[vsnet-grb-info 15541] GRB 140916B: LOT and iPTF follow-up of optical afterglow candidates

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16830
SUBJECT: GRB 140916B: LOT and iPTF follow-up of optical afterglow candidates 
DATE:    14/09/18 02:13:09 GMT
FROM:    Kuiyun Huang at ASIAA  <ljhuang at asiaa.sinica.edu.tw>

GRB 140916B: LOT and iPTF follow-up of optical afterglow candidates

L. P. Singer (Caltech), K.Y. Huang (NCU/NTNU/ASIAA), Y. Urata (NCU),
V. Bhalerao (IUCAA), M. M. Kasliwal (Carnegie Observatories/Princeton),
and S. B. Cenko (NASA/GSFC) report on behalf of a larger collaboration:

We have continued to observe the optical afterglow candidates reported by
iPTF (Singer et al., GCN 16822) in connection with GRB 140916B, which was
detected by Fermi. We obtained images of iPTF14fok with the Lulin
One-meter Telescope (LOT), the Palomar 48-inch Oschin telescope (P48), and
the robotic Palomar 60-inch telescope (P60). We report the following
observations, relative to the time of the burst:

  LOT, +13.16 hours:   r = 19.87 +/- 0.18
  P60, +29.67 hours:   r = 19.02 +/- 0.22

The source has not faded significantly from the initial P48 detection 4.17
hours after the burst of R = 19.57 +/- 0.07 mag. We therefore conclude
that it is unrelated to the GRB, possibly an old foreground supernova.

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