TITLE:   GCN CIRCULAR
NUMBER:  21948
SUBJECT: GRB 170823A: 15 GHz upper limits from AMI
DATE:    17/10/01 20:09:17 GMT
FROM:    Kunal Mooley at Oxford U  <kunal.mooley@physics.ox.ac.uk>

K. P. Mooley (Hintze Fellow, Oxford), T. D. Staley, R. P. Fender 
(Oxford), G. E. Anderson (Curtin), T. Cantwell (Manchester), D. 
Titterington, S. H. Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods, 
P. Scott (Cambridge), K. Grainge, A. Scaife (Manchester)

The AMI Large Array robotically triggered on the Swift alert for GRB 
170823A (Troja et al., GCN 21666) as part of the 4pisky program, and 
subsequent follow up observations were obtained up to 10 days 
post-burst. Our observations at 15 GHz on 2017 Aug 24.41, Aug 25.61 and 
Aug 26.58 (UT) do not reveal any radio source at the BAT location 
(Stamatikos et al., GCN 21678). While we are dynamic range limited due 
to a bright radio source in the vicinity of the GRB location, we are 
able to place 3sigma upper limits of 1.0 mJy, 1.1 mJy, and 0.8 mJy at 
the respective epochs.

We thank the AMI staff for scheduling these observations. The AMI-GRB 
database is a log of all GRB follow up observations with the AMI, and is 
available at http://4pisky.org/ami-grb/.