GCN Circular 39355
Subject
LIGO/Virgo/KAGRA S250206dm: observation in AbAO, optical transient near NED/GLADE+ galaxy WISEA J021210.14+514821.7
Date
2025-02-17T20:20:56Z (5 days ago)
From
Alexei Pozanenko at IKI, Moscow <grb.alex@gmail.com>
Via
email
A. Pozanenko (IKI, HSE), A. Volnova (IKI), N. Pankov (HSE, IKI), R. Ya.
Inasaridze (AbAO) report on behalf of IKI GRB-FuN collaboration:
We continue to observe galaxies from the NED/GLADE+ catalogs in the
localization volume S250206dm (LIGO Scientific Collaboration, GCN 39175;
LIGO Scientific Collaboration, GCN 39184).
We observed several galaxies with AS-32 telescope of the Abastumani
Observatory (AbAO) in the R-filter. The observations consist of 3 exposures
in R-filter of each galaxy in the on Feb., 12 and Feb. 16. In the first
epoch of observations near the galaxy WISEA J021210.14+514821.7 we clearly
detected an optical source which is not present in the PS1 catalog. The
source is visible in each of the 3 exposures. The source is not detected in
the following epoch on February 16. Preliminary photometry of stacked
images is the following
Date |UTstart |t-T0* |MJD_mid |Exp. |Filter|OT |Err |UL |FWHM
| |(mid, days)| |(n*s) | | | |(3sigma)|"
----------------------------------------------------------------------------
2025-02-12|15:46:10| 5.76573|60718.65844| 3*60 |R |18.15|0.21|19.0 |3.1
2025-02-16|15:57:48| 9.77361|60722.66632| 3*60 |R | n/d |n/d |19.1 |3.0
* - T0 = 21:25:30.439 UTC LIGO trigger time of S250206dm
Photometry is based on nearby stars from USNO-B1.0:
ID RA Dec R2
1418-00067499 02:12:12.126 +51:49:52.59 14.68
1418-00067498 02:12:12.025 +51:48:41.88 14.94
1418-00067549 02:12:18.069 +51:48:21.33 13.93
The source coordinates are (J2000) 02:12:10.17 +51:48:21.54, and the offset
from the center of the galaxy is 6.2", which is equivalent to 11 kpc at a
luminosity distance of DL = 457 Mpc (GLADE+).
We have not observed this galaxy before, so we cannot say anything about
the nature of this source and further observations and analysis of further
observations of this galaxy are needed.