IceCube-190503A

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

On 19/05/03 at 17:23:08 UT IceCube detected a track-like, 
very-high-energy event with a high probability of being of astrophysical 
origin. The ��event was identified by the Extremely High Energy (EHE) 
track event selection.�� The IceCube detector was in a normal operating 
state.�� EHE events typically have a neutrino interaction vertex that is 
outside the detector, produce a muon that traverses the detector volume, 
and have a high light level (a proxy for energy).

After the initial automated alert 
(https://gcn.gsfc.nasa.gov/notices_amon/42419327_132508.amon), more 
sophisticated reconstruction algorithms have been applied offline, with 
the direction refined to:


Date: 19/05/03
Time: 17:23:08.72 UT
RA: 120.28 (+0.57 -0.77 deg ��90% PSF containment) J2000
Dec: 6.35 (+0.76 -0.70 deg 90% PSF containment) J2000

We encourage follow-up by ground and space-based instruments to help 
identify a possible astrophysical source for the candidate neutrino.

There are no Fermi 4FGL or 3FHL catalog sources in the 90% region. The 
nearest known gamma-ray source is 4FGL J0800.9+0733 at RA: 120.2262 deg, 
Dec: 7.5509 deg (1.2 deg away from the best-fit event position).


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

James Rodi (IAPS-Roma, Italy), Sandro Mereghetti (INAF IASF-Milano, Italy)
V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland) A. Coleiro (APC, France)

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 Savchenko
et al. 2017, A&A 603, A46): SPI/ACS, IBIS/Veto, and IBIS  we have
performed a search for a prompt gamma-ray counterpart of
IceCube190503A (GCN 24378
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 ).

At the time of the event (2019-05-03 17:23:08 UTC, hereafter T0),
INTEGRAL was operating in nominal mode. The peak of the event
localization probability was at an angle of 170 deg with respect to
the spacecraft pointing axis. This orientation implies strongly
suppressed (3% of optimal) response of ISGRI, near-optimal (84% of
optimal) response of IBIS/Veto, and strongly suppressed (38% of
optimal) response of SPI-ACS.



https://analyse.reproducible.online/transients/dashboard/event?utc=2019-...
<https://analyse.reproducible.online/transients/dashboard/event?utc=2019-05-03T17:23:08.72&ra_deg=120.304&dec_deg=6.3568&notice_key=received-1556904219-hash-b82233148e2c3f8a635819b5055c4fff-random-OJANNL2D&parsed=%7B%22dec_deg%22%3A%206.3568%2C%20%22eventid%22%3A%20%22unknown%22%2C%20%22ivorn%22%3A%20%22ivo%3A//nasa.gsfc.gcn/AMON%23ICECUBE_EHE_Event2019-05-03T17%3A23%3A08.72_132508_042419327-463%22%2C%20%22location_kind%22%3A%20%22position%22%2C%20%22lvc_data%22%3A%20%7B%7D%2C%20%22observatory%22%3A%20%22AMON%20%28via%20VO-TAN%29%22%2C%20%22ra_deg%22%3A%20120.304%2C%20%22role%22%3A%20%22observation%22%2C%20%22utc_isot%22%3A%20%222019-05-03T17%3A23%3A08.72%22%7D&integral=%7B%22observations%22%3A%20%7B%22data_readiness%22%3A%20%22NO%20DATA%22%2C%20%22data_readiness_fraction%22%3A%200%2C%20%22hist_png%22%3A%20%22ohist.png%22%2C%20%22history_png%22%3A%20%22ohistory.png%22%2C%20%22in_15deg_fov_ks%22%3A%200%2C%20%22last_cons%22%3A%207045.12982358209%2C%20%22nearest_cons%22%3A%207045.12982358209%2C%20%22orientation_comment%22%3A%20%22bottom%22%2C%20%22sc_phi%22%3A%2010.770955906339958%2C%20%22sc_theta%22%3A%20170.37286701883434%2C%20%22summary_card%22%3A%20%22summary_card.html%22%2C%20%22t0_ijd%22%3A%207062.725207222222%2C%20%22t0_utc%22%3A%20%222019-05-03T17%3A23%3A08.72%22%2C%20%22telapse_cons%22%3A%200%2C%20%22telapse_nrt%22%3A%20856298.7028505537%7D%2C%20%22planning_advice%22%3A%20%7B%22advices%22%3A%20%5B%7B%22importance%22%3A%20%22high%22%2C%20%22reason%22%3A%20%22small%20region%22%7D%5D%2C%20%22distance%22%3A%20null%2C%20%22followup_grade%22%3A%20%22high%22%2C%20%22hasNS%22%3A%200%2C%20%22recommended_action%22%3A%20%7B%22comment%22%3A%20%22small%20region%20%28high%29%22%2C%20%22destination%22%3A%20%5B%22shift%22%2C%20%22core%22%5D%2C%20%22route%22%3A%20%22email%22%7D%2C%20%22visibility_data%22%3A%20%7B%7D%7D%2C%20%22revnum%22%3A%20%222086%22%2C%20%22scwid%22%3A%20%22208600510021%22%2C%20%22visibility%22%3A%20%7B%22visible%22%3A%200.9999999999999999%7D%7D&event_uid=b397a521147cd75e45c864325729d4fb44b002f8b2f658f643695bbe>

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 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 4e-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 ~4.1e-07 (9e-08)
erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range.

C. Fletcher (USRA) and C.M. Hui (NASA/MSFC) report on behalf of the

Fermi-GBM team:

We have searched the Fermi Gamma-ray Burst Monitor data for a
gamma-ray counterpart to IceCube-190503A (The IceCube
Collaboration, GCN 24378
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 ). The neutrino position
(RA, Dec) = (120.28, 6.35) was Earth-occulted for Fermi-GBM from about
T0-650 s to T0+1500 s. We therefore cannot set any limits on
impulsive emission.

S. Garrappa (DESY-Zeuthen, DE) and S. Buson (Univ. of Wuerzburg, DE; UMBC, USA) on behalf of the Fermi-LAT collaboration:


We report an analysis of observations of the vicinity of the high-energy IC190503A neutrino event (GCN 24378
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 ) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2019-05-03 17:23:39 UT (T0) with J2000 position RA =120.28 (+0.57 -0.77) deg, Decl. = 6.35 (+0.76 -0.70) deg 90% PSF containment. No cataloged gamma-ray sources are found within the 90% IC190503A localization error.


We searched for the existence of intermediate (months to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (>100 MeV) within the IC190503A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IceCube best-fit position, the >100 MeV flux upper limit (95% confidence) is < 1.3e-10 ph cm^-2 s^-1 for ~10.8-years (2008-08-04 / 2019-05-03), < 4.5e-9 ph cm^-2 s^-1 for a 1-month integration time before T0.


Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For this source the Fermi-LAT contact persons are Simone Garrappa (simone.garrappa at desy.de) and Sara Buson (sara.buson at astro.uni-wuerzburg.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.

Q. B. Yi, Q. Luo, C. Cai,S. Xiao , 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 HEN trigger time
(T0=2019-05-03 17:23:08  UTC). At T0, about 100% 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 HEN 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):
1s: 1.8e-07 erg cm^-2
10s: 6.1e-07 erg cm^-2

Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV):
1s: 2.7e-07 erg cm^-2
10s: 9.7e-07 erg cm^-2

Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV):
1s: 4.6e-07 erg cm^-2
10s: 2.2e-06 erg cm^-2
Further analysis will be reported in the following circulars.

All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (record 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 telescope.

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

WeiKang Zheng, Keto Zhang, Sergiy Vasylyev and Alexei V. Filippenko
(UC Berkeley) report on behalf of the Lick/KAIT follow-up team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to the IceCube neutrino candidate event
IceCube-190503A (GCN 24378
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 ). We observed 54 galaxies within the
IceCube error circle that were selected from the Glade catalog V1.0
(Dalya et al., 2018, MNRAS, 479, 2374; http://aquarius.elte.hu/glade/)
according to their priority score and elevation visibility, with each
clear-filter exposure time being 60 s. The first image was taken at
04:39:59, May 04 UT, about 11.3 hours after the trigger, and the last
image at 05:45:42 UT. Template images were obtained next night on
May 05 , 2019. The images were processed through the KAIT
subtraction pipeline to search for potential optical counterparts.
No viable transients were identified and the analysis is ongoing.
Our typical limiting mag is 19.0. A full list of galaxies observed
by KAIT is given below.

GladeID  UT(May 04)  RA (J2000)   Dec
-----------------------------------------------
G0964222 04:39:59 08:01:55.870 +06:12:04.90
G0563204 04:41:08 08:02:24.720 +06:05:20.30
G0867044 04:42:18 08:01:54.010 +06:12:00.10
G1094027 04:43:27 08:03:08.020 +06:21:57.40
G1234036 04:44:34 08:01:41.170 +06:27:17.50
G0072770 04:45:44 08:02:36.450 +06:10:15.20
G0510454 04:46:53 08:01:12.160 +06:21:13.40
G1276512 04:48:02 08:01:52.520 +06:08:31.10
G1245750 04:49:12 08:02:27.870 +06:09:48.70
G0850227 04:50:21 08:02:07.260 +06:19:03.40
G0981133 04:51:30 08:01:57.910 +06:06:13.00
G0820621 04:52:40 08:03:46.290 +06:11:16.50
G1641637 04:53:53 08:01:06.850 +06:38:54.10
G1075330 04:55:02 08:02:40.480 +06:34:09.80
G1070846 04:56:12 08:03:03.850 +06:08:40.20
G0346609 04:57:21 08:03:33.130 +06:21:58.90
G0849480 04:58:30 08:00:39.680 +06:04:32.90
G0834707 04:59:40 08:01:11.220 +06:27:24.60
G0954061 05:00:49 08:01:45.990 +05:54:50.70
G1240435 05:01:58 08:01:10.160 +06:09:12.90
G0974364 05:03:07 08:00:58.540 +06:15:37.80
G0419170 05:04:17 08:03:30.550 +06:36:42.80
G1401952 05:05:26 08:00:19.530 +06:17:48.20
G0733806 05:06:35 08:02:44.780 +06:05:01.60
G0310669 05:07:45 08:01:03.260 +06:08:44.80
G0131957 05:08:54 08:01:58.690 +06:38:07.20
G1475382 05:10:03 08:03:52.140 +06:02:15.50
G1244242 05:11:12 08:01:08.860 +06:07:10.80
G1468878 05:12:22 08:03:50.260 +06:21:40.50
G1414455 05:13:31 08:00:42.320 +06:18:41.10
G0979388 05:19:08 08:02:48.490 +05:49:39.70
G0876280 05:20:17 08:00:39.770 +06:03:53.00
G0876660 05:21:27 08:01:03.590 +06:36:12.30
G0060787 05:22:36 08:01:59.900 +06:14:09.30
G0727667 05:23:45 08:03:23.750 +06:49:24.40
G1457750 05:24:54 08:04:46.510 +06:05:00.00
G0873736 05:26:04 08:02:38.190 +06:21:46.70
G1432060 05:27:11 08:01:35.880 +05:33:38.60
G0547403 05:28:20 08:02:40.000 +05:45:36.10
G1041891 05:29:30 07:59:35.620 +06:17:39.70
G0984639 05:30:39 08:03:05.920 +05:47:07.30
G1476499 05:31:48 08:04:22.590 +06:04:00.80
G0466629 05:32:58 08:04:47.810 +06:25:52.30
G0403378 05:34:07 08:00:14.490 +06:10:51.70
G0432549 05:35:14 08:00:28.690 +05:54:46.90
G1258519 05:36:28 08:01:26.230 +06:58:36.20
G0941209 05:37:37 08:03:06.160 +05:39:31.70
G0880361 05:38:47 08:00:36.230 +06:05:07.40
G0041485 05:39:56 08:03:03.350 +05:48:16.40
G0078389 05:41:05 08:00:08.890 +06:02:28.50
G0076618 05:42:14 07:59:55.390 +06:11:07.30
G0319796 05:43:24 08:01:46.280 +06:55:00.10
G0538304 05:44:33 08:04:17.120 +05:59:12.80
G1473979 05:45:42 08:04:48.350 +06:07:06.20

Q. B. Yi, Q. Luo, C. Cai, S. Xiao, 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 trigger time
(T0=2019-05-03 17:23:08  UTC) of this high-energy neutrino event (GCN 24381
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 ), 
which was monitored without any 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 counterpart GRB with three typical GRB Band spectral 
models, two typical duration timescales(1 s, 10 s) coming from the position of this 
neutrion event, 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):
1s: 1.8e-07 erg cm^-2   
10s: 6.1e-07 erg cm^-2 

Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV):
1s: 2.7e-07 erg cm^-2   
10s: 9.7e-07 erg cm^-2

Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV):
1s: 4.6e-07 erg cm^-2  
10s: 2.2e-06 erg cm^-2 

Further analysis will be reported in the following circulars.

All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (record 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 telescope.

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

A. Keivani (Columbia U.), D. B. Fox (PSU), P. A. Evans (U. Leicester), J.
A. Kennea (PSU), M. Santander (U. Alabama), & F. Krauss (GRAPPA/API,
University of Amsterdam) report:


The Neil Gehrels Swift Observatory observed the field of the IceCube EHE
astrophysical neutrino candidate event IceCube-190503A (revision 1,
https://gcn.gsfc.nasa.gov/gcn3/24378.gcn3
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 ) beginning May 3, 20:14:26 UT
(2.85 hours after the neutrino arrival time).

Swift utilized its onboard 19-point tiling pattern to cover a region
centered on R.A., Dec. (J2000) = 120.28d, +6.35d, with a radius of
approximately 0.8 deg; estimated 90%-containment radii for this event are
0.57 deg  to 0.77 deg depending on position angle. Swift-XRT collected ~800
s per field of PC mode data per tile between 20:17:30 UT on 3 May and
10:51:09 UT on 4 May. Data have been reduced using the analysis approach
and software routines of Evans et al. 2014 (ApJS, 210, 8).

Several X-ray sources are detected in these observations, most of which are
previously uncataloged and relatively low in flux, consistent with
expectations for serendipitous (unrelated) sources over a region of this
extent. A few sources with a false positive rate of ~1% look like real
X-ray sources. However, none of them look promising to be IceCube-190503A
counterparts due to their low flux and lack of variability.

Excluding identified sources, the 3-sigma upper limit on the count rate of
any point-like counterpart over the rest of the tiled region is 0.01 ct
s^-1, which corresponds to a 0.3-10 keV flux of 4.0e-13 erg cm^-2 s^-1 for
a typical AGN spectrum (nH=3e20 cm^-2, Gamma=1.7).

Coordinates and count rates for the X-ray sources are provided below. 

Source, RA, Dec, Error_90 (arcsec), XRT count rate (ct s^-1)

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

#1: 120.75962d, 7.01880d, 11.2, 1.0 (+0.5, -0.4) e-2

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

#2: 120.56238d, 6.63466d, 5.2, --

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

#3: 119.80197d, 7.11136d, 6.7, 1.1 (+0.6, -0.4) e-2

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

#4: 120.49133d, 6.05997d, 6.7, 9 (+6, -4) e-3

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

#5: 119.81789d, 6.45455d, 6.3, 1.0 (+0.5, -0.4) e-2

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

#6: 120.14345d, 6.13111d, 7.8, 4.6 (+4.4, -2.7) e-3

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

IceCube has performed a search for additional track-like muon neutrino events arriving
from the direction of IceCube-190503A (https://gcn.gsfc.nasa.gov/gcn3/24378.gcn3
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 ) in a time
range of 2 days centered on the alert event time (2019-05-02 17:23:39 UTC to 2019-05-04 17:23:39 UTC) during which IceCube was collecting good quality data. Excluding the
event that prompted the alert, zero additional track-like events are found in spatial coincidence
with the 90% PSF containment of IceCube-190503A. We find that these data are well described
by atmospheric background expectations, with a p-value of 1.0. Accordingly, these data would
represent a time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2
dN/dE) at the 90% CL of 3.5 x 10^-5 TeV cm^-2 for this observation period. 90% of events
IceCube would detect from a source at this declination with an E^-2 spectrum are between
approximately 10 TeV and 3 PeV.

A subsequent search was performed to include the previous month of data (2019-04-03 17:23:39 UTC to 2019-05-04 17:23:39 UTC). In this case, we also report a p-value of 1.0,
consistent with no significant excess of track events, and a corresponding time-integrated
muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2 dN/dE) at the 90% CL of
6.7 x 10^-5 TeV cm^-2.

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<mailto:roc@icecube.wisc.edu><mailto:roc@icecube.wisc.edu>.