[vsnet-grb-info 4035] GRB 061122: Candidate Optical Afterglow

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  5849
SUBJECT: GRB 061122: Candidate Optical Afterglow
DATE:    06/11/24 05:00:33 GMT
FROM:    Jules Halpern at Columbia U.  <jules at astro.columbia.edu>

J. P. Halpern & E. Armstrong (Columbia U.) report on behalf of the
MDM Observatory GRB follow-up team:

"We obtained R-band observations of the field of INTEGRAL GRB 061122
(Mereghetti et al., GCN 5834) on two consecutive nights using the
MDM 2.4m telescope.  Within 1" of the Swift XRT candidate X-ray
afterglow (Beardmore et al., GCN 5842), we find a fading object at

        (J2000) R.A.=20h15m19.84s, Decl.=+15d31'02.5"

with positional uncertainty ~0.5", and the following magnitudes:

    ------------------------------------------------
     Date(UT)  Mid-time(UT)  t-t0(hr)   R(mag) +/-
    ------------------------------------------------
     Nov. 23      01:52       17.9      22.61  0.05
     Nov. 24      02:26       42.5      23.41  0.15
    ------------------------------------------------

We propose this as the optical afterglow of GRB 061122.

Magnitudes are referenced to the USNO B1.0 star at
(J2000) R.A.=20h15m18.48s, Decl.= +15d31'05.5" with R=17.61,
and are not corrected for Galactic extinction, A_R=0.49 mag
in this direction (Schlegel et al. 1998).

MDM images of the field are posted at

http://www.astro.columbia.edu/~jules/grb/061122/

This message may be cited."