GRB 220606B
GCN Circular 32177
Subject
GRB 220606B: Gemini South Optical Observations
Date
2022-06-08T00:14:35Z (4 years ago)
From
Brendan O'Connor at UMD <oconnorb@umd.edu>
B. O'Connor (UMD/GWU), E. Troja (Tor Vergata), S. Dichiara (PSU),
on behalf of a larger collaboration:
We performed target of opportunity observations of the short
GRB 220606B (Fermi GBM Team GCN 32165, Tohuvavohu et al. GCN 32167)
with the Gemini Multi Object Spectrograph (GMOS) mounted on the
Gemini-South telescope. We obtained imaging in r-band and z-band
for 630 s in each filter starting at ~1.4 d post-trigger.
The GMOS field of view covers the central ~45% of the BAT error
circle (Tohuvavohu et al. GCN 32170). We note that this includes
a bright nearby galaxy with an estimated distance of 225 Mpc
(GLADE catalog; Dalya et al. 2016).
In comparison to the Dark Energy Survey DR2 catalog (Abbott et al.
2021), we do not identify any uncatalogued sources to a depth
r>25 AB mag and z>24.5 AB mag. This is in agreement with the
previously reported limit from Swift/UVOT (Evans et al. GCNs
32168 and 32173).
Our observations are sensitive to an AT2017gfo-like kilonova
at 225 Mpc. Therefore, either GRB 220606B is not physically
associated with the nearby galaxy or its kilonova is ~25 times
fainter than AT2017gfo at 1.4 d post-merger.
We thank the staff of the Gemini Observatory, in particular
Steve Margheim and Joan Font-Serra, for rapid scheduling of
these observations.
GCN Circular 32174
Subject
GRB 220606B: Fermi GBM Observation
Date
2022-06-07T16:22:44Z (4 years ago)
From
Boyan A. Hristov at UAH <bah0046@uah.edu>
B. Hristov (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:
"At 01:03:28.68 UT on 06 June 2022, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB 220606B (trigger 676170213 / 220606044),
which was also detected by the Swift/BAT-GUANO (Tohuvavohu et al. 2022,
GCN 32167).
The Fermi GBM Final Real-time Localization (GCN 32165) is consistent
with the GUANO position.
The GBM light curve shows a single peak with a duration (T90) of about
0.9 +/- 0.4 s (50-300 keV).
The time-averaged spectrum from T0-0.256 s to T0+0.768 s is best fit by
a simple power law with index = -1.28 +/- 0.07.
The event fluence (10-1000 keV) in this time interval is
(2.9 +/- 0.4)E-7 erg/cm^2. The 0.64-sec peak photon flux measured
starting from T0-0.064 s in the 10-1000 keV band is
2.8 +/- 0.9 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM
Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular 32173
Subject
GRB 220606B: Swift follow-up observations
Date
2022-06-07T13:36:38Z (4 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), M.G. Bernardini
(INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), D.N.
Burrows (PSU), J. D. Gropp (PSU), J.A. Kennea (PSU), P.A. Evans (U.
Leicester), A. Breeveld (UCL-MSSL) report on behalf of the Swift team:
Swift-XRT has performed follow-up observations of the
Swift/BAT-GUANO-detected burst GRB 220606B (Tohuvavohu et al., GCN
Circ. 32167), collecting 4.9 ks of Photon Counting (PC) mode data
between T0+44.9 ks and T0+68.8 ks.
No credible X-ray afterglow candidate has been detected within the
BAT-GUANO error circle (Tohuvavohu, GCN Circ. 32170) down to a 0.3 - 10
keV count-rate upper limit of ~ 2e-3 ct/s (3sigma c.l.).
The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/00021504.
Swift-UVOT began settled observations 45.1 ks after the trigger. No
optical afterglow consistent with the BAT-GUANO position is detected.
The 3.9 ks exposure in the white filter gives an upper limit of >21.9
mag.
This circular is an official product of the Swift team.
GCN Circular 32170
Subject
GRB 220606B: GUANO coordinate correction to GCN 32167
Date
2022-06-06T16:01:12Z (4 years ago)
From
Aaron Tohuvavohu at U Toronto <aaron.tohu@gmail.com>
The coordinates for GRB 220606B reported in GCN 32167 were transposed
in the declination, and therefore incorrect.
The correct coordinates of the GRB localization candidate are:
RA, Dec = 28.474, -54.741 deg which is
RA(J2000) = 01h 53m 53.76s
Dec(J2000) = -54d 44��� 27.6���
with an estimated uncertainty of 5 arcmin.
The Swift XRT/UVOT ToO followup is at the correct position.
Sincere apologies for the transcription error.
GCN Circular 32168
Subject
GRB 220606B: Swift ToO observations
Date
2022-06-06T13:32:22Z (4 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Swift/BAT-GUANO GRB 220606B.
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00021504
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Swift/BAT-GUANO event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a
GCN Circular after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
GCN Circular 32167
Subject
GRB 220606B: Swift/BAT-GUANO candidate arcminute localization of a short burst
Date
2022-06-06T12:23:36Z (4 years ago)
From
Aaron Tohuvavohu at U Toronto <aaron.tohu@gmail.com>
Aaron Tohuvavohu (U Toronto), James DeLaunay (UAlabama), Gayathri
Raman (PSU), Jamie A. Kennea (PSU), report:
Swift/BAT did not localize GRB 220606B onboard (T0:
2022-06-06T01:03:28 UTC, Fermi/GBM GCN 32165).
The Fermi notice, distributed in near real-time, triggered the Swift
Mission Operations Center operated Gamma-ray Urgent Archiver for Novel
Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).
Upon trigger by this notice, GUANO sent a command to the Swift Burst
Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from
[-50,+150] seconds around the time of the burst. All the requested
event mode data was delivered to the ground.
The BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu,
arXiv:2111.01769), detects the burst in a 0.512 s analysis time bin
with a sqrt(TS) of 10.7.
The duration of the burst as seen by BAT is less than 0.5 s.
A candidate arcminute localization is found with DeltaLLHOut of 11.3
and a DeltaLLHPeak of 3.1.
For this reason we can confidently claim detection, and preference for
an in FOV origin, but the best fit arcmin localization is not strongly
preferred over other positions.
See Section 9.1 and Figure 20 in the NITRATES paper for brief
descriptions and interpretations of sqrt(TS), DeltaLLHPeak, and
DeltaLLHOut.
The BAT position is
RA, Dec = 28.474, -54.471 deg which is
RA(J2000) = 01h 53m 53.76s
Dec(J2000) = -54d 28��� 15.6���
with an estimated uncertainty of 5 arcmin.
This position is consistent with the Fermi/GBM localization (GCN 32165).
XRT and UVOT follow-up has been requested.
Results of follow-up observations will be reported in future circulars.
GUANO is a fully autonomous, extremely low latency, spacecraft
commanding pipeline designed for targeted recovery of BAT event mode
data around the times of compelling astrophysical events to enable
more sensitive GRB searches.
A live reporting of Swift/BAT event data recovered by GUANO can be
found at: https://www.swift.psu.edu/guano/
GCN Circular 32166
Subject
Fermi GRB 220606B: Global MASTER-Net observations report
Date
2022-06-06T01:30:25Z (4 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko,
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin
(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
(Irkutsk State University, API),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),
A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov
(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) started inspect of the Fermi GRB 220606B ( Fermi GBM team, GCN 32165) errorbox 720 sec after notice time and 754 sec after trigger time at 2022-06-06 01:16:03 UT, with upper limit up to 19.3 mag. The observations began at zenith distance = 65 deg. The sun altitude is -53.7 deg.
The galactic latitude b = -66 deg., longitude l = 287 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1997640
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
785 | 2022-06-06 01:16:03 | MASTER-SAAO | (01h 27m 52.53s , -50d 19m 46.2s) | C | 60 | 19.0 |
875 | 2022-06-06 01:17:34 | MASTER-SAAO | (01h 40m 26.17s , -50d 17m 58.4s) | C | 60 | 19.2 |
957 | 2022-06-06 01:18:55 | MASTER-SAAO | (01h 24m 27.36s , -48d 24m 22.5s) | C | 60 | 19.3 |
1265 | 2022-06-06 01:24:03 | MASTER-SAAO | (01h 36m 29.45s , -48d 26m 09.1s) | C | 60 | 19.3 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 32165
Subject
GRB 220606B: Fermi GBM Final Real-time Localization
Date
2022-06-06T01:13:56Z (4 years ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
The Fermi GBM team reports the detection of a likely SHORT GRB
At 01:03:28 UT on 6 Jun 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220606B (trigger 676170213.675398 / 220606044).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 22.4, Dec = -50.0 (J2000 degrees, equivalent to J2000 01h 29m, -50d 00'), with a statistical uncertainty of 12.1 degrees.
The angle from the Fermi LAT boresight is 20.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220606044/quicklook/glg_skymap_all_bn220606044.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220606044/quicklook/glg_healpix_all_bn220606044.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220606044/quicklook/glg_lc_medres34_bn220606044.gif