GCN Circular 32656

N. P. M. Kuin (UCL-MSSL) and S. Dichiara (PSU) report on behalf

of the Swift/UVOT team:


The Swift/UVOT began settled observations of the field of

GRB 221009 179 s after the BAT trigger (Dichiara et al.,

GCN Circ. 32632
Not found
 
 
, and 32633
Not found
 
 
).  This GRB was initially reported as being

a new bright hard X-ray transient and named SwiftJ1913.1+1946.

Further analysis shows this is a GRB (Kennea et al, GCN Circ.

32635
Not found
 
 
, and 32651
Not found
 
 
).

The  preliminary UVOT position was reported in the Dichiara et al. GCN.

The GRB was also detected by Fermi (Veres et al. GCN Circ 32636;

Bissaldi et al. GCN Circ. 32637
Not found
 
 
; Lesage etal. GCN Circ. 32642
Not found
 
 
),

IPN (Svinkin et al.,  GCN Circ. 32641
Not found
 
 
); Agile (Ursi et al. GCN

Circ 32650). A redshift of 0.151 has been reported by de Ugarte

Postigo et al. (GCN Circ. 32648
Not found
 
 
), and optical detections were

reported also (MASTER: Lipunov et al., GCN Circ. 32634
Not found
 
 
 and 32639
Not found
 
 
;

Liverpool Telescope photometry and spectrum: Perley GCN Circ

32638;  VVS: Broens, GCN Circ. 32640
Not found
 
 
; BOOTES-2/TELMA: Hu et al., GCN

Circ. 32644
Not found
 
 
; Mondy: Belkin et al. GCN Circ. 32645
Not found
 
 
; MeerLICHT: de Wet et al.

GCN Circ. 32646
Not found
 
 
; Nanshan/NEXT photometry and Xinglong-2.16m

spectroscopy Xu et al. GCN Circ. 32647
Not found
 
 
; Al Khatim Observatory:

Odeh, GCN Circ. 32649
Not found
 
 
; REM: Brivio et al. GCN Circ. 32652
Not found
 
 
). Near IR

was reported for PRIME by Durbak et al. GCN Circ. 32654
Not found
 
 
 and radio

AMI-LA: Bright et al. GCN Circ. 32653
Not found
 
 
 and ATA:Farah et al.  GCN Circ. 32655
Not found
 
 
.

Pre-discovery limits from ZTF: Karambelkar et al. GCN Circ. 32643
Not found
 
 
.


Preliminary detections and 3-sigma upper limits using the UVOT photometric

system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early

exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white              179          329          147         16.68 +/- 0.03
v                  668          688           20         15.55 +/- 0.10
b                  593          613           20         17.05 +/- 0.11
u                  337          587          246         17.68 +/- 0.06
w1                 718         1293           58        >18.2
w2                 817         1219           39        >19.1

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 1.563 in the direction of the burst
(Schlegel et al. 1998).