LIGO/Virgo S200316bj

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

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




MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the LIGO/Virgo S200316bj errorbox  115 sec after notice time and 472 sec after trigger time at 2020-03-16 22:05:48 UT, with upper limit up to  16.1 mag. The observations began at zenith distance = 65 deg. The sun  altitude  is -47.1 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=11492

We obtain a following upper limits.  

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

     517 | 2020-03-16 22:05:48 |   MASTER-Kislovodsk | (05h 53m 16.56s , +47d 21m 53.5s) |   C |    90 | 13.2 |        
     638 | 2020-03-16 22:07:38 |   MASTER-Kislovodsk | (05h 53m 22.39s , +47d 20m 52.7s) |   C |   110 | 16.1 |        
Filter C is a clear (unfiltred) band. 


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

The LIGO Scientific Collaboration and the Virgo Collaboration report:

We identified the compact binary merger candidate S200316bj during
real-time processing of data from LIGO Hanford Observatory (H1), LIGO
Livingston Observatory (L1), and Virgo Observatory (V1) at 2020-03-16
21:57:56.157 UTC (GPS time: 1268431094.157). The candidate was found
by the GstLAL [1], MBTAOnline [2], and SPIIR [3] analysis pipelines.

S200316bj is an event of interest because its false alarm rate, as
estimated by the online analysis, is 7.1e-11 Hz, or about one in 1e3
years. The event's properties can be found at this URL:
https://gracedb.ligo.org/superevents/S200316bj

The classification of the GW signal, in order of descending
probability, is MassGap (>99%), Terrestrial (<1%), BNS (<1%), BBH
(<1%), or NSBH (<1%).

Assuming the candidate is astrophysical in origin, the probability
that the lighter compact object has a mass < 3 solar masses (HasNS) is
<1%. Using the masses and spins inferred from the signal, the
probability of matter outside the final compact object (HasRemnant) is
<1%.

Two sky maps are available at this time and can be retrieved from the
GraceDB event page:
 * bayestar.fits.gz,0, an initial localization generated by BAYESTAR
[4], distributed via GCN notice about 3 minutes after the candidate
event time.
 * bayestar.fits.gz,1, an initial localization generated by BAYESTAR
[4], distributed via GCN notice about 9 minutes after the candidate
event time.

The preferred sky map at this time is bayestar.fits.gz,1. For the
bayestar.fits.gz,1 sky map, the 90% credible region is 1117 deg2.
Marginalized over the whole sky, the a posteriori luminosity distance
estimate is 1222 +/- 340 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] Adams et al. CQG 33, 175012 (2016)
 [3] Qi Chu, PhD Thesis, The University of Western Australia (2017)
 [4] Singer & Price PRD 93, 024013 (2016)

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

Searches [1,2] for track-like muon neutrino events detected by IceCube
consistent with the sky localization of gravitational-wave candidate
S200316bj
 in a time range of 1000 seconds [3] centered on the alert event time
(2020-03-16 21:49:36.157 UTC to 2020-03-16 22:06:16.157 UTC) have been
performed.

During this time period IceCube was collecting good quality data.
No significant track-like events are found in spatial coincidence of
S200316bj calculated from the map circulated in the 3-Initial notice.

IceCube's sensitivity assuming an E^-2 spectrum (E^2 dN/dE) to neutrino
point sources within the locations spanned by the 90% spatial containment
of S200316bj ranges from 0.029 to 1.067 GeV cm^-2 in a 1000 second
time window.

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


[1] Bartos et al. arXiv:1810.11467
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  (2018) and Countryman et
al.arXiv:1901.05486
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  (2019)
[2] PoS(ICRC2019)918 and Braun et al., Astroparticle Physics 29, 299 (2008)
[3] Baret et al., Astroparticle Physics 35, 1 (2011)

M. Ageron (CPPM/CNRS), B. Baret (APC/CNRS), A. Coleiro (APC/Universite de Paris), M. Colomer (APC/Universite de Paris), D. Dornic (CPPM/CNRS), A. Kouchner (APC/Universite de Paris), 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 S200316bj event using the 90% contour of the Preliminary GW_SKYMAP probability
map provided by the GW interferometers (GCN#27388
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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 at http://antares.in2p3.fr/GW/S200316bj_Preliminary.png <http://antares.in2p3.fr/GW/S200316bj_Preliminary.png>.
Considering the location probability provided by the LIGO/Virgo collaborations, there is a
26.6% 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 2020-03-16 21:57:56 and in the 90% contour of the S200316bj
event. The expected number of atmospheric background events in the region visible by ANTARES is
7.62e-05 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 5.49e-04 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.

M. Serino, S. Sugita (AGU),
N. Kawai (Tokyo Tech), H. Negoro (Nihon U.),
M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi, R. Takagi (Nihon U.),
T. Mihara, C. Guo, Y. Zhou, 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. Nakahira, Y. Sugawara, S. Ueno, H. Tomida, M. Ishikawa, 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), M. Sugizaki (NAOC)
report on behalf of the MAXI team:

We examined MAXI/GSC all-sky X-ray images (2-20 keV)
after the LVC trigger S200316bj at 2020-03-16 21:57:56.157 UTC (GCN 27388
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 ).

At the trigger time of S200316bj, the high-voltage of MAXI/GSC was off,
and it was turned on at T0+833 sec (+13.9 min).
The first one-orbit (92 min) scan observation with GSC after the event covered 99%
of the 90% credible region of the bayestar skymap from 22:11:50 to 23:24:05 UTC (T0+834 to T0+5169 sec).

No significant new source was found in the region in the one-orbit scan observation.
A typical 1-sigma averaged upper limit obtained in one scan observation
is 20 mCrab at 2-20 keV.

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

J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM Team and the GBM-LIGO/Virgo group

For S200316bj and using the initial bayestar.fits.gz,1 skymap, Fermi-GBM was observing 33.4% 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 S200316bj (GCN 27388
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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=58.3, Dec=19.5 with a radius of 67.2 degrees. We therefore set upper limits on impulsive gamma-ray emission for the LVC localization region visible to Fermi at merger time. Using the representative soft, normal, and hard GRB-like 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 GW localization probability (in units of 10^-7 erg/s/cm^2):

Timescale  Soft     Normal   Hard
------------------------------------
0.128 s:   1.7      2.5      5.3
1.024 s:   0.4      0.8      1.8
8.192 s:   0.2      0.3      0.5

Assuming the median luminosity distance of 1222 Mpc from the GW detection, we estimate the following intrinsic luminosity upper limits over the 1 keV-10 MeV energy range (in units of 10^49 erg/s):

Timescale  Soft     Normal   Hard
------------------------------------
0.128s:    4.7      6.2      22.
1.024s:    1.1      2.0      7.5
8.192s:    0.5      0.7      2.2

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

In response to the LIGO/Virgo GW event S200316bj at T0 = 2020-03-16
21:57:56.157 (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 50% of the S200316bj 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 S200316bj localization
region, from a minimum of 1.1E-06 erg cm^-2 to a maximum of 2.1E-06 erg
cm^-2 (assuming as spectral model a single power-law with photon index 1.5).

An independent procedure based on photon counting statistics provides UL
fluences in the range 0.4-1 MeV, for a 300 us integration time, from a
minimum of 1.0E-08 erg cm^-2 to a maximum of 2.1E-08 erg cm^-2.

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.

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

In response to the LIGO-Virgo GW event S200316bj at T0 = 2020-03-16
21:57:56.157 UTC a preliminary analysis of the AGILE exposure at T0 shows
that the Gamma-Ray Imaging Detector (GRID) exposure covered less than 10%
of the 90% c.l. localization region (LR) (50% of 90% c.l. LR is occulted by
Earth).

We performed an analysis of the GRID data in the energy range 50 MeV - 10
GeV over time intervals before and after T0, where good exposure of the
S200316bj 90% c.l. LR was available.

No candidate gamma-ray transient was detected.

The following preliminary GRID values of 3-sigma upper limit (UL) are
obtained:

from 1.1e-07 to 3.5e-06 erg cm^-2 s^-1, with exposure of about 50% of the
LR over the time interval ( T0 + 100s ; T0 + 200s );

These measurements were obtained with AGILE observing a large portion of
the sky in spinning mode. Additional analysis of AGILE data is in progress.

C. Ferrigno, V. Savchenko (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 combination of INTEGRAL all-sky detectors (following [1]):
SPI/ACS, IBIS/Veto, and IBIS we have performed a search for a prompt
gamma-ray counterpart of S200316bj (GCN 27388
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 ).

At the time of the event (2020-03-16 21:57:56 UTC, hereafter T0),
INTEGRAL was operating in nominal mode. The peak of the event
localization probability was at an angle of 171 deg with respect to
the spacecraft pointing axis. This orientation implies strongly
suppressed (3.9% of optimal) response of ISGRI, near-optimal (91% of
optimal) response of IBIS/Veto, and strongly suppressed (34% of
optimal) response of SPI-ACS.

The background within +/-300 seconds around the event was very 
stable(excess variance 1.2).

We have performed a search for any impulsive events in INTEGRAL SPI-
ACS (as described in [2]), 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 4.3e-07 erg/cm^2 (within the
50% probability containment region of the source localization) 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 ~4.4e-07 (7.8e-08)
erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range.

For the mean reported distance 1222.0 Mpc this corresponds to the
limit on the total isotropic equivalent energy in 1 s of 7.6e+49 erg
for the short GRB spectrum and for a long GRB spectrum isotropic
equivalent luminosity in 1 s (8 s) of 3.4e+49 erg/s (1.4e+49 erg/s)

We report for completeness and in order of FAP, all excesses
identified in the search region. We find: 4 likely background
excesses:

T-T0 | scale | S/N | luminosity ( x 1e+50 erg/s) | FAP
-26 | 0.4 | 4.3 | 14.6 +/- 4.42 +/- 9.79 | 0.152
-111 | 2.25 | 3.4 | 5.17 +/- 1.85 +/- 3.48 | 0.391
-42.2 | 0.75 | 3.2 | 7.84 +/- 3.21 +/- 5.27 | 0.857
-50.8 | 0.9 | 3.2 | 6.96 +/- 2.93 +/- 4.68 | 0.891

Note that FAP estimates (especially at timescales above 2s) may be
possibly further affected by enhanced non-stationary local background
noise. This list excludes any excesses for which FAP is close to
unity.

All results quoted are preliminary.

This circular is an official product of the INTEGRAL Multi-Messenger
team.

[1] Savchenko et al. 2017, A&A 603, A46 [2] Savchenko et al. 2012, A&A
541A, 122S

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (NASA/GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
A. P. Beardmore (U. Leicester), M. G. Bernardini (INAF-OAB),
A. A. Breeveld (MSSL-UCL), 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 (ASI-ASDC), S. Emery (UCL-MSSL),
P. A. Evans (U. Leicester), P. Giommi (ASI), C. Gronwall (PSU),
D. Hartmann (Clemson U.), J. A. Kennea (PSU),
N. Klingler (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 (U. of Birmingham), P. T. O'Brien (U. Leicester),
J. P. Osborne (U. Leicester), C. Pagani (U. Leicester),
K. L. Page (U.Leicester), M. J. Page (UCL-MSSL), M. Perri (ASDC),
J. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU),
M. H. Siegel (PSU), G. Tagliaferri (INAF-OAB), A. Tohuvavohu (U. Toronto),
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 S200316bj (LIGO/VIRGO Collaboration GCN Circ. 27388
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 ),
where T0 is the LVC trigger time (2020-03-16T21:57:56.157 UTC).

The center of the BAT field of view (FOV) at T0 is
RA = 206.093 deg,
DEC = 3.456 deg,
and the roll angle is 90.963 deg.
The BAT FOV (>10% partial coding) covers 19.77% of the integrated
LVC localization probability, and 19.64% of the galaxy convolved
probability (Evans et al. 2016). Note that the sensitivity in the BAT FOV
changes with the partial coding fraction. Please see the BAT FOV figure
in the summary page (link below) for the specific location of the LVC
region relative to the BAT FOV.

Within T0 +/- 100 s, no significant astrophysical 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.
The dip and the pulse seen at ~T+50 s is likely due
to standard calibration run during spacecraft slews.

Assuming a 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 ~ 4.46 x 10^-7 erg/s/cm^2 for the 100% coded region
(i.e., for a burst with 0 deg from BAT boresight) and ~ 9.39 x 10^-6
erg/s/cm2 for the 10% coded region (~56 deg from BAT boresight).
Assuming a luminosity of ~ 2 x 10^47 erg/s (similar to GW170817)
and an average Epeak of ~ 400 keV for short GRBs (Bhat et al. 2016),
these flux upper limits corresponds to a distance of ~ 34.03 Mpc (100%
coded)and ~ 7.41 Mpc (10% coded).

No event data are available in T0 +/- 100 s. The event data
collected via the GUANO system (Tohuvavohu et al. 2020, in prep)
were not available due to the limited availability of the TDRSS
commanding at the time.

BAT retains decreased, but significant, sensitivity to rate increases for
gamma-ray events outside of its FOV. About 61.67% 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/S200316bj/web/source_public.html

Margarita Pereyra (UNAM), Alan M. Watson (UNAM), Nat Butler (ASU), Simone
Dichiara (GSFC/UMD), Eleonora Troja (GSFC/UMD), William H. Lee (UNAM),
Alexander Kutyrev (GSFC/UMD), Rosa L. Becerra (UNAM), Diego Gonzalez
(UNAM), and Tanner Wolfram (ASU) report:

We observed LIGO/Virgo S200316bj (LIGO/Virgo Collaboration, GCN Circ.
27388
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 ) with the DDOTI/OAN wide-field imager at the Observatorio Astron��mico
Nacional on Sierra San Pedro Martir (http://ddoti.astroscu.unam.mx) on the
night of 2020-03-17 UTC.

We tiled the LVC localization with two pointings centered on 05:39:01.45
+47:47:45.23 and 05:50:02.85 +46:24:27.21 (J2000). The combined field
covers about 81 square degrees and includes about 30% of the probability in
the current BAYESTAR map.

We observed from 2020-03-17 02:44 UTC to 2020-03-17 04:27 UTC (from 4.78 to
6.5 hours after the event) obtaining exposures of 28 to 45 minutes across
the field in the w filter, with 10-sigma limiting magnitudes of w = 18.2 to
w = 18.8. We calibrate our images against the APASS catalog.

Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2 catalogs we
detect no uncatalogued sources within the observed field to our 10-sigma
limit. However, we do detect the previously-cataloged transient source AT
2019dgf
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  at w = 16.8.

We thank the staff of the Observatorio Astronomico Nacional in San Pedro
Martir.



-- 
*Dr. Margarita Pereyra *

*FFTF, Schlumberger Foundation Alumnae*
----------------------------------------------------------------------------------------------------------------

*Catedr��tico Conacyt*

*Instituto de Astronom��a de la UNAM,*

*Km. 107 Carretera Tijua**na-Ensenada, *

*Ensenada Baja California, M��xico. C.P. 22860*

Oficina: 405

Skype: margarita-pereyra

M. Crnogorcevic (Univ. of Maryland & NASA/GSFC), E. Bissaldi (Politecnico & INFN Bari), 
N. Di Lalla (Stanford University), M. Axelsson (KTH & Stockholm Univ), 
D. Kocevski (NASA/MSFC), N. Omodei (Stanford Univ.) 
and F. Longo (University and INFN, Trieste)
report on behalf of the Fermi-LAT Collaboration:

We have searched data collected by the Fermi Large Area Telescope (LAT) on 
March 16, 2020, for possible high-energy (E > 100 MeV) gamma-ray emission in 
spatial/temporal coincidence with the LIGO/Virgo trigger S200316bj (GCN 27388
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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 time, and "cumulative
coverage" as the integral of the instantaneous coverage over time. Fermi-LAT had
an instantaneous coverage of ~33% of the LIGO probability at the time of the trigger
(T0 = 2020-03-16 21:57:56.158 UTC), and reached 100% cumulative coverage after ~2.3 ks.

We performed a search for a transient counterpart within the observed region of 
the 90% contour of LIGO map in a fixed time window from T0 to T0 + 10 ks. 
No significant new sources are 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 1.9e-10 and 2.0e-9 [erg/cm^2/s].
  
The Fermi-LAT point of contact for this event is 
Milena Crnogorcevic (mcrnogor@astro.umd.edu).

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.

J. Alvarez-Muniz, F. Pedreira, E. Zas (IGFAE & University of Santiago de
Compostela, Spain),
K. H. Kampert & M. Schimp (University of Wuppertal, Germany)
on behalf of the Pierre Auger Collaboration.

In response to:
LIGO/Virgo GW trigger S200316bj
T0=2020-03-16    21:57:56 UTC

We searched for Ultra-High-Energy (UHE) neutrinos with energies
above ~ 1e17 eV in data collected with the Surface Detector (SD)
of the Pierre Auger Observatory in a [-500,500] second interval
about the LIGO-Virgo trigger S200316bj as well as in a 24 hr time
interval following the event.

NO events survived the cuts applied to reject the background due
to UHE Cosmic Rays i.e. NO neutrino candidates were detected.

The field of view (fov) where the SD of Auger is sensitive to UHE
neutrinos (corresponding to inclined directions with respect to the
vertical relative to the ground) was PARTIALLY COINCIDENT (84.7%)
at the time T0 of the merger alert, with the latest LIGO/Virgo 90%
localization region (bayestar.fits.gz), achieving 100% OVERLAP
at approximately T0+2.53 hours.

-------
The Pierre Auger Observatory is an UHE Cosmic Ray detector
located in the Mendoza Province in Argentina. It consists of
an array of Water Cherenkov detectors spread over a total surface
of 3000 km^2 arranged in a triangular grid of 1.5 km side as well
as Fluorescence telescopes and other systems
(see 10.1016/j.nima.2015.06.058 for more information).
For neutrino searches with Auger, please refer to:
https://iopscience.iop.org/article/10.1088/1475-7516/2019/10/022
https://iopscience.iop.org/article/10.1088/1475-7516/2019/11/004

Y. Shimizu  (Kanagawa U), A. Yoshida, T. Sakamoto,
V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU),
K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), 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 CALET Gamma-ray Burst Monitor (CGBM) was operating at the trigger
time of S200316bj T0 = 2020-03-16 21:57:56.157 UT (The LIGO Scientific
Collaboration and Virgo Collaboration, GCN Circ. 27388
Loading...
 
 ).

No CGBM on-board trigger occurred around the event time. Based on the
LIGO-Virgo localization sky map, the summed LIGO probabilities inside
the CGBM HXM (7 - 3000 keV) and SGM (40 keV - 28 MeV) fields of view
are 52 % and 72 %, respectively (and 82 % credible region of the
initial sky map was above the horizon).  The HXM and SGM fields of
view were centered at RA = 136.4 deg, Dec = +56.1 deg and RA = 144.6 
deg, Dec = +47.5 deg at T0, respectively.

Based on the analysis of the light curve data with 0.125 sec time 
resolution from T0-60 sec to T0+60 sec, we found no significant 
excess around the trigger time 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 S200316bj. Using the 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 in the
overwrap region with the LIGO-Virgo high probability localization
region. 

The 90% upper limit of CAL is 2.8 x 10^-6 erg/cm^2/s (10-100 GeV) 
when the summed LIGO-Virgo probability reaches 35%.
The CAL FOV was centered at RA = 144.7 deg, DEC = +47.5d deg at
T0.

J. Wang (GXU), N. Dagoneau (CEA/AIM), J. Y. Wei (NAOC), S.Schanne(CEA/AIM),
X. H. Han (NAOC)

report on behalf of the SVOM Multi Messenger Astronomy and GWAC teams
(http://www.svom.fr/en/svom-mma-and-gwac-team):

We observed 10 (~1500 square deg) sky regions to cover the skymap of the
advanced LIGO/Virgo trigger S200316bj (GCN # 27388), with SVOM/GWAC, at
Xinglong Observatory. SVOM/GWAC is equipped with two sets of wide angle
cameras:
- FFOV cameras (FOV~900 square degrees/camera, aperture = 3.5 cm),
- JFOV cameras (FOV~150 square degrees/camera, aperture = 18 cm).

SVOM/GWAC currently comprises 4 FFOV cameras and 16 JFOV cameras, working
in the unfiltered band. The observations are operated in time-series mode,
taking one exposure every 25 seconds (20s exposure + 5s readout). The
observed and processed regions enclosed an estimated 63% of the probability
of the advanced LIGO/Virgo skymap.

Images were taken between ~13.5 hours and ~17.5 hours after the GW trigger
time. The coordinates of the 10 sky regions observed and their observation
times and covered probability are listed below:

Id    Ra      Dec    start (UTC)      end (UTC)    Proba.  Cam.
1  02:34:09.77 30:19:13.80  2020-03-17 11:39:57 2020-03-17 11:54:32 0.015 JFOV 
2  03:31:10.58 30:35:14.64  2020-03-17 11:26:26 2020-03-17 11:54:32 0.108 JFOV 
3  03:29:18.05 18:22:54.48  2020-03-17 11:26:26 2020-03-17 11:54:32 0.008 JFOV 
4  02:36:20.71 18:10:29.28  2020-03-17 11:47:14 2020-03-17 11:53:43 0.032 JFOV 
5  04:06:14.40 47:32:12.84  2020-03-17 12:14:47 2020-03-17 12:20:51 0.055 JFOV 
6  04:01:13.15 35:21:24.84  2020-03-17 11:57:21 2020-03-17 12:24:30 0.075 JFOV 
7  04:37:03.24 48:22:58.44  2020-03-17 11:50:53 2020-03-17 11:53:43 0.077 JFOV 
8  05:47:55.37 47:51:16.92  2020-03-17 11:46:51 2020-03-17 11:50:53 0.353 JFOV 
9  05:38:05.45 36:07:21.72  2020-03-17 11:50:30 2020-03-17 11:53:44 0.005 JFOV 
10 06:03:29.86 48:27:41.40  2020-03-17 11:56:37 2020-03-17 11:57:01 0.342 JFOV 

The sky coverage map is available at:
http://cmm.svom.cn/gwpub/O3/S200316bj/S200316bj.png
(user:svomo3 pwd:gwo3).

Weather conditions were clear during the observations. An average 3-sigma
limiting magnitude of 16 mag in the R band was obtained in the single
frames. No credible new source was detected by our online pipeline during
follow-up observations. A more detailed image analysis including
co-addition is ongoing with our offline pipeline to search for transient.

C. Cai, W. C. Xue, Y. G. Zheng, Q. Luo, S. Xiao, Q. B. Yi, 
Y. Huang, C. K. Li, G. Li, X. B. 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 
S200316bj event (GCN #27388
Loading...
 
 ), trigger time 2020-03-16T21:57:56 UTC. 
At T0, about 74% of the LIGO localization region was covered by the 
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 center 
of the LIGO-Virgo location probability map (RA=86 deg, DEC=47 deg), 
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:   1.1e-07 erg cm^-2
10 s:  4.6e-07 erg cm^-2

Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV):
1 s:   1.9e-07 erg cm^-2
10 s:  6.7e-07 erg cm^-2

Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV):
1 s:   3.0e-07 erg cm^-2
10 s:  1.2e-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. Blazek (HETH/IAA-CSIC), B. Gendre (OzGrav-UWA), M. Masek (FZU), N.
B. Orange (OWIS), Z. Vidadi (SHAO), M. Boer (Artemis), N. Christensen
(Artemis), L. Eymar (Artemis), S. Karpov (FZU), A. Klotz (IRAP), K.
Noysena (Artemis, IRAP), M. Prouza (FZU), S. Antier (APC), A. Coleiro
(APC), D. Corre (IJCLab), M. Coughlin (UMN), D. Coward (OzGrav-UWA),
J.-G. Ducoin (IJCLab), P. Hello (IJCLab), D. A. Kann (HETH/IAA-CSIC),
N. Kochiashvili (Iliauni), C. Lachaud (APC), N. Leroy (IJCLab), C.
Thoene (HETH/IAA-CSIC), D. Turpin (AIM-CEA), A. de Ugarte Postigo
(IAA/CSIC, DARK/NBI), X. Wang (THU)

report on behalf of the FRAM, TAROT and GRANDMA collaborations.

We performed tiled observations of LIGO/Virgo S200316bj event with the
FRAM-Auger, FRAM-CTA-N and TAROT-Calern (TCA) telescopes.

FRAM-Auger is located at Pierre Auger Observatory. FRAM-CTA-N is
located at Observatorio del Roque de los Muchachos. TCA is located at
Calern site at the Cote d'Azur observatory.

The following table shows for each telescope: the delay in minutes
from the trigger, which filter is used, the field of view of the
telescope in degrees and the typical limiting magnitude (AB mag) for a
given exposure in seconds (s).

+-------------+---------+----------+-------------+------------+
| Telescope   | Delay   | Filter   | f.o.v.      | Limiting   |
|             | [min]   |          | [deg]       | Mag.       |
|-------------+---------+----------+-------------+------------|
| FRAM-Auger  | 109     | R        | 1.0 x 1.0   | 18.0 (60s) |
| FRAM-CTA-N  | 23      | R        | 0.45 x 0.45 | 17.0 (90s) |
| TCA         | 16      | Clear    | 1.9 x 1.9   | 18.0 (60s) |
+-------------+---------+----------+-------------+------------+

We performed the following joint tiled observations [1] :

+-------------+------------+------------+---------+---------+---------+
| Telescope   | TStart     | TEnd       | RA      | DEC     | Proba   |
|             | [UTC]      | [UTC]      | [deg]   | [deg]   | [%]     |
|-------------+------------+------------+---------+---------+---------|
| FRAM-Auger  | 2020-03-16 | 2020-03-16 | 278.710 | -75.405 | 0.2     |
|             | 23:46:15   | 23:50:41   |         |         |         |
| FRAM-Auger  | 2020-03-16 | 2020-03-16 | 274.839 | -75.405 | 0.2     |
|             | 23:51:17   | 23:55:44   |         |         |         |
| FRAM-Auger  | 2020-03-16 | 2020-03-17 | 277.241 | -76.378 | 0.2     |
|             | 23:56:18   | 00:00:45   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 276.364 | -74.432 | 0.2     |
|             | 00:01:19   | 00:05:46   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 270.968 | -75.405 | 0.2     |
|             | 00:06:21   | 00:10:48   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 280.000 | -74.432 | 0.2     |
|             | 00:11:25   | 00:15:52   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 273.103 | -76.378 | 0.2     |
|             | 00:16:29   | 00:20:55   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 281.379 | -76.378 | 0.2     |
|             | 00:21:32   | 00:25:59   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 272.727 | -74.432 | 0.2     |
|             | 00:26:36   | 00:31:03   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 282.581 | -75.405 | 0.1     |
|             | 00:31:40   | 00:36:07   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 269.091 | -74.432 | 0.1     |
|             | 00:36:44   | 00:41:11   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 267.097 | -75.405 | 0.1     |
|             | 00:41:45   | 00:46:12   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 268.966 | -76.378 | 0.1     |
|             | 00:46:48   | 00:51:15   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 265.455 | -74.432 | 0.1     |
|             | 00:51:50   | 00:56:17   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 261.818 | -74.432 | 0.1     |
|             | 00:56:51   | 01:01:18   |         |         |         |
| FRAM-Auger  | 2020-03-17 | 2020-03-17 | 275.556 | -77.351 | 0.1     |
|             | 01:17:06   | 01:21:33   |         |         |         |
| -----       | -----      | -----      | -----   | -----   | -----   |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.144  | 47.846  | 0.3     |
|             | 22:20:16   | 22:24:22   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.011  | 47.410  | 0.3     |
|             | 22:24:37   | 22:28:43   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.517  | 46.973  | 0.3     |
|             | 22:29:00   | 22:33:06   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.368  | 47.410  | 0.3     |
|             | 22:33:22   | 22:37:28   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.654  | 47.410  | 0.3     |
|             | 22:37:44   | 22:41:50   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.122  | 48.283  | 0.3     |
|             | 22:42:04   | 22:46:10   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.880  | 46.973  | 0.3     |
|             | 22:46:25   | 22:50:31   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.243  | 46.973  | 0.3     |
|             | 22:50:44   | 22:54:50   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.495  | 47.846  | 0.3     |
|             | 22:55:05   | 22:59:11   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.536  | 46.536  | 0.3     |
|             | 22:59:26   | 23:03:32   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 85.847  | 47.846  | 0.3     |
|             | 23:03:48   | 23:07:54   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.271  | 46.536  | 0.3     |
|             | 23:08:09   | 23:12:15   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 85.815  | 48.283  | 0.3     |
|             | 23:12:31   | 23:16:37   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 87.793  | 47.846  | 0.3     |
|             | 23:16:54   | 23:21:00   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.903  | 46.536  | 0.3     |
|             | 23:21:15   | 23:25:21   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.468  | 48.283  | 0.3     |
|             | 23:25:37   | 23:29:43   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 86.599  | 48.720  | 0.3     |
|             | 23:29:58   | 23:34:04   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 85.725  | 47.410  | 0.3     |
|             | 23:34:19   | 23:38:25   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 88.154  | 46.973  | 0.3     |
|             | 23:38:43   | 23:42:49   |         |         |         |
| FRAM-CTA-N  | 2020-03-16 | 2020-03-16 | 88.441  | 47.846  | 0.2     |
|             | 23:43:04   | 23:47:10   |         |         |         |
| -----       | -----      | -----      | -----   | -----   | -----   |
| TCA         | 2020-03-16 | 2020-03-17 | 88.223  | 48.270  | 4.1     |
|             | 22:13:21   | 20:41:36   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 88.303  | 46.414  | 3.9     |
|             | 22:20:04   | 20:48:21   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 85.656  | 46.414  | 3.9     |
|             | 22:45:09   | 20:55:06   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 87.758  | 44.558  | 2.0     |
|             | 22:57:18   | 21:07:16   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 88.824  | 50.125  | 1.7     |
|             | 23:04:05   | 21:14:19   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 90.950  | 48.270  | 1.5     |
|             | 23:10:49   | 21:21:01   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 85.205  | 44.558  | 1.3     |
|             | 23:17:33   | 01:30:54   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 82.768  | 48.270  | 1.2     |
|             | 23:29:42   | 19:09:57   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 83.009  | 46.414  | 1.1     |
|             | 23:36:30   | 19:16:41   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-17 | 83.155  | 50.125  | 1.0     |
|             | 23:43:14   | 19:23:26   |         |         |         |
| TCA         | 2020-03-16 | 2020-03-16 | 69.886  | 44.558  | 0.8     |
|             | 23:49:59   | 23:56:18   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 67.333  | 44.558  | 0.7     |
|             | 00:02:08   | 19:42:22   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 86.524  | 51.981  | 0.7     |
|             | 00:08:55   | 19:49:09   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 91.659  | 50.125  | 0.6     |
|             | 00:15:40   | 00:22:00   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 67.126  | 46.414  | 0.6     |
|             | 00:28:03   | 20:08:17   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 85.495  | 48.270  | 4.2     |
|             | 00:34:51   | 20:34:51   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 85.989  | 50.125  | 2.5     |
|             | 01:00:50   | 01:07:10   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 90.950  | 46.414  | 1.3     |
|             | 18:56:52   | 21:31:02   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 90.312  | 44.558  | 0.8     |
|             | 19:29:17   | 19:35:37   |         |         |         |
| TCA         | 2020-03-17 | 2020-03-17 | 69.773  | 46.414  | 0.6     |
|             | 19:55:11   | 20:01:31   |         |         |         |
+-------------+------------+------------+---------+---------+---------+

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.

These observations cover about 34.8% of the cumulative probability of
the BAYESTAR skymap created on 2020-03-16 21:58:46 (UTC).

The coverage map is available at:
https://grandma-owncloud.lal.in2p3.fr/index.php/s/XgtMhPRxcyL09gR/
download?path=%2F&files=GRANDMA_S200316bj_1584480817.svg

No significant transient candidates were found during our low latency
analysis [2,3].

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 [2](https://grandma.lal.in2p3.fr/).

Details on the different telescopes are available on the GRANDMA web
pages.

[1] M. W Coughlin et al., MNRAS 2019, https://doi.org/10.1093/mnras/stz2485
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[2] S. Antier et al., MNRAS 2019, https://doi.org/10.1093/mnras/stz3142
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[3] K. Noysena et al., ApJ 2019, arXiv:1910.02770
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The LIGO Scientific Collaboration and the Virgo Collaboration report:

We have conducted further analysis of the LIGO Hanford Observatory
(H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1)
data around the time of the compact binary merger (CBC) candidate
S200316bj (GCN Circular 27388
Loading...
 
 ). Parameter estimation has been
performed using LALInference [1] and a new sky map,
LALInference.fits.gz,0, distributed via GCN Notice, is available for
retrieval from the GraceDB event page:

https://gracedb.ligo.org/superevents/S200316bj

The preferred sky map at this time is LALInference.fits.gz,0. For the
LALInference.fits.gz,0 sky map, the 90% credible region is 508 deg2.
Marginalized over the whole sky, the a posteriori luminosity distance
estimate is 1178 +/- 283 Mpc (a posteriori mean +/- standard
deviation).

Based on posterior support from parameter estimation [1], under the
assumption that the candidate S200316bj is astrophysical in origin,
the probability that the lighter compact object has a mass < 3 solar
masses (HasNS) is <1%. Using the masses and spins inferred from the
signal, the probability of matter outside the final compact object
(HasRemnant) is <1%.

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] Veitch et al. PRD 91, 042003 (2015)

J. Wang (GXU),  N. Dagoneau (CEA/AIM), J. Y. Wei (NAOC), S. Schanne (CEA/AIM),
X. H. Han (NAOC), L. P. Xin (NAOC)

report on behalf of the SVOM Multi Messenger Astronomy and GWAC teams
(http://www.svom.fr/en/svom-mma-and-gwac-team):

We observed 22 sky regions to cover the initial skymap of the LIGO/Virgo
trigger S200316bj (GCN # 27388), with the SVOM/GWAC-F30 telescope operated
by Huaibei Normal University and NAOC, CAS at Xinglong Observatory, China. 

The SVOM/GWAC-F30 is equipped with Standard Johnson filters and 4Kx4K FLI
CCD (FOV~1.8x1.8 degree). The GWAC-F30 is using tiling observation
strategy. The tiles are calculated to cover the most probable regions of
the 90% localization area given in the GW probability skymap. 5 images
with a single exposure of 70s time in R band are taken for each tile. The
typical limiting magnitude of our image is 17 mag in the R band calibrated
to USNO B1.0 R2. The images of GWAC-F30 cover 31.7% of skymap.

The 22 tile coordinates and the observation periods are listed below:

Id Ra          Dec         start (UTC)         end (UTC)           Proba.
0  05:46:52.80 46:45:00.00 2020-03-17 11:25:07 2020-03-17 11:31:54 0.054
1  05:47:55.20 48:27:00.00 2020-03-17 15:28:44 2020-03-17 15:40:26 0.044
2  05:56:38.40 46:45:00.00 2020-03-17 14:01:28 2020-03-17 14:14:58 0.034
3  05:37:50.40 48:27:00.00 2020-03-17 12:51:40 2020-03-17 13:04:56 0.029
4  05:46:12.00 45:02:60.00 2020-03-17 12:08:45 2020-03-17 12:22:03 0.034
5  05:58:00.00 48:27:00.00 2020-03-17 13:19:43 2020-03-17 13:32:50 0.024
6  05:37:07.20 46:45:00.00 2020-03-17 15:40:44 2020-03-17 15:55:06 0.028
7  05:49:19.20 50:08:60.00 2020-03-17 15:00:34 2020-03-17 15:14:23 0.020
8  05:38:55.20 50:08:60.00 2020-03-17 12:23:13 2020-03-17 12:36:36 0.017
9  05:55:40.80 45:02:60.00 2020-03-17 11:25:07 2020-03-17 11:38:59 0.025
10 05:59:45.60 50:08:60.00 2020-03-17 11:39:31 2020-03-17 11:52:53 0.010
11 05:36:43.20 45:02:60.00 2020-03-17 13:06:07 2020-03-17 13:19:17 0.016
12 06:06:26.40 46:45:00.00 2020-03-17 15:55:34 2020-03-17 16:00:11 0.011
13 06:08:04.80 48:27:00.00 2020-03-17 15:15:32 2020-03-17 15:28:32 0.009
14 04:39:48.00 45:02:60.00 2020-03-17 13:33:54 2020-03-17 13:47:11 0.008
15 05:45:52.80 43:21:00.00 2020-03-17 11:53:55 2020-03-17 12:07:30 0.011
16 05:55:04.80 43:21:00.00 2020-03-17 12:36:58 2020-03-17 12:50:27 0.010
17 05:40:21.60 51:51:00.00 2020-03-17 13:47:28 2020-03-17 14:01:03 0.005
18 05:27:45.60 48:27:00.00 2020-03-17 16:00:20 2020-03-17 16:15:05 0.008
19 05:51:09.60 51:51:00.00 2020-03-17 14:16:16 2020-03-17 14:29:29 0.005
20 06:05:09.60 45:02:60.00 2020-03-17 14:30:36 2020-03-17 14:43:53 0.008
21 06:10:12.00 50:08:60.00 2020-03-17 16:15:45 2020-03-17 16:20:09 0.004

The covering map is available at:
http://cmm.svom.cn/gwpub/O3/S200316bj/S200316bj_F30.png
(user:svomo3 pwd:gwo3)

The first image was taken ~11.5 hours after the event trigger time. No
credible new source is detected by our online pipeline. A more detailed
image analysis is in progress with our offline pipeline to search for any
fainter transient candidate.

A. Ridnaia, S. Golenetskii, R.Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline,
on behalf of the Konus-Wind team, report:

Konus-Wind (KW) was observing the whole sky at the time of the
LIGO/Virgo event S200316bj (2020-03-16 21:57:56.157 UTC, hereafter T0;
LIGO/Virgo Collaboration GCN Circ. 27388
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 ).

No triggered KW GRBs happened between ~4 days before and ~3 hours
after T0. Using waiting-mode data within the interval T0 +/- 100 s,
we found no significant (> 5 sigma) excess over the background
in both KW detectors on temporal scales from 2.944 s to 100 s.

We estimate an upper limit (90% conf.) on the 20 - 1500 keV fluence
to 1.1x10^-6 erg/cm^2 for a burst lasting less than 2.944 s and having a
typical KW short GRB spectrum (an exponentially cut off power law with
alpha =-0.5 and Ep=500 keV). For a typical long GRB spectrum (the Band
function with alpha=-1, beta=-2.5, and Ep=300 keV), the corresponding
limiting peak flux is 2.7x10^-7 erg/cm^2/s (20 - 1500 keV, 2.944 s scale).

All the quoted values are preliminary.