GRB 200529A
GCN Circular 27844
Subject
GRB 200529A: Fermi GBM Final Real-time Localization
Date
2020-05-29T01:06:53Z (5 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 LONG GRB
At 00:56:39 UT on 29 May 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200529A (trigger 612406604.278114 / 200529039).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 239.2, Dec = -18.1 (J2000 degrees, equivalent to J2000 15h 56m, -18d 06'), with a statistical uncertainty of 8.5 degrees.
The angle from the Fermi LAT boresight is 83.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200529039/quicklook/glg_skymap_all_bn200529039.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200529039/quicklook/glg_healpix_all_bn200529039.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200529039/quicklook/glg_lc_medres34_bn200529039.gif
GCN Circular 27845
Subject
GRB 200529A: Swift detection of a burst
Date
2020-05-29T01:13:29Z (5 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
V. D'Elia (SSDC), E. Ambrosi (INAF-IASFPA), A. D'Ai (INAF-IASFPA),
J.D. Gropp (PSU), J. A. Kennea (PSU), N. J. Klingler (PSU),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC/CRESST), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU), D. M. Palmer (LANL),
A. Tohuvavohu (U Toronto) and T. N. Ukwatta (LANL) report on behalf of
the Neil Gehrels Swift Observatory Team:
At 00:56:35 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200529A (trigger=974942). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 238.751, -11.057 which is
RA(J2000) = 15h 55m 00s
Dec(J2000) = -11d 03' 25"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a weak pulse
with a duration of about 30 sec. The peak count rate
was ~1700 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 01:00:08.7 UT, 212.9 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 238.76571, -11.07215 which is
equivalent to:
RA(J2000) = 15h 55m 03.77s
Dec(J2000) = -11d 04' 19.7"
with an uncertainty of 5.2 arcseconds (radius, 90% containment). This
location is 75 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. No
spectrum from the promptly downlinked event data is yet available to
determine the column density.
UVOT took a finding chart exposure of 144 seconds with the White filter
starting 216 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 56% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 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 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.29.
Burst Advocate for this burst is V. D'Elia (delia AT ssdc.asi.it).
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 27846
Subject
GRB 200529A: NOT optical afterglow
Date
2020-05-29T01:39:44Z (5 years ago)
From
Daniele B Malesani at DTU Space <malesani@space.dtu.dk>
Daniele B. Malesani (DTU Space), Tapio Pursimo (NOT), Charles L.
Steinhardt (DAWN/NBI), report:
We observed the field of GRB 200529A (D'Elia et al., GCN 27845) using
the Nordic Optical Telescope equipped with the ALFOSC camera.
In a single 300-s image, starting on May 29.052 UT (18.9 min after the
GRB), we detect a bright point source just outside the currently
available XRT position, which is not visible in the archival Pan-STARRS
images of the same field. We measure for this object the following
position (J2000):
RA = 15:55:03.21
Dec = -11:04:26.2
By comparison with nearby stars from the Pan-STARRS catalog, we measure
a magnitude r = 20.00 +- 0.02.
We conclude that this object is the optical afterglow of GRB 200529A.
GCN Circular 27847
Subject
GRB 200529A: KAIT Optical Afterglow Confirmation
Date
2020-05-29T06:56:59Z (5 years ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, observed the field of GRB 200529A (GBM detection:
GCN 27844; Swift detection: D'Elia et al., GCN 27845), starting at
~5.25 hours after the burst. We obtained 23x60s images in the clear
(roughly R) filter. We marginally detect, therefore confirm the
optical afterglow reported by Malesani et al. (GCN 27846) in our
co-added image. We estimate the afterglow to be 21.2 +/- 0.2 magnitude
in clear filter, calibrated to PS1 catalog.
GCN Circular 27848
Subject
GRB 200529A: Enhanced Swift-XRT position
Date
2020-05-29T06:59:54Z (5 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester)
report on behalf of the Swift-XRT team.
Using 1535 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 200529A, 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 = 238.76394, -11.07363 which is equivalent
to:
RA (J2000): 15h 55m 3.34s
Dec (J2000): -11d 04' 25.1"
with an uncertainty of 1.8 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 27853
Subject
GRB 200529A: BOOTES-2/TELMA early optical upper limit
Date
2020-05-29T10:54:37Z (5 years ago)
From
Youdong HU at IAA-CSIC <youdong@iaa.es>
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado (IAA-CSIC), C. Perez
del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga), R.
Fernandez-Munoz (IHSM/UMA-CSIC), M.D. Caballero-Garcia and M. Jelinek
(ASU-CAS), on behalf of a larger collaboration, report:
The 60cm BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC)
in Algarrobo Costa (Malaga, Spain) automatically responded to GRB
200529A as detected by Swift (D'Elia et al GCNC 27845). No new source is
seen in the initial 10s exposure gathered at 00:58:28 UT(~ 113 s after
the burst onset) down to a 18.0 limiting magnitude. Further images (20 x
10s) were combined to produce a deeper image down to 18.8 mag limit at
median time of 10.5 min post burst. No early-time bright optical
emission is detected at the NOT (Malesani et al. GCNC 27846) and KAIT
(Zheng et al. GCNC 27847) reported optical afterglow.
We thank the staff at La Mayora for its excellent support.
GCN Circular 27858
Subject
GRB 200529A: LCO Optical Afterglow Detection
Date
2020-05-29T13:24:48Z (5 years ago)
From
Robert Strausbaugh at U. of the Virgin Islands <robert.strausbaugh@uvi.edu>
R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:
We observed Swift GRB 200529A (D'Elia et al., GCN 27845) with the LCO 1-m Sinistro instrument at the Siding Spring Observatory, Australia site, on May 29, from 10:05 to 10:28 UT (corresponding to 9.15 to 9.53 hours from the GRB trigger time) with the Bessel R and I filters.
We performed a series of 5x120s exposures in R and I. We clearly detect an optical source in R band, and force a detection in I band with less than one sigma significance, in stacked images at a location consistent with other optical afterglow detections (Malesani et al., GCN 27846; Zheng et al., GCN 27847). Using the USNO-B.1 catalog as reference, we calculate the following magnitudes:
R = 21.76 +/- 0.18
I = 22.82 +/- 1.06
These magnitudes are not corrected for galactic extinction.
R.S. is funded by NSF AST grant #1831682
GCN Circular 27859
Subject
GRB 200529A: Fermi GBM Detection
Date
2020-05-29T16:50:37Z (5 years ago)
From
Oliver J Roberts at USRA/NASA <oliver.roberts@nasa.gov>
O.J. Roberts (USRA) and C. Meegan (UAH) report on behalf of
the Fermi GBM Team:
"At 00:56:39.28 UT on May 29th 2020, the Fermi
Gamma-Ray Burst Monitor (GBM) triggered and located
GRB 200529A (trigger 612406604 / 200529039) which was
also detected by the Swift (V. D'Elia et al. 2020, GCN 27845).
The Fermi GBM Final Real-time Localization (GCN 27844)
is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time
is 77 degrees.
The GBM light curve shows multiple peaks with a duration
(T90) of about 85 s (50-300 keV). The time-averaged spectrum
from T0-3.5 s to T0+81.5 s is best fit by a power law function
with an exponential high-energy cutoff.
The power law index is -1.34 (+0.16/-0.15) and the cutoff
energy, parameterized as Epeak, is 73.99 (+11.10/-8.18) keV.
The event fluence (10-1000 keV) in this time interval is
(4.08 +/- 0.27)E-06 erg/cm^2. The 1-sec peak photon flux
Measured starting from T0+17.8 s in the 10-1000 keV band
is 2.7 +/- 0.2 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 27863
Subject
GRB 200529A: Swift-XRT refined Analysis
Date
2020-05-30T01:13:03Z (5 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A. D'Ai (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp (PSU), J.A.
Kennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester),
P.A. Evans (U. Leicester), A. Melandri (INAF-OAB) and V. D'Elia report
on behalf of the Swift-XRT team:
We have analysed 3.7 ks of XRT data for GRB 200529A (D'Elia et al. GCN
Circ. 27845), from 197 s to 44.3 ks after the BAT trigger. The data
comprise 51 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Goad et al.
(GCN Circ. 27848).
The light curve can be modelled with an initial power-law decay with an
index of alpha=4.0 (+/-0.6), followed by a break at T+580 s to an alpha
of 0.44 (+0.19, -0.17).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.29 (+0.29, -0.20). The
best-fitting absorption column is consistent with the Galactic value
of 2.4 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 2.8 x 10^-11 (4.5 x 10^-11) erg cm^-2 count^-1.
A summary of the WT-mode spectrum is thus:
Total column: 2.4 (+/-0.8) x 10^21 cm^-2
Galactic foreground: 2.4 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index: 2.29 (+0.29, -0.20)
If the light curve continues to decay with a power-law decay index of
0.44, the count rate at T+24 hours will be 0.013 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.7 x
10^-13 (5.9 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00974942.
This circular is an official product of the Swift-XRT team.
GCN Circular 27868
Subject
GRB 200529A: Swift-BAT refined analysis
Date
2020-05-30T14:22:59Z (5 years ago)
From
Sibasish Laha at GSFC <sibasish.laha@nasa.gov>
H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), V. D'Elia (SSDC),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
Using the data set from T-61 to T+242 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 200529A (trigger #974942)
(V. D'Elia, et al., GCN Circ. 27845). The BAT ground-calculated position is
RA, Dec = 238.756, -11.076 deg which is
RA(J2000) = 15h 55m 01.3s
Dec(J2000) = -11d 04' 34.5"
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%.
The mask weighted light curve shows a complex structure. The
overall structure starts at ~T-5 s and lasts till ~T+100 s.
T90 (15-350 keV) is 79.57 +- 7.26 sec (estimated error including systematics).
The time-averaged spectrum from T-1.24 to T+92.92 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.89 +- 0.10. The fluence in the 15-150 keV band is 3.2 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.58 sec in the 15-150 keV band
is 1.8 +- 0.3 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/974942/BA/
GCN Circular 27878
Subject
GRB 200529A: MITSuME Akeno optical upper limits
Date
2020-06-01T06:45:39Z (5 years ago)
From
Ogawa Futa at Tokyo Institute of Technology <ogawa@hp.phys.titech.ac.jp>
F. Ogawa, R. Adachi, R. Hosokawa, M. Niwano, K. L. Murata, N.
Nakamura, Y. Yatsu, and N. Kawai(TokyoTech) report on behalf of the
MITSuME collaboration:
We observed the field of GRB 200529A (Fermi GBM team, GCN #27844;
D'Elia et al. GCN #27845) 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 started on 10:25:35 UT. The first 47 images were
heavily affected by the bad weather at Akeno Observatory. We did not
detect the optical afterglow (Daniele et al., GCN #27846; WeiKang et
al., GCN #27847; Strausbaugh et al., GCN #27858) in the stacked image.
We obtained the 5-sigma limits as follows.
T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
10.3 11:35:06 1140 g'>17.3, Rc>17.1, Ic>16.5
------------------------------------------------------------------------------------------------
T0+: Elapsed time after the burst
T-EXP: Total Exposure time
We used UCAC4 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., submitted;
https://github.com/MNiwano/Eclair)
GCN Circular 27884
Subject
GRB 200529A: Swift/UVOT Upper Limits
Date
2020-06-03T01:43:27Z (5 years ago)
From
Kira Simpson at PSU <kira.simpson1984@gmail.com>
GRB 200529A: Swift/UVOT Upper Limits
K. K. Simpson (PSU) and V. D'Elia (SSDC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 200529A
195 s after the BAT trigger (D'Elia et al., GCN Circ. 27845).
No optical afterglow consistent with the optical position
(Malesani et al. GCN Circ. 27846)
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 216 360 142 >19.8
white 216 360 142 >19.8
v 195 3771 209 >19.1
b 4392 4495 102 >19.5
u 4187 4386 197 >19.7
w1 3982 4182 197 >19.0
m2 3777 3977 197 >20.2
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.29 in the direction of the burst
(Schlegel et al. 1998).