GRB 140318A
GCN Circular 15986
Subject
GRB 140318A: Swift detection of a burst
Date
2014-03-18T00:35:21Z (11 years ago)
From
Jamie A. Kennea at PSU/Swift-XRT <kennea@swift.psu.edu>
S. B. Cenko (GSFC), M. G. Bernardini (INAF-OAB), D. N. Burrows (PSU),
P. D'Avanzo (INAF-OAB), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU),
F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), T. Sakamoto (AGU),
B. Sbarufatti (INAF-OAB/PSU) and M. H. Siegel (PSU) report on behalf
of the Swift Team:
At 00:09:07 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 140318A (trigger=592204). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 184.053, +20.207 which is
RA(J2000) = 12h 16m 13s
Dec(J2000) = +20d 12' 27"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a single peak
structure with a duration of about 30 sec. The peak count rate
was ~1320 counts/sec (15-350 keV), at ~5 sec after the trigger.
The XRT began observing the field at 00:11:12.7 UT, 124.8 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 184.0906, 20.2080 which is equivalent to:
RA(J2000) = +12h 16m 21.74s
Dec(J2000) = +20d 12' 28.8"
with an uncertainty of 6.9 arcseconds (radius, 90% containment). This
location is 127 arcseconds from the BAT onboard position, within the
BAT error circle. No event data are yet available to determine the
column density using X-ray spectroscopy.
The initial flux in the 2.5 s image was 3.63e-10 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 132 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. Results from the 2.7'x2.7' sub-image
are not available at this time. 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 0.02.
Burst Advocate for this burst is S. B. Cenko (brad.cenko 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/too.html.)
GCN Circular 15987
Subject
GRB 140318A: NOT detection of the afterglow
Date
2014-03-18T02:04:47Z (11 years ago)
From
Steve Schulze at U of Iceland <sts30@hi.is>
S. Schulze (PUC and MCSS), T. Kruehler (ESO Chile), N. R. Tanvir (U Leicester), A. A. Djupvik (NOT), and P. Jakobsson (U Iceland) report on behalf of a larger collaboration:
We observed the field of GRB 140318A (Cenko et al., GCN 15986) with 2.5m the Nordic Optical Telescope (NOT) equipped with StanCAM. We obtained 3 x 300 s in the R band. Observations started at 00:52:00 UT on March 18 (i.e. 43 min after the burst).
We detect a bright point source at the position
R.A.(J2000) = 12:16:21.40
Dec. (J2000) = +20:12:31.9
We measure R = 19.7 +/- 0.1 mag at 45 min after the trigger. The object coincides with a faint galaxy in the SDSS catalog which we identify as the putative host galaxy. SDSS J121621.38+201232.1 has a r'-band magnitude of 22.87 +/-0.26 mag(AB) and a photometric redshift of 0.42 +/- 0.02.
GCN Circular 15988
Subject
GRB 140318A: WHT spectroscopy
Date
2014-03-18T04:25:02Z (11 years ago)
From
Nial Tanvir at U.Leicester <nrt3@star.le.ac.uk>
N. R. Tanvir (U. Leicester), T. Kruehler (ESO Chile),
S. Schulze (PUC and MCSS), R. Karjalainen (ING) report:
We observed the afterglow of GRB 140318A (Cenko et al. GCN 15986;
Schulze et al. GCN 15987) with the WHT using the ACAM spectrograph,
beginning March 18 02:06 UT, approximately 2 hours post-trigger.
The wavelength range covered was from about 5000 AA to 9500 AA.
In our provisional reduction, the continuum trace of the
aftergow+host is well detected, and a single emission line is seen
at ~7520 AA. It is most likely that this is OII 3727, given the
absence of any other lines. We therefore infer a redshift of
z=1.02, and tentatively identify this as the redshift of the burst.
Further analysis is ongoing.
GCN Circular 15989
Subject
GRB140318A: Discovery Channel Telescope Optical Detection
Date
2014-03-18T06:55:48Z (11 years ago)
From
John Capone at UMD <jicapone@astro.umd.edu>
J. Capone (UMD), E. Troja (NASA-GSFC), V. Toy (UMD), S.B. Cenko
(NASA-GSFC), A. Kutyrev (NASA-GSFC), A. Cucchiara (NASA-GSFC), S. Veilleux
(UMD), and S. Gezari (UMD) report on behalf of a larger collaboration:
We observed the field of GRB140318A (Cenko et al., GCN 15986) with the
Large Monolithic Imager (LMI) on the recently commissioned 4.3m Discovery
Channel Telescope (DCT) at Happy Jack, AZ. We started a sequence of r', i'
and z' images beginning at 2014-03-18 03:32 UTC (approximately 3.5 hours
after the Swift trigger).
A source is clearly detected in all filters at the location of the optical
afterglow (Schulze et al, GCN 15987). Using nearby point sources from SDSS
for calibration, we measure preliminary magnitudes of r' = 21.6 +/- 0.2, i'
= 21.14 +/- 0.06 and z' = 20.86 +/- 0.04 at an average time of ~5 hours
after the GRB. These values are not corrected for Galactic extinction in
the direction of the GRB.
The source shows evidence of fading when compared with the NOT observation,
confirming that this is the optical afterglow.
Additional multi-band observations are ongoing.
We thank the staff of the Discovery Channel Telescope for assistance with
these observations.
GCN Circular 15990
Subject
GRB 140318A: RATIR Optical and NIR Detections
Date
2014-03-18T08:32:11Z (11 years ago)
Edited On
2024-11-07T18:53:30Z (7 months ago)
From
Owen Littlejohns at Az State U <olittlej@asu.edu>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
Owen Littlejohns (ASU), Nat Butler (ASU), Alan M. Watson (UNAM),
Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G.
Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB), J. Xavier
Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (ORAU/GSFC),
Eleonora Troja (GSFC), Enrico Ramirez-Ruiz (UCSC), José A. de Diego
(UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos
Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC)
report:
We observed the field of GRB 140318A (Cenko, et al., GCN 15986) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org)
on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico
Nacional on Sierra San Pedro Mártir from 2014/03 18.15 to 2014/03 18.31
UTC (3.36 to 7.40 hours after the BAT trigger) obtaining a total of 0.99
hours exposure in the r and i bands and 0.60 hours exposure in the Z, Y,
J, and H bands.
We detect the previously reported optical counterpart (Schulze, et al. GCN
15987). In comparison with the SDSS DR9 and 2MASS, we obtain the following
detections:
r 21.88 +/- 0.33
i 21.37 +/- 0.18
Z 20.67 +/- 0.20
Y 20.76 +/- 0.29
J 20.60 +/- 0.21
H 20.29 +/- 0.19
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. In comparison to the observations
of Schulze, et al. (GCN 15987) the measured r-band magnitude is consistent
with a power-law decay with a temporal index alpha = -1.0.
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.
GCN Circular 15991
Subject
GRB 140318A: Enhanced Swift-XRT position
Date
2014-03-18T08:51:12Z (11 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 2346 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 140318A, 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 = 184.08924, +20.20902 which is equivalent
to:
RA (J2000): 12h 16m 21.42s
Dec (J2000): +20d 12' 32.5"
with an uncertainty of 1.9 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 15992
Subject
GRB 140318A: Liverpool Telescope optical observations
Date
2014-03-18T09:01:24Z (11 years ago)
From
Andrea Melandri at INAF-OAB <andrea.melandri@brera.inaf.it>
A. Melandri (INAF-OAB), C. Guidorzi (U. Ferrara), A. Gomboc (U. Ljubljana), I. A. Steele and C. G. Mundell (LJMU), on behalf of a large collaboration report:
The 2-m Liverpool Telescope robotically followed up Swift GRB 140318A (Cenko et al., GCN 15986) at 00:27:37 UT (~18.5 min after the burst trigger).
We clearly detect the optical afterglow at the position reported by Schulze et al. (GCN 15987). In a coadded 6x10s SDSS-r image, we estimate the magnitude r' = 19.84 +- 0.11 at t_mid = 50.6 min since the Swift/BAT trigger time. The magnitude is calibrated against nearby SDSS stars.
GCN Circular 15993
Subject
GRB 140318A: Swift-XRT refined Analysis
Date
2014-03-18T19:35:04Z (11 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
C. Pagani (U. Leicester), A. Melandri (INAF-OAB), B. Sbarufatti
(INAF-OAB/PSU), P. D'Avanzo (INAF-OAB), V. Mangano (PSU), M.C. Stroh
(PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester), P.A. Evans
(U. Leicester) and S.B. Cenko report on behalf of the Swift-XRT team:
We have analysed 6.7 ks of XRT data for GRB 140318A (Cenko et al. GCN
Circ. 15986), from 114 s to 46.2 ks after the BAT trigger. The data
comprise 219 s in Windowed Timing (WT) mode (the first 9 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. 15991).
The light curve can be modelled with an initial power-law decay with an
index of alpha=0.48 (+/-0.20), followed by a break at T+263 s to an
alpha of 1.88 (+0.07, -0.06).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.21 (+0.12, -0.11). The
best-fitting absorption column is 1.14 (+0.27, -0.25) x 10^21 cm^-2,
in excess of the Galactic value of 2.6 x 10^20 cm^-2 (Kalberla et al.
2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum is 2.9 x 10^-11 (3.9 x 10^-11) erg
cm^-2 count^-1.
A summary of the WT-mode spectrum is thus:
Total column: 1.14 (+0.27, -0.25) x 10^21 cm^-2
Galactic foreground: 2.6 x 10^20 cm^-2
Excess significance: 5.8 sigma
Photon index: 2.21 (+0.12, -0.11)
If the light curve continues to decay with a power-law decay index of
1.88, the count rate at T+24 hours will be 2.1 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.2 x
10^-15 (8.3 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/00592204.
This circular is an official product of the Swift-XRT team.
GCN Circular 15996
Subject
GRB 140318A: Swift-BAT refined analysis
Date
2014-03-18T23:58:07Z (11 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
S. B. Cenko (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC),
T. N. Ukwatta (MSU) (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 140318A (trigger #592204)
(Cenko, et al., GCN Circ. 15986). The BAT ground-calculated position is
RA, Dec = 184.049, 20.225 deg which is
RA(J2000) = 12h 16m 11.8s
Dec(J2000) = +20d 13' 30.8"
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 49%.
The mask-weighted light curve shows a main single pulse starts at ~T+2 s and
ends at ~T+12 s, with some weak extented emissions starting before the main pulse
at ~T-20 s and extended after the pulse to ~T+50 s. T90 (15-350 keV) is 8.43 +- 1.27 sec
(estimated error including systematics).
The time-averaged spectrum from T+2.24 to T+11.68 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.35 +- 0.28. The fluence in the 15-150 keV band is 2.9 +- 0.5 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+5.48 sec in the 15-150 keV band
is 0.5 +- 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/592204/BA/
GCN Circular 15997
Subject
GRB 140318A: Swift/UVOT Upper Limits
Date
2014-03-19T14:07:38Z (11 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@swift.psu.edu>
B. Porterfield (PSU) and Cenko (GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 140318A
132 s after the BAT trigger (Cenko et al., GCN Circ. 15986).
No optical afterglow consistent with the XRT position
(Cenko et al. GCN Circ. 15986) or NOT position (Schulze et al., GCN
Circ 15987) 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 132 282 147 >21.2
white 132 5340 541 >21.9
v 4115 5750 393 >19.6
b 3499 5135 393 >20.9
u 4730 4930 197 >20.1
w1 4525 6063 298 >20.5
m2 4320 5955 393 >21.2
w2 3910 5546 393 >20.7
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 15998
Subject
GRB 140318A: Mondy optical limit
Date
2014-03-19T15:00:05Z (11 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A.Volnova (IKI), E. Klunko (ISTP), I. Korobtsev (ISTP), M. Eselevich
(ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up
collaboration:
We observed the field of GRB 140318A (Cenko et al., GCN 15986) with
AZT-33IK telescope of Mondy observatory starting on Mar. 18 (UT)
13:18:36. Within enhanced Swift-XRT eror circle (Goad et al., GCN 15991)
we do not detect the optical afterglow (Schulze et al., GCN 15987).
Details of preliminary photometry is following:
date UT start t-T0 Exp. Filter UpperLimit (3sigma)
(mid, days) (s)
2014-03-18 13:18:36 0.59896 58x120 R 21.1
The photometry is based on reference star SDSS-DR9, (R mag,
transformation by Lupton 2005):
N SDSS_id R(Lupton) err
J121613.64+200907.3 16.984 0.008
GCN Circular 15999
Subject
GRB 140318A: Continued RATIR Optical and NIR Observations
Date
2014-03-19T21:38:45Z (11 years ago)
Edited On
2024-11-07T19:36:59Z (7 months ago)
From
Owen Littlejohns at Az State U <olittlej@asu.edu>
Edited By
Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
Owen Littlejohns (ASU), Nat Butler (ASU), Alan M. Watson (UNAM),
Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer
(UNAM), Chris Klein (UCB), Ori Fox (UCB), J. Xavier Prochaska
(UCSC), Josh Bloom (UCB), Antonino Cucchiara (ORAU/GSFC), Eleonora
Troja (GSFC), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM),
Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga
(UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report:
We observed the field of GRB 140318A (Cenko, et al., GCN 15986) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org)
on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico
Nacional on Sierra San Pedro Mártir from 2014/03 19.13 to 2014/03 19.50
UTC (26.91 to 35.94 hours after the BAT trigger), obtaining a total of
4.88 hours exposure in the r and i bands and 2.46 hours exposure in the
Z and Y bands.
We continue to detect the previously reported optical counterpart
(Littlejohns, et al., GCN 15990; Schulze, et al., GCN 15987). In
comparison with the SDSS DR9 and 2MASS, we obtain the following detections:
r 22.52 +/- 0.11
i 22.05 +/- 0.09
Z 21.58 +/- 0.12
Y 21.51 +/- 0.16
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. Fading of the source is detected
for all of the four bands measured in both epochs of RATIR observations.
We note that the temporal decay index between these two epochs appears to
be shallower than that reported in Littlejohns, et al. (GCN 15990), with
-0.5 < alpha < -0.3 for all four bands. This can be interpretted as the
magnitude approaching that of the underlying SDSS galaxy reported in
Schulze, et al. (GCN 15987).
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.