TITLE:   GCN CIRCULAR
NUMBER:  32338
SUBJECT: GRB 220706A: Optical observations from NOT
DATE:    22/07/07 07:06:31 GMT
FROM:    Antonio de Ugarte Postigo at OCA  <deugarte@oca.eu>

A. de Ugarte Postigo, (OCA), D.B. Malesani (Radboud Univ. and DAWN/NBI),
and A. Kasikov (NOT, Aarhus Univ, Univ. of Tartu) report on behalf of a larger
collaboration,

We observed the field of GRB 220706A (D’Ai et al. GCN 32329) with AlFOSC 
on the 2.5m NOT telescope at Roque de los Muchachos Observatory (La 
Palma, Spain). The observation started at 04:33 UT (11.68 hrs after the burst) 
and consisted on 3x300s imaging in r-band and 5x200s in z-band.

No new object is detected within the refined XRT error box (Evans et al. GCN 
32330) in neither of the bands. The 3-signa detection limit in the r-band is 
24.5 mag and 23.6 in z-band, calibrated with respect to Pan-STARRS field 
stars. Our non detection is consistent with previous reports (Gendre et al. 
GCN 32331, Lipunov et al. GCN 32332, Jiang et al. GCN 32335).

We do note that there is a faint source at the Northern edge of the error box, 
at a distance of ~2.9“ from the centre of the XRT position, which is also 
marginally detected in the Pan-STARRS images, and for which we measure 
a magnitude of 24.1+/-0.3, with coordinates (J2000):

R.A.: 00:02:25.01
Dec.: -16:24:37.0