GRB 210212A
GCN Circular 29487
Subject
GRB 210212A: Swift detection of a burst
Date
2021-02-12T04:50:37Z (4 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
E. Troja (NASA/GSFC/UMCP), J. A. Kennea (PSU), N. J. Klingler (PSU),
H. A. Krimm (NSF), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester), D. M. Palmer (LANL), B. Sbarufatti (PSU),
M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:
At 04:25:18 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 210212A (trigger=1032183). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 72.261, +7.234 which is
RA(J2000) = 04h 49m 03s
Dec(J2000) = +07d 14' 01"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a
structure with a duration of about 50 sec. The peak count rate
was ~1200 counts/sec (15-350 keV), at ~6 sec after the trigger.
The XRT began observing the field at 04:27:00.9 UT, 103.0 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source with an enhanced position: RA, Dec 72.2666,
7.2693 which is equivalent to:
RA(J2000) = 04h 49m 03.99s
Dec(J2000) = +07d 16' 09.5"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 128 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
https://www.swift.ac.uk/sper. We cannot determine whether the source
is fading at the present time. No spectrum from the promptly downlinked
event data is yet available to determine the column density.
The initial flux in the 2.5 s image was 9.74e-10 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 250 seconds with the U filter starting
270 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the
XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The
8'x8' region for the list of sources generated on-board covers 100% of the XRT
error circle. The list of sources is typically complete to about 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.094.
Burst Advocate for this burst is E. Troja (eleonora.troja AT nasa.gov).
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)
GCN Circular 29489
Subject
GRB 210212A: Enhanced Swift-XRT position
Date
2021-02-12T10:44:09Z (4 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester)
report on behalf of the Swift-XRT team.
Using 478 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 210212A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 72.26662, +7.26968 which is equivalent
to:
RA (J2000): 04h 49m 3.99s
Dec (J2000): +07d 16' 10.8"
with an uncertainty of 3.7 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the
Swift-XRT team.
GCN Circular 29491
Subject
GRB 210212A: Swift-BAT refined analysis
Date
2021-02-12T14:38:20Z (4 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
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+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 210212A (trigger #1032183)
(Troja, et al., GCN Circ. 29487). The BAT ground-calculated position is
RA, Dec = 72.249, 7.215 deg which is
RA(J2000) = 04h 48m 59.7s
Dec(J2000) = +07d 12' 52.6"
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve showed a broad peak with some underlying
structure. It began around T-10 sec, peaked around T+5 sec and returned to
background by T+90 sec. T90 (15-350 keV) is 80.0 +- 35.8 sec (estimated
error including systematics).
The time-averaged spectrum from T-15.51 to T+80.49 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.85 +- 0.23. The fluence in the 15-150 keV band is 8.0 +- 1.2 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+7.99 sec in the 15-150 keV band
is 0.5 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1032183/BA/
GCN Circular 29492
Subject
GRB 210212A: Swift/UVOT Upper Limits
Date
2021-02-12T14:53:24Z (4 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 210212A
112 s after the BAT trigger (Troja et al., GCN Circ. 29487).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 29489)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 112 262 147 >20.6
u_FC 271 520 246 >20.3
white 112 930 242 >20.8
v 600 4588 236 >19.0
b 526 720 39 >19.3
u 271 868 285 >20.4
w1 650 4851 90 >19.1
m2 626 4793 235 >19.7
w2 93 4383 245 >19.7
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.094 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 29494
Subject
GRB 210212A: BOOTES-4/MET optical upper limit
Date
2021-02-12T15:40:39Z (4 years ago)
From
Youdong HU at IAA-CSIC <huyoudong072@hotmail.com>
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, M. A. Castro Tirado (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga), S. Guziy (Univ. of Nikolaev) and D. R. Xiong, Y. F. Fan, J. M. Bai, C. J. Wang, Y. X. Xin, X. H. Zhao (Yunnan Observatories of CAS) on behalf of a larger collaboration, report:
Following the detection of GRB 210212A by Swift (Troja et al. GCNC 29487), the 0.6m BOOTES-4/MET robotic telescope at Lijiang Astronomical Observatory (China) started to gather images after the twilight as soon as it was possible. No new source is detected within the Swift/XRT enhanced position (Beardmore et al. GCNC 29489) down to 19.7 mag in the co-added images (5x60 s, clear filer) starting at 13:11 UT on Feb 12. The non-detection is consistent with the limit reported by Swift/UVOT (Troja et al. GCNC 29487).
We thank the staff at Lijiang observatory for their excellent support.
GCN Circular 29495
Subject
GRB 210212A: Swift-XRT refined Analysis
Date
2021-02-12T16:18:16Z (4 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), D.N. Burrows (PSU),
K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U.
Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB), P. D'Avanzo
(INAF-OAB) and E. Troja report on behalf of the Swift-XRT team:
We have analysed 6.8 ks of XRT data for GRB 210212A (Troja et al. GCN
Circ. 29487), from 109 s to 34.2 ks after the BAT trigger. The data
comprise 337 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Beardmore et al. (GCN Circ. 29489).
The light curve can be modelled with an initial power-law decay with an
index of alpha=2.27 (+0.28, -0.50), followed by a break at T+194 s to
an alpha of 3.79 (+0.28, -0.23).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.55 (+0.13, -0.12). The
best-fitting absorption column is 1.6 (+0.6, -0.4) x 10^21 cm^-2,
consistent with the Galactic value of 1.1 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 4.4 x 10^-11 (5.0 x
10^-11) erg cm^-2 count^-1.
A summary of the WT-mode spectrum is thus:
Total column: 1.6 (+0.6, -0.4) x 10^21 cm^-2
Galactic foreground: 1.1 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index: 1.55 (+0.13, -0.12)
If the light curve continues to decay with a power-law decay index of
3.79, the count rate at T+24 hours will be 5.3 x 10^-10 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.3 x
10^-20 (2.6 x 10^-20) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01032183.
This circular is an official product of the Swift-XRT team.
GCN Circular 29496
Subject
GRB 210212A: MITSuME Akeno optical upper limits
Date
2021-02-12T16:58:03Z (4 years ago)
From
Katsuhiro L. Murata at Nagoya U <murata@u.phys.nagoya-u.ac.jp>
K. L. Murata, R. Adachi, R. Hosokawa, M. Niwano, F. Ogawa, N. Nakamura, N.
Ito, S. Ogata, H. Takamatsu, H. Hara, Y. Yatsu, and N. Kawai (TokyoTech)
report on behalf of the MITSuME collaboration:
We observed the field of GRB 210212A (Troja et al. GCN #29487, Beardmore et
al. GCN #29489, Palmer et al. GCN #29491, Kuin et al. GCN #29492, Hu et al.
GCN #29494, Tohuvavohu et al. GCN #29495) with the optical three color
(g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of
Akeno Observatory, Yamanashi, Japan. The observation with a series of 60
sec exposures started at 2021-02-12 08:51:45 UT(4.43 hours after the Swift
BAT trigger). We stacked the images with good conditions. We did not find
any new point sources within the enhanced Swift XRT circle (Beardmore et
al. GCN #29489) in all three bands.
We obtained the 5-sigma limits of the stacked images as follows.
T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
8.6 13:05:08 5400 g'>18.6, Rc>18.5, Ic>17.8
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used the PS1 catalog for flux calibration. The magnitudes are expressed
in the AB system. The images were processed in real-time through the
MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1,
Pages 4-24; https://github.com/MNiwano/Eclaire).
GCN Circular 29497
Subject
Swift GRB 210212A: Global MASTER-Net observations report
Date
2021-02-12T19:28:27Z (4 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin,
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov, D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),
D. Buckley
(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova
(Irkutsk State University, API),
A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko
(Blagoveschensk Educational State University)
MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 210212A ( E. Troja et al., GCN 29487) errorbox 53602 sec after notice time and 53674 sec after trigger time at 2021-02-12 19:19:52 UT, with upper limit up to 18.1 mag. The observations began at zenith distance = 44 deg. The sun altitude is -21.6 deg.
The galactic latitude b = -22 deg., longitude l = 191 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1545497
We obtain a following upper limits.
Tmid-T0 | Site |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________
53764 | MASTER-SAAO | C | 180 | 18.1 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 29498
Subject
GRB 210212A: Possible host galaxy counterpart with the NOT
Date
2021-02-12T22:31:32Z (4 years ago)
From
Kasper Elm Heintz at Univ. of Iceland and DAWN/NBI <keh14@hi.is>
K. E. Heintz (Univ. of Iceland), D. B. Malesani (DTU space), L. Izzo (DARK/NBI), and A. A. Djupvik (NOT), report on behalf of a larger collaboration:
We observed the field of GRB 210212A (Troja et al., GCN #29487), using the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Starting at 20:05:37 UTC on February 12, i.e. 15.5 hr after trigger, we obtained 3x600s exposures in the r-band. The observations were carried out under good conditions, with seeing around 0.8".
Within the refined Swift/XRT error circle (Beardmore et al., GCN #29489), we detect a faint, extended source with FWHM = 1.5". We measure r = 23.23 +/- 0.12 mag, calibrated against nearby field stars in the Pan-STARRS DR1 catalog. At the same position, we also tentatively detect a source in archival Pan-STARRS images.
This source is potentially the host galaxy of GRB 210212A. However, due to the relatively large uncertainty of the currently available XRT position (3.6"), we estimate a chance probability for this source to be unrelated to the GRB of P = 0.09 based on the formalism by Bloom et al. (2002, AJ, 123, 1111).
GCN Circular 29507
Subject
GRB 210212A: Gemini South optical observations
Date
2021-02-13T21:55:21Z (4 years ago)
From
Simone Dichiara at UMCP/NASA/GSFC <dichiara@umd.edu>
S.Dichiara (UMD, NASA-GSFC) and E. Troja (UMD, NASA-GSFC) report:
We observed the field of GRB 210212A (Troja et al., GCN Circ. 29487) with
the Gemini South telescope beginning 2021-02-13 02:16:45 UT, approximately
0.91 days post-burst. We obtained 9x120 s exposures in r-band performed
with good weather conditions and at an airmass of 1.5
Within the enhanced Swift-XRT error circle (Beardmore et al., GCN Circ.
29489) we detect a single extended source with r = 23.17 +/- 0.05 AB mag,
previously reported as the putative host galaxy (Heintz et al., GCN Circ.
29498).
A weak optical source with r = 25.3 +/- 0.2 AB mag lies at the edge of the
XRT error circle, 6 arcsec away from the putative host. We cannot determine
whether it is related to the GRB at present time.
Magnitudes are calibrated against the Pan-STARRS DR1 catalog and not
corrected for Galactic extinction.
We thank the Gemini South staff for rapidly executing these observations.
GCN Circular 29510
Subject
GRB 210212A: 1.3m DFOT Optical upper limit
Date
2021-02-15T18:26:17Z (4 years ago)
From
Rahul Gupta at ARIES, India <rahulbhu.c157@gmail.com>
Rahul Gupta, A. Kumar, Dimple, A. Ghosh, A. Aryan, B. Kumar, S. B.
Pandey, and K. Misra (ARIES) report:
We observed the field of Swift detected GRB 210212A (Troja et al., GCN
29487) with 1.3m Devasthal Fast Optical Telescope (DFOT) located at
Devasthal observatory of Aryabhatta Research Institute of
Observational Sciences (ARIES), India. The observations were started
on 2021-02-13 at 13:54:09 UT i.e. ~ 1.4 days after the BAT trigger. We
have taken multiple frames having an exposure time of 180 s in the R
filter. We did not detect any optical afterglow candidate within the
Swift/XRT enhanced position (Beardmore et al., GCN 29489).
We obtain the following 3-sigma upper limit in the stacked image.
Date Start_UT T_start-T0 (days) Filter Exp time (s) Limiting Magnitude
======================================================
2021-02-13 13:54:09 ~1.4 R 180*15 > 22.4
The magnitude is not corrected for the Galactic extinction in the
direction of the burst. Photometric calibration is performed using the
standard stars from the USNO-B1.0 catalogue.
This circular may be cited.
GCN Circular 29522
Subject
GRB 210212A: Mondy optical observations
Date
2021-02-18T00:17:06Z (4 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov (HSE)
report on behalf of GRB IKI FuN:
We observed the field of GRB 210212A (Troja et al., GCN 29487) with
AZT-33IK telescope of Sayan observatory (Mondy) starting on 2021-02-12
(UT) 14:39:29, i.e. 0.45 days after GRB trigger and reasonable FWHM of
about 2.7". Within enhanced XRT position (Beardmore et al., GCN 29489)
we found an object. Preliminary photometry of the object in a combined
image is following
Date UT start t-T0 Filter Exp. OT Err. UL(3sigma)
(mid, days) (s)
2021-02-12 14:39:29 0.44527 R 27*120 22.20 0.28 22.4
The photometry is based on the nearby USNO-B1.0 stars
USNO-B1.0_id R2
0972-0060540 15.06
0972-0060545 15.99
The object could be an afterglow of the GRB 210212A which is not
separated from (possible host) galaxy (Heintz et al., GCN 29498;
Dichiara et al., GCN 29507).
GCN Circular 29527
Subject
GRB 210212A: REM early-time optical/NIR upper limits
Date
2021-02-18T10:12:02Z (4 years ago)
From
Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>
P. D'Avanzo, S. Covino, D. Fugazza, A. Melandri (INAF-OAB) on behalf of the REM team, report:
We observed the field of GRB 210212A (Troja et al., GCN Circ. 29487) with the REM 60cm robotic
telescope located at the ESO premise of La Silla (Chile). The observations were performed starting
on 2021 February 12 at 04:27:01 UT (i.e. 103 seconds after the burst) at airmass 3.5 and were carried
in the g, r, i, z, H bands simultaneously.
From a preliminary analysis of the first set of images, obtained at a mid time of t-t0 = 150 s, we find no
source at the enhanced XRT position (Beardmore et al., GCN Circ. 29489) down to the following 3sigma
magnitude upper limits:
g > 18.2
r > 18.3
i > 17.4
z > 16.1
(AB; calibrated against the Pan-STARRS catalogue);
H > 15.8
(Vega; calibrated against the 2MASS catalogue).
GCN Circular 29540
Subject
GRB 210212A: Lowell Discovery Telescope observations
Date
2021-02-19T23:47:59Z (4 years ago)
From
Simone Dichiara at UMCP/NASA/GSFC <dichiara@umd.edu>
S.Dichiara (UMD, NASA-GSFC) and E. Troja (UMD, NASA-GSFC) report:
We observed the field of GRB 210212A (Troja et al., GCN Circ. 29487)
using the Large Monolithic Imager (LMI) on the 4.3m Lowell Discovery
Telescope (LDT) at Happy Jack, AZ. Observations started on February 19,
at 03:55:50 UT (about 7 days after the Swift trigger) with SDSS g, r, i
and z filters.
The extended source previously reported by Heintz et al. (GCN Circ.
29498) and Dichiara et al. (GCN Circ. 29507) is detected in all bands.
We measure a magnitude of r~23.3 +/- 0.2 AB calibrated against the
Pan-STARRS DR1 catalog and not corrected for Galactic extinction. A
comparison to earlier epochs shows no significant rebrightening.
We thank the staff of the Lowell Discovery Telescope for assistance with
these observations.