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GCN Circular 32758

GRB 221009A: Pan-STARRS optical photometry
2022-10-14T21:35:08Z (2 years ago)
Ken Smith at Queen's University Belfast <>
M. Huber, A. Schultz, K. C. Chambers (IfA, Hawaii), K. W. Smith,
M. Fulton, S. J. Smartt (QUB), T.-W. Chen (Stockholm), M. Nicholl
(Birmingham), D. R. Young, L. J. Shingles, S. Srivastav, S. Sim (QUB),
T. de Boer, J. Bulger, J. Fairlamb, C.-C. Lin, T. Lowe, E. Magnier,
R. J. Wainscoat, H. Gao (IfA), C. Stubbs (Harvard), A. Rest (STScI)

Daily imaging has been acquired (weather permitting) of the optical
counterpart of Swift J1913.1+1946 (Dichiara et al., GCN 32632;
Lipunov et al.,GCN 32634), the optical afterglow of GRB 221009A
(Kennea & Williams, GCN 32635; Veres et al., GCN 32636) with
Pan-STARRS2 since MJD 59863 (2022-10-11).  The following table
shows the most recent observations.

MJD          filter mag    dmag
59866.22756  r      20.92  0.05
59866.22504  i      19.88  0.02
59866.22371  z      19.21  0.02
59866.22239  y      18.77  0.03

We observed an initial fade of approximately 0.9 mags per day in
i, z and y, slowing to about 0.4 mags per day in these filters
over the last 2 days.
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