GCN Circular 23725
Subject
GRB 190114C: Swift/UVOT Detection
Date
2019-01-15T19:59:02Z (5 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU) and J. D. Gropp (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190114C
74 s after the BAT trigger (Gropp et al., GCN Circ. 23688).
A source consistent with the XRT position
(Osborne et al. GCN Circ. 23704) and previously reported optical
detections (Tyurina et al., GCN Circ. 23690, Selsing et al., GCN Circ. 23695,
Izzy et al., GCN Circ. 23699, Bolmer & Schady, GCN Circ. 23702, Im et al.,
GCN Circ. 23717) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 03:38:01.16 = 54.50484 (deg.)
Dec (J2000) = -26:56:46.9 = -26.94637 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
The data of the first few orbits shows the afterglow to fade rapidly, particularly
in the NUV filters, which could be consistent with the heavy extinction reported by
Kann et al. (GCN Circ. 23710).
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 (fc) 74 224 147 14.89+/-0.02
white 566 586 19 16.90+/-0.07
white 5851 6050 196 19.19+/-0.09
white 21950 22857 885 20.22+/-0.09
v 616 627 10 16.28+/-0.19
v 16295 17136 820 18.97+/-0.13
v 26775 27682 885 19.41+/-0.24
v 39149 57221 1694 19.92+/-0.20
b 542 561 19 17.38+/-0.14
b 5646 5845 196 19.38+/-0.16
b 21038 46521 1591 20.83+/-0.26
u (fc) 286 536 245 17.58+/-0.07
u 33738 34038 295 >20.28
uvw1 4044 51522 3671 21.05+/-0.31
uvm2 3839 50615 3251 21.00+/-0.30
uvw2 6056 56384 3552 >21.33
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).