GRB 141028A
GCN Circular 17035
Subject
GRB 141028A: Mondy optical observations
Date
2014-11-07T08:08:50Z (12 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Volnova (IKI), E. Klunko (ISTP), M. Eselevich (ISTP),
I. Korobtsev (ISTP), A. Pozanenko (IKI) report on behalf of larger GRB
follow-up collaboration:
We observed the field of GRB 141028A (Bissaldi et al., GCN 16969) with
AZT-33IK telescope of Sayan observatory (Mondy) on Oct., 30 starting on
(UT) 14:12:40. We obtained several images in R-filter. In a combined image
we detect optical afterglow (Gorbovskoy et al., GCN 16972; Graham et al.,
GCN 16977).
Details of the photometry are following:
date UT start t-T0 Filter Exp. OT OT_err
(mid, days) (s)
2014-10-30 14:12:40 2.1733 R 2520 21.66 0.22
The photometry is based on following SDSS DR9 stars:
SDSS_id R_Lupton
J213021,99-001255,7 15.503
J213030,76-001427,8 17.205
J213035,56-001205,6 16.620
GCN Circular 17030
Subject
GRB 141028A: TShAO optical observation
Date
2014-11-05T20:23:23Z (12 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Volnova (IKI), A. Khruslov (INASAN), A. Kusakin
(Fesenkov Astrophysical Institute), A. Pozanenko (IKI) report on behalf
of larger GRB follow-up collaboration:
We observed the field of GRB 141028A (Bissaldi et al., GCN 16969)
with Zeiss-1000 (East) 1-m telescope of Tien Shan Astronomical
Observatory on Oct., 29 starting on (UT) 15:58:47. We obtained several
images in R-filter. In a combined image we clearly detect optical
afterglow (Gorbovskoy et al., GCN 16972; Graham et al., GCN 16977).
Details of the photometry are following:
date UT start t-T0 Filter Exp. OT OT_err
(mid, days) (s)
2014-10-29 15:58:47 1.2300 R 10*300 20.5 0.10
The photometry is based on following SDSS DR9 stars:
SDSS_id R_Lupton
J213021,99-001255,7 15.503
J213030,76-001427,8 17.205
J213035,56-001205,6 16.620
GCN Circular 16993
Subject
GRB 141028A: SAO RAS Zeiss-1000 photometry
Date
2014-10-30T17:32:39Z (12 years ago)
From
Vladimir Sokolov at SAO RAS <sokolov@sao.ru>
A.S. Moskvitin, V.N. Komarova, T.N. Sokolova and O.I. Spiridonova
SAO RAS) report on behalf of the GRB follow-up team:
We observed the field of GRB 141028A (Bissaldi et al., GCN 16969)
with the SAO RAS 1-m telescope Zeiss-1000 on October, 29. The observations
were started at 18:09:57 UT, ended at 19:40:42. We obtained 14 x 300 sec.
images in the Rc filter.
The OT discovered by the MASTER team (Gorbovskoy et al., GCN 16972)
and observed by numerous telescopes is clearly detected in our stacked
frame. The magnitude of OT is R = 20.6 +/- 0.1 in 8 hours since the Fermi
trigger (in Vega system, not corrected for the Milky Way extinction). The
photometry is based on the nearby USNO-B1 stars and checked with the other
catalogues.
On the occasion of the twenty-fifth anniversary of the Zeiss-1000 telescope
we would like to thank our colleagues S.V. Drabek, V.V. Komarov,
V.S. Shergin and V.V. Vlasyuk who have modernized the telescope control
system and provided its reliable operation.
GCN Circular 16991
Subject
GRB 141028A: Continued RATIR Observations
Date
2014-10-30T16:13:49Z (12 years ago)
From
Eleonora Troja at GSFC <eleonora.troja@nasa.gov>
Eleonora Troja (GSFC), 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), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), Jos�� A. de Diego (UNAM), Leonid Georgiev (UNAM),
Jes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Neil Gehrels (GSFC),
and Harvey Moseley (GSFC) report:
We observed the field of GRB 141028A (Bissaldi, et al., GCN 16969) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astron��mico Nacional on
Sierra San Pedro M��rtir from 2014/10 30.08 to 2014/10 30.31 UTC (39.07
to 44.46 hours after the GBM trigger), obtaining a total of 4.24 hours
exposure in the r, i, and z bands.
For a source within the enhanced XRT error circle (Pagani et al., GCN
16986),
in comparison with the SDSS DR9, we obtain the following detections:
r 21.19 �� 0.04
i 20.79 �� 0.03
z 20.74 �� 0.24
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. A comparison to our previous
observations (Troja et al., GCN 16980) shows that the afterglow faded
with a
power-law decay index of alpha ~ 0.9 in all three filters, consistent
with the decay
reported by Cenko & Perley (GCN 16989).
Further observations are planned.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 16990
Subject
GRB 141028A: Swift/UVOT followup observations
Date
2014-10-30T13:21:38Z (12 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. Breeveld (MSSL/UCL) and C. Pagani (U. Leicester) report on behalf of
the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 141028A
31037 s after the LAT trigger (Bissaldi et al., GCN Circ. 16969).
A fading source is detected in the initial exposures (Siegel and
Pagani, GCN Circ., 16979) in the position given in that circular, also
consistent with MASTER (Gorbovsky et a., GCN, Circ 16972), GROND (Graham
et al., GCN Circ. 16977) and the XRT (Pagani, et al., GCN Circ 16986).
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial
exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 31037 31179 140 19.0+-0.18
u 69790 72355 2525 20.7+-0.13
u 105469 127705 4880 21.3+-0.18
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.05 in the direction of the
burst (Schlegel et al. 1998).
GCN Circular 16989
Subject
GRB 141028A: P60 Observations and Decay Index
Date
2014-10-30T03:42:40Z (12 years ago)
From
S. Bradley Cenko at NASA/GSFC <brad.cenko@nasa.gov>
S. B. Cenko (NASA/GSFC) and D. A. Perley (Caltech) report on behalf of a larger collaboration:
We have imaged the location of the optical afterglow (Gorbovskoy et al., GCN 16972) of the Fermi GBM (Roberts et al., GCN 16971) and LAT (Bissaldi et al., GCN 16969) GRB141028A with the robotic Palomar 60 inch telescope. Using nearby point sources from the Sloan Digital Sky Survey for reference, we measure the following r'-band magnitudes in our P60 images:
r' = 20.09 +/- 0.06 at dt = 15.8 hr after the burst
r' = 21.00 +/- 0.05 at dt = 39.3 hr after the burst
Based on these observations, we infer a power-law decay index of alpha ~ 0.9.
GCN Circular 16986
Subject
GRB 141028A: Swift-XRT observations
Date
2014-10-29T16:39:33Z (12 years ago)
From
Claudio Pagani at U of Leicester <cp232@star.le.ac.uk>
C. Pagani, K. L. Page and P. A. Evans (U. Leicester) report on behalf
of the Swift-XRT team:
We have analysed 3.0 ks of XRT data for the Fermi/LAT-detected burst:
GRB 141028A, from 31.0 ks to 71.7 ks after the Fermi/LAT trigger. The
data are entirely in Photon Counting (PC) mode. An X-ray source is
detected within the Fermi/LAT error circle. Using 348 s of PC mode data
and 1 UVOT images, we find an enhanced XRT position (using the XRT-UVOT
alignment and matching UVOT field sources to the USNO-B1 catalogue):
RA, Dec = 322.60168, -0.23145 which is equivalent to:
RA (J2000): 21h 30m 24.40s
Dec(J2000): -00d 13' 53.2"
with an uncertainty of 4.0 arcsec (radius, 90% confidence). This
position is 367 arcsec from the Fermi/LAT position (Bissaldi et al. GCN
16969) and consistent with the positions of the optical counterpart
detected by MASTER (Gorbovskoy et al. GCN 16972), GROND (Graham et al.
GCN 16977) and UVOT (Siegel et al. GCN 16979).
The light curve can be modelled with a power-law decay with a decay
index of alpha=2.0 (+/-1.0).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.5 (+/-0.5). The
best-fitting absorption column is 1.8 (+2.2, -1.3) x 10^21 cm^-2, in
excess of the Galactic value of 4.1 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum is 3.0 x 10^-11 (5.0 x 10^-11) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 1.8 (+2.2, -1.3) x 10^21 cm^-2
Galactic foreground: 4.1 x 10^20 cm^-2
Excess significance: 1.8 sigma
Photon index: 2.5 (+/-0.5)
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020420.
This circular is an official product of the Swift-XRT team.
GCN Circular 16985
Subject
GRB 141028A: LCOGTN observations
Date
2014-10-29T11:39:20Z (12 years ago)
From
Drejc Kopac at Math Phys U,Slovenia <drejc.kopac@fmf.uni-lj.si>
D. Kopac (LJMU), J. Japelj (U. Ljubljana), C. Guidorzi (U. Ferrara), C.
Mundell (LJMU), S. Dichiara (U. Ferrara), on behalf of a large
collaboration report:
Using the Las Cumbres Observatory Global Telescope Network (LCOGTN) we
observed the field of Fermi GRB 141028A (Bissaldi et al., GCN 16969;
Roberts, GCN 16971). Optical observations in r' and i' filters (5 x 120s
sequences) were obtained with 1-m telescopes in Sutherland (South
Africa) and Cerro Tololo (Chile).
At the position of the MASTER telescope detection (Gorbovskoy et al.,
GCN 16972) we detect an un-catalogued source, consistent with GROND
(Graham et al., 16977), UVOT (Siegel et al., GCN 16979) and RATIR
detections (Troja et al., GCN 16980). Our preliminary photometry yields:
Mid time from Total Exp Filter Magnitude
trigger (hr) (s)
-------------------------------------------------
10.2 600 r' 19.4 +- 0.1
10.6 960 i' 19.3 +- 0.2
14.9 600 i' 19.9 +- 0.2
------------------------------------------------
The magnitudes are calibrated against nearby SDSS stars and are not
corrected for the Galactic foreground extinction. Further observations
with the LCOGTN are scheduled.
GCN Circular 16983
Subject
GRB 141028A: VLT/X-shooter redshift of z=2.33
Date
2014-10-29T08:15:25Z (12 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
D. Xu (DARK/NBI), A. J. Levan (Univ. Warwick), J. P. U. Fynbo
(DARK/NBI), N. R. Tanvir (Univ. Leicester), V. D'Elia (ASI/ASDC and
INAF/Roma), D. Malesani (DARK/NBI), report on behalf of a larger
collaboration:
We observed the optical afterglow (Gorbovskoy et al., GCN 16972; Graham
et al., GCN 16977) of the Fermi/LAT GRB 141028A (Roberts, GCN 16971;
Bissaldi et al., GCN 16969; Hurley et al., GCN 16975), using the
X-shooter spectrograph at the ESO VLT. Observations started at 02:15 UT
on 2014 Oct 29 (15.35 hr after the GRB), and consisted of 4x600 s
exposures in each of the UVB, VIS, and NIR arms, covering the wavelength
range 3000-25,000 AA.
We detect a variety of absorption features throughout the entire
spectrum. In particular, a wide trough is visible centered around 4050
AA, which we interpret as due to H I absorption at redshift z = 2.33.
Identification of several metal features as due to, among others, Si II,
C II, Fe II, C IV, Mg II, allows us to refine the value to z = 2.332.
We note the presence of a strong intervening system at z = 1.823
(detected e.g. in C IV, Fe II, Mg II), and a weaker one at z = 2.09 (C
IV). The former coincides with the system reported by Cucchiara et al.
(GCN 16982).
We acknowledge excellent support from the ESO observing staff at
Paranal, in particular Cedric Ledoux and Dimitri Gadotti.
GCN Circular 16982
Subject
GRB141028A: Gemini-North redshift
Date
2014-10-29T06:04:43Z (12 years ago)
From
Antonino Cucchiara at NASA/GSFC <antonino.cucchiara@nasa.gov>
A. Cucchiara (NASA/GSFC) reports on behalf of a larger collaboration:
We obtained a spectrum of the afterglow (Kennea et al., GCN 16978, Gorbovskoy et al.
GCN 16972, Graham et al. GCN 16977, Siegel et al. GCN 16979) of the Fermi GRB 141028A
(Bissaldi et al., GCN 16969, Roberts et al. GCN 16971) with the Gemini Multi-Object
Spectrograph mounted on the 8 m Gemini-North telescope.
Observations began at 05:07 UT on 2014 October 29 (~18. hr after the Fermi-GBM trigger)
and cover the wavelength range from 3800-8200 A. We acquired 2x600s exposure
using the R400 grism.
We detect several absorption lines, including CrII2056,ZnII2056, FeII2260, FeII2344,
FeII2586, FeII2600, MgII2706, MgII2803, and MgI 2853 at the common redshift of z=1.82.
We therefore suggest this to be the redshift of GRB 141028A.
We thank the Gemini-North staff for their terrific support, in particular
A. Petric and A. Smith.
GCN Circular 16980
Subject
GRB 141028A: RATIR Optical and NIR Observations
Date
2014-10-29T04:12:02Z (12 years ago)
Edited On
2024-11-07T18:49:34Z (2 years ago)
From
Eleonora Troja at GSFC <eleonora.troja@nasa.gov>
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>
Eleonora Troja (GSFC), Antonino Cucchiara (ORAU/GSFC), 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), Owen
Littlejohns (ASU),
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 the Fermi/LAT GRB 141028A (Bissaldi et al., GCN
16969, Roberts et al.
GCN 16971) with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org <http://www.ratir.org/>) on the
1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional
on Sierra San Pedro
Mártir from 2014/10 29.08 to 2014/10 29.13 UTC (from 13.62 to 14.82
hours after the
Fermi-GBM trigger), obtaining a total of 1.07 hours exposure in the r,
i and z bands.
At the position of the XRT and optical counterparts (Kennea et al., GCN
16978, Gorbovskoy
et al. GCN 16972, Graham et al. GCN 16977), in comparison with the SDSS
DR9, we
obtain the following detections:
r 20.09 +/- 0.02
i 19.85 +/- 0.02
z 19.50 +/- 0.10
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.
[GCN OPS NOTE(29oct14)" Per author's request, the Subject-line was
corrected from "29A" to "28A".]
GCN Circular 16979
Subject
GRB 141028A: Swift/UVOT Detection
Date
2014-10-29T03:58:53Z (12 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@swift.psu.edu>
M. H. Siegel (PSU) and C. Pagani (UL) report on behalf of the
Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 141028A
31037 s after the LAT trigger (Bissaldi et al., GCN Circ. 16969).
We detect an optical afterglow consistent with the afterglow reported by
MASTER (Gorbovsky et a., GCN, Circ 16972), GROND (Graham et al., GCN Circ.
16977) and the XRT (Kennea, et al., GCN Circ 16978).
The preliminary UVOT position is:
RA (J2000) = 21:30:24.54 = 322.60226 (deg.)
Dec (J2000) = -00:13:52.4 = -0.23122 (deg.)
with an estimated uncertainty of 0.4 arc sec. (radius, 90% confidence). This is
consistent with the GROND and MASTER positions.
Preliminary detection using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposure is:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 31037 37759 233 19.14+-0.19
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 16978
Subject
GRB 141028A: Swift/XRT detection of the X-ray afterglow
Date
2014-10-29T02:14:36Z (12 years ago)
From
Jamie A. Kennea at PSU/Swift-XRT <kennea@swift.psu.edu>
J. A. Kennea (PSU), J. L. Racusin (NASA/GSFC) and C. Pagani (UL) report on
behalf of the Swift Team:
Swift-XRT has observed the error circle of the Fermi/LAT GRB 141028A in a
series of observations tiled on the sky. The total exposure time is 2.0 ks
spread over 7 fields; the maximum exposure within the sky observed was 766
s. The observations started 31.0 ks after the Fermi/LAT trigger. Within
these data we detect a bright, uncatalogued X-ray source at RA, Dec=
322.60078, -0.23116 which is equivalent to:
RA (J2000.0) = 21h 30m 24.19s
Dec (J2000.0) = -00d 13' 52.2"
with an uncertainty of 5.8 arcsec (radius, 90% confidence). The exposure
at this location was 277 s. We note that this source is 4.8 arcsec from
the position of the candidate MASTER afterglow position (GCN #16972) which
has been confirmed to be fading by GROND (GCN #16977), and does not match
any previously catalogued source. The source is significantly brighter
than the RASS limit and therefore we suggest that this is the X-ray
afterglow of GRB 141028A. More observations will be required to determine
if the source is fading in X-rays.
The results of the automatic processing for this source are available at
http://www.swift.ac.uk/xrt_products/TILED_GRB00030/index_4.php This
circular is an official product of the Swift-XRT team.
GCN Circular 16977
Subject
GRB 141028A: GROND Afterglow confirmation (MASTER source)
Date
2014-10-29T02:03:03Z (12 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
J. F. Graham (MPE Garching), D. A. Kann (TLS Tautenburg), P. Schady, and
J. Greiner (both MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 141028A (Fermi trigger 436186489; LAT
detection: Bissaldi et al., GCN #16969; GBM Detection: Roberts; GCN
#16971) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).
Observations started at 23:57 UT on October 28th, approximately 13 hours
after the GRB trigger. They were performed at an airmass of 1.2 and seeing
of 1".4.
At the position of the MASTER candidate afterglow (Gorbovskoy, GCN #16972)
we detect a bright source at
RA (J2000.0) = 322.60226 = 21:30:24.54
DEC (J2000.0) = -0.231314 = -00:13:52.7
with an error of 0".5.
Based on images with an exposure time of 1500 s in the optical and 1200 s
in the NIR, centered at 0.55305 days after the trigger, we estimate
preliminary magnitudes and limits (all in AB system) for this source of:
g' = 20.76 +/- 0.02 mag
r' = 19.93 +/- 0.01 mag
i' = 19.70 +/- 0.02 mag
z' = 19.49 +/- 0.02 mag
J = 19.24 +/- 0.11 mag
H = 18.94 +/- 0.08 mag
K > 18.3 mag
Compared to the MASTER detection, the source has faded significantly. We
also detect a fading by 0.1 +/- 0.03 mag over the time span of an hour.
Furthermore, the SED is adequately described by a power-law of slope beta
= 1.1, with a possible g'-band dropout, which may point to a redshift of
around 3 (which would make this a luminous afterglow).
At the position of the XRT source reported in the GRB_COUNTERPART POSITION
NOTICE (Source 3 at http://www.swift.ac.uk/xrt_products/TILED_GRB00030/),
we detect no source down to limiting magnitudes of:
g' > 24.5 mag
r' > 24.4 mag
i' > 23.7 mag
z' > 23.4 mag
J > 20.9 mag
H > 20.6 mag
K > 18.3 mag
We therefore deem it likely the MASTER source represents the afterglow of
GRB 141028A.
Given magnitudes are calibrated against SDSS field stars (g'r'i'z')
and 2MASS field stars (JHK) and are not corrected for the expected
Galactic foreground extinction corresponding to a reddening of E_(B-
V) = 0.05 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular 16975
Subject
IPN triangulation of GRB 141028A
Date
2014-10-28T21:30:37Z (12 years ago)
From
Kevin Hurley at UCBerkeley/SSL <khurley@ssl.berkeley.edu>
K. Hurley, on behalf of the IPN,
J. Goldsten, on behalf of the MESSENGER NS GRB team, and
V. Connaughton, M. S. Briggs, C. Meegan, and V. Pelassa, on behalf of the Fermi
GBM team, report:
GRB 141028A (Bissaldi et al. GCN 16969, Roberts et al. GCN 16971) has
also been observed by MESSENGER, so far. We have triangulated it to a preliminary,
3 sigma annulus, centered at RA, Dec = 16.520, +5.123 degrees, with radius
R=54.469 +/- 0.200 degrees. This annulus intersects the LAT error circle
at two points:
RA Dec
322.487 deg -0.619 deg
322.416 deg +0.002 deg
forming an error box whose area is approximately 0.03 degrees.
This triangulation may be improved.
A map has been posted at ssl.berkeley.edu/ipn3/141028A
GCN Circular 16973
Subject
GRB 141028A Tiled Swift observations
Date
2014-10-28T19:48:52Z (12 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 series of observations, tiled on the sky, of the
Fermi/LAT GRB 141028A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00030
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the Fermi/LAT event is high: 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; and 2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.
GCN Circular 16972
Subject
GRB 141028A: MASTER OT candidate detection
Date
2014-10-28T19:35:30Z (12 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
E. Gorbovskoy, V. Lipunov, N.Tyurina, M.Pruzhinskaya, V.Kornilov,
D.Kuvshinov, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Denisenko
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A. Gabovich
Blagoveschensk Educational State University, Blagoveschensk
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University
V.Krushinski, I.Zalozhnih, A. Popov
Ural Federal University, Kourovka
Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
Claudio Mallamaci, Carlos Lopez and Federico Podest
Observatorio Astronomico Felix Aguilar (OAFA)
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in
Kislovodsk was pointed to the GRB141028A (GCN 16969, Bissaldi) in survey mode.
MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec)
= 21h 30m 24.51s -00d 13m 52.3s on 2014-10-28.76451 UT.
The OT unfiltered magnitude is 18.9m (limit 19.9m).
The OT is seen in 12 images. There is no minor planet at this place.
We have reference image without OT on 2014-07-22.97505 UT with unfiltered
magnitude limit 19.7m.
Spectral observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/213024.51-001352.3.png
This message may be cited.
GCN Circular 16971
Subject
GRB 141028A: Fermi GBM detection
Date
2014-10-28T19:00:19Z (12 years ago)
From
Oliver Roberts at UCD/Fermi <oliver.roberts@ucd.ie>
O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:
"At 10:54:46.78 UT on 28 October 2014, the Fermi Gamma-Ray
Burst Monitor triggered and located GRB 141028A
(trigger 436186489 / 141028455), which was also detected by
the LAT (Bissaldi et al. 2014, GCN 16969). The GBM on-ground
location, using the Fermi GBM trigger data, is consistent with
the LAT location.
The trigger resulted in an Autonomous Repoint Request (ARR)
that was accepted and the spacecraft slewed to the GBM in-flight
location.
The on-ground calculated location, using the GBM trigger
data, is RA = 316.32, DEC = +1.67, with an uncertainty
of 1.0 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is about 19 degrees.
The GBM light curve consists of a single episode with a duration
(T90) of about 31.5 s (50-300 keV). The time-averaged spectrum
from T0+0s to T0+31.7s is well fit by a Band function with
Epeak = 249.9 (+/-12.6) keV, alpha = -0.71 +/- 0.03 , and
beta = -1.93 (+/-0.03).
The event fluence (10-1000 keV) in this time interval is
(3.478 +/- 0.009)E-05 erg/cm^2. The 1-sec peak photon flux
measured starting from T0+12.6 s in the 10-1000 keV band
is 17.3 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
GCN Circular 16969
Subject
GRB 141028A: Fermi-LAT detection
Date
2014-10-28T17:34:43Z (12 years ago)
From
Elisabetta Bissaldi at U.Innsbruk/IAPP <Elisabetta.Bissaldi@uibk.ac.at>
E. Bissaldi (University & INFN Trieste), J. L. Racusin (NASA/GSFC),
F. Longo (University & INFN Trieste), D. Kocevski (NASA/GSFC),
G. Vianello (Stanford Univ.) and M. Arimoto (Tokyo Tech)
report on behalf of the Fermi-LAT team:
At 10:54:46.78 on October 28, 2014, Fermi-LAT detected high-energy
emission from GRB 141028A, which was also detected by Fermi-GBM
(trigger 436186489/141028455) and initiated an autonomous repoint
of the spacecraft.
The best LAT on-ground location is found to be
RA, Dec 322.70, -0.28 (J2000)
with an error radius of 0.4 deg (90% containment, statistical error only).
This was 25 deg from the LAT boresight at the time of the trigger.
An improved position may be released when additional data is
downlinked from the spacecraft.
The data from the Fermi-LAT show a significant increase in the event
rate at a position consistent with the GBM localization.
More than 20 photons above 100 MeV are observed from trigger
time T0 up to T0+600 s, when the position of the burst moved
out of the LAT FoV.
The highest-energy photon is a 3.9 GeV event which is observed
160 seconds after the GBM trigger.
A Swift ToO has been approved for this burst.
The Fermi-LAT point of contact for this burst is
Makoto Arimoto (arimoto@hp.phys.titech.ac.jp).
The Fermi-LAT is a pair conversion telescope designed to cover
the energy band from 20 MeV to greater than 300 GeV.
It is the product of an international collaboration between
NASA and DOE in the U.S. and many scientific institutions
across France, Italy, Japan and Sweden.