GCN Circular 37974
Subject
GRB 241030A: Swift/UVOT Detection
Event
Date
2024-10-30T15:42:42Z (2 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
Via
email
A.A. Breeveld (UCL-MSSL) and N. J. Klingler (GSFC/UMBC/CRESSTII) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 241030A 83s after the BAT trigger (Klingler et al., GCN Circ. 37956) and Fermi/GBM trigger (Fermi GBM team, GCN Circ. 37955).
A fading source consistent with the XRT position (Beardmore et al., GCN Circ. 37962) and the optical counterpart (Watson et al., GCN 37957; Fernández-Rodríguez et al., GCN 37958; Zheng et al., GCN 37959; An et al., GCN 37960; Higuchi et al., GCN 37963; Qiu et al., GCN 37965 and Wu et al., GCN 37970), is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 22:52:33.47 = 343.13946 (deg.)
Dec (J2000) = +80:26:59.8 = 80.44995 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
Preliminary detections 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 83 232 147 15.43 ± 0.02
white 575 595 19 13.80 ± 0.05
white 748 768 20 14.19 ± 0.04
v 625 645 19 13.71 ± 0.05
b 551 571 20 13.96 ± 0.04
u 295 545 246 12.96 ± 0.02
w1 674 694 20 14.09 ± 0.06
m2 650 670 20 14.57 ± 0.10
w2 601 621 20 15.34 ± 0.11
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.131 in the direction of the burst (Schlegel et al. 1998).