Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 31390

GRB 220101A: Mondy optical observations
2022-01-05T13:03:41Z (2 years ago)
Alexei Pozanenko at IKI, Moscow <>
S. Belkin (IKI, HSE), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov 
(HSE)  report  on behalf of GRB IKI FuN:

We observed Swift GRB 220101A (Tohuvavohu, et al., GCN 31347) also 
detected by Fermi/LAT (M. Arimoto et al. 2022, GCN 31350), AGILE (A. 
Ursi et al. 2022, GCN 31354), and Fermi/GBM (Lesage et al. 2022, GCN 
31360)  with AZT-33IK telescope of Sayan observatory (Mondy)  starting 
on 2022-01-04  (UT) 15:16:32.  We detect the optical afterglow 
(Tohuvavohu et al., GCN 31347; Kuin & Tohuvavohu, GCN 31351; Fu et al., 
GCN 31353; Hentunen et al., GCN 31356; Perley et al., GCN 31357; de 
Ugarte Postigo et al., GCN 31358; Fynbo et al., GCN 31359; Vinko et al., 
GCN 31361; Tomasella et al., GCN 31363; Mao et al., GCN 31364; Noschese 
et al., GCN 31366; Mao et al., GCN 31368; Guelbenzu, et al., GCN 31370; 
Strausbaugh et al., GCN 31371, D'Avanzo et al., GCN 31373; Strausbaugh 
et al., GCNs 31383, 31389; Dimple et al., GCN 31384; Romanov, GCN 31387; 
Caballero-Garcia, GCN 31388).    Preliminary photometry of the afterglow 
in a stacked image is following

Date       UT start   t-T0       Filter Exp.   OT    Err.  UL(3sigma)
                     (mid, days)        (s)

2022-01-04 12:36:19   3.33083    R      30*120 21.50 0.12  23.1

The photometry is based on the nearby SDSS-DR12 stars
RA DEC R(Lupton)
00:05:20.64408 +31:45:46.0728 18.562
00:05:34.81464 +31:45:50.5224 15.734
00:05:32.53944 +31:44:51.9396 15.369
00:05:36.69864 +31:44:42.4176 14.677

We searched for the nearest galaxy in catalogs. The nearest galaxy was 
found in Legacy Survey 1.5 arcsec apart  from afterglow UVOT position 
with r=23.98, z=21.33 and not detected in g-filter (Brick: 0013p317, 
Objid: 4276). The galaxy is not presented in SDSS and PS1 catalogs. This 
red galaxy might be a host galaxy of GRB 220101A, in this case the 
distance from the source to the center of the galaxy will be about 10 
kpc at redshift z = 4.618 (Fu et al., GCN 31353; Fynbo et al., GCN 
31359; Tomasella et al., GCN 31363).
Looking for U.S. government information and services? Visit