8346). The \nsource is decaying at a constant rate of 0.90+/-0.03 for the duration of \nintial UVOT observations, out to ~700s after the BAT trigger. The UVOT \nrefined position is\nRA(J2000) = 18:39:49.877 (279.95833 deg)\nDec(J2000) = -57:25:52.87 (-57.431111 deg)\nwith an estimated uncertainty of 0.6 arcsec (radius, 90% confidence).\n\nThe detections and 3 sigma upper limits of the fading afterglow are \nreported below, where T_start and T_stop represent the elapsed time since \nthe BAT trigger in seconds, and fc indicate finding chart exposures\n\nFilter      T_start(s) T_stop� Exp(s)�� Mag or 3 Sigma Limit\nwhite (fc)   96������ � 246���� 146���� �14.96 +/- 0.01\nwhite��������534��������554���� 19�������15.87 +/- 0.03\nu (fc)��� � �254������ �504�� ��246������15.19 +/- 0.02\nu����� � � � 658������ �678���� 19���� � 15.81 +/- 0.08\nv����� � � � 584��������604�����19����� �15.64 +/- 0.10\nb����������� 510������ �530�� ��19�������15.79 +/- 0.05\nuvw1�� � � � 633����� � 653�� ��19����� �17.03 +/- 0.22\nuvm2�������  608������ �1601����117����� > 19.16\nuvw2�� � � � 559��������1717��� 128������> 19.53\n\nThe above magnitudes are not corrected for the Galactic extinction \ncorresponding to a reddening of E(B-V) = 0.10 mag (Schlegel et al., 1998, \nApJS, 500, 525).� The photometry is on the UVOT photometric system \ndescribed in Poole et al. (2008, MNRAS, 383,627).",
  "circularId": 8348,
  "createdOn": 1223548254000,
  "email": "ps@mssl.ucl.ac.uk",
  "subject": "GRB081008: Swift/UVOT observations",
  "submitter": "Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>",
  "eventId": "GRB 081008"
}