GRB 221028A
GCN Circular 32874
Subject
GRB 221028A: Swift detection of a burst
Date
2022-10-28T13:32:46Z (3 years ago)
From
Jamie Kennea at Penn State U <jak51@psu.edu>
A. Y. Lien (U Tampa), E. Ambrosi (INAF-IASFPA), A. D'Ai (INAF-IASFPA),
V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU),
P. A. Evans (U Leicester), R. A. J. Eyles-Ferris (U Leicester),
J.D. Gropp (PSU), J. A. Kennea (PSU), S. Laha (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
K. L. Page (U Leicester), D. M. Palmer (LANL),
T. M. Parsotan (GSFC/UMBC/CRESSTII), B. Sbarufatti (INAF-OAB),
M. H. Siegel (PSU) and M. A. Williams (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:
At 13:16:27 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 221028A (trigger=1131910). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 314.206, +41.066 which is
RA(J2000) = 20h 56m 49s
Dec(J2000) = +41d 03' 56"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a multi-peaked
structure with a duration of about 40 sec. The peak count rate
was ~2300 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 13:18:03.7 UT, 96.1 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 314.20310,
41.08996 which is equivalent to:
RA(J2000) = 20h 56m 48.74s
Dec(J2000) = +41d 05' 23.9"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 86 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.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (7.76 x
10^21 cm^-2, Willingale et al. 2013), with an excess column of 2.3
(+2.57/-1.47) x 10^22 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 8.64e-10 erg cm^-2 s^-1 (0.2-10
keV).
UVOT data is unavailable at this time.
Burst Advocate for this burst is A. Y. Lien (yarleen AT gmail.com).
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 32876
Subject
GRB 221028A: GIT optical upper limit
Date
2022-10-28T15:26:09Z (3 years ago)
From
Harsh Kumar at Indian Inst of Tech,Bombay <harshkosli13@gmail.com>
H. Kumar (IITB), G. Waratkar, V. Swain (IITB), Anirban Dutta (IIA), G. C.
Anupama(IIA), K. Angail (IAO), V. Bhalerao (IITB), S. Barway (IIA) report
on behalf of the GIT team:
We observed GRB 221028A detected by Swift (A. Y. Lien et al. GCN # 32874)
with 0.7m GROWTH-India Telescope (GIT). We obtained two 300-sec exposures
in the r' filter. We did not detect any new source within a 5-arcsec radius
uncertainty circle around the Swift-XRT position (A. Y. Lien et al. GCN #
32874) in our stacked image. The upper limit follows as:
-------------------------------------------------------------------
JD (mid) | T_mid-T0(hrs) | Filter | Lim_Mag (5-sigma) |
-------------------------------------------------------------------
2459881.102968 | 1.2 | r' | > 20.24 |
-------------------------------------------------------------------
The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016)
and not corrected for Galactic extinction.
The GROWTH India Telescope (GIT; Kumar et al. 2022
<https://iopscience.iop.org/article/10.3847/1538-3881/ac7bea>) is a 70-cm
telescope with a 0.7-degree field of view, set up by the Indian Institute
of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB)
with funding from DST-SERB and IUSSTF. It is located at the Indian
Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding
by the IITB alumni batch of 1994, which partially supports the operations
of the telescope. Telescope technical details are available at
https://sites.google.com/view/growthindia/.
GCN Circular 32878
Subject
GRB 221028A: BOOTES-4/MET optical upper limit
Date
2022-10-28T16:03:30Z (3 years ago)
From
Youdong HU at IAA-CSIC <huyoudong072@hotmail.com>
Y.-D. Hu, E. Fernandez-Garcia, I. Perez-Garcia, A. J. Castro-Tirado, M. D. Caballero-Garcia, R. Sanchez-Ramirez (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 221028A by Swift (Lien et al. GCNC 32874), the 0.6m BOOTES-4/MET robotic telescope at Lijiang Astronomical Observatory (China) automatically responded to this burst starting on Oct. 28 at 13:24:22 UT (~8 min after trigger). No new source is detected within the XRT error region (Lien et al. GCNC 32874) in the co-added image (33 x 10 s, clear filter) down to 19.9 mag, which is consistent with the non-detection reported by GIT (Kumar et al., GCNC 32876).
We thank the staff at Lijiang observatory for their excellent support.
GCN Circular 32879
Subject
Swift GRB 221028A: Global MASTER-Net observations report
Date
2022-10-28T18:16:35Z (3 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) was pointed to the Swift GRB 221028A ( A. Y. Lien et al., GCN 32874) errorbox 17090 sec after notice time and 17113 sec after trigger time at 2022-10-28 18:01:41 UT, with upper limit up to 18.7 mag. Observations started at twilight. The observations began at zenith distance = 74 deg. The sun altitude is -13.0 deg.
The galactic latitude b = -3 deg., longitude l = 83 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=2137317
We obtain a following upper limits.
Tmid-T0 | Site |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________
17203 | MASTER-SAAO | C | 180 | 18.4 |
17414 | MASTER-SAAO | C | 180 | 18.7 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 32881
Subject
GRB 221028A: LCOGT Optical Upper Limits
Date
2022-10-28T20:43:59Z (3 years ago)
From
Robert Strausbaugh at University of Minnesota <rstrausb@umn.edu>
R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on
behalf of a larger collaboration:
We observed the GRB 221028A (Lien et al., GCN 32874) field with the LCOGT
1-meter Sinistro instrument at the Teide Observatory, on Tenerife, on
October 28, from 19:17 to 19:44 (corresponding to 6.02 to 6.45 hours from
the GRB trigger time) with the SDSS r and i filters.
We performed a series of 3x300s exposures in each band. We do not detect
any uncatalouged sources in the XRT error region, in either band,
consistent with other optical upper limits (Kumar et al., GCN 32876; Hu et
al., GCN 32878; Lipunov et al., GCN 32879).
The following upper limits are calculated using the Pan-STARRS catalog as
reference:
r > 21.80
i > 21.62
These magnitudes are not corrected for galactic extinction.
GCN Circular 32883
Subject
GRB 221028A: MITSuME Okayama optical upper limits
Date
2022-10-29T07:02:15Z (3 years ago)
From
Masafumi Niwano at Tokyo Institute of Tech <niwano@hp.phys.titech.ac.jp>
M. Niwano, R. Hosokawa, I.Takahashi, K. L. Murata, Y. Imai, N. Ito, S.
Sato, N. Higuchi, M. Tateda, M. Sasada, Y. Yatsu, and N. Kawai (Tokyo
Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 221028A (A. Y. Lien et al. GCN Circular
#32874, H. Kumar et al. GCN Circular #32876, Y.-D. Hu et al. GCN
Circular #32878, V. Lipunov et al. GCN Circular #32879, R. Strausbaugh
et al. GCN Circular #32881) with the optical three color (g', Rc, and
Ic) CCD cameras attached to the MITSuME 50 cm telescope Okayama.
The observation with a series of 60 sec exposures started at 2022-10-28
13:17:23 UT (59 seconds after the Swift/BAT trigger). We stacked the
images with good conditions. We did not detect any uncatalogued sources
within the Swift/XRT error region (A. Y. Lien et al. GCN Circular
#32874). We obtained the 5-sigma limits of the stacked images as follows.
T0+[sec] | MID-UT | T-EXP[sec] | 5-sigma limits
------------------------------------------------------------------------------------------------
59 | 2022-10-28 14:17:10 | 5790.0 | g'>18.7, Rc>19.5, Ic>18.7
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used 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 32885
Subject
GRB 221028A: AGILE detection
Date
2022-10-29T08:43:27Z (3 years ago)
From
Alessandro Ursi at INAF/IAPS <alessandro.ursi@gmail.com>
A. Ursi, F. Longo (Univ. Trieste and INFN Trieste), C. Pittori, F.
Verrecchia (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor
Vergata), A. Argan, M. Cardillo, C. Casentini, Y. Evangelista, L. Foffano,
E. Menegoni, G. Piano (INAF/IAPS), A. Bulgarelli, A. Di Piano, V. Fioretti,
G. Panebianco, N. Parmiggiani (INAF/OAS-Bologna), F. Lucarelli (SSDC, and
INAF/OAR), M. Romani (INAF/OA-Brera), M. Marisaldi (INAF/OAS-Bologna, and
Bergen University), M. Pilia, A. Trois (INAF/OA-Cagliari), I. Donnarumma
(ASI), A. Giuliani (INAF/IASF-Mi), and P. Tempesta (TeleSpazio), report on
behalf of the AGILE Team:
The AGILE satellite detected the GRB 221028A at T0 = 2022-10-28 13:16:27 s
(UTC), reported by Swift BAT (GCN #32874). The burst is clearly visible in
the AGILE scientific ratemeters of the MiniCALorimeter (MCAL; 0.4-100 MeV)
and AntiCoincidence (AC; 50-200 keV) detectors. The event lasted about 2 s
and it released a total number of 3155 counts in the MCAL detector (above a
background rate of 1180 Hz), and 7270 counts in the AC detector (above a
background rate of 3410 Hz). The AGILE ratemeters light curves can be found
at http://www.agilescienceapp.it/notices/GRB221028A_AGILE_RM.png .
The event also triggered a high time resolution MCAL data acquisition, from
T0-4.31 s to T0+33.35 s (UTC), and released 1924 counts in the detector,
above a background rate of 477 Hz. The MCAL light curve can be found at
http://www.agilescienceapp.it/notices/GRB221028A_080686_594047787.000000.png
. The time-integrated spectrum of the burst between T0-2s and T0+7s be
fitted in the energy range 0.4-10 MeV with a power-law with ph. ind. =
-2.65 (-0.39/+0.50), resulting in a reduced chi-squared of 0.78 (48 d.o.f.)
and a fluence of 3.1e-06 ergs/cm^2 (90% confidence level), in the same
energy range. At the T0, the event was 49 deg off-axis.
Additional analysis of AGILE data is in progress. Automatic MCAL GRB alert
Notices can be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html.
GCN Circular 32886
Subject
GRB 221028A: HCT optical upper limit
Date
2022-10-29T08:49:36Z (3 years ago)
From
Harsh Kumar at Indian Inst of Tech,Bombay <harshkosli13@gmail.com>
H. Kumar (IITB), A. Dutta (IIA), D.K. Sahu (IIA), G. C. Anupama (IIA), S.
Barway (IIA), V. Bhalerao (IITB), R. Gupta (ARIES), K. Misra (ARIES), D.
Panchal (ARIES), S.B. Pandey (ARIES), report on behalf of the HCT team:
We observed GRB 221028A detected by Swift-BAT (A. Y. Lien et al. GCN #
32874) with the 2.0m Himalayan Chandra Telescope (HCT) of the Indian
Astronomical Observatory (IAO). We obtained exposures in the Bessel V, Rc
and Ic filters and did not detect any afterglow within the Swift-XRT
uncertainty circle (A. Y. Lien et al. GCN # 32874). The obtained upper
limits follow as:
-------------------------------------------------------------------
JD (mid) | T_mid-T0(hrs) | Exposure (sec) | Filter | Lim_mag (5-sigma) |
-------------------------------------------------------------------
2459881.075085 | 0.52 | 60 | Rc | > 19.94 |
2459881.091424 | 0.92 | 300 | Rc | > 22.06 |
2459881.1037215| 1.21 | 300 | Ic | > 20.74 |
2459881.108775 | 1.33 | 420 | V | > 22.30 |
-------------------------------------------------------------------
The upper limits are consistent with Kumar et al., GCN #32876; Hu et al.,
GCN #32878; Lipunov et al., GCN #32879, R. Strausbaugh et al., GCN #32881.
The reported magnitudes are in the AB system of magnitude, calibrated
against PanSTARRS DR1 (Chambers et al., 2016) using Lupton's transformation
equations available at
http://classic.sdss.org/dr4/algorithms/sdssUBVRITransform.html#Lupton2005
and not corrected for Galactic extinction.
These observations were carried out under the ToO program HCT-2022-C3-P12.
We thank the HCT staff for their support during the observations. The
Indian Astronomical Observatory is operated by the Indian Institute of
Astrophysics, Bengaluru, India.
GCN Circular 32888
Subject
GRB 221028A: COATLI Upper Limits
Date
2022-10-29T17:43:28Z (3 years ago)
From
Alan M Watson at UNAM <alan@astro.unam.mx>
Alan M. Watson (UNAM), Nat Butler (ASU), Rosa Becerra (UNAM), Simone
Dichiara (PSU), Tzveti Dimitrova (ASU), Oc��lotl L��pez (UNAM), Diego
Gonz��lez (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Margarita
Pereyra (UNAM), Eleonora Troja (UTV/ASU) and report:
We observed the field of the GRB 221028A (Lien et al., GCN Circ. 32874)
with the COATLI 50-cm telescope and HUITZI f/8 imager at the Observatorio
Astron��mico Nacional on the Sierra de San Pedro M��rtir (
http://coatli.astroscu.unam.mx) from 2022-10-29 02:13 UTC to 08:03 UTC
(13.5 to 19.3 hours after the trigger), obtaining a total of 244 minutes of
exposure in the r filter.
At the position of the XRT afterglow (Lien et al., GCN Circ. 32874), we do
not detect a source to the following 3-sigma upper limit:
r > 23.4
Our photometry is calibrated against the Pan-STARRS1 catalog, is on an
approximate AB system, and is not corrected for Galactic extinction in the
direction of the GRB.
We thank the COATLI/HUITZI technical team and the staff of the Observatorio
Astron��mico Nacional.
GCN Circular 32889
Subject
GRB 221028A: CrAO/ZTSh optical upper limit
Date
2022-10-29T20:04:27Z (3 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), N. Pankov (HSE), V. Rumyantsev (CrAO), A. Pozanenko
(IKI) report on behalf of IKI GRB FuN:
We observed the GRB 221028A (Lien et al., GCN 32874; Ursi et al., GCN
32885) with ZTSh 2.6m telescope of CrAO observatory starting on Oct. 28
(UT) 19:38:37. We do not detect any optical object within XRT
localization (Lien et al., GCN 32874). This is consistent with reported
non-detections (Hu et al., GCN 32878; Kumar et al., GCN 32876;
Lipunov et al., GCN 32879; Strausbaugh et al., GCN 32881; Niwano et al.,
GCN 32883; Kumar et al., GCN 32886; Watson et al., GCN 32888).
Preliminary photometry of the field in a combined image is following
Date UT start t-T0 Filter Exp. OT err UL(3sigma)
(mid, days) (s)
2022-10-28 19:38:37 0.27233 R 10*120 n/d n/d 20.7
The photometry is based on several nearby USNO-B1.0 (R2) stars
USNO-B1.0
RA DEC R2
20:56:40.7621 +41:04:57.000 15.60
20:56:51.9768 +41:04:22.922 17.21
20:57:00.0629 +41:02:55.072 16.04
GCN Circular 32893
Subject
GRB 221028A, Swift-BAT refined analysis
Date
2022-10-30T16:04:53Z (3 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 221028A (trigger #1131910)
(Lien et al., GCN Circ. 32874). The BAT ground-calculated position is
RA, Dec = 314.198, 41.082 deg which is
RA(J2000) = 20h 56m 47.5s
Dec(J2000) = +41d 04' 56.0"
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 53%.
The mask-weighted light curve shows a short pulse that starts and peaks
at ~T0 and ends at ~T+2, followed by several overlapping pulses that lasts
till ~T+84 s. The structure resembles those of short GRBs with extended
emission.
T90 (15-350 keV) is 57.1 +- 15.0 sec (estimated error including
systematics).
Due to current detector issues, data below ~50 keV are inaccurate. Thus,
only data above 50 keV are used for spectral analysis. The time-averaged
spectrum from T-0.1 to T+84.0 sec is best fit by a simple power-law model.
The power law index of the time-averaged spectrum is 1.367 +- 0.325.
The fluence in the 15-150 keV band is 1.51 +- 0.14 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.56 sec in the 15-150 keV band
is 0.8 +- 0.2 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/1131910/BA/
GCN Circular 32894
Subject
GRB 221028A: AKO Optical Upper Limit
Date
2022-10-30T20:24:14Z (3 years ago)
From
Mohammad Odeh at Al Khatim Observatory M44 <mshodeh@gmail.com>
Mohammad Odeh at Al-Khatim Astronomical Observatory (AKO), operated by the
International Astronomical Center (IAC), in Abu Dhabi, the United Arab
Emirates.
We observed the GRB 221028A (Lien et al., GCN 32874) with our 0.36m
telescope on 30 October from 15:39 to 16:44 (UT). We obtained exposures in
the B, V, and Ic filters and did not detect any afterglow within XRT
localization (Lien et al., GCN 32874). This is consistent with the reported
non-detections of (Hu et al., GCN 32878; Lipunov et al., GCN 32879;
Strausbaugh et al., GCN 32881; Niwano et al., GCN 32883; Kumar et al., GCN
32886; Watson et al., GCN 32888; Belkin et al., GCN 32889).
Each image consists of seven stacked frames, each frame is a 3-minute
exposure. The obtained upper limits are as follows:
Mid Time (UT), Filter, Lim. Mag.
2022-10-30T16:16:06Z, B, > 18.3
2022-10-30T16:13:03Z, V, > 19.6
2022-10-30T16:09:22Z, Ic, > 20.2
GCN Circular 32895
Subject
GRB 221028A: Correction to GCN 32893 - Fluence and flux are for 50-150 keV
Date
2022-10-31T01:55:30Z (3 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
The fluence for the time averaged spectrum and the 1-s peak
flux quoted in the BAT refined analysis for GRB 221028A
(Palmer et al., GCN Circ. #32893) should be for the energy
range of 50-150 keV, instead of the 15-150 keV written in
the original circular.
In other words, it should be
"The fluence in the 50-150 keV band is 1.51 +- 0.14 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.56 sec in the 50-150 keV band
is 0.8 +- 0.2 ph/cm2/sec."
We apologize for the typos and any confusion this may cause.
GCN Circular 32896
Subject
GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
Date
2022-10-31T02:35:10Z (3 years ago)
From
Toktarkhan Komesh at Nazarbayev University <toktarkhan.komesh@nu.edu.kz>
T. Komesh (NU), B. Grossan (UCB, NU), Z. Maksut (NU), M. Krugov (FAI),
report on behalf of the Energetic Cosmos Laboratory: The Nazarbayev
University Transient Telescope at Assy-Turgen Astrophysical Observatory
(NUTTelA-TAO) observed the field of GRB 221028A on receipt of an
automated GCN / BAT position alert, observing in Sloan g', r' and i'
bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan,
Kumar & Smoot 2019, JHEA, 32, 14).We started observations at UT
2022-10-28 13:47:19, 1852 s after the BAT trigger. Observations were
made under partially cloudy conditions, beginning with the target at an
altitude of 82 deg. No new or changing sources consistent with the XRT
position (Lien 2022, GCN 32874) were detected. Note that these
observations provide essentially full-time coverage, simultaneous in all
three bands. We report the following results: start time t-t0(s) end
time UL g' UL r' ULi' exposure_time (s) ------------ --------
----------- ------ ------ ----- ------ 13:47:19 1852 13:48:19 19.3 18.9
18.7 60 13:48:19 1912 13:58:19 20.3 19.4 20.0 600 start time is in UT.
t-t0(s) gives the time since trigger, in seconds. UL gives the 5 sigma
upper limit sensitivity in magnitudes for an image withindividual
exposure time (first row) and for images co-added to the given exposure
time (second row).��The given upper limit values are derived from the
average calibration with only 2-4 standard stars per co-added frame, and
no other analysis or corrections. ---------------------------------- NU
= Nazarbayev University, Nur-Sultan, Kazakhstan UCB = University of
California, Berkeley, USA FAI = Fesenkov Astrophysical Institute,
Kazakhstan This research has been funded by the Science Committee of the
Ministry of Science and Higher Education of the Republic of Kazakhstan
(Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of
the staff of the Assy-Turgen Astrophysical Observatory, Almaty,
Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazkhstan.
GCN Circular 32897
Subject
GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
Date
2022-10-31T02:47:47Z (3 years ago)
From
Toktarkhan Komesh at Nazarbayev University <toktarkhan.komesh@nu.edu.kz>
T. Komesh (NU), B. Grossan (UCB, NU), Z. Maksut (NU), M. Krugov (FAI), report on behalf of the Energetic Cosmos Laboratory:
The Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) observed the field of GRB 221028A on receipt of an automated GCN / BAT position alert, observing in Sloan g', r' and i' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14).
We started observations at UT 2022-10-28 13:47:19, 1852 s after the BAT trigger. Observations were made under partially cloudy conditions, beginning with the target at an altitude of 82 deg. No new or changing sources consistent with the XRT position (Lien 2022, GCN 32874) were detected. Note that these observations provide essentially full-time coverage, simultaneous in all three bands. We report the following results:
start time t-t0(s) end time UL g' UL r' ULi' exposure_time (s)
------------ -------- ----------- ------ ------ ----- ------
13:47:19 1852 13:48:19 19.3 18.9 18.7 60
13:48:19 1912 13:58:19 20.3 19.4 20.0 600
start time is in UT. t-t0(s) gives the time since trigger, in seconds. UL gives the 5 sigma upper limit sensitivity in magnitudes for an image with individual exposure time (first row) and for images co-added to the given exposure time (second row).��The given upper limit values are derived from the average calibration with only 2-4 standard stars per co-added frame, and no other analysis or corrections.
----------------------------------
NU = Nazarbayev University, Nur-Sultan, Kazakhstan
UCB = University of California, Berkeley, USA
FAI = Fesenkov Astrophysical Institute, Kazakhstan
This research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of the staff of the Assy-Turgen Astrophysical Observatory, Almaty, Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazkhstan.
GCN Circular 32898
Subject
GRB 221028A: 1.3m DFOT Optical upper limit
Date
2022-10-31T07:20:02Z (3 years ago)
From
Amit Kumar Ror at ARIES <mitturor77894@gmail.com>
Amit Kumar Ror, Snehlata, Rahul Gupta, S. B. Pandey, Amar Aryan, Ankur
Ghosh, Dimple, and Kuntal Misra (ARIES) report:
We observed Swift-BAT detected GRB 221028A (Lien et al. GCN 32874) using
the 2Kx2K CCD Imager mounted on the 1.3m Devasthal Fast Optical Telescope
(DFOT) located at the Devasthal observatory of Aryabhatta Research
Institute of Observational Sciences (ARIES), India. The observations were
started on 2022-10-28 at 15:17:46, i.e., around 2 hours after the BAT
trigger. We have taken multiple frames, each having an exposure time of 300
sec in the R filter. We did not detect any new source within the XRT error
circle in our stacked image. We obtain the following 3-sigma upper limit in
the stacked image.
Date Start (UT) T_start-T0 (hours) Filter Exp time (sec) Limiting
magnitude
===============================================================
2022-10-28 15:17:46 ~2 R 300x6 > 21.5
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 catalog.
The non-detection of the optical afterglow is consistent with Kumar et al.
GCNs 32876, 32886; Hu et al. GCN 32878; Lipunov et al. GCN 32879;
Strausbaugh et al. GCN 32881; Niwano et al. GCN 32883; Watson et al. GCN
no. 32888; Belkin et al. GCN 32889; Odeh GCN 32894; and Komesh et al. GCN
32897.
This circular may be cited.
GCN Circular 32899
Subject
GRB 221028A: Swift-XRT refined Analysis
Date
2022-10-31T07:29:01Z (3 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
V. D'Elia (SSDC & INAF-OAR), D.N. Burrows (PSU), J. D. Gropp (PSU), S.
Dichiara (PSU), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester),
K.L. Page (U. Leicester), B. Sbarufatti (INAF-OAB), A. D'Ai
(INAF-IASFPA) and A.Y. Lien report on behalf of the Swift-XRT team:
We have analysed 5.6 ks of XRT data for GRB 221028A (Lien et al. GCN
Circ. 32874), from 92 s to 28.1 ks after the BAT trigger. The data
comprise 23 s in Windowed Timing (WT) mode (the first 2 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The refined XRT position is RA, Dec = 314.2027, +41.0898 which is
equivalent to:
RA (J2000): 20 56 48.64
Dec(J2000): +41 05 23.3
with an uncertainty of 3.5 arcsec (radius, 90% confidence).
The light curve can be modelled with a power-law decay with a decay
index of alpha=2.04 (+0.13, -0.12).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.5 (+0.5, -0.4). The
best-fitting absorption column is 2.4 (+1.0, -0.8) x 10^22 cm^-2, in
excess of the Galactic value of 7.8 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 8.2 x 10^-11 (1.3 x 10^-10) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 2.4 (+1.0, -0.8) x 10^22 cm^-2
Galactic foreground: 7.8 x 10^21 cm^-2
Excess significance: 3.3 sigma
Photon index: 1.5 (+0.5, -0.4)
If the light curve continues to decay with a power-law decay index of
2.04, the count rate at T+24 hours will be 8.3 x 10^-6 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.8 x
10^-16 (1.1 x 10^-15) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01131910.
This circular is an official product of the Swift-XRT team.
GCN Circular 32904
Subject
GRB 221028A: Detection by VZLUSAT-2
Date
2022-11-01T18:05:11Z (3 years ago)
From
Jakub Ripa at Masaryk University <245487@mail.muni.cz>
J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),�� N. Werner (Masaryk
U.), M. Ohno (Hiroshima U.),�� L. Meszaros, B. Csak (Konkoly
Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F.
Hroch, M. Dafcikova, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec,
J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo
(Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida
(ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K.
Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe
(Rikkyo U.), L. L. Kiss (Konkoly Observatory),�� T. Mizuno (Hiroshima
U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe
(Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes
(VZLU), I. Vertat (FEL ZCU)�� -- the VZLUSAT-2/GRB payload collaboration.
A long-duration GRB 221028A (Swift/BAT detection: Lien et al., GCN Circ.
32874; AGILE detection: Ursi et al., GCN Circ. 32885; KONUS-Wind
detection: trig. time 2022-10-28 13:16:29.550 UT; INTEGRAL/SPI-ACS
detection peak at 2022-10-28 13:16:28.3 UT) was detected by both GRB
detector units on board of the VZLUSAT-2 3U CubeSat
(https://www.vzlusat2.cz/en/).
The data acquisition was performed by GRB detector units no. 0 and no.
1. The 7.1 (6.1) sigma detection significance was confirmed at detector
unit no. 0 (no. 1) at 2022-10-28 13:16:26 UTC. The T90 duration was
measured to be 23 s (26 s) for detector unit no. 0 (no. 1).
The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB221028A_GCN_VZLUSAT2.pdf
GRB detectors on VZLUSAT-2 are a demonstration payload for a future
CubeSats constellation (Werner et al. Proc. SPIE 2018). Two GRB modules
of VZLUSAT-2 are placed in a perpendicular manner and each consists of a
75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the
energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022
January 13 from Cape Canaveral.
GCN Circular 32906
Subject
GRB 221028A: GRANDMA observations
Date
2022-11-03T14:55:19Z (3 years ago)
From
Alexander Kann at IAA-CSIC <kann@iaa.es>
N. Kochiashvili (AbAO), Z. Vidadi (ShAO), D. A. Kann (Goethe Univ.),
P. Gokuldass (Florida Tech.), S. Beradze (AbAO), Sh. Aghayeva (ShAO),
R. Le Montagner (IJCLab), C. Rinner, Z. Benkhaldoun (OUCA), A.Janati
(HAO), S. Antier (OCA/Artemis), J. Ali, A. Kaeouach (KNC), and Sergey
Karpov (FZU) report on behalf of the GRANDMA collaboration:
The GRANDMA telescope network responded to the Swift-BAT alert of
GRB 221028A (Lien et al., GCN 32874, Palmer et al., GCN 32893,
D'Elia et al., GCN 32899), which was also detected by AGILE (Ursi
et al., GCN 32885) and VZLUSAT-2 (Ripa et al., GCN 32904).
The first observations started 5.43 hours after the BAT trigger time.
The optical counterpart of the afterglow was not detected in our
observations.
In the following table we report the preliminary photometry of our
observations. Upper limits are reported at the 5-sigma limit,
in the AB system.
T-T0 (hr)| MJD | Obser. |Exposure | Filter| Upp.Lim. (AB)
--------------------------------------------------------------------
5.4341 |59880.77951| MOSS | 60 x 60 s | Clear | 21.5
5.8778 |59880.79591| KNC-HAO | 47 x 180 s | L | 22.0
MOSS data has been calibrated with the Gaia DR2 catalog.
HAO data has been calibrated with PS1 catalog.
Values are not corrected for the very large Galactic extinction
E(B-V) = 1.8573 mag (Schlafly & Finkbeiner 2011).
Our upper limits are in agreement with other non-detections from
Swift UVOT (Lien et al., GCN 32874), GIT (Kumar et al., GCN 32876),
BOOTES-4/MET (Hu et al., GCN 32878), MASTER (Lipunov et al., GCN 32879),
LCOGT (Strausbaugh et al., GCN 32881), MITSuME (Niwano et al., GCN
32883),
HCT (Kumar et al., GCN 32886), COATLI (Watson et al., GCN 32888),
ZTSh 2.6m (Belkin et al., GCN 32889), AKO (Odeh et al., GCN 32894),
NUTTelA-TAO/BSTI (Komesh et al., GCN 32896, 32897), and DFOT (Kumar et
al., GCN 32898).
GRANDMA is a worldwide coordinated telescope network
(grandma.ijclab.in2p3.fr) devoted to the observation of transients
in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS
497, 5518). Kilonova-Catcher (KNC) is the citizen science program of
GRANDMA (http://kilonovacatcher.in2p3.fr/).