GRB 210211A
GCN Circular 29515
Subject
GRB 210211A: ePESSTO+ NTT optical observations
Date
2021-02-16T18:08:56Z (5 years ago)
From
Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>
L. Harvey, M. Magee (TCD), P. D'Avanzo (INAF-OAB), D. B. Malesani (DTU Space), S. Prentice, M. Deckers (TCD), S. Schulze (OKC), J. Teffs (LJMU),
S. Gonzalez-Gaitan (CENTRA), J. Anderson (ESO), T. Muller Bravo (Southampton), T.-W. Chen (Stockholm), M. Gromadzki (Warsaw), C. Inserra (Cardiff),
E. Kankare (Turku), M. Nicholl (Birmingham), O. Yaron (Weizmann), D. Young (QUB), I. Manulis (Weizmann), report:
We observed the field of GRB 210211A (Fermi GBM Team, GCN Circ. 29470; Troja et al., GCN Circ. 29472) under the advanced extended Public ESO
Spectroscopic Survey for Transient Objects (ePESSTO+; see Smartt et al. 2015, A&A, 579, 40 http://www.pessto.org <http://www.pessto.org/> ). The observations were performed
on the ESO New Technology Telescope at La Silla with the EFOSC2 instrument in imaging mode on 2021-02-16 between 08:01:05 UT and 08:42:23 UT
(i.e. about 4.99 days from the burst). The observations were carried out with the R filter under a seeing of about 1.9".
The optical afterglow (D'Avanzo et al., GCN Circ. 29474; Lipunov et al. GCN Circ. 29477; Kuin et al., GCN Circ. 29485) is not detected down to a 3sigma
limiting magnitude of R ~ 24.3 (Vega; based on preliminary photometry calibrated against the USNO B1 catalogue).
GCN Circular 29485
Subject
GRB 210211A: Swift/UVOT Detection
Date
2021-02-11T22:59:12Z (5 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
N. P. M. Kuin (UCL-MSSL) and E. Troja (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210211A
78 s after the BAT trigger (Troja et al., GCN Circ. 29472). A source
consistent with the XRT position (Osborne et al. GCN Circ. 29478) and
the REM detection (d'Avanzo et al., GCN Circ. 29474)is detected in
the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 17:57:45.68 = 269.44035 (deg.)
Dec (J2000) = -46:16:01.6 = -46.26711 (deg.)
with an estimated uncertainty of 0.47 arc sec. (radius, 90% confidence).
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 78 227 147 17.89 +/- 0.06
white 596 611 15 >18.6
white 5391 5587 197 >20.3
v 4239 4438 197 >19.8
b 545 565 19 >18.4
u 290 489 196 >18.6
m2 4444 4491 47 >18.3
w2 4034 4234 197 >19.4
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.127 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 29484
Subject
GRB 210211A: Swift-XRT refined Analysis
Date
2021-02-11T22:28:35Z (5 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A. D'Ai (INAF-IASFPA), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto),
B. Sbarufatti (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAB), T.
Sbarrato (INAF-OAB) and E. Troja report on behalf of the Swift-XRT
team:
We have analysed 9.6 ks of XRT data for GRB 210211A (Troja et al. GCN
Circ. 29472), from 81 s to 40.6 ks after the BAT trigger. The data are
entirely in Photon Counting (PC) mode. The enhanced XRT position for
this burst was given by Osborne et al. (GCN Circ. 29478).
The light curve can be modelled with a power-law decay with a decay
index of alpha=1.15 (+0.09, -0.08).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.5 (+0.7, -0.6). The
best-fitting absorption column is 6.7 (+6.5, -3.6) x 10^21 cm^-2, in
excess of the Galactic value of 1.2 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum is 3.4 x 10^-11 (8.5 x 10^-11) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 6.7 (+6.5, -3.6) x 10^21 cm^-2
Galactic foreground: 1.2 x 10^21 cm^-2
Excess significance: 2.5 sigma
Photon index: 2.5 (+0.7, -0.6)
If the light curve continues to decay with a power-law decay index of
1.15, the count rate at T+24 hours will be 7.2 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.4 x
10^-14 (6.1 x 10^-14) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01032024.
This circular is an official product of the Swift-XRT team.
GCN Circular 29483
Subject
GRB 210211A: Swift-BAT refined analysis
Date
2021-02-11T20:52:22Z (5 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), E. Troja (NASA/GSFC/UMCP),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+600 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 210211A (trigger #1032024)
(Troja, et al., GCN Circ. 29472