GRB 161017A
GCN Circular 20064
Subject
GRB 161017A: Swift detection of a burst with a bright optical afterglow
Date
2016-10-17T18:04:12Z (9 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
E. Troja (NASA/GSFC/UMCP), D. N. Burrows (PSU),
P. D'Avanzo (INAF-OAB), N. Gehrels (NASA/GSFC), J. A. Kennea (PSU),
N. P. M. Kuin (UCL-MSSL), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC),
A. Melandri (INAF-OAB), K. L. Page (U Leicester), D. M. Palmer (LANL)
and T. N. Ukwatta (LANL) report on behalf of the Swift Team:
At 17:51:51 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 161017A (trigger=718023). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 142.765, +43.142 which is
RA(J2000) = 09h 31m 04s
Dec(J2000) = +43d 08' 30"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a multi-peaked
structure with a duration of about 160 sec. The peak count rate
was ~2100 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 17:52:48.8 UT, 57.7 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 142.7681, 43.1300 which is equivalent to:
RA(J2000) = +09h 31m 4.34s
Dec(J2000) = +43d 07' 48.0"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
location is 43 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 3.24e-09 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of nominal 150.000 seconds with the White
filter starting 67 seconds after the BAT trigger. There is a candidate
afterglow in the list of sources generated on-board at
RA(J2000) = 09:31:04.58 = 142.76910
DEC(J2000) = +43:07:36.3 = 43.12675
with a 90%-confidence error radius of about 1.10 arc sec. This position is 12.0
arc sec. from the center of the XRT error circle. The estimated magnitude is
13.86. No correction has been made for the expected extinction corresponding to
E(B-V) of 0.02.
Burst Advocate for this burst is E. Troja (eleonora.troja 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 20067
Subject
GRB 161017A: Enhanced Swift-XRT position
Date
2016-10-18T04:38:04Z (9 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester)
report on behalf of the Swift-XRT team.
Using 2929 s of XRT Photon Counting mode data and 6 UVOT
images for GRB 161017A, 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 = 142.76888, +43.12633 which is equivalent
to:
RA (J2000): 09h 31m 4.53s
Dec (J2000): +43d 07' 34.8"
with an uncertainty of 1.4 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 20068
Subject
GRB 161017A: Fermi GBM observation
Date
2016-10-18T05:00:56Z (9 years ago)
From
C. Michelle Hui at MSFC/Fermi-GBM <c.m.hui@nasa.gov>
C. M. Hui (NASA/MSFC) and C Meegan (UAH)
report on behalf of the Fermi GBM Team:
At 17:52:08.26 UT on 17 October 2016, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 161017A (trigger 498419532/161017745),
which was also detected by Swift (Troja et al., GCN 20064).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 125 degrees.
The GBM light curve shows two peaks with a duration (T90)
of about 32 s (50-300 keV). The time-averaged spectrum
from T0-22.1 s to T0+8.6 s is adequately fit by a power law function
with an exponential high-energy cutoff.
The power law index is -1.04 +/- 0.09 and the cutoff energy,
parameterized as Epeak, is 298.50 +/- 45.00 keV
The event fluence (10-1000 keV) in this time interval is
(7.02 +/- 0.43)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+4.3 s in the 10-1000keV band is 5.6 +/- 0.5 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog.
GCN Circular 20069
Subject
GRB 161017A: Redshift from GTC
Date
2016-10-18T06:22:19Z (9 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. A. Kann (TLS Tautenburg),
C. Thoene (IAA-CSIC), L. Izzo (IAA-CSIC), R. Sanchez-Ramirez (IAA-CSIC),
Z. Cano (IAA-CSIC), K. Bensch (IAA-CSIC), D. Garcia-Alvarez (IAC, ULL,
GRANTECAN) and D. Perez Valladares (GRANTECAN) report :
We observed the afterglow of GRB 161017A (Yurkov et al., GCN 20063,
Troja et al. GCN 20064) with OSIRIS at the 10.4m GTC telescope on
La Palma (Spain). The observations started at 04:38:44 UT (10.78 hr after
the burst) and consist of 3 x 900 s spectra using grism R1000B, which
covers the spectral region between 3700 and 7800 AA at a resolution of
R ~ 1000.
The r-band acquisition image shows the afterglow at a magnitude of r(AB) =
18.24+/-0.07, as compared to several SDSS stars.
The spectrum shows a strong continuum with weak features of SiII, CIV, AlII,
and FeII at a common redshift of 2.013, which we identify as the redshift of the
GRB. Additionally, we detect two intervening systems at z=0.916 and z=1.370,
both with MgII features.
GCN Circular 20070
Subject
GRB 161017A: MITSuME Akeno Optical Observation
Date
2016-10-18T07:08:21Z (9 years ago)
From
Taketoshi Yoshii at Tokyo Tech <yoshii.t.ac@m.titech.ac.jp>
T.Fujiwara, Y.Saito, Y. Tachibana, T. Yoshii, Y. Yano,
Y.Ono, S.Harita, Y.Muraki, K.Morita, T.Ozawa, K.Saisho,Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 161017A (E. Troja et al., GCN
Circular #20064) 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 2016-10-17 17:52:42 UT (51 sec after the burst) and
we detected the optical counterpart in g', Rc and Ic band.
The measured magnitudes were listed as follows.
We obtained following results for the magnitudes.
T0+[sec] MID-UT T-EXP[sec] g' Rc Ic
-------------------------------------------------------------------------------------------------------
51 17:52:57 30 14.55 +/- 0.06 13.78 +/- 0.05 13.38 +/- 0.06
87 17:55:41 240 14.35 +/- 0.05 13.61 +/- 0.04 13.25 +/- 0.04
331 18:03:41 600 15.50 +/- 0.05 14.73 +/- 0.04 14.42 +/- 0.04
996 18:28:35 2100 16.58 +/- 0.05 15.89 +/- 0.05 15.63 +/- 0.04
3320 19:15:35 2040 16.76 +/- 0.06 16.03 +/- 0.05 15.77 +/- 0.05
-------------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.
GCN Circular 20071
Subject
GRB 161017A: TNG optical observations
Date
2016-10-18T10:14:06Z (9 years ago)
From
Andrea Melandri at INAF-OAB <andrea.melandri@brera.inaf.it>
A. Melandri, P. D'Avanzo (INAF-OAB), V. D'Elia (INAF/OAR & ASI/ASDC), V. Lorenzi, Hristo Stoev (INAF-TNG) report on behalf of the CIBO collaboration:
We observed the field of GRB 161017A (Troja et al., GCN 20064) with the 3.6m Telescopio Nazionale Galileo (TNG) equipped with DOLoRes. Observations were carried out in the r-sdss filter. Observations started on Oct 18 at 03:51:18 UT (~10 hours after the burst) and consist in a single image lasting 120 seconds.
The optical afterglow (Yurkov et al. GCN 20063; Troja et al. GCN 20064; de Ugarte Postigo et al. GCN 20069; Fujiwara et al. GCN 20070) is detected with a magnitude r(AB) = 17.9 +/- 0.1 (calibrated against nearby SDSS stars).
GCN Circular 20072
Subject
GRB161017A: optical observations with 1-m LCOGT McDonald
Date
2016-10-18T11:18:07Z (9 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), C.G. Mundell
(U. Bath), A. Gomboc (U. Nova Gorica) on behalf of a large collaboration
report:
The 1-m LCOGT McDonald telescope began observing Swift GRB161017A (Troja
et al., GCN 20064) in the SDSS r filter on October 18, 10:03 UT (~0.67
days since the GRB). We detect the optical afterglow (Yurkov et al. GCN
20063; Troja et al. GCN 20064; de Ugarte-Postigo et al. GCN 20069;
Fujiwara et al GCN 20070; Melandri et al. GCN 20071) with r=18.95 +-
0.10 mag at 0.68 days mid epoch, as calibrated against nearby SDSS stars.
GCN Circular 20073
Subject
GRB 161017A: Swift-XRT refined Analysis
Date
2016-10-18T11:27:12Z (9 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P.A. Evans (U. Leicester), A. Melandri (INAF-OAB), P. D'Avanzo
(INAF-OAB), V. D'Elia (ASDC), T.G.R. Roegiers (PSU), L.M. McCauley
(PSU), J.A. Kennea (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U.
Leicester) and E. Troja report on behalf of the Swift-XRT team:
We have analysed 7.6 ks of XRT data for GRB 161017A (Troja et al. GCN
Circ. 20064), from 51 s to 46.2 ks after the BAT trigger. The data
comprise 595 s in Windowed Timing (WT) mode (the first 5 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 Beardmore
et al. (GCN Circ. 20067).
The late-time light curve (from T0+4.5 ks) can be modelled with a
power-law decay with a decay index of alpha=1.04 (+/-0.06).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.656 (+/-0.019). The
best-fitting absorption column is 7.5 (+/-0.7) x 10^21 cm^-2, at a
redshift of 2.013, in addition to the Galactic value of 1.8 x 10^20
cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index
of 1.99 (+0.10, -0.07) and a best-fitting absorption column of 4 (+20,
-4) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum is 3.2 x 10^-11 (3.4 x
10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Galactic foreground: 1.8 x 10^20 cm^-2
Intrinsic column: 4 (+20, -4) x 10^20 cm^-2 at z=2.013
Photon index: 1.99 (+0.10, -0.07)
If the light curve continues to decay with a power-law decay index of
1.04, the count rate at T+24 hours will be 0.042 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.3 x
10^-12 (1.4 x 10^-12) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00718023.
This circular is an official product of the Swift-XRT team.
GCN Circular 20074
Subject
GRB 161017A: Swift/UVOT Detection
Date
2016-10-18T12:34:01Z (9 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) and E. Troja (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 161017A
68 s after the BAT trigger (Troja et al., GCN Circ. 20064, Yurkov et
al., GCN Circ. 20063).
The UVOT source described in Troja et al., GCN Circ. 20064, is at a
position consistent with the enhanced XRT position (Beardmore et al.,
GCN Circ. 20067) and is found to be fading.
The preliminary UVOT position is:
RA (J2000) = 09:31:04.60 = 142.76915 (deg.)
Dec (J2000) = +43:07:36.3 = 43.12676 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
Preliminary detections using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early
exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 68 217 147 14.08 �� 0.02
v 609 629 20 15.14 �� 0.09
b 535 555 20 15.60 �� 0.06
u 280 529 246 14.56 �� 0.02
uvw1 658 661 2.7 15.5 �� 0.3
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 20075
Subject
GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
Date
2016-10-18T16:23:33Z (9 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V.A.Sadovnichy,
Lomonosov Moscow State University
M.I.Panasyuk, S.I.Svertilov, A.V.Bogomolov,
V.V.Bogomolov, N.L.Dzhioeva, A.M.Amelushkin, V.O.Barinova, A.F.Iyudin,
V.V.Kalegaev, D.Nguen, V.L. Petrov, I.V.Yashin, P.S.Kazarian
Physics Department, Skobel`tsyn Institute of Nuclear Physics, Moscow State
V. Lipunov, E.S. Gorbovskoy, N.Tyurina, D.Kuvshinov, M.Panchenko,
A.Kuznetsov, V.G.Kornilov, P. Balanutsa, E.Popova
Lomonosov Moscow State University, Sternberg Astronomical Institute
V.Yurkov, A.Gabovich, Yu.Sergienko
Blagoveschensk Educational State University, Blagoveschensk
N.M.Budnev, K.Ivanov, O.Gres, O.Chuvalaev, V.A.Poleshchuk, S.Yazev
Irkutsk State University
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
The Instituto de Astrofisica de Canarias
I. Park, J. Lee, S. Jeong
Department of Physics, Sungkyunkwan University, Seobu-ro, Jangangu, Suwonsi,
Korea
At 17:52:17 UT on 17 Sep 2016, the Lomonosov BDRG Gamma-ray Burst
Monitor (http://lomonosov.sinp.msu.ru/en/scientific-equipment-2/bdrg )
triggered GRB 161017A (E. Troja et al.,, GCN 20064).
GRB 161017A has several peaks LC, total duration ~100s,the energy range
70-300 keV.
The light curve is available at
http://master.sai.msu.ru/static/Lomonosov/GRB161017A_BDRG2.png
More information will be available at:
http://lomonosov.sinp.msu.ru/category/results/observation-gamma-ray-bursts
MASTER-Amur robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Blagoveschensk was pointed to the GRB161017A 21 sec after
notice time and 47 sec after Swift trigger time at 2016-10-17 17:52:38 UT
in two polarizations.
On our first (10s exposure) set we marginally found optical transient
at Yurkov et al. (GCN 20063) and Troja et al. (GCN 20064) position.
The 5-sigma upper limit has been about 14.5 mag .
The OT was became brighter up to maximum at 3-4 set .
The observations made on zenit distance = 53 degrees, galaxy latitude b =
47 degree.
The moon (96 % bright part) is 50 degrees above the horizon. The distance
between moon and object is 87
The sun altitude is -37.8 degree.
MASTER-Tunka robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Tunka (Baykal lake) was pointed to the GRB161017.74 75 sec
after notice time
and 103 sec after trigger time at 2016-10-17 17:53:34 UT. On our second
(20s exposure) set we haven`t found optical transient within SWIFT
error-box (ra=09 31 03 dec=+43 08 31 r=0.050000).
The 5-sigma upper limit has been about 12.5 mag.
The observations made on zenit distance = 65 degrees, galaxy latitude b =
47 degree.
The moon (96 % bright part) is 50 degrees above the horizon. The distance
between moon and object is 87 degrees.
The sun altitude is -45.9 degrees.
The low mahnitude limit because dense fog due to Irkut (Famost Sibirian
river) evaporation.
We imaged OT late.
MASTER-IAC robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located at Teide Observatory (Tenerife, Canary, Spain) was pointed to the
GRB161017A 32942 sec after trigger time at 2016-10-18 03:00:53 UT. On our
first (180s exposure) set we found optical transient on coaded images.
The 5-sigma upper limit has been about 17.8 mag
The observations made on zenit distance = 69 degrees, galaxy latitude b =
47 degrees. The moon (94 % bright part) is 75 degrees above the horizon.
The distance between moon and object is 82 degrees.
The sun altitude is -54.1 degree.
Our preliminary photometry is next:
Time Tstart Tmid Expt Site Filter Mag eMag Filter Mag eMag
17:52:38 47 52 10 MASTER-Amur P/ 15.69 1.0 P\ 15.46 1.0
17:53:07 71 76 10 MASTER-Amur P/ 14.05 0.3 P\ 13.99 0.3
17:53:03 96 106 20 MASTER-Amur P/ 13.87 0.2 P\ 13.63 0.2
17:54:03 131 146 30 MASTER-Amur P/ 13.90 0.3 P\ 13.80 0.3
17:54:46 175 195 40 MASTER-Amur P/ 14.34 0.3 P\ 14.34 0.3
17:55:41 229 254 50 MASTER-Amur P/ 15.03 0.4 P\
17:56:46 295 325 60 MASTER-Amur P/ 14.91 0.4 P\ 14.91 0.4
17:58:12 381 540 240 MASTER-Amur P/ 15.88 0.4 P\ 16.03 0.4
18:05:20 809 889 160 MASTER-Tunka P| 15.64 0.2
03:00:53 32942 33464 900 MASTER-IAC C 18.62 0.2
03:19:17 34046 34587 900 MASTER-IAC C 18.60 0.2
03:38:01 35170 35726 900 MASTER-IAC C 18.62 0.2
03:57:26 36335 36885 900 MASTER-IAC C 18.68 0.2
Preliminary OT light curve is available at
http://master.sai.msu.ru/static/GRB161017A.png
The message may be cited.
GCN Circular 20076
Subject
GRB 161017A: Swift-BAT refined analysis
Date
2016-10-18T17:08:51Z (9 years ago)
From
Tilan Ukwatta at LANL <tilan.ukwatta@gmail.com>
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), E. Troja (NASA/GSFC/UMCP),
T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+833 sec from the recent
telemetry downlink, we report further analysis of BAT
GRB 161017A (trigger #718023) (Troja, et al., GCN Circ. 20064).
The BAT ground-calculated position is
RA, Dec = 142.770, 43.125 deg which is
RA(J2000) = 09h 31m 04.8s
Dec(J2000) = +43d 07' 29.0"
with an uncertainty of 1.0 arcmin, (radius, sys+stat,
90% containment). The partial coding was 100%.
The mask-weighted light curve shows two main
episodes. The first multi-peak episode starts around T-5 sec,
and ends at ~T+50 sec. The second relatively weaker episode
starts at ~T+60 sec and ends around T+250 sec. T90 (15-350 keV)
is 216.3 +- 6.9 sec (estimated error including systematics).
The time-averaged spectrum from T-4.88 to T+233.42 sec is best
fit by a simple power-law model. The power law index of the
time-averaged spectrum is 1.55 +- 0.06. The fluence in the
15-150 keV band is 5.3 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak
photon flux measured from T+17.78 sec in the 15-150 keV band
is 2.8 +- 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/718023/BA/
GCN Circular 20077
Subject
GRB 161017A: GTC additional spectroscopy and refined redshift
Date
2016-10-18T18:18:16Z (9 years ago)
From
Alberto Castro-Tirado at Inst.de Astro. de Andalucia <ajct@iaa.es>
A. J. Castro-Tirado (IAA-CSIC), A. F. Valeev (SAO-RAS), V. V. Sokolov (SAO-RAS), P. Ferrero (IAA-CSIC), J. C. Tello (IAA-CSIC), Y. Hu (IAA-CSIC), B.-B. Zhang (IAA-CSIC), S. Jeong (SKKU and IAA-CSIC), J. Cepa (IAC), S. R. Oates (U. of Warwick), D. Garcia-Alvarez (IAC, ULL, GRANTECAN), D. Perez Valladares (GRANTECAN), N. Castro-Rodriguez (GRANTECAN) and S. Fernandez (GRANTECAN) on behalf of a larger collaboration, report:
Following the detection of GRB 161017A by Swift (Troja et al. GCNC 20064), Fermi (Hui and Meegan, GCNC 20068)
and Lomonosov (Sadovnichy et al. GCNC 20075), we observed the optical afterglow (Yurkov et al. GCNC 20063; Breeveld and Troja, GCNC 20074) with the 10.4m Gran Telescopio Canarias (GTC) at the Spanish island of La Palma, starting at 05:59 UT on Oct 18 (i.e. 12.1 hr post-burst), with both the R1000B and R2500I OSIRIS grisms, covering a combined range of 3800-10000 A. The reddest spectrum (convering the range between 7350 and 10000 A at a resolution of 2500) shows the strong Mg II doublet at a redshift z = 2.0127, consistent with the value reported by de Ugarte Postigo et al. (GCNC 20069). We also identify, in the bluest spectrum, other absorption lines (eg. SiII, FeII) and the two intervening systems reported on their GTC (+OSIRIS) R1000B spectrum taken 1.3 hr earlier than us.
We acknowledge excellent support from the GTC staff.
GCN Circular 20078
Subject
GRB 161017A: TNG spectroscopy and redshift confirmation
Date
2016-10-18T20:02:16Z (9 years ago)
From
Paolo D'Avanzo at INAF-OAB <paolo.davanzo@brera.inaf.it>
P. D'Avanzo (INAF-OAB), D. Malesani (DARK/NBI and DTU Space),
V. D'Elia (INAF/OAR & ASI/ASDC), A. Melandri (INAF-OAB), V. Lorenzi,
H. Stoev (INAF-TNG) report on behalf of the CIBO collaboration:
We observed the optical afterglow of GRB 161017A (Yurkov et al. GCN 20063;
Troja et al. GCN 20064; de Ugarte Postigo et al. GCN 20069; Fujiwara et al.
GCN 20070; Guidorzi et al. GCN 20072; Breeveld & Troja, GCN 20074; Sadovnichy
et al. GCN 20075) with the 3.6m Telescopio Nazionale Galileo (TNG) equipped
with the DOLoRes camera in spectroscopic mode. Observations were carried out
with the LR-B filter, covering the range 3500-8000 AA. The observations consisted of
two spectra, each one lasting 1200 s, carried out at a mean time of Oct 18.1852 UT
(~10.58 hours after the burst).
The spectrum shows a clear continuum. We detect absorption features consistent
with Li-alpha, Si II, C IV and Fe II lines at a common redshift of z = 2.01, together
with MgII intervening systems at z=0.92 and z=1.37, in agreement with the results
reported by de Ugarte Postigo et al. (GCN 20069) and Castro-Tirado et al. (GCN 20077).
GCN Circular 20079
Subject
GRB161017A optical R band observations with SARA-RM
Date
2016-10-18T21:59:31Z (9 years ago)
From
Dieter Hartmann at Clemson.U <hdieter@clemson.edu>
A. Kaur (Clemson U.), G. Henson (ETSU), and D. H. Hartmann (Clemson U.)
report optical observations of GRB161017A discovered by Swift (Yurkov et al.,
GCN Circ. 20063;Troja et al., GCN Circ. 20064).
The UVOT source described in Troja et al., GCN Circ. 20064, is at a
position consistent with the enhanced XRT position (Beardmore et al.,GCN
Circ. 20067) and is fading (Breeveld & Troja, GCN Circ. 20074) at the
preliminary UVOT position:
RA (J2000) = 09:31:04.60 = 142.76915 (deg.)
Dec (J2000) = +43:07:36.3 = 43.12676 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
We observed the field on 2016-10-18.17 UT centered at 09:31:4.65
+43:07:36.34 (J2000), imaging for 20 minutes in the Cousins R filter with
the 1.0m JKT telescope (SARA-RM) located on La Palma, Canary Isles, Spain.
We detect the fading source at an R magnitude of 17.606 +/- 0.017 using the
Andor IkonL 2048 x 2048 CCD (11.6 x 11.6 arc min). The photometric standard
GD71 was utilized for calibration.
SARA is described at http://saraobservatory.org
GCN Circular 20080
Subject
GRB 161017A: LT optical observations
Date
2016-10-19T08:29:40Z (9 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), C.G. Mundell
(U. Bath), A. Gomboc (U. Nova Gorica), N.R. Tanvir (U. Leicester) on
behalf of a large collaboration report:
The 2-m Liverpool Telescope observed Swift GRB161017A (Troja et al., GCN
20064) in the SDSS r and i filters on October 19, from 03:45 to 05:37 UT
(mid time~1.45 days since the GRB). We clearly detect the optical
afterglow (Yurkov et al. GCN 20063; Troja et al. GCN 20064; de
Ugarte-Postigo et al. GCN 20069; Fujiwara et al GCN 20070; Melandri et
al. GCN 20071) with the following values, as calibrated against nearby
SDSS stars:
Mid Time Exposure Filter Magnitude
(days) (s)
-------------------------------------------------------
1.42 5x120 SDSS-R 20.02 +- 0.03
1.42 5x120 SDSS-I 19.80 +- 0.03
-------------------------------------------------------
Compared with our previous report (Guidorzi et al. GCN 20072), we
estimate an average power-law decay index alpha~1.3 between 0.68 and
1.45 days post burst.
GCN Circular 20081
Subject
GRB161017A: NOEMA detection of the millimetre afterglow
Date
2016-10-19T16:15:03Z (9 years ago)
From
Steve Schulze at U of Iceland <sts30@hi.is>
S. Schulze (Weizmann Institute), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), M. Bremer, E. Chapillon, J. M. Winters (IRAM) and S. Martin (JAO) report on behalf a larger collaboration:
We conducted millimetre observations of GRB 161017A (Troja et al. GCN 20064) with the NOrthern Extended Millimeter Array (NOEMA; Plateau de Bure, France) at 93 and 133 GHz. Observations started at 6:51 UT on October 19 (i.e. 1.54 day after the burst).
We detect the afterglow at both frequencies. A preliminary analysis of the 93 GHz data reveals a flux density of 1.50 +/- 0.06 mJy. Further observations are scheduled.
We encourage follow-up observations at all frequencies.
GCN Circular 20082
Subject
Konus-Wind observation of GRB 161017A
Date
2016-10-19T17:42:56Z (9 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov,
D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline,
on behalf of the Konus-Wind team, report:
The long GRB 161017A (Swift-BAT trigger #718023:
Troja et al., GCN 20064, T0(BAT)=17:51:51 UT;
Fermi-GBM observation: Hui & Meegan, GCN 20068;
Lomonosov observation: Sadovnichy et al., GCN 20075)
was detected by Konus-Wind in the waiting mode.
The light curve shows an emission pulse which starts
~10 s before the BAT trigger, peaks at ~T0(BAT)+7 s,
and lasts till ~T0(BAT)+28 s.
The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB161017_T64311/
As observed by Konus-Wind, the burst had a fluence of
(8.5 �� 1.1)x10^-6 erg/cm2 and a 2.944-s peak energy flux,
measured from ~T0(BAT)+7 s, of (8.7 �� 0.2)x10^-7 erg/cm2
(both in the 20 - 10000 keV energy range).
Modeling the KW 3-channel time-integrated spectrum
(from T0(BAT)-10 s to T0(BAT)+28 s) by a power law
with exponential cutoff (CPL) model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -1.25 �� 0.16, and Ep = 289 �� 73 keV.
Modeling the KW 3-channel spectrum near the peak count rate with
the CPL model yields alpha = -1.17 �� 0.20, and Ep = 404 �� 136 keV.
Assuming the redshift z=2.013 (de Ugarte Postigo et al., GCN 20069)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.3, and Omega_Lambda = 0.7,
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is ~8.3x10^52 erg,
the peak luminosity L_iso is ~2.5x10^52 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is ~870 keV.
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.
GCN Circular 20142
Subject
GRB 161017A: 15 GHz upper limits from AMI
Date
2016-11-07T19:25:56Z (9 years ago)
From
Kunal Mooley at Oxford U <kunal.mooley@physics.ox.ac.uk>
K. P. Mooley (Hintze Fellow, Oxford), T. D. Staley, R. P. Fender
(Oxford), G. E. Anderson (Curtin), T. Cantwell (Manchester), D.
Titterington, S. H. Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods,
P. Scott (Cambridge), K. Grainge, A. Scaife (Manchester)
The AMI Large Array robotically triggered on the Swift alert for GRB
161017A (Troja et al., GCN 20064) as part of the 4pisky program, and
subsequent follow up observations were obtained up to 10 days
post-burst. Our observations at 15 GHz on 2016 Oct 18.14, Oct 19.33, Oct
21.30 and Oct 25.31 (UT) do not reveal any radio source at the XRT
location (Beardmore et al., GCN 20067), with 3sigma upper limits of 132
uJy, 84 uJy, 63 uJy and 78 uJy respectively.
We thank the AMI staff for scheduling these observations. The AMI-GRB
database is a log of all GRB follow up observations with the AMI, and is
available at http://4pisky.org/ami-grb/.