GCN Circular 31390

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
Not found
 
 
) also 
detected by Fermi/LAT (M. Arimoto et al. 2022, GCN 31350
Not found
 
 
), AGILE (A. 
Ursi et al. 2022, GCN 31354
Not found
 
 
), and Fermi/GBM (Lesage et al. 2022, GCN 
31360
Not found
 
 
)  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
Not found
 
 
; Kuin & Tohuvavohu, GCN 31351
Not found
 
 
; Fu et al., 
GCN 31353
Not found
 
 
; Hentunen et al., GCN 31356
Not found
 
 
; Perley et al., GCN 31357
Not found
 
 
; de 
Ugarte Postigo et al., GCN 31358
Not found
 
 
; Fynbo et al., GCN 31359
Not found
 
 
; Vinko et al., 
GCN 31361
Not found
 
 
; Tomasella et al., GCN 31363
Not found
 
 
; Mao et al., GCN 31364
Not found
 
 
; Noschese 
et al., GCN 31366
Not found
 
 
; Mao et al., GCN 31368
Not found
 
 
; Guelbenzu, et al., GCN 31370
Not found
 
 
; 
Strausbaugh et al., GCN 31371
Not found
 
 
, D'Avanzo et al., GCN 31373
Not found
 
 
; Strausbaugh 
et al., GCNs 31383
Not found
 
 
, 31389
Not found
 
 
; Dimple et al., GCN 31384
Not found
 
 
; Romanov, GCN 31387
Not found
 
 
; 
Caballero-Garcia, GCN 31388
Not found
 
 
).    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
Not found
 
 
; Fynbo et al., GCN 
31359
Not found
 
 
; Tomasella et al., GCN 31363
Not found
 
 
).