[vsnet-grb-info 9742] GRB 100902A: UKIRT JK Observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11210
SUBJECT: GRB 100902A: UKIRT JK Observation
DATE:    10/09/05 07:10:32 GMT
FROM:    Myungshin Im at Seoul Nat U  <mim at astro.snu.ac.kr>

  Myungshin Im, Changsu Choi, Hyunsung Jun, Eugene Kang (CEOU/Seoul
  National University), Y. Urata (NCU), P. Choi (Pomona College),
  and  T. Sakamoto (NASA/GSFC), on behalf of a larger collaboration

   We observed GRB 100902A (Sakamoto et al. GCN 11181) in J and K filters
  using UKIRT. The observation started at Sept. 04, 14:24:39 UT or roughly
  1.79 days after the BAT alert.
   The reduced images with non-optimal calibration frames do not show a clear
  sign of the afterglow candidate reported in Updike et al.
  (GCN 11209), although both the J and K images show a faint smudge at
  the reported location which may corresponds to the afterglow.
   The significance of the detection is only ~3 sigma (J ~ 20.8 mag,
  K ~ 19 mag in Vega), therefore it is difficult to draw a firm conclusion
  on detection or non-detection of the afterglow in our data. Further
  analysis of the UKIRT data is ongoing.