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From

Chao Wu at NAOC <wuchao.lamost@gmail.com>

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>

J.Y. Wei (NAOC), C. WU(NAOC), N.Leroy (LAL), L.P. Xin (NAOC), X.H. Han (NAOC), X.M. Meng(NAOC), L. Huang(NAOC), Y. Xu(NAOC), H.B. Cai(NAOC),J. Wang(NAOC), X.M. Lu(NAOC), Y.L. Qiu (NAOC), J.S. Deng(NAOC), L. Cao(NAOC),S. Wang(NAOC), E.W.Liang (GXU), Y.G. Yang (HBNU), B. Cordier(CEA),S.N. Zhang (NAOC),S. Basa (LAM), B.B. Wu(IHEP), Jean-Luc Atteia (IRAP), D. Götz (CEA), Cyril Lachaud (APC) on behalf of the SVOM Gravitational Astronomy group report:

 

We observed about 3200 square degree (8 sky regions) of the skymap of the advanced LIGO and Virgo trigger G211117, with Mini-GWAC(Mini Ground Wide Angle Camera), at Xinglong Observatory of NAOC equipped with U9000 camera(FOV~400 square degree/camera). Mini-GWAC comprises of 12 wide field angle cameras(aperture=7cm), working with unfiltered band. The observations are operated in time-series mode, taking one exposure in 15 seconds (10s exposure + 5s readout). The limit magnitude is ~12 mag in R band. The coordinates of the 8 regions and observation time are list following:

 

#- RA(J2000) Dec(J2000)    start-obs (UTC)    end-obs (UTC)

04:00:36.007  +50:05:10.042  2015-12-26 15:40:33.   2015-12-26 18:29:37.

06:39:58.264  +50:51:18.330  2015-12-26 15:40:27.   2015-12-26 20:04:36.

11:59:40.897  +69:49:54.653  2015-12-26 15:55:37.   2015-12-26 18:44:40.

12:00:34.275  +29:36:35.499  2015-12-26 17:20:33.   2015-12-26 22:39:34.

13:28:29.736  +10:21:33.849  2015-12-26 18:45:34.   2015-12-26 22:39:25.

14:40:48.753  +50:06:02.281  2015-12-26 18:31:44.   2015-12-26 21:34:50.

14:52:33.057  +10:50:27.095  2015-12-26 20:06:55.   2015-12-26 22:39:31

16:15:01.695  +29:45:14.593  2015-12-26 21:37:03.   2015-12-26 22:39:30.

 

Mini-GWAC is working in sky survey mode. The same sky regions were observed at Dec. 27 and 28. The image analysis is ongoing. Further observations of these fields are planned.

GCN Circular 18762

Subject

LIGO/Virgo G211117: iPTF Optical Transient Candidates

Date

2015-12-30T01:32:02Z (10 years ago)

From

Brad Cenko at NASA/GSFC <brad.cenko@nasa.gov>

S. B. Cenko (NASA/GSFC), Y. Cao (Caltech), R. Ferretti (Stockholm), L. Singer (NASA/GSFC), M. M. Kasliwal (Caltech), D. A. Perley (DARK), V. Bhalerao (IUCAA), R. Laher (IPAC), and T. Barlow (Caltech) report on behalf of the intermediate Palomar Transient Factory collaboration:

We have performed tiled observations of LIGO/Virgo 211117 using the Palomar 48-inch Oschin telescope (P48). The northern probability island from the BAYESTAR localization was observable from Palomar for most of the night of 2015 December 28 UT. Starting at 1:57 UT (1.93 d after the LIGO trigger), we imaged 140 fields spanning 952 square degrees.  We estimate a 51% prior probability that these fields contain the true location of the source.

A subset of these fields (731 square degrees, containing 37% of the probability localization) were processed through standard iPTF pipelines (those with previously obtained reference images).  Preliminary sifting through candidate variable sources using image subtraction by both our NERSC and IPAC pipelines, and applying standard iPTF vetting procedures, we flagged the following optical transient candidates for further follow-up:

  name        RA        Dec     time   mag     z    
--------- ---------- ---------- ----- ----- ------- 
iPTF15fdv  38.690081 +18.343843 02:13 19.13 0.03419   
iPTF15fhq  95.858071 +57.197553 09:47 18.92 0.04367  
iPTF15fhl 187.056654 +17.617051 12:42 19.09 0.04372   
iPTF15ffh  20.555150  -5.202027 03:46 18.93 0.06857
iPTF15fev  33.993552 +12.237196 02:42 17.64   0.018  
iPTF15fel  47.303172 +27.521374 02:27 18.96   0.049  
iPTF15ffz  22.266660  -8.227863 03:44 19.65   0.075
iPTF15ffi  35.437642  +7.617305 04:06 18.71   0.079
iPTF15fgk  30.201092 +10.255481 04:01 20.23    0.11
iPTF15ffk  35.650925  +6.877865 04:06 19.19    0.11
iPTF15ffo  36.172201  +7.150811 04:06 20.06    0.12
iPTF15fed  28.083908  +1.557477 02:00 19.93    0.22
iPTF15fib  33.144517 +17.763099 05:33 19.54    0.28
iPTF15feu  29.027105  +5.276469 02:03 20.44    0.70
iPTF15fgy  50.732616 +34.989945 05:47 19.52 
iPTF15fhd  88.700355 +57.911389 09:42 19.70
iPTF15fhp 137.184825 +55.451767 10:07 19.43
iPTF15fen  50.406434 +31.452250 02:28 19.53       H
iPTF15ffm  23.105842  -4.033150 03:47 19.81       H
iPTF15fhf 100.769436 +55.466998 09:11 19.22      G?

Where available, redshifts for nearby galaxy associations are provided, either spectroscopic (4 significant figures) or photometric redshifts from SDSS (2 significant figures).  

iPTF15fen and iPTF15ffm do not have obvious host galaxy associations in our reference imaging (H = hostless).  

iPTF15fhf is in the halo of a bright star, and may therefore be an image artifact (G = ghost).

We obtained optical spectra of iPTF15fdv and iPTF15fhl with the Gemini Multi-Object Spectrograph on the 8 m Gemini North telescope on 2015 December 29.  iPTF15fdv is a type II SN, with broad  P-Cygni features of H-alpha and Ca II.  It is very likely unrelated to the G211117 trigger.  Cross-correlation of the spectrum of iPTF15fhl with template spectra using the SuperNova IDentification code (Blondin and Tonry, ApJ, 2007, 666, 1024) reveals matches with a number of type Ic (and some Ib) supernovae.  Of particular interest is a similarity with the peculiar SN Ib 2005bf (Folatelli et al, ApJ, 2006, 641, 1039).  Further observations of this source are encouraged.

We further note that the source reported by Itoh et al. (GCN 18742Loading...
 
 ) is likely to be the minor planet 2606 Odessa, also visible in our P48 images near this time.

Positions are stated in the ICRS. Times are in UTC. Magnitudes are based on image subtraction; they are in the Mould R filter and in the AB system, calibrated with respect to point sources in SDSS as described in Ofek et
al. (2012, http://dx.doi.org/10.1086/664065Loading...
 
 ).

The diagram https://gracedb.ligo.org/apiweb/events/G211117/files/iptf.pdf shows the locations of our candidates and the P48 fields in relation to the LIGO/Virgo localization.

GCN Circular 18759

Subject

LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29

Date

2015-12-29T21:59:11Z (10 years ago)

From

David Rabinowitz at Yale U <david.rabinowitz@yale.edu>

SUBJECT: LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
FROM:  D. Rabinowitz, C. Baltay, N. Ellman (Yale), P. Nugent (LBNL)

  The La Silla-QUEST survey operating the 10-sq-deg QUEST camera on the 
1.0m ESO Schmidt at La Silla, Chile has covered th e ~90% confidence 
area for LVC event G21117 between Dec +27 and -13 deg. Analysis is 
ongoing, and further survey observa tions are planned. One target 
(LSQ15bvw) has been detected with high confidence outside the 90% 
confidence region:

LSQ Desig   V-mag    hh:mm:ss   dd:mm:ss        JD
  _________________________(J2000)___________________________
  LSQ15bvw     18.8    02:08:15.97  15:02:52.80 2457385.6006

LSQ15bvw appears as an isolated source not visible in years 2012 and 
2013.  Observations made 2015 Oct 28 and 29 (V mag 19.2 on JD 
2457384.6032 and V mag 18.8 on 2457385.6006) indicate that the object is 
brightening by ~ 0.5 mags per day.


Several other sources have been detected with lower confidence. All 
appear as likely supernova near the center of distant (z>0.01) host 
galaxies :


LSQ Desig   V-mag    hh:mm:ss   dd:mm:ss       JD
  _________________________(J2000)___________________________
LSQ15bvk     19.6    02:33:08.79  18:13:48.41 2457384.6297
LSQ15bvo     20.6    02:38:44.05  21:00:23.35   2457384.5775
LSQ15bvs     18.3    02:20:45.15 11:03:18.58   2457384.6032

GCN Circular 18748

Subject

LIGO/Virgo G211117: Further Swift-XRT sources

Date

2015-12-29T10:02:14Z (10 years ago)

From

Phil Evans at U of Leicester <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), J.A. Kennea (PSU), Scott Barthelmy
(NASA/GSFC), Dave Burrows (PSU), Sergio Campana (INAF-OAB), Brad Cenko
(NASA/GSFC), Neil Gehrels (NASA/GSFC), Paolo Giommi (ASI), Frank
Marshall (NASA/GSFC), John Nousek (PSU), Paul O'Brien (U. Leicester),
Julian Osborne (U. Leicester), David Palmer (LANL), Matteo Perri
(ASDC), Judy Racusin (NASA/GSFC), Mike Siegel (PSU), Gianpiero
Tagliaferri (INAF-OAB) report on behalf of the Swift team:

Swift has performed a series of 75 observations of galaxies (from the
GWGC catalogue) within the aLIGO error region for the aLIGO trigger
G211117, using the 'bayestar' GW localisation map. The observations
currently span from 140 ks to 217 ks after the aLIGO trigger, and cover
8.4 sq degrees on the sky (corrected for overlaps).

Since the last Swift GCN, we have detected a 9 X-ray sources, these are
either new detections, or have been given a higher 'rank' than in the
last circular. Each source is assigned a rank of 1-4 which describes
how likely it is to be related to the GW trigger, with 1 being the most
likely and 4 being the least likely. The ranks are described at
http://www.swift.ac.uk/ranks.php.

We have found:

  * 0 sources of rank 1
  * 0 sources of rank 2
  * 4 sources of rank 3
  * 5 sources of rank 4

We assumed a power-law spectrum with NH=3e20 cm^2, and Gamma=1.7

In addition to these sources a number of objects were detected and
reported in COUNTERPART notices, which are in fact artefacts around
extended sources, and are not point source detections. These spurious
sources are not reported below.

RANK 3 sources
==============

These are uncatalogued X-ray sources, however they are not brighter
than previous upper limits, so do not stand out as likely counterparts
to the GW trigger.
  
  Source 13:
  =============
    RA: 	 187.6968 ( = 12h 30m 47.23s)  J2000
    Dec:	 +12.3389 ( = +12d 20' 20.0")  J2000
    Error:	 +6.4 (radius, 90% confidence).
    Peak Rate:	 1.5e-01 +/- 5.4e-02 ct/sec (0.3-10 keV)
    Peak Flux:	 6.3e-12 +/- 2.3e-12 erg cm^-2 s^-1 (0.3-10 keV)
    RASS UL:	 2.5e+00 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)

       So the source is not significantly above the RASS 3-sigma limit
    There is no evidence for fading
    There is 1 GWGC galaxy within 200 kpc of the source.
  
  Source 24:
  =============
    RA: 	 188.0297 ( = 12h 32m 7.13s)  J2000
    Dec:	 +11.8560 ( = +11d 51' 21.6")  J2000
    Error:	 +7.5 (radius, 90% confidence).
    Peak Rate:	 1.6e-02 +/- 6.1e-03 ct/sec (0.3-10 keV)
    Peak Flux:	 6.7e-13 +/- 2.6e-13 erg cm^-2 s^-1 (0.3-10 keV)
    RASS UL:	 5.5e-02 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)

       So the source is not significantly above the RASS 3-sigma limit
    There is no evidence for fading
    NOTE: this source is not within 200 kpc of a GWGC galaxy.
  
  Source 27:
  =============
    RA: 	 187.9278 ( = 12h 31m 42.67s)  J2000
    Dec:	 +12.3292 ( = +12d 19' 45.1")  J2000
    Error:	 +11.7 (radius, 90% confidence).
    Peak Rate:	 1.8e-02 +/- 1.0e-02 ct/sec (0.3-10 keV)
    Peak Flux:	 7.7e-13 +/- 4.4e-13 erg cm^-2 s^-1 (0.3-10 keV)
    RASS UL:	 2.6e-01 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)

       So the source is not significantly above the RASS 3-sigma limit
    There is no evidence for fading
    NOTE: this source is not within 200 kpc of a GWGC galaxy.
  
  Source 44:
  =============
    RA: 	 187.8733 ( = 12h 31m 29.59s)  J2000
    Dec:	 +11.8772 ( = +11d 52' 37.9")  J2000
    Error:	 +6.7 (radius, 90% confidence).
    Peak Rate:	 1.4e-02 +/- 6.2e-03 ct/sec (0.3-10 keV)
    Peak Flux:	 5.9e-13 +/- 2.6e-13 erg cm^-2 s^-1 (0.3-10 keV)
    RASS UL:	 8.8e-02 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)

       So the source is not significantly above the RASS 3-sigma limit
    There is no evidence for fading
    NOTE: this source is not within 200 kpc of a GWGC galaxy.


RANK 4 sources
==============

These are catalogued X-ray sources, showing no signs of outburst
compared to previous observations, so they are not likely to be related
to the GW trigger.
  
  Source 6:
  =============
    RA: 	 207.1852 ( = 13h 48m 44.45s)  J2000
    Dec:	 -30.4960 ( = -30d 29' 45.6")  J2000
    Error:	 +6.0 (radius, 90% confidence).
    Peak Rate:	 5.1e-02 +/- 1.2e-02 ct/sec (0.3-10 keV)
    Peak Flux:	 2.2e-12 +/- 5.2e-13 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  XMMSL1 J134844.6-302948 in the XMM-NEWTON/XMMSLEWCLN
catalogue
    Separation:  2.7" from the XRT source
    Cat Rate:	 1.4e+00 +/- 3.7e-01 ct/sec (0.3-10 keV)
    Cat Flux:	 1.5e-11 +/- 3.9e-12 erg cm^-2 s^-1 (0.3-10 keV)
       So the source is not significantly above the catalogued flux
    The source may be fading, at the 0.3-sigma level.
    NOTE: this source is not within 200 kpc of a GWGC galaxy.
    A SIMBAD object `2XMM J134844.7-302943' is 3.7" away
    There is 1 2MASS object within the source's 3-sigma error radius
  
  Source 7:
  =============
    RA: 	 207.2700 ( = 13h 49m 4.80s)  J2000
    Dec:	 -30.2955 ( = -30d 17' 43.8")  J2000
    Error:	 +7.3 (radius, 90% confidence).
    Peak Rate:	 4.7e-02 +/- 1.2e-02 ct/sec (0.3-10 keV)
    Peak Flux:	 2.0e-12 +/- 5.3e-13 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  XMMSL1 J134904.4-301745 in the XMM-NEWTON/XMMSLEWCLN
catalogue
    Separation:  3.6" from the XRT source
    Cat Rate:	 1.6e+00 +/- 4.9e-01 ct/sec (0.3-10 keV)
    Cat Flux:	 1.7e-11 +/- 5.2e-12 erg cm^-2 s^-1 (0.3-10 keV)
       So the source is not significantly above the catalogued flux
    There is no evidence for fading
    There is 1 GWGC galaxy within 200 kpc of the source.
    A SIMBAD object `[RP98d] P6' is 6.3" away
    There is 1 2MASS object within the source's 3-sigma error radius
  
  Source 16:
  =============
    RA: 	 187.6792 ( = 12h 30m 43.01s)  J2000
    Dec:	 +12.3882 ( = +12d 23' 17.5")  J2000
    Error:	 +5.9 (radius, 90% confidence).
    Peak Rate:	 4.3e+00 +/- 1.2e+00 ct/sec (0.3-10 keV)
    Peak Flux:	 1.8e-10 +/- 5.2e-11 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  2RXP J123044.7+122331 in the ROSAT/ROSPSPC catalogue
    Separation:  28.9" from the XRT source
    Cat Rate:	 0.0e+00 +/- 0.0e+00 ct/sec (0.3-10 keV)
    Cat Flux:	 0.0e+00 +/- 0.0e+00 erg cm^-2 s^-1 (0.3-10 keV)
       So the source is not significantly above the catalogued flux
    The source may be fading, at the 0.7-sigma level.
    There is 1 GWGC galaxy within 200 kpc of the source.
    A SIMBAD object `[SFH81] 1157' is 7.9" away
  
  Source 23:
  =============
    RA: 	 187.8039 ( = 12h 31m 12.94s)  J2000
    Dec:	 +12.0537 ( = +12d 03' 13.3")  J2000
    Error:	 +6.5 (radius, 90% confidence).
    Peak Rate:	 7.0e-02 +/- 2.5e-02 ct/sec (0.3-10 keV)
    Peak Flux:	 3.0e-12 +/- 1.1e-12 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  3XMM J123113.1+120307 in the XMM-NEWTON/XMMSSC
catalogue
    Separation:  6.8" from the XRT source
    Cat Rate:	 5.4e-01 +/- 5.9e-03 ct/sec (0.3-10 keV)
    Cat Flux:	 5.7e-12 +/- 6.2e-14 erg cm^-2 s^-1 (0.3-10 keV)
       So the source is not significantly above the catalogued flux
    There is no evidence for fading
    NOTE: this source is not within 200 kpc of a GWGC galaxy.
    A SIMBAD object `2MASX J12311311+1203075' is 6.7" away
    There is 1 2MASS object within the source's 3-sigma error radius
  
  Source 32:
  =============
    RA: 	 187.7473 ( = 12h 30m 59.35s)  J2000
    Dec:	 +12.1925 ( = +12d 11' 33.0")  J2000
    Error:	 +5.6 (radius, 90% confidence).
    Peak Rate:	 -1.0e+00 +/- -1.0e+00 ct/sec (0.3-10 keV)
    Peak Flux:	 -4.3e-11 +/- -4.3e-11 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  3XMM J123059.4+121131 in the XMM-NEWTON/XMMSSC
catalogue
    Separation:  1.8" from the XRT source
    Cat Rate:	 7.5e-01 +/- 9.4e-03 ct/sec (0.3-10 keV)
    Cat Flux:	 7.9e-12 +/- 9.9e-14 erg cm^-2 s^-1 (0.3-10 keV)
       So the source is not significantly above the catalogued flux
    There is no evidence for fading
    NOTE: this source is not within 200 kpc of a GWGC galaxy.
    A SIMBAD object `2XMM J123059.4+121131' is 2.7" away

This circular is an official product of the Swift team.

GCN Circular 18744

Subject

LIGO/Virgo G211117: DESGW program observations with DECam

Date

2015-12-29T04:16:09Z (10 years ago)

From

M. Soares-Santos at Fermi Lab <marcelle.soares.santos@gmail.com>

M. Soares-Santos (Fermilab), A. Rest (STSCI), D. James (CTIO/NOAO), D. J.
Brout (UPenn), J. Annis (Fermilab), E. Berger (Harvard), H.-Y. Chen
(UChicago), P. Cowperthwaite (Harvard), H. T. Diehl (Fermilab), B. Farr
(UChicago), D. A. Finley (Fermilab), J. Frieman (Fermilab/UChicago),  R.
Gruendl (NCSA), D. Holz (UChicago), R. Kessler (UChicago), K. Herner
(Fermilab), E. Neilsen (Fermilab), M. Sako (UPenn), B. Yanny (Fermilab)

On behalf of the DESGW team:

We report on observations done with the Dark Energy camera (DECam) on the
Blanco 4-m telescope at CTIO on the night of 2015-12-27 in response to the
LVC trigger G211117/G211182. These observations are part of a plan to
observe about 90 sq-deg of the region of interest (the subregion that is
visible from CTIO) and cover a total of about 10% of the total LVC
probability.

DECam has a 3 sq-deg field of view, and typically reaches i,z = 23rd
limiting
magnitudes for 90 sec exposure times. If an optical counterpart of
magnitude ~23 or brighter, is present within the imaged area, our observing
strategy allows us to achieve ~90% detection probability.

Coordinates observed in the first night are given below. More observations
are planned for upcoming nights. Analysis is underway.

ra      dec
29.932371       2.0517
25.168446       -3.0207
26.75595        -2.0063
37.708542       13.20445
34.568587       9.14855
23.617796       -6.0642

-- 
Marcelle Soares-Santos
http://home.fnal.gov/~marcelle/
http://www.darkenergysurvey.org/ <http://darkenergysurvey.org/>

GCN Circular 18742

Subject

LIGO/Virgo G211117: Optical NIR observation with Kanata telescope

Date

2015-12-29T01:56:22Z (10 years ago)

From

Michitoshi Yoshida at J-GEM <yoshidam@hiroshima-u.ac.jp>

R. Itoh, Y. Kanda, M. Yoshida, Y. Utsumi, K. S. Kawabata, M. Uemura,
T. Nakaoka, M. Kawabata (HASC, Hiroshima Univ.), M. Tanaka (NAOJ)
on behalf of J-GEM collaboration

We observed nearby galaxies listed in GWGC in the error area of
the G211117 with HONIR (7 arcmin FOV optical near-infrared 2 color
simultaneous imager & spectrograph) attached to the 1.5m Kanata
telescope on 2015-12-28 (UTC). We performed I and J bands imaging
observations.

We found a transient point source in the field of UGC 1410 at
2015-12-28 13:42 (UTC). The object was clearly detected both in I
and J. The position and I band magnitude of this object are

      RA 01:56:17.6   DEC +04:33:08   17.3 $B!^(B 0.2 (I).

The position is consistent with that of the SDSS J015617.19+043307.7
whose i band magnitude is 22.12 (SDSS DR10). The OT we found is about
100 times brighter than this SDSS object. Spectroscopic follow-up
is encouraged.

The observed galaxies and the 3-sigma I-band limiting magnitudes are
listed below.

#Time(UT) exposure ra[deg.] width[arcrmin] dec[deg.] width[arcmin]
#I-Upperlimit(3-sigma) Object
#-----------------------------------------------------------------
2015-12-28T09:00:44 120.0 31.1792 7 8.5431 7 19.4 UGC01572
2015-12-28T09:14:04 120.0 29.5250 7 5.7689 7 20.7 PGC1288823
2015-12-28T09:27:33 120.0 34.4042 7 12.5089 7 -- IC1790
2015-12-28T09:41:06 120.0 35.3792 7 14.1986 7 19.0 UGC01817
2015-12-28T09:55:28 120.0 32.2758 7 1.6333 7 19.8 J020905.98+013800.5
2015-12-28T10:35:37 120.0 38.7912 7 20.8525 7 20.6 UGC02064
2015-12-28T10:49:12 120.0 26.9542 7 0.3039 7 -- PGC1146688
2015-12-28T11:02:32 120.0 26.7250 7 0.6139 7 -- PGC1138988
2015-12-28T11:28:11 120.0 28.6708 7 0.6114 7 -- PGC1170628
2015-12-28T11:42:03 120.0 45.5333 7 29.1081 7 20.7 UGC02497
2015-12-28T11:55:44 120.0 27.8500 7 1.6961 7 19.8 PGC1202981
2015-12-28T12:09:06 120.0 29.5167 7 2.0436 7 -- [RGK2003]J015804.70+020237.4
2015-12-28T12:22:23 120.0 29.4083 7 2.4231 7 20.8 PGC007383
2015-12-28T12:35:42 120.0 29.0542 7 3.4886 7 19.4 PGC007248
2015-12-28T12:49:00 120.0 29.6417 7 3.2569 7 20.1 UGC01454
2015-12-28T13:02:16 120.0 29.5083 7 3.3692 7 17.6 UGC01446
2015-12-28T13:15:30 120.0 29.5042 7 3.4539 7 19.9 PGC007442
2015-12-28T13:28:45 120.0 29.0667 7 3.7617 7 19.9 IC0174
2015-12-28T13:42:06 120.0 29.0667 7 4.6469 7 21.0 UGC01410
2015-12-28T14:00:13 120.0 29.4958 7 4.3950 7 19.9 UGC01444
2015-12-28T14:13:38 120.0 29.2833 7 4.5644 7 20.9 PGC007331
2015-12-28T14:26:52 120.0 29.0250 7 4.9969 7 20.6 PGC007225
2015-12-28T14:40:08 120.0 29.1375 7 5.2150 7 19.2 PGC007276
2015-12-28T14:53:20 120.0 29.7083 7 5.3597 7 17.3 PGC007476
2015-12-28T15:06:35 120.0 29.7208 7 5.4175 7 19.8 PGC007477
2015-12-28T15:19:58 120.0 30.8958 7 4.7856 7 17.3 UGC01553
2015-12-28T15:50:04 120.0 38.1708 7 15.7192 7 20.7 PGC089526
2015-12-28T16:03:20 120.0 40.2500 7 17.4311 7 19.1 UGC02168
2015-12-28T16:16:55 120.0 38.2208 7 19.2581 7 -- PGC009699
2015-12-28T16:30:12 120.0 39.7667 7 18.3939 7 17.7 PGC010042
2015-12-28T16:43:30 120.0 42.3125 7 21.3047 7 --- PGC089527
2015-12-28T16:56:49 120.0 43.8000 7 24.6347 7 19.0 PGC011015
2015-12-28T17:10:05 120.0 45.5167 7 25.7933 7 17.8 PGC090653
2015-12-28T17:23:33 120.0 52.8250 7 35.4661 7 19.6 UGC02770
2015-12-28T17:36:47 120.0 53.2083 7 36.2186 7 19.5 UGC02778
2015-12-28T17:50:10 120.0 53.3042 7 36.1842 7 17.7 UGC02780
2015-12-28T18:03:31 120.0 55.3833 7 37.2256 7 17.7 UGC02817
2015-12-28T18:16:48 120.0 56.7417 7 38.6342 7 18.4 UGC02857
2015-12-28T18:30:12 120.0 57.7208 7 39.7889 7 18.1 PGC097021
2015-12-28T19:01:50 120.0 70.3417 7 45.8281 7 18.6 PGC3094748
2015-12-28T19:15:12 120.0 68.9917 7 47.7172 7 19.3 PGC3094741
2015-12-28T19:28:31 120.0 69.5625 7 48.6942 7 19.3 PGC015704
2015-12-28T19:41:56 120.0 76.5833 7 50.8417 7 20.9 PGC097073
2015-12-28T19:55:20 120.0 84.9333 7 52.6019 7 19.8 PGC2816495
2015-12-28T20:08:46 120.0 84.4417 7 54.1625 7 17.3 PGC090015
2015-12-28T20:22:13 120.0 92.7792 7 55.3381 7 -- PGC090750
2015-12-28T20:35:34 120.0 103.2917 7 57.1778 7 17.9 UGC03574
2015-12-28T20:48:56 120.0 105.9958 7 56.4861 7 20.1 PGC020086

GCN Circular 18741

Subject

LIGO/Virgo G211117: Fermi GBM Observations

Date

2015-12-29T01:26:08Z (10 years ago)

From

E. Burns at U of Alabama/Huntsville <eb0016@uah.edu>

Eric Burns (UAH), Lindy Blackburn (CfA), Michael S. Briggs (UAH), Jordan
Camp (NASA/GSFC),
Nelson Christensen (Carleton College), Valerie Connaughton(USRA), Tito Dal
Canton (MPG),
Adam Goldstein (NASA/MSFC), Peter Jenke (UAH), Tyson Littenberg (USRA/UAH),
Judith Racusin (NASA/GSFC), Peter Shawhan (UMD), Leo Singer (NASA/GSFC),
John Veitch (Birmingham), Binbin Zhang (UAH)

The high probability northern arc of the Advanced LIGO skymap was mostly
occulted by the
Earth. The entire high probability southern arc was observed by Fermi GBM
during the GW
event. GBM was observing 45% of the cWB map probability.

A seeded search of the GBM Time-Tagged Event data between 8 keV and 40 MeV
from 30 s
before to 30 s after the CBC candidate event revealed no significant
emission on search
timescales in factors of 2 from 64 ms to 2.048 s. Additional blind searches
of the GBM NaI
detector data over several thousands of seconds before and after the CBC
candidate also
find no significant gamma-ray signal.

GCN Circular 18740

Subject

LIGO/Virgo G211117: Optical follow-up with Kanata telescope

Date

2015-12-29T01:05:29Z (10 years ago)

From

Michitoshi Yoshida at J-GEM <yoshidam@hiroshima-u.ac.jp>

R. Itoh, Y. Utsumi, T. Nakaoka, M. Kawabata, M. Yoshida (HASC,
Hiroshima Univ.) on behalf of J-GEM collaboration

We observed nearby galaxies listed in GWGC in the error area of
the G211117 with HOWPol (15 arcmin FOV optical imager) attached
to the 1.5m Kanata telescope on 2015-12-27 (UTC). We performed
R and I bands imaging observations. No optical transient brighter
the upper limits of the observed fields was detected in both
bands. The observed objects and 3-sigma upper limits are listed
below.

#Time(UT) exposure[sec] ra[deg.] width[arcrmin] dec[deg.]
#width[arcmin] R-Upperlimit(3-sigma) I-Upperlimit(3-sigma) Object
#-----------------------------------------------------------------
2015-12-27T18:10:18 90.0 57.7208 10 39.7889 10 19.2 19.2 PGC097021
2015-12-27T18:30:56 90.0 49.2417 10 31.5672 10 17.6 17.7 UGC02627
2015-12-27T18:38:03 90.0 52.8250 10 35.4661 10 18.2 17.9 UGC02770
2015-12-27T18:48:39 90.0 53.3042 10 36.1842 10 18.3 18.0 UGC02780
2015-12-27T18:59:12 90.0 53.6958 10 36.2097 10 18.6 18.6 UGC02788
2015-12-27T19:09:49 90.0 55.3833 10 37.2256 10 17.8 18.2 UGC02817
2015-12-27T19:20:21 90.0 57.0375 10 37.4569 10 17.8 17.7 PGC165376
2015-12-27T19:31:01 90.0 58.2333 10 40.1125 10 18.8 18.9 PGC097023
2015-12-27T19:42:15 90.0 207.9833 10 -29.7647 10 18.2 18.2 PGC725406
2015-12-27T19:57:26 90.0 208.1917 10 -29.9297 10 18.4 18.4 ESO445-065
2015-12-27T20:07:55 90.0 208.4333 10 -30.5281 10 18.5 18.6 PGC089791
2015-12-27T20:18:23 90.0 208.5958 10 -30.3797 10 18.4 18.4 PGC089797
2015-12-27T20:29:00 90.0 208.3292 10 -30.6975 10 18.4 18.5 PGC714066
2015-12-27T20:39:39 90.0 208.4833 10 -30.9794 10 18.7 18.7 PGC089792
2015-12-27T20:50:13 90.0 208.5875 10 -31.1817 10 19.0 18.8 PGC184225
2015-12-27T21:00:47 90.0 208.6417 10 -31.4703 10 18.6 18.7 PGC089799
2015-12-27T21:11:22 90.0 209.6125 10 -31.7761 10 18.2 17.7 ESO445-085
2015-12-27T21:21:57 90.0 209.1333 10 -32.4886 10 16.5 -- PGC690995

GCN Circular 18738

Subject

LIGO/Virgo G211117: MASTER Observations and Inspection + OT

Date

2015-12-28T19:05:25Z (10 years ago)

From

Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov2007@gmail.com>

V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov 
Lomonosov Moscow State University, Sternberg Astronomical Institute

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

R. Rebolo, M. Serra-Ricart, G. Israelian, N.Lodiu
The Instituto de Astrofisica de Canarias

A. Tlatov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory

O. Gress, K. Ivanov, N.M. Budnev
Irkutsk State University

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



MASTER-IAC  robotic telescope (MASTER-Net: http://observ.pereplet.ru, 2x4 
square degrees) located in IAC was pointed to the  LIGO/Virgo G211117 event 
(Possible Gravitational Wave Burst)  7975 sec after notice time and
1 days 58376 sec after trigger time at 2015-12-27 19:51:49 UT. Our first 
(180s exposure)  set we have 5-sigma upper limit has been about 20.0 mag 
(unfiltered).

MASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru) 
located in SAAO was pointed to the LIGO/Virgo G211117 event 19726 sec 
after notice time and 1 days 70127 sec after trigger time at 2015-12-27 23:07:40 UT. On 
our first (180s exposure)  set we haven`t found optical transient  within 
LIGO error-box (ra=02 31 59 dec=+07 59 59 r=0.100000).
The 5-sigma upper limit has been about 20.2mag (unfiltered).
The message may be cited.


MASTER-Kislovodsk  robotic telescope (MASTER-Net: 
http://observ.pereplet.ru) located in SAAO was pointed to the  LIGO/Virgo 
G211117 event
9608 sec after notice time and 1 days 60009 sec after trigger time at 
2015-12-27 20:19:02 UT. On our first (180s exposure)  set we have
5-sigma upper about 15.3mag (unfiltered).

The full Coverage map  starting after trigger (47.5 % total probability 
- north + south segment) is  available here:
http://master.sai.msu.ru/static/G211117_MASTER_NET.png
This map includes both independently MASTER survey of the alert area on 
26th after , and Inspect images after the notice time (2015-12-27 17:38)

Four MASTER VWF  (very wide field FOV = 2 x 386 sq. degree, d=82 mm f/1.2) 
cameras at Kislovodsk and Canary Island cover 4.3 % of total probability 
field synchronously with Ligo trigger at 2015-12-26 03:38:53 UTC.
I.e we have  a set of 5 seconds images before, during and after trigger 
without time gaps.

The 3 sigma upper limit is about 11 mag at a single (5 seconds) image and 
12 mag at a coadd of 12 images with total exposure 60 sec.

Coverage map available here: 
http://master.sai.msu.ru/static/G211117_WF.png

We detected second OT during inspection.

MASTER OT J124246.31+111448.6 - possible QSO in active state not relaited 
with gravitational wave event.

MASTER-IAC auto-detection system discovered OT source at (RA, Dec) = 12h 
42m 46.31s +11d 14m 48.6s on 2015-12-28.28271 UT (error box  1 arcsec).
The OT unfiltered magnitude is 18.9m (limit 19.5m).

The OT is seen in 3 images. There is no minor planet at this place.

We have reference image without OT on 2015-12-28.25404 UT with unfiltered 
magnitude limit 20.0 m.
There is possible QSO  SDSS 124246.25+111449.0 inside our error box.
We have long story of the avout 2 magnitude variability this sources in 
Tunka nad Kislovodsk  MASTERs DataBase.

The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/124246.31111448.6.png

The reduction is continuated. 
This circular is an official product of the MASTER team.

GCN Circular 18737

Subject

LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event

Date

2015-12-28T17:36:51Z (10 years ago)

From

Volodymyr Savchenko at APC,Paris <savchenk@apc.in2p3.fr>

V. Savchenko (APC, Paris, France), S. Mereghetti (IASF-Mi, Italy),
C. Ferrigno, E. Bozzo (ISDC, University of Geneva, CH) ,
E. Kuulkers (ESAC/ESA, Madrid, Spain), on behalf of a larger collaboration

The INTEGRAL spacecraft has a highly elliptical orbit and the instruments
are switched off around the perigee passage, every 2.6 days, to prevent
radiation induced damages. Unfortunately, at the time of the LIGO/Virgo
trigger G211117 (2015-12-26 03:38:53 UTC) the spacecraft was close
to the perigee between the orbits number 1625 and 1626. The data
from the anti-coincidence monitor are not available from 2015-12-25 20:57
to 2015-12-26 07:46 UTC. Yet, the narrow-field hard X-ray instruments
of INTEGRAL were pointing to the Cygnus region when the operations
resumed at 2015-12-26 07:59  (about 4.5 hours after the trigger), too far
from the trigger high probability zones to yield any meaningful limit on 
possible
long-lasting electromagnetic counterparts of the gravitational wave 
trigger.

GCN Circular 18735

Subject

LIGO/Virgo G211117: Pan-STARRS1 observations 2015-12-28

Date

2015-12-28T16:05:20Z (10 years ago)

From

S. J. Smartt at Queens U Belfast <s.smartt@qub.ac.uk>

K. C. Chambers, A. Schulz (IfA, University of Hawaii), D. Young, K. Smith, 
S. Smartt (Queen���s University Belfast),  M. Coughlin (Harvard), L. Denneau, 
H. Flewelling, A. Heinze, M. E. Huber, E. A. Magnier, N. Primak, A. Rest (STScI),  
A. Sherstyuk (IfA), B. Stalder (IfA), C. W. Stubbs (Harvard) J. Tonry, 
C. Waters (IfA), D. Wright, (QUB)

We report the observations of northern arc of the skymap defined by the 
BAYESTAR pipeline as reported GCN18728Loading...
 
   with the Pan-STARRS1 telescope
(2.9 degree diameter FOV). 

We have mapped the arc from the southern point of RA=34.1174 DEC=10.129 
through to the northern tip at RA=86.394 DEC=53.6, corresponding 
to most of the 30% enclosed region in the northern arc of the BAYESTAR map. 

Observations were taken in the PS1 i-band (Tonry et al. 2012, ApJ 750, 99)
and at each pointing position a dithered sequence of 4 x 45 sec was taken, 
which will be combined as a single epoch stack. These dithered sequences
were repeated, with overlaps, to map the 30% region contiguously.  
A total of 371 individual 45 sec images were taken. 

Data taking began at  2015-12-28 05:07:49 and finished 2015-12-28 13:33:07
(UTC). 

The images are currently being differenced with respect to the Pan-STARRS
3Pi all sky i-band image (see Magnier et al. 2013, ApJS 205, 20 ; 
Huber et al. 2015,  ATel 7153) to detect transient objects. Further observations
of the region are planned as weather allows.

GCN Circular 18734

Subject

LIGO/Virgo G211117: INAF VST-ESO PARANAL observations

Date

2015-12-28T15:21:17Z (10 years ago)

From

Enzo Brocato at INAF-OA Roma <enzo.brocato@oa-roma.inaf.it>

A.Grado (INAF-OAC), G.Greco (Urbino University/INFN Firenze), E. Brocato (INAF-OAR), M. Branchesi (Urbino University/INFN Firenze), E. Cappellaro (INAF-OAPd),  L.Amati (INAF-IASF Bo), L. A. Antonelli, (INAF-OAR), P. Astone (INFN-Roma), S. Campana, S. Covino, P. D'Avanzo (INAF-OAB),  V. D'Elia (INAF-ASDC), F. Getman (INAF-OAC), G. Giuffrida (INAF-ASDC), L. Limatola (INAF-OAC), M. Lisi (INAF-OAR), S. Marinoni, P. Marrese (INAF-ASDC), A. Melandri (INAF-OAB), L. Nicastro, E. Palazzi (INAF-IAFS Bo), E. Pian (SNS-Pisa), S. Piranomonte, L. Pulone (INAF-OAR), F. Ricci (Sapienza University), G. Stratta (Urbino University/INFN Firenze), G. Tagliaferri (INAF-OAB), V. Testa (INAF-OAR), L. Tomasella (INAF-OAPd) on behalf of the INAF Gravitational Astronomy group report: 

We observed 72 square degree of the skymap of the advanced LIGO and Virgo trigger G211117, with the VLT Survey Telescope (VST) at ESO-Paranal equipped with OMEGACAM (FOV=1 square degree). The r SDSS filter was used. 
The observations are divided in 8 regions 3 x 3 square degree each, centered on the following coordinates RA, Dec (J2000):

North
02:29:55.200 +16:13:12.00
02:38:02.208 +19:13:12.00
02:46:35.712 +22:12:33.84
02:59:40.800 +25:13:12.00
03:06:55.128 +28:13:12.00
03:18:23.712 +31:13:12.00
South
13:45:53.208 -26:48:00.00
13:39:47.208 -23:48:00.00

The first group of observations on the North area started at 2015-12-28T01:14:02.794 UT and finished at 2015-12-28T04:00:48.959 UT, while the observations in the South area started at 2015-12-28T07:51:18.143 UT and finished at 2015-12-28T08:55:27.653 UT. 
The image analysis is ongoing. Further observations of these fields are planned.

GCN Circular 18733

Subject

LIGO/Virgo G211117: Further Swift-XRT sources

Date

2015-12-28T13:04:39Z (10 years ago)

From

Phil Evans at U of Leicester <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), J.A. Kennea (PSU), Scott Barthelmy
(NASA/GSFC), Dave Burrows (PSU), Sergio Campana (INAF-OAB), Brad Cenko
(NASA/GSFC), Neil Gehrels (NASA/GSFC), Paolo Giommi (ASI), Frank
Marshall (NASA/GSFC), John Nousek (PSU), Paul O'Brien (U. Leicester),
Julian Osborne (U. Leicester), Kim Page (U. Leicester), David Palmer
(LANL), Matteo Perri (ASDC), Judy Racusin (NASA/GSFC), Mike Siegel
(PSU), Gianpiero
Tagliaferri (INAF-OAB) report on behalf of the Swift team:

Further Swift observations have been downlinked. The observations
currently span from 140 ks to 164 ks after the aLIGO trigger, and cover

2.8 sq degrees on the sky (corrected for overlaps), and are ongoing.

Since the last Swift GCN, we have detected 3 extra X-ray sources, these
are. Each source is assigned a rank of 1-4 which describes
how likely it is to be related to the GW trigger, with 1 being the most

likely and 4 being the least likely. The ranks are described at
http://www.swift.ac.uk/ranks.php.

We have found:

* 0 sources of rank 1
* 0 sources of rank 2
* 3 sources of rank 3
* 0 sources of rank 4

We assumed a power-law spectrum with NH=3e20 cm^2, and Gamma=1.7


RANK 3 sources
==============

These are uncatalogued X-ray sources, however they are not brighter
than previous upper limits, so do not stand out as likely counterparts
to the GW trigger.

Source 3:
=============
RA: 202.5552 ( = 13h 30m 13.25s) J2000
Dec: -20.9046 ( = -20d 54' 16.6") J2000
Error: +5.3 (radius, 90% confidence).
Peak Rate: 9.6e-03 +/- 5.2e-03 ct/sec (0.3-10 keV)
Peak Flux: 4.1e-13 +/- 2.2e-13 erg cm^-2 s^-1 (0.3-10 keV)
1SXPS UL: 1.2e-03 ct/sec, (0.3-10 keV)
So the source is not significantly above the 1SXPS 3-sigma limit
RASS UL: 5.1e-02 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)
So the source is not significantly above the RASS 3-sigma limit
There is no evidence for fading
NOTE: this source is not within 200 kpc of a GWGC galaxy.
There is 1 2MASS object within the source's 3-sigma error radius

Source 4:
=============
RA: 202.5674 ( = 13h 30m 16.18s) J2000
Dec: -20.9240 ( = -20d 55' 26.4") J2000
Error: +5.5 (radius, 90% confidence).
Peak Rate: 1.5e-02 +/- 6.5e-03 ct/sec (0.3-10 keV)
Peak Flux: 6.6e-13 +/- 2.8e-13 erg cm^-2 s^-1 (0.3-10 keV)
1SXPS UL: 1.2e-03 ct/sec, (0.3-10 keV)
So the source is not significantly above the 1SXPS 3-sigma limit
RASS UL: 5.2e-02 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)
So the source is not significantly above the RASS 3-sigma limit
There is no evidence for fading
NOTE: this source is not within 200 kpc of a GWGC galaxy.
There is 1 2MASS object within the source's 3-sigma error radius

Source 5:
=============
RA: 202.3542 ( = 13h 29m 25.01s) J2000
Dec: -21.2270 ( = -21d 13' 37.2") J2000
Error: +5.7 (radius, 90% confidence).
Peak Rate: 2.7e-02 +/- 8.4e-03 ct/sec (0.3-10 keV)
Peak Flux: 1.1e-12 +/- 3.6e-13 erg cm^-2 s^-1 (0.3-10 keV)
RASS UL: 2.5e-02 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)
So the source is not significantly above the RASS 3-sigma limit
There is no evidence for fading
NOTE: this source is not within 200 kpc of a GWGC galaxy.

This circular is an official product of the Swift team.

GCN Circular 18732

Subject

LIGO/Virgo G211117: Swift-XRT sources

Date

2015-12-28T12:45:47Z (10 years ago)

From

Phil Evans at U of Leicester <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), J.A. Kennea (PSU), Scott Barthelmy
(NASA/GSFC), Dave Burrows (PSU), Sergio Campana (INAF-OAB), Brad Cenko
(NASA/GSFC), Neil Gehrels (NASA/GSFC), Paolo Giommi (ASI), Frank
Marshall (NASA/GSFC), John Nousek (PSU), Paul O'Brien (U. Leicester),
Julian Osborne (U. Leicester), Kim Page (U. Leicester), David Palmer
(LANL), Matteo Perri (ASDC), Judy Racusin (NASA/GSFC), Mike Siegel
(PSU), Gianpiero Tagliaferri (INAF-OAB) report on behalf of the Swift
team:

Swift has performed a series of 24 observations of galaxies (from the
GWGC catalogue) within the aLIGO error region for the aLIGO trigger
G211117, using the 'bayestar' GW localisation map. The observations
currently span from 140 ks to 164 ks after the aLIGO trigger, and cover
2.8 sq degrees on the sky (corrected for overlaps). Further
observations are ongoing.

We have detected 2 X-ray sources. Each source is assigned a rank of 1-4
which describes how likely it is to be related to the GW trigger, with
1 being the most likely and 4 being the least likely. The ranks are
described at http://www.swift.ac.uk/ranks.php.

We have found:

  * 0 sources of rank 1
  * 0 sources of rank 2
  * 0 sources of rank 3
  * 2 sources of rank 4

We assumed a power-law spectrum with NH=3e20 cm^2, and Gamma=1.7

RANK 4 sources
==============

These are catalogued X-ray sources, showing no signs of outburst
compared to previous observations, so they are not likely to be related
to the GW trigger.
  
  Source 1:
  =============
    RA: 	 207.3302 ( = 13h 49m 19.25s)  J2000
    Dec:	 -30.3100 ( = -30d 18' 36.0")  J2000
    Error:	 +4.1 (radius, 90% confidence).
    Peak Rate:	 1.0e+00 +/- 2.4e-01 ct/sec (0.3-10 keV)
    Peak Flux:	 4.4e-11 +/- 1.0e-11 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  1SXPS J134919.2-301834 in the 1SXPS catalogue
    Separation:  1.5" from the XRT source
    Cat Rate:	 2.6e+00 +/- 2.6e-02 ct/sec (0.3-10 keV)
    Cat Flux:	 1.1e-10 +/- 1.1e-12 erg cm^-2 s^-1 (0.3-10 keV)
       So the source is not above the catalogued flux
    There is no evidence for fading
    There is 1 GWGC galaxy within 200 kpc of the source.
    A SIMBAD object `RXC J1349.3-3018' is 2.1" away
    There are 3 2MASS objects within the source's 3-sigma error radius
  
  Source 2:
  =============
    RA: 	 202.5292 ( = 13h 30m 7.01s)  J2000
    Dec:	 -21.6998 ( = -21d 41' 59.3")  J2000
    Error:	 +5.2 (radius, 90% confidence).
    Peak Rate:	 6.2e-02 +/- 1.5e-02 ct/sec (0.3-10 keV)
    Peak Flux:	 2.7e-12 +/- 6.3e-13 erg cm^-2 s^-1 (0.3-10 keV)
    Cat Source:  1RXS J133006.8-214156 in the ROSAT/RASSFSC catalogue
    Separation:  3.9" from the XRT source
    Cat Rate:	 8.3e-02 +/- 2.4e-02 ct/sec (0.3-10 keV)
    Cat Flux:	 2.3e-12 +/- 6.9e-13 erg cm^-2 s^-1 (0.3-10 keV)
       So the source  is 0.3-sigma above the catalogued flux
    There is no evidence for fading
    NOTE: this source is not within 200 kpc of a GWGC galaxy.
    A SIMBAD object `[RKV2003] QSO J1330-2142 abs 0.3014' is 2.9" away
    There is 1 2MASS object within the source's 3-sigma error radius

This circular is an official product of the Swift team.

GCN Circular 18730

Subject

LIGO/Virgo G211117: SWASP optical observations

Date

2015-12-27T23:05:46Z (10 years ago)

From

Danny Steeghs at U of Warwick/GOTO <D.T.H.Steeghs@warwick.ac.uk>

D.Steeghs, D.Pollacco, D.Galloway, G.Ramsay, V.Dhillon & P.O'Brien on behalf of the GOTO consortium report:


Following GCN #18728Loading...
 
 , the SuperWASP Exoplanet camera on La Palma started imaging the error regions containing G211117/G211182 at 19:17 UT Dec 27 2015. The camera array has already mapped the northern lobe of the reported LIGO/VIRGO skymap 10 times over a 3.5 hr period to a depth of around V~16th. Observations are continuing.

GCN Circular 18729

Subject

LIGO/Virgo G211117: MASTER possible OT detection at the begining of inspection

Date

2015-12-27T23:04:02Z (10 years ago)

From

Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov2007@gmail.com>

V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov,
O.Gress
Lomonosov Moscow State University, Sternberg Astronomical Institute

D.Buckley
South African Astronomical Observatory


MASTER OT J020906.21+013800.1  - possible OT in PGC Galaxy.

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 02h
09m 06.21s +01d 38m 00.1s on 2015-12-27.85448 UT.
The OT unfiltered magnitude is 18.3m (limit 20.0m).

The OT is seen in 6 images. There is no minor planet at this place.
There is PGC1200980 galaxy (it seems spiral galaxy and distance about 100
Mpc)  very close to OT. The OT offset are  4.3E   1.5S  arcsec.

We have reference image without OT on 2015-06-07.17962 UT with unfiltered
magnitude limit 18.9m.

Spectral observations are required.

The discovery and reference images are available at:

http://master.sai.msu.ru/static/OT/020906.21013800.1.png

This circular can be cited.
-- 
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http:www.pereplet.ru/avtori/lipunov.html

The Principal Investigator of MASTER Global Robotic Net
http://observ.pereplet.ru
Professor of Lomonosov Moscow State University Physics Department,
The Head of Space monitoring laboratory of Sternberg Astronomical Institute
of Lomonosov MSU

GCN Circular 18728

Subject

LIGO/Virgo G211117: Identification of a GW CBC Candidate

Date

2015-12-27T17:39:45Z (10 years ago)

From

Leo Singer at NASA/GSFC <leo.p.singer@nasa.gov>

The LIGO Scientific Collaboration and Virgo report:

The online gstlal CBC analysis, which is sensitive to binary coalescence
events from systems containing neutron stars and/or black holes,
identified candidate G211117 during real-time processing of data from
LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) at
2015-12-26 03:38:53.648 UTC (GPS time: 1135136350.648).

The candidate was identified by an expanded low-latency pipeline
configuration that is sensitive to stellar-mass BNS, NSBH, and BBH
mergers. G211117 is an event of interest because its false alarm rate, as
determined by the online analysis, passed our stated alert threshold of
~1/month. The event's properties can be found at this URL:

https://gracedb.ligo.org/events/G211117

If confirmed as astrophysical, the system contains at least one and most
likely two black holes.

The candidate was below the threshold for detection by the low-latency
un-modeled burst searches. However, manual offline analysis with Coherent
WaveBurst (cWB) recovered a candidate with consistent timing and
amplitude, designated G211182:

https://gracedb.ligo.org/events/G211182

Two sky maps are available at this time and can be retrieved from the
GraceDB event pages:

 * bayestar.fits.gz, an initial localization generated by the BAYESTAR
   pipeline based on the CBC analysis about 2 minutes after the event. The
   probability is concentrated in two long, thin arcs. The 50% credible
   region spans about 430 deg2 and the 90% region about 1400 deg2. This is
   the preferred sky map at this time.

 * skyprobcc_cwb.fits, generated from the cWB offline analysis about six
   hours after the event. The area supported by this sky map is
   qualitatively very similar to and essentially a superset of the
   BAYESTAR sky map, with a 90% credible area of 2200 deg2.