GRB 181013A
GCN Circular 23332
Subject
GRB 181013A: Swift detection of a probable burst
Date
2018-10-13T03:16:19Z (7 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
P. D'Avanzo (INAF-OAB), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
D. M. Palmer (LANL), B. Sbarufatti (PSU) and A. Tohuvavohu (PSU)
report on behalf of the Neil Gehrels Swift Observatory Team:
At 02:39:29 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 181013A (trigger=866783). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 207.601, +40.179, which is
RA(J2000) = 13h 50m 24s
Dec(J2000) = +40d 10' 43"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows several peaks
with a duration of about 25 sec. The peak count rate
was ~700 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 02:41:12.7 UT, 103.1 seconds after
the BAT trigger. No source was detected in 1.9 ks of promptly
downlinked data, which covered 96% of the BAT error circle. We are
waiting for the full dataset to detect and localise the XRT
counterpart.
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 106 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 25% of
the BAT 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
BAT 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
0.01.
Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.inaf.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/too.html.)
GCN Circular 23333
Subject
GRB 181013A: Global MASTER Net optical observations
Date
2018-10-13T06:51:18Z (7 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa,
A.Kuznetsov, V.V.Chazov, D. Vlasenko
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University
A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory
K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk
Irkutsk State University
V. Yurkov, A. Gabovich, Yu. Sergienko
Blagoveschensk Educational State University, Blagoveschensk
R. Podesta, Carlos Lopez and F. Podesta
Observatorio Astronomico Felix Aguilar (OAFA)
Hugo Levato and Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
The Instituto de Astrofisica de Canarias
D. Buckley, S. Potter, A. Kniazev, M. Kotze
South African Astronomical Observatory
MASTER-Kislovodsk robotic telescope (MASTER-Net:
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy,
vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station
of Pulkovo observatory) was pointed to the GRB181013A (D'Avanzo et al.,
GCN 23332) 21 sec after notice time and 54 sec after trigger time
at 2018-10-13 02:40:23 UT . On
our first (10s exposure) set we haven`t found optical transient within
SWIFT error-box (ra=207.596 dec=40.1783 r=0.05).
The 5-sigma upper limit has been about 13.2 mag
The message may be cited.
====================================================================
The galactic latitude b = 72 deg., longitude l = 82 deg.
The observations made on zenit distance = 71 deg.The moon (18 % bright
part) below the horizon (The altitude of the Moon is -50 deg. ).
Observations started at twilight.
The sun altitude is -7.8 deg.
The object can be observed till sunrise at 2018-10-13 03:20:48.
MASTER-Tavrida robotic telescope (MASTER-Net: http://observ.pereplet.ru,
Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in
Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the
GRB181013.11 129 sec after notice time and 202 sec after trigger time at
2018-10-13 02:42:51 UT. On our first (40s exposure) set we haven`t found
optical transient within SWIFT error-box (ra=207.596 dec=40.1781 r=0.1).
The 5-sigma upper limit has been about 17.4 mag
The message may be cited.
====================================================================
The galactic latitude b = 72 deg., longitude l = 82 deg.
The observations made on zenit distance = 75 deg.The moon (18 % bright
part) below the horizon (The altitude of the Moon is -54 deg. ).
Observations started at twilight.
The sun altitude is -13.6 deg.
The object can be observed till sunrise at 2018-10-13 03:56:18.
This message can be cited.
GCN Circular 23334
Subject
GRB 181013A: Swift-XRT afterglow detection
Date
2018-10-13T07:02:02Z (7 years ago)
From
Paolo D'Avanzo at INAF-OAB <paolo.davanzo@brera.inaf.it>
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), P. D'Avanzo
(INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), J.A. Kennea (PSU),
B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), A.P. Beardmore (U.
Leicester) and P. D'Avanzo (INAF-OAB) report on behalf of the Swift-XRT
team:
We have analysed 190 s of Photon Counting (PC) mode XRT data for the
Swift/BAT-detected burst GRB 181013A (D'Avanzo et al. GCN Circ. 23332),
collected between T0+115 s and T0+306 s.
An uncatalogued X-ray source is detected consistent with being within
296 arcsec of the Swift/BAT position and is above the RASS limit and
fading with 3-sigma significance, and is therefore likely the GRB
afterglow. The position of this source is RA, Dec=207.6518, +40.1082
which is equivalent to:
RA (J2000): 13:50:36.43
Dec(J2000): +40:06:29.5
with an uncertainty of 3.9 arcsec (radius, 90% confidence). This
position is 4.8 arcmin from the Swift/BAT position.
The light curve can be modelled with a power-law decay with a decay
index of alpha=7.6 (+0.4, -1.0).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 0.98 (+0.30, -0.19). The
best-fitting absorption column is consistent with the Galactic value
of 9.4 x 10^19 cm^-2 (Willingale et al. 2013). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum is 6.2 x 10^-11 (6.2 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 9 (+/-90) x 10^19 cm^-2
Galactic foreground: 9.4 x 10^19 cm^-2
Excess significance: <1.6 sigma
Photon index: 0.98 (+0.30, -0.19)
If the light curve continues to decay with a power-law decay index of
7.6, the count rate at T+24 hours will be 5.9 x 10^-21 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.6 x
10^-31 (3.6 x 10^-31) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis of the likely afterglow
are at http://www.swift.ac.uk/ToO_GRBs/00866783/Source1.php.
The results of the full analysis of the XRT observations are available
at http://www.swift.ac.uk/ToO_GRBs/00866783.
This circular is an official product of the Swift-XRT team.
GCN Circular 23335
Subject
GRB 181013A: Swift-BAT refined analysis
Date
2018-10-13T18:36:22Z (7 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI),
P. D'Avanzo (INAF-OAB), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC),
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-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 181013A (trigger #866783)
(D'Avanzo, et al., GCN Circ. 23332). The BAT ground-calculated position is
RA, Dec = 207.661, 40.107 deg, which is
RA(J2000) = 13h 50m 38.5s
Dec(J2000) = +40d 06' 26.8"
with an uncertainty of 3.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 81%.
The mask-weighted light curve shows peaks starting at ~T-5 sec and ending
at ~T+120 sec. T90 (15-350 keV) is 104.1 +- 53.5 sec (estimated error
including systematics).
The time-averaged spectrum from T+18.37 to T+123.97 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.82 +- 0.75. The fluence in the 15-150 keV band is 3.0 +- 1.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+18.80 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/866783/BA/
GCN Circular 23336
Subject
GRB 181013A: Swift/UVOT Upper Limits
Date
2018-10-14T00:31:04Z (7 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
N. P. M. Kuin (UCL-MSSL) and P. D'Avanzo (INAF-OAB)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 181013A 106 s
after
the BAT trigger (D'Avanzo et al., GCN Circ. 23332). No optical afterglow
consistent
with the XRT position (Osborne et al. GCN Circ. 23334) 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 867 1017 147 >20.2
u_FC 266 516 246 >19.1
white 867 1017 147 >20.2
u 266 516 246 >19.1
w1 818 7875 471 >20.4
m2 6035 7669 393 >19.6
w2 5624 7260 393 >20.8
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 23341
Subject
GRB 181013A: AbAO optical upper limit
Date
2018-10-15T18:04:31Z (7 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), S. Belkin (IKI), A. Pozanenko (IKI), R. Inasaridze
(AbAO), V. Ayvazian (AbAO), O. Kvaratskhelia (AbAO), G. Kapanadze (AbAO),
A. Volnova (IKI), I. Molotov (KIAM) report on behalf of larger GRB
follow-up collaboration:
We observed the field of the Swift GRB 181013A (D'Avanzoet al., GCN 23332)
with AS-32 (0.7m) telescope of Abastumani Observatory starting on Oct. 13
(UT) 15:23:15 . We do not detect any object within XRT position (Osborne
et al., GCN 23334). Preliminary photometry of the field is following:
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2018-10-13 15:23:15 0.54312 R 58*60 n/d n/d 21.0
The photometry is based on nearby SDSS-DR12 stars
SDSS-DR12_id R(Lupton)
J135025.82+400818.8 16.99
J135102.99+401021.5 16.36
J135015.70+400244.5 13.69
J135009.92+400351.8 13.87
J135009.71+400308.0 14.87