GRB 220412A
GCN Circular 32326
Subject
GRB220412A: VIRT Optical Upper Limit
Date
2022-07-05T17:53:31Z (3 years ago)
From
Priyadarshini Gokuldass at U. of the Virgin Islands  <priyadass.94@gmail.com>
K. Noonan (UVI), P. Gokuldass (Florida Institute of Technology), N. Orange
(OrangeWave Innovative Science, LLC), K. Smith (UVI), D. Morris (UVI)
report:
We observed the field of GRB220412A (N. J. Klingler et al., GCN 31881) with
the 0.5m Virgin Island Robotic Telescope (VIRT) at the University of the
Virgin Islands' Etelman Observatory on 04-13-2022 starting at 00:11:58.73
UT (T+17.30 hrs). We performed a series of exposures in the R filter with a
total exposure of 4000 s. The weather conditions were partly cloudy during
the hours of observation with an average airmass of 1.25.
We find no new source within the enhanced XRT position error circle (P. A.
Evans et al., 31887) and report the following 5-sigma upper limit:
T_mid            ||Exposure     ||Filter      ||Limit
T+ 18.2 hrs    ||4000s          ||R            ||>20.8
The limit is estimated from comparison to nearby USNO B1 stars and is not
corrected for Galactic extinction. The VIRT is still in the commissioning
phase.
We acknowledge financial support from NASA MUREP MIRO award 80NSSC21M0001, NASA
EPSCoR award 80NSSC19M0060, and NSF EiR award 1901296.This message can be
cited.
GCN Circular 31903
Subject
GRB 220412A: GRANDMA observations
Date
2022-04-15T12:13:31Z (4 years ago)
From
Patrice Hello at LAL  <hello@lal.in2p3.fr>
Subject Line:
GRB 220412A: GRANDMA observations
Content:
S. Beradze (AbAO), U. Bhardwaj (GRAPPA), T. Culino (ESILV), P. Hello
(IJCLAB), M. Masek (FZU), G. Raaijmakers (GRAPPA), Y. Rajabov (UBAI),
T. Sadibekova (AIM/CEA-UPS), F. Z. Guo (THU), X. F. Wang (THU/BJP), Y.
Zhu (NAOC), J. Zhang (NAOC), D. A. Kann (HETH/IAA-CSIC), K. Noysena
(NARIT), A. Kaouech (OUCA/KNC) C. Rinner (OUCA), Z. Benkhaldoun (OUCA),
S. Antier (OCA/Artemis), P. A. Duverne (IJCLAB), M. Freeberg (KNC),
R. Hainich (UP), F. Runger (UP), S. Karpov (FZU), A. Simon (Kyiv Univ),
A. Baransky (Kyiv Univ) and V. Godunova (IC ICAMER)
report on behalf of GRANDMA collaboration:
The GRANDMA telescope network responded to the alert of GRB 220412A
(N. J. Klingler et al. GCNC 31881, P.A. Evans et al. GCN 31887,
A. D'Ai et al. GCN 31888, K.L. Page et al GCN 31890).
The first observations started ** h after the SWIFT BAT trigger time.
We did not detect the optical afterglow within the first 24 h.
Upper limits are given in the AB system, at 3-sigma.
T-T0(hr)| MJD������ | Observatory�� | Exposure| Filter | Upp. Lim. (AB)
_____________________________________________________
05.55 |59681.50689|Xinglong-2.16m|12*300s������ |�� R�������� |���� 19.5
14.02 |59681.86193|OST/CDK20�������� |18*180s������ |�� R�������� |���� 17.8
14.07 |59681.85977|OST/CDK20�������� |17*180s������ |�� I�������� |���� 17.0
17.36 |59681.99881|KNC-HAO������������ |5*180s�������� |�� L������ �� |���� 17.3
21.18 |59682.15807|TRT-SRO������������ |10*60s�������� |�� V ������ �� |���� 18.1
21.35 |59682.16537|TRT-SRO������������ |10*60s�������� |�� R ������ �� |���� 17.7
21.53 |59682.17271|TRT-SRO������������ |10*60s�������� |�� I ������ �� |���� 17.1
21.95 |59682.19014|KNC-T24������������ |3300s���������� |�� I ������ �� |���� 18.1
The observations were contaminated by the moon.
These upper limits are consistent with previous reports of detections by
RATIR (Alan M. Watson et al., GCN 31882 & GCN 31902) and the upper limits
provided by UVOT (A. Breeveld and N. Klingler, GCN 31885), MITSuME Akeno
(K. L. Murata et al., GCN 31891).
The Xinglong-2.16m and TRT-SRO data have been calibrated using nearby stars
from the Pan-STARRS catalog. The measurements for�� Xinglong-2.16m provided
by the STDPipe pipeline (Karpov 2022). The OST data have been using CDK
filter and calibrated with USNO-B1.0 Catalog (Monet+ 2003). The KNC-T24 and
KNC-HAO images have been calibrated using field stars from the 
PanSTARRS-DR1
catalog, measured with the MUPHOTEN pipeline (Duverne et al. 2021).
GRANDMA is a worldwide 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/).
GCN Circular 31902
Subject
GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
Date
2022-04-14T20:00:57Z (4 years ago)
From
Alan M Watson at UNAM  <alan@astro.unam.mx>
Alan M. Watson (UNAM), Nat Butler (ASU), Eleonora Troja (UTV), Alexander Kutyrev
(GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Enrico Ramirez-Ruiz (UCSC), Jes��s
Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey Moseley (GSFC), Rosa L.
Becerra (UNAM), Simone Dichiara (PSU), and Oc��lotl L��pez (UNAM) report:
We observed the field of GRB 220412A (Klingler et al. GCN 31881) with the
Reionization and Transients Infrared Camera (RATIR) on the 1.5m Harold Johnson
Telescope at the Observatorio Astron��mico Nacional on Sierra San Pedro M��rtir
from 2022-04-14 03:28 to 07:30 UTC (44.9 to 48.9 hours after the trigger)
obtaining 2.31 hours of exposure in the i band.
In comparison with the SDSS DR9 catalog, the afterglow candidate reported by
Watson et al. (GCN Circ. 31882, 31898) is detected at i = 21.51 +/- 0.10.
We note that the optical light curve appears to have steepened. The temporal
index between our observations at 21 hours (Watson et al., GCN Circ 31898) and
47 hours is close to -1.0.
Further observations are continuing.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro M��rtir.
GCN Circular 31901
Subject
GRB 220412A: BOOTES-network optical upper limits
Date
2022-04-14T00:05:31Z (4 years ago)
From
Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, T.-R. Sun, M. D. Caballero-Garcia, R. Sanchez-Ramirez (IAA-CSIC),  D. Hiriart and W. H. Lee (UNAM), C. Perez del Pulgar,  A. Castellon, I. Carrasco, A. Reina (Univ. de Malaga), I. H. Park (SKKU) and F. Rendon (IAA-CSIC and INTA-CEDEA) on behalf of a larger collaboration, report:
Following the detection of GRB 220412A by Swift (Klingler et al., GCNC 31881), the 0.3m BOOTES-1B robotic telescope in Mazagon (Huelva), southern Spain, automatically responded to this burst on Apr 12 at 22:41 UT (i.e. ~16.1 hours after trigger). In the co-added frame (52 x 60 s, clear filter), no source is detected within the enhanced XRT position (Evans et al., GCNC 31887) down to 19.2 mag.
Later on, the 60cm BOOTES-5/JGT robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) automatically responded to this burst on Apr 13 at 03:33 UT (i.e. ~ 21 hrs after trigger). In the co-added image (45 x 60 s, clear filter), no optical afterglow is detected within the enhanced XRT position (Evans et al., GCNC 31887) down to 20.3 mag.
Although the candidate reported by RATIR (Watson et al. GCNC 31882, GCNC 31898) is not detected, those non-detections are consistent with the reports from Swift/UVOT (Klingler et al., GCNC 31881, Breeveld et al. GCNC 31885), MITSuME (Murata et al. GCNC 31891) and MASTER-Net (Lipunov et al., GCNC 31880).
We thank the staff at INTA-CEDEA and San Pedro Martir Observatory for their excellent support.
GCN Circular 31899
Subject
GRB 220412A: Swift-BAT refined analysis
Date
2022-04-13T21:01:24Z (4 years ago)
From
Tyler Parsotan at UMBC/GSFC/CRESST II  <parsotat@umbc.edu>
T. Parsotan (GSFC/UMBC), S. D. Barthelmy (GSFC), 
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 220412A (trigger #1102281)
(Klingler et al. GCN Circ. 31881).  The BAT ground-calculated position is
RA, Dec = 123.975, 30.336 deg which is 
   RA(J2000)  =  08h 15m 54.0s 
   Dec(J2000) = +30d 20' 08.5" 
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 92%.
 
The BAT light curve showed a complex
structure with a duration of about 20 sec.  The peak count rate
was ~900 counts/sec (15-350 keV), at ~1 sec after the trigger.
T90 (15-350 keV) is 41.66 +- 7.00 sec (estimated error including systematics).
 
The time-averaged spectrum from T-11.07 to T+38.00 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.53 +- 0.21.  The fluence in the 15-150 keV band is 5.9 +- 0.9 x 10^-07 erg/cm2.
The 1-sec peak photon flux measured from T+6.88 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/1102281/BA/
GCN Circular 31898
Subject
GRB 220412A: RATIR Observations of the Fading Afterglow
Date
2022-04-13T20:05:34Z (4 years ago)
From
Alan M Watson at UNAM  <alan@astro.unam.mx>
Alan M. Watson (UNAM), Nat Butler (ASU), Eleonora Troja (UTV), Alexander
Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox
(STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Enrico Ramirez-Ruiz
(UCSC), Jes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey Moseley
(GSFC), Rosa L. Becerra (UNAM), Simone Dichiara (PSU), and Oc��lotl L��pez (UNAM)
report:
We observed the field of GRB 220412A (Klingler et al. GCN 31881