LIGO/Virgo S190517h

The LIGO Scientific Collaboration and the Virgo Collaboration report:

We identified the compact binary merger candidate S190517h during
real-time processing of data from LIGO Hanford Observatory (H1), LIGO
Livingston Observatory (L1), and Virgo Observatory (V1) at 2019-05-17
05:51:01.831 UTC (GPS time: 1242107479.831). The candidate was found
by the GstLAL [1], CWB [2], MBTAOnline [3], PyCBC Live [4], and SPIIR
[5] analysis pipelines.

S190517h is an event of interest because its false alarm rate, as
estimated by the online analysis, is 2.4e-09 Hz, or about one in 13
years. The event's properties can be found at this URL:

https://gracedb.ligo.org/superevents/S190517h

The classification of the GW signal, in order of descending
probability, is BBH (98%), MassGap (2%), NSBH (<1%), Terrestrial
(<1%), or BNS (<1%).

Assuming the candidate is astrophysical in origin, there is strong
evidence against the lighter compact object having a mass < 3 solar
masses (HasNS: <1%). Using the masses and spins inferred from the
signal, there is strong evidence against matter outside the final
compact object (HasRemnant: <1%).

One skymap is available at this time and can be retrieved from the
GraceDB event page:
 * bayestar.fits.gz, an updated localization generated by BAYESTAR
[6], distributed via GCN notice about 35 minutes after the candidate

For the bayestar.fits.gz skymap, the 90% credible region is 939
deg2. Marginalized over the whole sky, the a posteriori luminosity
distance estimate is 2950 +/- 1038 Mpc (a posteriori mean +/-
standard deviation).

For further information about analysis methodology and the contents
of this alert, refer to the LIGO/Virgo Public Alerts User Guide
<https://emfollow.docs.ligo.org/userguide/>.

 [1] Messick et al. PRD 95, 042001 (2017)
 [2] Klimenko et al. PRD 93, 042004 (2016)
 [3] Adams et al. CQG 33, 175012 (2016)
 [4] Nitz et al. PRD 98, 024050 (2018)
 [5] Qi Chu, PhD Thesis, The University of Western Australia (2017)
 [6] Singer & Price PRD 93, 024013 (2016)

M. Doyle (UCD, Dublin), Bozzo Enrico,
V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland)
J. Rodi (IAPS-Roma, Italy)
A. Coleiro (APC, France)
S. Mereghetti (INAF IASF-Milano, Italy)

on behalf of the INTEGRAL multi-messenger collaboration:
https://www.astro.unige.ch/cdci/integral-multimessenger-collaboration

Using INTEGRAL SPI-ACS (following Savchenko
et al. 2017, A&A 603, A46) we have
performed a search for a prompt gamma-ray counterpart of S190517h (GCN
24570
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 ).

At the time of the event (2019-05-17 05:51:01 UTC, hereafter T0),
INTEGRAL was operating in nominal mode. The peak of the event
localization probability was at an angle of 90 deg with respect to the
spacecraft pointing axis. This orientation implies strongly suppressed
(8.7% of optimal) response of ISGRI, strongly suppressed (19% of
optimal) response of IBIS/Veto, and somewhat suppressed (61% of
optimal) response of SPI-ACS.

The background within +/-300 seconds around the event was somewhat
unstable (excess variance 1.9).

We have performed a search for any impulsive events in INTEGRAL SPI-
ACS (as described in Savchenko et al. 2012, A&A 541A, 122S).

The real time pipeline has found a collection of weak excesses
in the vicinity of the event, the most prominent being at T0+37s with
a S/N of 5.4 at the timescale of 0.1s. Note that this pipeline excludes
the shortest 0.05s timescale since it is usually strongly polluted by CR
effects.

We note the presence of a short time-scale variance excess in the days before
the event, and advise caution in interpreting this signal as astrophysical.
Further analysis of local noise properties will be reported elsewhere.

We do not detect any secure significant counterparts and estimate a 3-sigma
upper limit on the 75-2000 keV fluence of 2.7e-07 erg/cm^2 for a burst
lasting less than 1 s with a characteristic short GRB spectrum (an
exponentially cut off power law with alpha=-0.5 and Ep=600 keV)
occurring at any time in the interval within 300 s around T0. For a
typical long GRB spectrum (Band function with alpha=-1, beta=-2.5, and
Ep=300 keV), the derived peak flux upper limit is ~2.3e-07 (1.1e-08)
erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range.

A. Ursi (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), G. Piano
(INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M.
Cardillo, C. Casentini (INAF/IAPS), F. Lucarelli, C. Pittori (SSDC, and
INAF/OAR) , A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna),
M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste),
report on behalf of the AGILE Team:

In response to the LIGO/Virgo GW event S190517h at T0 = 2019-05-17 05:51:01
(UT), a preliminary analysis of the AGILE MiniCALorimeter (MCAL) triggered
data found no event candidates within a time interval covering -/+ 15 sec
from the LIGO/Virgo T0.

At the T0, about 55% of the S190517h 90% c.l. localization region was
accessible to the AGILE MCAL. Three-sigma upper limits (ULs) are obtained
for a 1 s integration time at different celestial positions within the
accessible S190517h localization region, from a minimum of 1.62E-06 erg
cm^-2 to a maximum of 2.73E-06 erg cm^-2 (assuming as spectral model a
single power law with photon index 1.5).

The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the
energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.

The IceCube Collaboration (http://icecube.wisc.edu/) reports:

IceCube has performed a search for track-like muon neutrino events
consistent with the sky localization of S190517h in a time range of 1000
seconds centered on the alert event time (2019-05-17 05:42:41.831 UTC to 2019-05-17 05:59:21.831 UTC)
during which IceCube was collecting good quality data. One track-like event
is found in spatial coincidence with the 90% spatial containment region of
S190517h calculated from the map circulated in the preliminary notice. This
represents an overall p-value of 0.094 (1.32sigma) with respect
to the background only hypothesis. Properties of the coincident event are shown below.

 dt           ra           dec         Angular Uncertainty(deg)         pvalue
----------------------------------------------------------------------------------
336.32         290.80         -69.39                 3.65                0.096


dt = Time offset (sec) of track event with respect to GW trigger.
Angular uncertainty = Angular uncertainty of track event: the radius of a circle representing 90% CL containment by area.
Pvalue = the pvalue for this specific track event with respect to a background only hypothesis

The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica.
The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu

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-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) started inspect of the LIGO/Virgo S190517h errorbox  4170 sec after trigger time at 2019-05-17 07:00:31 UT, with upper limit up to  17.4 mag. The observations began at zenit distance = 89 deg. The sun  altitude  is -54.4 deg. 

The galactic latitude b = -60 deg., longitude l = 98 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/ligo_1.php?id=10399

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

    4261 | 2019-05-17 07:00:31 |         MASTER-OAFA | ( 15h 14m 28.08s , -47d 28m 08.13s) |   C |   180 | 16.8 |        
    4441 | 2019-05-17 07:00:31 |         MASTER-OAFA | ( 15h 14m 28.07s , -47d 28m 08.11s) |   C |   540 | 17.4 |  Coadd 
    4481 | 2019-05-17 07:04:11 |         MASTER-OAFA | ( 15h 14m 27.72s , -47d 28m 09.36s) |   C |   180 | 17.0 |        
    4701 | 2019-05-17 07:07:52 |         MASTER-OAFA | ( 15h 14m 27.53s , -47d 28m 09.79s) |   C |   180 | 17.0 |        
    4922 | 2019-05-17 07:11:33 |         MASTER-OAFA | ( 15h 14m 27.39s , -47d 28m 10.72s) |   C |   180 | 16.9 |        
    6740 | 2019-05-17 07:41:51 |         MASTER-OAFA | ( 14h 48m 20.72s , -49d 54m 38.81s) |   C |   180 | 16.9 |        
    6968 | 2019-05-17 07:45:38 |         MASTER-OAFA | ( 15h 13m 09.55s , -49d 54m 41.18s) |   C |   180 | 16.9 |        
    7196 | 2019-05-17 07:49:26 |         MASTER-OAFA | ( 15h 24m 59.77s , -47d 55m 15.79s) |   C |   180 | 16.9 |        
    7422 | 2019-05-17 07:53:12 |         MASTER-OAFA | ( 14h 48m 20.54s , -49d 54m 20.37s) |   C |   180 | 16.9 |        
    7651 | 2019-05-17 07:57:02 |         MASTER-OAFA | ( 15h  0m 44.50s , -49d 54m 30.72s) |   C |   180 | 16.1 |        
    7874 | 2019-05-17 08:00:45 |         MASTER-OAFA | ( 15h 13m 09.41s , -49d 55m 04.42s) |   C |   180 | 16.9 |        
    8098 | 2019-05-17 08:04:29 |         MASTER-OAFA | ( 15h 25m 36.21s , -49d 55m 18.67s) |   C |   180 | 17.0 |        
    8327 | 2019-05-17 08:08:17 |         MASTER-OAFA | ( 15h 25m 00.05s , -47d 55m 01.19s) |   C |   180 | 16.8 |        
    8552 | 2019-05-17 08:12:03 |         MASTER-OAFA | ( 15h 36m 54.64s , -47d 55m 15.41s) |   C |   180 | 16.7 |        
    8777 | 2019-05-17 08:15:48 |         MASTER-OAFA | ( 15h  0m 45.15s , -49d 54m 58.14s) |   C |   180 | 17.0 |        
    9003 | 2019-05-17 08:19:33 |         MASTER-OAFA | ( 15h 25m 36.87s , -49d 55m 22.76s) |   C |   180 | 17.1 |        
    9226 | 2019-05-17 08:23:17 |         MASTER-OAFA | ( 15h 36m 56.49s , -47d 55m 18.15s) |   C |   180 | 17.1 |        
    9456 | 2019-05-17 08:27:06 |         MASTER-OAFA | ( 15h 14m 01.25s , -45d 55m 15.14s) |   C |   180 | 17.0 |        
    9683 | 2019-05-17 08:30:53 |         MASTER-OAFA | ( 15h  1m 09.15s , -47d 54m 41.76s) |   C |   180 | 17.2 |        
    9908 | 2019-05-17 08:34:39 |         MASTER-OAFA | ( 15h 38m 01.47s , -49d 55m 38.67s) |   C |   180 | 17.1 |        
   10133 | 2019-05-17 08:38:23 |         MASTER-OAFA | ( 15h 14m 02.68s , -45d 55m 16.36s) |   C |   180 | 17.2 |        
   10357 | 2019-05-17 08:42:07 |         MASTER-OAFA | ( 15h 25m 32.78s , -45d 55m 07.66s) |   C |   180 | 16.8 |        
   10581 | 2019-05-17 08:45:52 |         MASTER-OAFA | ( 15h  1m 08.79s , -47d 54m 43.28s) |   C |   180 | 16.8 |        
   10806 | 2019-05-17 08:49:37 |         MASTER-OAFA | ( 15h 13m 04.55s , -47d 55m 15.01s) |   C |   180 | 16.1 |        
   11031 | 2019-05-17 08:53:22 |         MASTER-OAFA | ( 15h 38m 03.43s , -49d 55m 41.57s) |   C |   180 | 16.9 |        
   11258 | 2019-05-17 08:57:08 |         MASTER-OAFA | ( 15h 50m 29.26s , -49d 55m 37.66s) |   C |   180 | 17.4 |        
   11438 | 2019-05-17 08:57:08 |         MASTER-OAFA | ( 15h 50m 29.29s , -49d 55m 37.72s) |   C |   540 | 17.2 |  Coadd 
   11486 | 2019-05-17 09:00:56 |         MASTER-OAFA | ( 15h 25m 32.58s , -45d 55m 14.31s) |   C |   180 | 16.6 |        
   11735 | 2019-05-17 09:05:05 |         MASTER-OAFA | ( 15h 13m 10.46s , -47d 56m 37.59s) |   C |   180 | 16.6 |        
   11960 | 2019-05-17 09:08:50 |         MASTER-OAFA | ( 15h 50m 36.46s , -49d 57m 26.48s) |   C |   180 | 17.3 |        
   12188 | 2019-05-17 09:12:38 |         MASTER-OAFA | ( 15h 50m 36.09s , -49d 57m 03.51s) |   C |   180 | 17.3 |        
   12414 | 2019-05-17 09:16:24 |         MASTER-OAFA | ( 15h  4m 58.03s , -43d 56m 18.42s) |   C |   180 | 17.1 |        
   12645 | 2019-05-17 09:20:15 |         MASTER-OAFA | ( 15h 37m 08.48s , -45d 56m 39.84s) |   C |   180 | 17.0 |        
   12870 | 2019-05-17 09:24:00 |         MASTER-OAFA | ( 14h 51m 04.73s , -45d 55m 58.32s) |   C |   180 | 17.3 |        
   13093 | 2019-05-17 09:27:44 |         MASTER-OAFA | ( 15h  4m 58.43s , -43d 56m 16.89s) |   C |   180 | 17.3 |        
   13322 | 2019-05-17 09:31:32 |         MASTER-OAFA | ( 15h 16m 05.35s , -43d 56m 11.57s) |   C |   180 | 17.0 |        
   13551 | 2019-05-17 09:35:21 |         MASTER-OAFA | ( 15h 37m 06.19s , -45d 56m 38.86s) |   C |   180 | 16.9 |        
   13773 | 2019-05-17 09:39:04 |         MASTER-OAFA | ( 15h 48m 36.85s , -45d 57m 16.16s) |   C |   180 | 17.2 |        
   13999 | 2019-05-17 09:42:49 |         MASTER-OAFA | ( 14h 51m 05.07s , -45d 55m 54.19s) |   C |   180 | 17.1 |        
   14222 | 2019-05-17 09:46:33 |         MASTER-OAFA | ( 15h  2m 35.93s , -45d 55m 50.52s) |   C |   180 | 17.4 |        
   14446 | 2019-05-17 09:50:16 |         MASTER-OAFA | ( 15h  2m 34.29s , -45d 55m 50.41s) |   C |   180 | 17.4 |        
   14671 | 2019-05-17 09:54:02 |         MASTER-OAFA | ( 15h 16m 02.79s , -43d 56m 28.14s) |   C |   180 | 17.2 |        
   14896 | 2019-05-17 09:57:46 |         MASTER-OAFA | ( 15h 48m 37.65s , -45d 57m 16.20s) |   C |   180 | 17.2 |        
   15118 | 2019-05-17 10:01:28 |         MASTER-OAFA | ( 15h 48m 37.56s , -45d 56m 55.05s) |   C |   180 | 17.1 |        
   15345 | 2019-05-17 10:05:15 |         MASTER-OAFA | ( 15h  2m 33.40s , -45d 55m 46.66s) |   C |   180 | 17.3 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.

M. Sugizaki, N. Kawai (Tokyo Tech), H. Negoro (Nihon U.),
M. Serino, S. Sugita (AGU),
M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.),
S. Nakahira, T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN),
T. Sakamoto, H. Nishida, A. Yoshida (AGU),
Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.),
M. Shidatsu (Ehime U.),
M. Oeda, K. Shiraishi (Tokyo Tech),
S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai,
M. Tominaga (JAXA),
Y. Ueda, A. Tanimoto, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake
(Kyoto U.),
H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.),
M. Yamauchi, S. Iwahori, Y. Kurihara, K. Kurogi, K. Miike (Miyazaki U.),
T. Kawamuro (NAOJ),
K. Yamaoka (Nagoya U.),
Y. Kawakubo (LSU)

We examined the MAXI/GSC all-sky X-ray images (2-20 keV) obtained
in the orbit after the LVC trigger
S190517h at 2019-05-17 05:51:01.831 UTC (GCN 24570
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 ).

At the trigger time of S190517h, the high-voltage of MAXI/GSC was off,
and it was turned on at T0+70 sec (+1.2 min).
The one-orbit (92 min) scan of GSC covered 71% of the 90% credible region
of the bayestar sky-map.
One of the high-credible regions around RA=15h, Dec=-45deg., was missed
because it was in the direction to the ISS-rotation pole.

No significant new source was found in the error region with the one-orbit scan.
The 1-sigma averaged upper limit obtained from the scan was 20 mCrab
at 2-10 keV.

If you require information of X-ray flux by MAXI/GSC at specific coordinates,
please contact the submitter of this circular by email.

The HAWC Collaboration (https://www.hawc-observatory.org) reports:

The HAWC Collaboration performed a follow-up of the gravitational wave
trigger S190517h (GCN #24570
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 ). At the time of the trigger the HAWC
local zenith was oriented towards (RA, Dec) = (224.9 deg, 19.1 deg).
24% of the GW candidate sky location probability fell within our
observable field of view (0-45 deg zenith angle).

We performed a search for a short timescale emission using 6 sliding
time windows (dt = 0.3s, 1s, 3s, 10s, 30s and 100s), shifted forward
in time by 20% of their width. We searched the 95% probability
containment area in a timescale-dependent time period, from t0-5dt to
t0+10dt, where t0 is the time of the GW trigger.

No significant gamma-ray detection above the background was observed.

The sensitivity of this analysis is greatly dependent on zenith angle,
ranging from 19.8 deg to 45.0 deg for the area searched in this
analysis. The 5 sigma detection sensitivity to a 1s (100s) burst in the
80-800GeV energy range goes from 2.2e-6 erg/cm^2 to 1.1e-4 erg/cm^2
(1.2e-5 erg/cm^2 to 5.0e-4 erg/cm^2), depending on the zenith
angle.

HAWC is a TeV gamma ray water Cherenkov array located in the state of
Puebla, Mexico. It is sensitive to the energy range ~0.1-100TeV, and
monitors 2/3 of the sky every day with an instantaneous field-of-view
of ~2 sr.

A. Goldstein (USRA) reports on behalf of the Fermi-GBM Team and the
GBM-LIGO/Virgo group:

For S190517h, and using the initial BAYESTAR skymap, Fermi-GBM was
observing 28.2% of the localization probability at event time.
There was no Fermi-GBM onboard trigger around the event time of the
LIGO/Virgo detection of GW trigger S190517h (GCN 24570
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 ). An automated,
blind search for short gamma-ray bursts below the onboard triggering
threshold in Fermi-GBM also identified no counterpart candidates. The GBM
targeted search, the most sensitive, coherent search for GRB-like signals,
was run from +/-30 s around merger time, and also identified no counterpart
candidates.

Part of the LVC localization region is behind the Earth for Fermi,
located at RA = 270.7 and Dec = -6.7 with a radius of 67.5 degrees.
We therefore set upper limits on impulsive gamma-ray emission.  Using the
representative soft, normal, and hard GRB-like spectral templates described
in arXiv:1612.02395
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 , we set the following 3 sigma flux upper limits over
10-1000 keV, weighted by the remaining visible GW localization probability
(in units of erg/s/cm^2):

Timescale  soft     norm     hard
--------------------------------------
0.128 s:   1.9e-07  3.1e-07  5.8e-07
1.024 s:   5.4e-08  8.1e-08  1.9e-07
8.192 s:   9.3e-09  1.5e-08  6.4e-08

Assuming the median luminosity distance of ~2950 Mpc from the GW detection,
we estimate intrinsic luminosity upper limits of (0.2-3.1)E50 erg/s for the
soft template, (0.2-4.4)E50 erg/s for the normal template, and (1.5-14.)E50
erg/s for the hard template over the 1 keV-10 MeV energy range.

S. Xiao, C. Cai, Q. B. Yi, Q. Luo, C. K. Li, 
X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, 
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team: 

Insight-HXMT was taking data normally around the reported LIGO/Virgo 
S190517h event (GCN #24570
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 ), trigger time 2019-05-17T05:51:01.831 UTC. 
At T0, more than 99.8% of the LIGO localization region was covered by 
Insight-HXMT without occultation by the Earth.

Within T0 +/- 100 s, no significant excess events (SNR > 3 sigma) are 
found in a search of the Insight-HXMT/HE raw light curves.

Assuming the GW counterpart GRB with three typical GRB Band spectral 
models, two typical duration timescales (1 s, 10 s) from the peak 
position of the LIGO-Virgo location probability map, the 5-sigma 
upper-limits fluence (0.2 - 5 MeV, incident energy) are reported below:

Band model 1 (alpha=-1.9, beta=-3.7, Ep=70 keV):
1 s:   1.8e-07 erg cm^-2
10 s:  6.8e-07 erg cm^-2

Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV):
1 s:   2.4e-07 erg cm^-2
10 s:  1.2e-06 erg cm^-2

Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV):
1 s:   3.9e-07 erg cm^-2
10 s:  3.4e-06 erg cm^-2

All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (deposited energy).
Only gamma-rays with energy greater than about 200 keV can penetrate
the spacecraft and leave signals in the CsI detectors installed inside
of the spacecraft.

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information could be found at: http://www.hxmt.org.

M. Ageron (CPPM/CNRS), B. Baret (APC/CNRS), A. Coleiro (APC/Universite Paris Diderot), M. Colomer (APC/Universite Paris Diderot)), D. Dornic (CPPM/CNRS), A. Kouchner (APC/Universite Paris Diderot), T. Pradier (IPHC/Universite de Strasbourg) report on behalf of the ANTARES  Collaboration:

Using on-line data from the ANTARES detector, we have performed a follow-up analysis of the recently reported LIGO/Virgo S190517h event using the 90% contour of the initial bayestar probability map provided by the GW interferometers (GCN#24570
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 ). The ANTARES visibility at the time of the alert, together with the 50% and 90% contours of the probability map  are shown in http://antares.in2p3.fr/users/pradier/S190517h.png <http://antares.in2p3.fr/users/pradier/S190517h.png>. Considering the location probability provided by the LIGO/Virgo collaborations, there is a 83.3% chance that the GW emitter was in the ANTARES **upgoing** field of view at the time of the alert. 

No up-going muon neutrino candidate events were recorded in the ANTARES sky during a +/- 500s time-window centered on the time (2019-05-17 05:51:01 UT) and in the 90% contour of the S190517h event. The expected number of atmospheric background events in the region visible by ANTARES is 3e-4 in the +/- 500s time window. An extended search during +/- 1 hour gives no up-going muon neutrino coincidence. The expected number of atmospheric background events in the region visible by ANTARES is 2.13e-3 in this larger time window.

ANTARES is the largest undersea neutrino detector, installed in the Mediterranean Sea, and it is primarily sensitive to neutrinos in the TeV-PeV  energy range. At 10 TeV, the median angular resolution for muon neutrinos is about 0.5 degrees. In the range 1-100 TeV ANTARES has a competitive sensitivity to this position in the sky.

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (NASA/GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
A. A. Breeveld (MSSL-UCL), A. P. Beardmore (U. Leicester),
D. N. Burrows (PSU), S. Campana (INAF-OAB), S. B. Cenko (NASA/GSFC),
G. Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA),
P. D'Avanzo (INAF-OAB), V. D'Elia(ASDC), S. Emery (UCL-MSSL),
P. A. Evans (U. Leicester), P. Giommi (ASI), C. Gronwall (PSU),
D. Hartmann (Clemson U.), J. A. Kennea (PSU), H. A. Krimm (NSF),
N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC),
A. Melandri (INAF-OAB), J. A. Nousek (PSU),
S. R. Oates (Uni. of Warwick), P. T. O'Brien (U. Leicester),
J. P. Osborne (U. Leicester), C. Pagani (U. Leicester),
K. L. Page (U.Leicester), M. Perri (ASDC),
J. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU),
M. H. Siegel (PSU), G. Tagliaferri (INAF-OAB), A. Tohuvavohu (PSU),
E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift team:

We report the search results in the BAT data within T0 +/- 100 s of the
LVC event S190517h (LIGO/VIRGO Collaboration GCN Circ. 24570
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 ),
where T0 is the LVC trigger time (2019-05-17T05:51:01.831 UTC).

The center of the BAT FOV at T0 is
RA = 314.254 deg,
DEC = 14.191 deg,
ROLL = 63.610 deg.
The BAT Field of View (>10% partial coding) covers 5.34% of the integrated
LVC localization probability, and 3.22% of the galaxy convolved
probability (Evans et al. 2016).

Within T0 +/- 100 s, no significant detections (signal-to-noise ratio
>~ 5 sigma) are found in the BAT raw light curves with time bins of 64 ms,
1 s, and 1.6 s. Assuming an on-axis (100% coded) short GRB with a
typical spectrum in the BAT energy range (i.e., a simple power-law model
with a power-law index of -1.32, Lien & Sakamoto et al. 2016), the 5-sigma
upper limit in the 1-s binned light curve corresponds to a flux upper limit
(15-350 keV) of ~ 7.34  x 10^-8 erg/s/cm^2.

Event data is available from T0+41.214 s to T0+44.276 s. No significant
detections are found in the 15-350 keV image made using the whole event
data time interval.

BAT retains decreased, but significant, sensitivity to rate increases for
gamma-ray events outside of its FOV. About 34.17% of the integrated LVC
localization probability was outside of the BAT FOV but above the
Earth's limb from Swift's location, and the corresponding flux upper limits
for this region are within roughly an order of magnitude higher than those
within the FOV.

The results of the BAT analysis are available at
https://swift.gsfc.nasa.gov/results/BATbursts/team_web/S190517h/web/source.html

M. Axelsson (KTH and Stockholm Univ.), F. Longo (Univ. and INFN Trieste),
N. Omodei (Stanford) and D. Kocevski (NASA/MSFC) report on behalf of the
Fermi-LAT Collaboration:

We have searched data collected by the Fermi Large Area Telescope (LAT) on
May 17, 2019, for possible high-energy (E > 100 MeV) gamma-ray emission in
spatial/temporal coincidence with the LIGO/Virgo trigger S190517h (GCN
24570
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 ).

We define "instantaneous coverage" as the integral over the region of the
LIGO
probability map that is within the LAT field of view at a given a time, and
"cumulative coverage" as the integral of the instantaneous coverage over
time. Fermi-LAT had instantaneous coverage of ~35% of the LIGO probability
at the time of the trigger (T0 = 2019-05-17 05:51:01.83 UTC), and reached
100% cumulative coverage after ~7.1ks.

We performed a search for a transient counterpart within the observed
region of
the 90% contour of the LIGO map in a fixed time window from T0 to T0 + 10
ks.
No significant sources were found.

We also performed a search which adapted the time interval of the analysis
to the exposure of each region of the sky, and no additional excesses were
found.

Energy flux upper bounds for the fixed time interval between 100 MeV and 1
GeV
for this search vary between 1.7e-10 and 4.0e-09 [erg/cm^2/s].

The Fermi-LAT point of contact for this event is Magnus Axelsson (
magaxe@kth.se).

The Fermi-LAT is a pair conversion telescope designed to cover
the energy band from 20 MeV to greater than 300 GeV
It is the product of an international collaboration between
NASA and DOE in the U.S. and many scientific institutions
across France, Italy, Japan and Sweden.

Maeve Doyle, Bozzo Enrico
V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland)
J. Rodi (IAPS-Roma, Italy)
A. Coleiro (APC, France)
S. Mereghetti (INAF IASF-Milano, Italy)

on behalf of the INTEGRAL multi-messenger collaboration:
https://www.astro.unige.ch/cdci/integral-multimessenger-collaboration

At the time of the LIGO/Virgo event S190517h (2019-05-17 05:51:01 UTC, 
hereafter T0),
INTEGRAL was operating in nominal mode. The peak of the event
localization probability was at an angle of 90 deg with respect to the
spacecraft pointing axis. This orientation implies a strongly suppressed
(8.7% of optimal) response of ISGRI, strongly suppressed (19% of
optimal) response of IBIS/Veto, and somewhat suppressed (61% of
optimal) response of SPI-ACS.

The background within +/-300 seconds around the event was rather
unstable (excess variance 1.9).

We have performed a search for any impulsive events in INTEGRAL SPI-
ACS (as described in Savchenko et al. 2012, A&A 541A, 122S), IBIS, and
IBIS/Veto data.

We do not detect any significant counterparts and estimate a 3-sigma
upper limit on the 75-2000 keV fluence of 2.7e-07 erg/cm^2 for a burst
lasting less than 1 s with a characteristic short GRB spectrum (an
exponentially cut off power law with alpha=-0.5 and Ep=600 keV)
occurring at any time in the interval within 300 s around T0. For a
typical long GRB spectrum (Band function with alpha=-1, beta=-2.5, and
Ep=300 keV), the derived peak flux upper limit is ~2.3e-07 (1.1e-08)
erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range

Y. Kawakubo (LSU), A. Yoshida, T. Sakamoto, V. Pal'shin,
S. Sugita (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu,
T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), 
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The high-voltage of the CALET Gamma-ray Burst Monitor (CGBM)
detectors were turned on around the  trigger time of S190517h, 
T0 = 2019-05-17 05:51:01.831 UT (The LIGO Scientific Collaboration
and Virgo Collaboration, GCN Circ. 24570
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 ): at T0-8 sec, T0, and
T0+8 sec for HXM1, HXM2, and SGM detector respectively. 

No CGBM on-board trigger occurred around the event time.  Based 
on the LIGO-Virgo localization sky map, the high probability area 
was out of the FOV of the HXM detectors, and partially in the FOV
of the SGM detector (the summed LIGO probabilities inside FOVs
are 0% and 61% respectively), 11% credible region of the initial
localization map  was Earth-occulted.  At T0, the HXM and SGM
FOVs were centered at RA  = 117.0 deg, Dec = -25.4 deg and 
RA = 126.0 deg, Dec = -31.6 deg, respectively.

Based on the analysis of the light curve data with 0.125 sec time 
resolution from T0-8 sec to T0+60 sec, we found no significant excess 
(signal-noise-ration >= 7) around the trigger time in either the HXM 
(7-3000 keV) or the SGM (40 keV - 28 MeV) data  (for the SGM, the 
interval is from T0+8 sec to T0+60 sec).  Also, there is no sign of the
weak excess reported by INTEGRAL SPI-ACS  at ~T0+37 s 
(Doyle et al., GCN Circ. 24571
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 ) in either the HXM or the SGM data.

The CALET Calorimeter (CAL) was operating in the high energy
trigger mode at the trigger time of S190517h. Using CAL data,
we have searched for gamma-ray events in the 10-100 GeV
band from -60 sec to +60 sec from the GW trigger time and
found no candidates. There is no significant overlap with the LVC
location probability map.  The CAL FOV was centered
at RA=126.2 deg, Dec=-31.9 deg at T0.

N.Leroy (LAL), Jicheng Zhang (THU), A. de Ugarte Postigo (HETH/IAA-CSIC,
DARK/NBI), K. Noysena (Artemis, IRAP), M. Boer (Artemis),
N. Christensen (Artemis), L. Eymar (Artemis), A. Klotz (IRAP),
S. Antier (APC), S. Basa (LAM), D. Corre (LAL), M. Coughlin (Caltech),
D.Coward (OzGrav-UWA), J.G. Ducoin (LAL), B. Gendre (OzGrav-UWA),
P. Hello (LAL), C. Lachaud (APC), N. Leroy (LAL), D. Turpin (NAOC),
X. Wang (THU)

Report on behalf of the TAROT network and GRANDMA collaborations.

We performed tiled observations of LIGO/Virgo S190517h event with the
TAROT-Chili (TCH) telescope operating in the visible located at La
Silla ESO observatory (LaS/ESO).
The observation started on 05/17/19
10:04:53 UTC which corresponds approximately to 254 minutes after the
GW trigger time.

We performed the following tiled observations :

+------------+------------+---------+---------+---------+
| TStart�������� | TEnd������������ | RA���������� | DEC�������� |���� Proba |
| [UTC]���������� | [UTC]���������� | [deg]���� | [deg]���� |�������� [%] |
|------------+------------+---------+---------+---------|
| 2019-05-17 | 2019-05-17 | 227.368 | -48.182 |�������� 3.2 |
| 10:04:53���� | 10:11:24���� |���������������� |���������������� |���������������� |
| 2019-05-17 | 2019-05-17 | 230.075 | -48.182 |�������� 3.2 |
| 10:11:43���� | 10:18:13���� |���������������� |���������������� |���������������� |
| 2019-05-17 | 2019-05-18 | 227.812 | -50�������� |�������� 2.9 |
| 10:18:31���� | 03:18:40���� |���������������� |���������������� |���������������� |
+------------+------------+---------+---------+---------+

TStart and TEnd refers respectively to the time of the first and last
exposure for a given tile. Observations are not necessarily continuous
 ��in this interval.
The Probability refers to the 2D spatial
probability of the GW skymap enclosed in a given tile. Each tile is
1.9x1.9 degrees. These observations cover about 9% of the cumulative
probability of the skymap.
The typical limiting magnitude is 18.0 for a 60.0 s exposure.

The coverage map is available at: 
https://grandma-owncloud.lal.in2p3.fr/index.php/s/j8EDTsfDQUDq1D4

According to our data analysis, no serious optical transient candidates
were found

GRANDMA (Global Rapid Advanced Network Devoted to the Multi-messenger
Addicts) is a network of robotic telescopes connected all over the
world with both photometry and spectrometry capabilities for Time-
domain Astronomy (https://grandma.lal.in2p3.fr/).
Details on the TCH telescope�� are available on the GRANDMA web pages
or on�� http://tarot.obs-hp.fr/.

 ��This circular is citable.

Z. Kostrzewa-Rutkowska (SRON/RU), S. Hodgkin, A. Delgado, D.L. Harrison, M.
van Leeuwen, G. Rixon, A. Yoldas (IoA Cambridge), D. Eappachen, P.G. Jonker
(SRON/RU) on behalf of Gaia Alerts team report the discovery of a transient
candidate within the probability skymap of S190517h (the LIGO Scientific
Collaboration and the Virgo Collaboration, GCN 24570
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 ):

---------------------------------------------------------------------------

Name      TNSid Date [TCB]          RaDeg DecDeg AlertMag URL

---------------------------------------------------------------------------

Gaia19bws AT2019fud
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  2019-05-21T21:13:10 330.61045 -53.36877 18.88

      http://gsaweb.ast.cam.ac.uk/alerts/alert/Gaia19bws/

---------------------------------------------------------------------------


Acknowledgements: This work has made use of data from the European Space
Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by
the Gaia Data Processing and Analysis Consortium (DPAC,
https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC
has been provided by national institutions, in particular the institutions
participating in the Gaia Multilateral Agreement. ZKR, DE, and PGJ
acknowledge support from the European Research Council under ERC
Consolidator Grant agreement no 647208.

A. Anumarlapudi (IITB), D. Saraogi (IITB), Aarthy E. (PRL), V. Bhalerao (IITB), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S.  Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

We have carried a search for X-ray candidates in Astrosat CZTI data in a 100 sec window around the trigger time of the BBH merger event S190517h (UTC 2019-05-17 05:51:01.000, GraceDB event). CZTI is a coded aperture mask instrument that has considerable effective area for about 29% of the entire sky, but is also sensitive to brighter transients from the entire sky. At the time of merger, Astrosat's nominal pointing is (RA=305.69, DEC=-44.30), which is 69.73 deg away from the maximum probability location. In a time interval of 100 sec around the event, 83 % of sky locations with the inclusion of maximum probability location for the event are visible in the satellite's frame and the rest of 17 % are occulted by earth.

CZTI data were de-trended to remove orbit-wise background variation. We then searched data from three of the four independent, identical quadrants to look for coincident spikes in the count rates. Searches were undertaken by binning the data in 0.1s, 1s, and 10s respectively. Statistical fluctuations in count rates were estimated by using data from 10 (+-5) neighbouring orbits. We selected confidence levels such that the probability of a false trigger in a 1000 sec window is 10^-4.We do not find any evidence for any hard X-ray transient in this window, in the CZTI energy range of 20-200 keV.

We convert our count rates into flux by assuming that the source spectrum is a power law with alpha = -1.0. We use a detailed mass model of the satellite to calculate the instrument response for every htm grid point that fall in 90% LIGO localization region and calculate flux limit in that direction. We get the following upper limits for source flux in the 20-200 keV band by taking a probability weighted mean of flux limit and are reported here :

0.1 s: flux limit= 3.8 e-7 ergs/cm^2/s
1.0 s: flux limit= 1.2 e-6 ergs/cm^2/s
10.0 s: flux limit= 2.0 e-6 ergs/cm^2/s

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.