[AAVSO-HEN] GRB 090709A: RAPTOR Limits During Gamma-Ray Emission

[grb at aavso.org]

The following is a GCN Circular circulated via the AAVSO network.
For an archive and more information on circulars visit:
http://lheawww.gsfc.nasa.gov/docs/gamcosray/legr/bacodine/gcn3_archive.html

TITLE:   GCN CIRCULAR
NUMBER:  9643
SUBJECT: GRB 090709A: RAPTOR Limits During Gamma-Ray Emission
DATE:    09/07/09 23:41:47 GMT
FROM:    James Wren at LANL  <jwren at nis.lanl.gov>

J. Wren, W.T. Vestrand, P.R. Wozniak, H. Davis, B. Norman
of Los Alamos National Laboratory report:

The RAPTOR telescope system responded to Swift trigger
356890 (Morris et al., GCN 9625) under good observing conditions.
Our narrow-field instruments began observing the location at
07:39:03.4 UTC, 28.8 s after the Swift trigger (7.1 s after
receipt of GCN message).  We obtained simultaneous observations
during the gamma-ray emitting interval in Cousins V, R, and I
bands as well as unfiltered data.  We do not detect the counterpart
observed by the Subaru Telescope (Aoki et al., GCN 9634) and
PARITEL (Morgan et al., GCN 9635).  The data from our unfiltered
and filtered systems was calibrated to the USNO-B1 catalog.  We
can put the following limits on the prompt emission:

t-mid(s)          exp(s)   filter  mag    mag-err
[since trigger]
----------------------------------------------------
31.34             5        clear  17.1   5 sigma limit
52.35             5        V      14.8   5 sigma limit
52.35             5        R      15.1   5 sigma limit
52.35             5        I      15.5   5 sigma limit
89.95             40       V      16.9   5 sigma limit