GRB 171030A

A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN,

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and

S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, report:

A short-duration GRB 171030A has been detected by
Fermi (GBM trigger 531077390), INTEGRAL (SPI-ACS),
and Swift (BAT), so far, at about 62985 s UT (17:29:45).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
------------------------------------
   RA(2000), deg  Dec(2000), deg
------------------------------------
  Corners:
    47.7467      -25.6001
    37.3056      -48.8763
   117.4353      -11.9668
   118.1759      -5.9280
------------------------------------
The error box maximum dimension is 79.5 deg
(the minimum one is 5.9 deg).

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB171030_T62985/IPN

The time history and spectrum will be given in forthcoming GCN 
Circulars.

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the Swift/BAT GRB 171030A. 
Automated analysis of the XRT data will be presented online at
http://www.swift.ac.uk/ToO_GRBs/00020783

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Swift/BAT event. 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; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.

[GCN OPS NOTE(01nov17): Per author's request, the GRB name in the Subject-line
and in the first line has been changed from "1701030" to 171030A".

V. D'Elia (SSDC), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. Malesani (DARK/NBI), J.A. Kennea (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU) and P.A. Evans (U. Leicester) report on behalf of the Swift team:

At 17:29:45.12 UT on 2017-10-30, Swift BAT detected the rate increase associated with a short Fermi/GBM burst (Fermi trigger 531077390, BAT trigger #784509), also detected by INTEGRAL, and later broadly localized with the Interplanetary Network (IPN) using data from all three spacecraft (GCN # 22076).

On-board imaging found no sources above a 6.5 sigma image threshold, but ground analysis showed that a sub-threshold peak (5.8 sigma) in the image domain was consistent with the IPN error box and the Fermi/GBM 2 sigma localization. This image peak was about half the intensity that would be normally expected based on the count rate excess, but this is within the range of plausible variation allowed by statistics and systematics.  We also note that the IPN and Fermi localizations have a large fraction of their area outside of the BAT FOV, where BAT has rate-increase sensitivity but no localization ability.  Therefore, the data are consistent with locations both at the sub-threshold image peak, and outside of the FOV.

A Swift XRT ToO observation was requested for the purpose of determining whether there was an afterglow at the image peak location. The BAT on-board calculated location is  RA, Dec 68.671, -15.422 which is
RA(J2000) = 04h 34m 41.0s
Dec(J2000) = -15d 25� 19.2"
with an uncertainty of 3 arcmin (radius, 90% containment).

Swift-XRT has performed follow-up observations of the Swift/BAT-detected burst GRB 171030A, collecting 4.0 ks of Photon Counting (PC) mode data between T0+108.9 ks and T0+127.0 ks.

No X-ray sources have been detected consistent with being within 296 arcsec of the Swift/BAT position. The 3-sigma upper limit in the field is 0.003 ct  s^-1, corresponding to a 0.3-10 keV observed flux of 1.2e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum).

Two uncatalogued sources were detected too far from the GRB position to be likely afterglow candidates.

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
http://www.swift.ac.uk/ToO_GRBs/00020783.

The Swift/UVOT observed the field of GRB 171030A three times between 109 ks and 116 ks after the trigger for a total exposure of 1751 s.  All the exposures used the UVW2 filter. No new source was found with an upper limit of 21.0 mag. No correction has been made  for the Galactic extinction due to the reddening of E(B-V) = 0.22 in the direction of the burst (Schlegel et al. 1998).

Based on the non-detection of an afterglow by XRT, we conclude that GRB 171030A was either outside of the BAT FOV, and thus not associated with the location of the sub-threshold image peak, or too faint to be detected at the time of the Swift ToO.

This is an official product of the Swift team.

R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 17:29:45.12 UT on 30 October 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 171030A (trigger 531077390 / 171030729)
which was also detected by Swift/BAT and INTEGRAL/SPI-ACS, as reported
by the Interplanetary Network (GCN 22076
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 ). The GBM on-ground location is
consistent with the Swift/BAT location (GCN 22078
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 ).

The angle from the Fermi LAT boresight at the GBM trigger time is 135
degrees.

The GBM light curve shows a single peak
with a duration (T90) of about 0.1 s (50-300 keV).
The time-averaged spectrum from T0-0.06 s to T0+0.00 s is
adequately fit by a simple power law function with index -1.11 +/- 0.07.

The event fluence (10-1000 keV) in this time interval is
(1.7 +/- 0.2)E-07 erg/cm^2. The 0.064-sec peak photon flux measured
starting from T0-0.064 s in the 10-1000 keV band
is 11.6 +/- 2.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."

V. Lipunov, 
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University

D.Svinkin
Ioffe Institute, St Petersburg

E. Gorbovskoy, N.Tyurina, D.Kuvshinov
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University


We present NSs merging rate MAP inside local 50 Mpc distance (see 
Lipunov, V. M.; Nazin, S. N.; Panchenko, I. E.; Postnov, K. A.; 
Prokhorov, M. E. The gravitational wave sky, Astronomy and 
Astrophysics, v.298, p.677, 1995; Lipunov et al., 2017,
https://arxiv.org/ftp/arxiv/papers/1710/1710.05911.pdf ).

There are two common regions belong to IPN (Kozlova et al., GCN 22076
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 ) 
(black   on picture) aproximated next 
rectangle:

First:

  [37,-35]
  [60,-20]
  [60,-30]
  [40,-45]


Second:

[73,-10]
[80,-04]
[80,-11]
[73,-21]

Maps are available at
http://observ.pereplet.ru/images/VLNSmergrate.jpg

The possible Swift localisation () is shown by green square.


Common IPN + NSsMerging probability Map region are available

http://observ.pereplet.ru/images/GRB171030A_1.txt
http://observ.pereplet.ru/images/GRB171030A_2.txt

The message may be cited.

V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, D.Kuvshinov, 
P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko, I.Gorbunov, A.V.Krylov
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University

D.Svinkin
Ioffe Institute, St Petersburg

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

K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk
Irkutsk State University

A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory

V. Yurkov, A. Gabovich, Yu. Sergienko
Blagoveschensk Educational State University, Blagoveschensk

D. Buckley, S. Potter, A. Kniazev, M. Kotze
South African Astronomical Observatory


GRB171030A was detected by Fermi (Hamburg  and C. Meegan, GCN 22079
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 ) at 
17:29:45.12 UT on 30 October 2017. This is was slightly soft short GRB can be 
off-axis gamma emission produced by near (<50-100 Mpc) mergin Neutron Stars 
(Burgess et al., Viewing short Gamma-ray Bursts from a different angles, 
arXiv:1710.05823
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 , https://arxiv.org/abs/1710.05823
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  ).


MASTER Robotic Net inspected IPN error box (Kozlova et al., GCN 22076
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 ) and its 
common parts with NSs merging rate MAP inside local 50 Mpc distance (see 
Lipunov, V. et al., GCN 22080
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  ).
MASTER-OAFA, MASTER-IAC, MASTER-Tunka, MASTER-Kislovodsk and MASTER-SAAO 
covered 99% of the full IPN error box 
(1248 square degrees).
The common region of the NSs merging rate MAP inside local 50 Mpc distance and 
IPN has 112 square degrees and 256 square degrees correspondingly.
The avarage upper limit during this inspection was 18.5. The best limit 
was 19.5, worst was 18.0.

The coverage map is available at
https://master.sai.msu.ru/site/master2/ligo_one.php?id=10072

  We  found 3  OTs:

1). MASTER OT J031444.34-471210.0 detection - New Dwarf Nova (Lipunov et 
al., ATel 
- 10928).

MASTER-OAFA auto-detection system ( <A 
HREF="http://www.hindawi.com/journals/aa/2010/349171/">Lipunov et al., "MASTER 
Global Robotic Net", Advances in Astronomy, 2010, 30L</A> )
  discovered OT source at (RA, Dec) = 03h 14m 44.34s -47d 12m 10.0s on 
2017-11-03.21736 UT.

The OT unfiltered magnitude is 17.1m (mlim=18.6m).

The discovery and reference images are available at

http://master.sai.msu.ru/static/OT/031444.34-471210.0.png


2) MASTER OT J034515.40-015216.5 detection - CSS 090219:034515-015216 U Gem + 
Ursae Majoris Type Variables  at  outburst .

MASTER-IAC auto-detection system discovered OT source at
(RA, Dec) = 03h 45m 15.40s -01d 52m 16.5s on 2017-10-31.14317 UT.
The OT B magnitude is 14.6m (limit 18.3m), R magnitude is 14.4 .

We have reference unfiltered images on
2015-12-03 00:28:33.686 m_OT=19.5
2016-08-15 05:24:15.584 m_OT=19.3
2017-03-15 20:57:59.196 m_OT=19.6.

This OT is also known as CSS UGSU 
http://www.aavso.org/vsx/index.php?view=detail.top&oid=193659

The discovery and reference images are available at:

http://master.sai.msu.ru/static/OT/034515.40-015216.5.png

3). MASTER OT J034412.48-263556.5 discovery - PSNIa before maximum   in 
0"W,21"S of  PGC134086 galaxy

MASTER-OAFA auto-detection system ( <A 
HREF="http://www.hindawi.com/journals/aa/2010/349171/">Lipunov et al., "MASTER 
Global Robotic Net", Advances in Astronomy, 2010, 30L</A> )
  discovered OT source at (RA, Dec) = 03h 44m 12.48s -26d 35m 56.5s on 
2017-11-06.23799 UT.


The OT unfiltered magnitude is 18.7m (mlim=18.7m). 
This OT(PSN) is  in 0"W,21"S of PGC134086  (Btc=16.2, V_GSR,LG=19958km/s, 
http://leda.univ-lyon1.fr/ledacat.cgi?PGC134086)_B=-21.1+-0.9 
). The galaxy distance is aboute 300 Mpc.



There are 5 images with PSN:


2017-11-06 05:27:16UT

2017-11-06 05:42:42UT

2017-11-06 07:34:52UT

2017-11-06  07:38:38UT

2017-11-06 07:42:22UT

We have reference images without OT on 2017-09-27.19196 UT with unfiltered 
magnitude limit 20.1m, on <b> 2017-11-03 06:18:44</b> with mlim=17.7.  It   gives 
possibility to be a young PSN before maximum.

Spectral observations are required.

The only third optical transient  MASTER OT J034412.48-263556.5 is 
potentially 
can be connected with collapse processes produce fast rotating NS (see 
Lipunov, V.M.,2017,  Double O-Ne-Mg  white dwarfs merging as the source of the 
powerfull gravitational waves  for LIGO/VIRGO type interferometers, New 
Astronomy, Volume 56, p. 84-85). But it is very bright and
very late  for Kilonova after 30 October 2017 NSs merging.


Maps are available at
http://observ.pereplet.ru/images/VLNSmergrate.jpg

The possible Swift localisation (D'Elia etal.,  GCN 22078
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  ) is shown by green 
square. Its optical limit is 19.5 (unfiltered and B) and 18.0 (I) between 
2017-10-31 22:43:33 UT and  2017-11-01  02:37:44 UT


Common IPN + NSsMerging probability Map two regions are available

http://observ.pereplet.ru/images/GRB171030A_1.txt
http://observ.pereplet.ru/images/GRB171030A_2.txt

The message may be cited.

Xiaofeng Wang
Physics Department and Tsinghua Center for Astrophysics, Tsinghua 
University, Beijing, 100084, China;

Jujia Zhang
Yunnan Observatories, Chinese Academy of Sciences,Kunming, 650011, China

Sahu D.K.
Indian Institute of Astrophysics

Lipunov V.,  Tiurina N., Gorbovskoy E.,
Lomonosov Moscow State SU, SAI


MASTER OT J034412.48-263556.5 (Lipunov et al., ATEL #10929 ; Lipunov et 
al. GCN #22102
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 ) was observed at  Lijiang 2.4m telescope for this 
transient, which shows blue and featureless continuum  like that 
of GRB170817A (Kilonova) but much brighter.
   We used YFOSC+G3 to  get the spectrum.

The second Spectrum was taken at 2-m aperture optical-infrared telescope, 
the Himalayan Chandra Telescope (HCT) with HFOSC (Hanle Faint Object 
Spectrograph Camera  https://www.iiap.res.in//iao/hfosc.html ) at Indian 
Astronomical Observatory https://www.iiap.res.in//iao/iao.html

The authors are grateful to prof. S.I.Blinnikov for comments.

Follow up observations are required.

The message may be cited.