TITLE:   GCN CIRCULAR
NUMBER:  12462
SUBJECT: GRB 111020A: BOOTES-3 Optical Upper Limit.
DATE:    11/10/20 15:07:24 GMT
FROM:    Juan Carlos Tello at IAA-CSIC  <jtello@iaa.es>

J. C. Tello (IAA-CSIC), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), A. J.
Castro-Tirado, J. Gorosabel (IAA-CSIC), on behalf of a larger collaboration,
report:

We have observed the field of the short GRB 111020A, detected by Swift/BAT
(Palmer et al., GCNC 12460) with the 0.6m Yock-Allen telescope at the
BOOTES-3 station in Blenheim (New Zealand). Unfiltered images were obtained
starting 69.72 minutes after the burst (07:43:32 UT), no new source is
visible in the co-added image with total exposure 6900 sec (115 images
ending in 09:40:53 UT), the limiting magnitude for the combined image is R =
19.5 (calibrated against USNO B1.0).

USNO B1-0519-0893471, a catalogued R=18.7 magnitude source is at the edge of
the XRT circle but shows no evident variability.