IceCube-200117A
GCN Circular 26802
Subject
IceCube-200117A: IceCube observation of a high-energy neutrino candidate event
Date
2020-01-17T14:15:28Z (5 years ago)
From
Cristina Lagunas Gualda at DESY <cristina.lagunas@desy.de>
**
*The IceCube Collaboration (http://icecube.wisc.edu/) reports:*
*
On 20/01/17 at 11:08:29.69UT IceCube detected a track-like event with a
moderate probability of being of astrophysical origin. The event was
selected by the ICECUBE_Astrotrack_Bronze alert stream.�� The average
astrophysical neutrino purity for Bronze alerts is 30%. This alert has
an estimated false alarm rate of 1.93events per year due to atmospheric
backgrounds. The IceCube detector was in a normal operating state at the
time of detection.
After the initial automated alert
(https://gcn.gsfc.nasa.gov/notices_amon_g_b/133634_1410505.amon), more
sophisticated reconstruction algorithms have been applied offline, with
the direction refined to:
Date: 20/01/17
Time: 11:08:29.69UT
RA: 116.24 (+0.71-1.24�� deg 90% PSF containment) J2000
Dec: 29.14�� (+0.90-0.78�� 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 4FGL sources inside the 90% localization region. The
closest source is 4FGL J0746.5+2730 located at RA 116.63 deg and dec
27.52 deg�� (at a distance of 1.66 degrees from the best-fit location).
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
*
GCN Circular 26804
Subject
IceCube-200117A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
Date
2020-01-17T16:57:48Z (5 years ago)
From
Carlo Ferrigno at IAAT/ISDC <carlo.Ferrigno@unige.ch>
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 IceCube-200117A: (GCN 26802).
At the time of the event (2020-01-17 11:08:29 UTC, hereafter T0),
INTEGRAL was operating in nominal mode. The peak of the event
localization probability was at an angle of 117 deg with respect to
the spacecraft pointing axis. This orientation implies strongly
suppressed (3.6% of optimal) response of ISGRI, somewhat suppressed
(41% of optimal) response of IBIS/Veto, and somewhat suppressed (51%
of optimal) response of SPI-ACS.
The background within +/-300 seconds around the event was stable(excess
variance 1.2).
We have performed a search for 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 3.3e-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 ~2.9e-07 (9.7e-08)
erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range.
We report for completeness and in order of FAP, all excesses
identified in the search region. We find: 2 likely background
excesses:
T-T0 | scale | S/N | flux ( x 1e-06 erg/cm2/s) | FAP
7.66 | 3.5 | 3 | 1.96 +/- 0.628 +/- 0.657 | 0.052
48 | 0.1 | 4.6 | 1.73 +/- 0.379 +/- 0.581 | 0.931
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
GCN Circular 26805
Subject
IceCube-200117A: Upper limits from Fermi-GBM Observations
Date
2020-01-17T17:17:17Z (5 years ago)
From
Joshua Wood at MSFC/Fermi-GBM <joshua.r.wood@nasa.gov>
J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM team:
For the IceCube high-energy neutrino candidate event 200117A (GCN 26802), at the event time Fermi-GBM was observing the reported neutrino location at:
RA: 116.24 (+0.71 -1.24 deg 90% PSF containment) J2000
Dec: 29.14 (+0.90 -0.78 deg 90% PSF containment) J2000
There was no Fermi-GBM onboard trigger around the event time of the neutrino candidate. 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 the neutrino candidate time. From this search, no significant signal was found related to IceCube-200117A.
We set upper limits on impulsive gamma-ray emission. Using the representative soft, normal, and hard GRB-like templates described in arXiv:1612.02395, we set the following 3 sigma flux upper limits over 10-1000 keV (in units of 10^-7 erg/s/cm^2):
Timescale Soft Normal Hard
-------------------------------------------
0.128 s: 4.5 7.7 15.
1.024 s: 0.9 1.7 3.4
8.192 s: 0.4 0.5 0.8
GCN Circular 26811
Subject
IceCube-200117A: No Neutrino Counterpart in ANTARES data
Date
2020-01-18T13:41:55Z (5 years ago)
From
Antoine Kouchner at ANTARES Collaboration <kouchner@apc.in2p3.fr>
Alexis Coleiro (APC/Universite de Paris) and Damien Dornic (CPPM/CNRS) on behalf of the ANTARES Collaboration. <br> <br>
Using data from the ANTARES detector, we have performed a follow-up analysis of the recently reported single track-like event IceCube-200117A (GCN 26802< https://gcn.gsfc.nasa.gov/gcn3/26802.gcn3>). The original reconstructed origin was 17.8 degrees below the horizon for ANTARES. <br><br>
No up-going muon neutrino candidate events were recorded at the location of the IceCube event coordinates (accounting for the reported uncertainties) during a +/- 1h time-window centered on the IceCube event time, and over which the potential source remained visible all time. A search over an extended time window of +/- 1 day has also yielded no detection (32% visibility). <br><br>
This leads to a preliminary 90% confidence level upper limit on the muon-neutrino fluence from a point source of 15 GeV.cm^-2 over the energy range 6.8 TeV ��� 6.3 PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and 29 GeV.cm^-2 (1 TeV - 613 TeV) for an E^-2.5 spectrum. <br><br>
ANTARES <http://antares.in2p3.fr/ <http://antares.in2p3.fr/>> is the largest undersea neutrino detector (Mediterranean Sea) and it is primarily sensitive to astrophysical 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.
GCN Circular 26812
Subject
IceCube-200117A: Upper limits from a search for additional neutrino events in IceCube
Date
2020-01-18T16:34:51Z (5 years ago)
From
Alex Pizzuto at ICECUBE/U of Wisconsin <pizzuto@wisc.edu>
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-200117A (https://gcn.gsfc.nasa.gov/gcn3/26802.gcn3) in a time
range of 2 days centered on the alert event time (2020-01-16 11:08:19.69 UTC to 2020-01-18 11:08:19.69 UTC) during which IceCube was collecting good quality data. Excluding the
event that prompted the alert, four additional track-like events are found in spatial coincidence
with the 90% containment region of IceCube-200117A. We find that these data are consistent with atmospheric background expectations, with a p-value of 0.125. We accordingly derive a time-integrated muon-neutrino flux upper limit at the alert position of E^2 dN/ dE = 5.0 x 10^-5 TeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum are approximately between 1 TeV and 500 TeV.
A subsequent search was performed to include the month of data prior to the alert event (2019-12-18 11:08:19.69 UTC to 2020-01-18 11:08:19.69 UTC). In this case, we report a p-value of 1.0, consistent with no significant excess of track-like events, and a corresponding time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2 dN/dE) of
8.0 x 10^-5 TeV cm^-2 at the 90% CL.
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>.
GCN Circular 26813
Subject
IceCube-200117A: Candidate Counterpart from the Zwicky Transient Facility
Date
2020-01-18T17:31:45Z (5 years ago)
From
Simeon Reusch at DESY <simeon.reusch@desy.de>
Simeon Reusch and Robert Stein (DESY) report,
On behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations:
We observed the localization region of he neutrino event IC200117A (GCN 26802) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g-band and r-band beginning at 2020-01-18T09:06:01.700 UTC, approximately 22.0 hours after event time. We covered 2.1 sq deg, corresponding to 77.9% of the reported localization region. This estimate accounts for chip gaps. Each exposure was 300s with a typical depth of 21.0 mag.
The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019). We are left with one high-significance transientcandidate by our pipeline, lying within the 90.0% localization of the neutrino.
+---------------------------------------------------------------------------------+
| ZTF Name | IAU Name | RA (deg) | DEC (deg) | Filter | Mag | MagErr |
+---------------------------------------------------------------------------------+
| ZTF19acxopgh | AT 2019zyu | 115.0271293 | +29.2021507 | r | 20.94 | 0.20 |
+---------------------------------------------------------------------------------+
ZTF19acxopgh (AT 2019zyu) was first detected by ZTF on 2019-12-16, and has since faded roughly 1 mag. The position of ZTF19acxopgh is consistent with the nucleus of its host galaxy. The lightcurve evolution is consistent with a supernova, which would be expected for a supernova CSM-interaction model for neutrino production. Given its nuclear position, it could also be a tidal disruption event.
We encourage spectroscopic follow-up to discern the nature of this event.
ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia.
ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341.
GROWTH acknowledges the generous support of the NSF under PIRE Grant No 1545949.
Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019).
GCN Circular 26815
Subject
IceCube-200117A : Upper limits from Insight-HXMT/HE observations
Date
2020-01-18T19:14:03Z (5 years ago)
From
YaoGuang Zheng at IHEP <zhengyg@ihep.ac.cn>
Y. G. Zheng, C. Cai, Y. F. Du, W. C. Xue,
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 trigger time
(T0=2020-01-17T11:08:29.69 UTC) of this high-energy neutrino event
(GCN #26802), 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 neutrino 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: 6.7e-08 erg cm^-2
10s: 5.3e-07 erg cm^-2
Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV):
1s: 1.0e-07 erg cm^-2
10s: 9.3e-07 erg cm^-2
Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV):
1s: 3.7e-07 erg cm^-2
10s: 3.1e-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.
GCN Circular 26816
Subject
IceCube-200117A: One Additional Candidate Counterpart from the Zwicky Transient Facility
Date
2020-01-19T15:18:05Z (5 years ago)
From
Simeon Reusch at DESY <simeon.reusch@desy.de>
Simeon Reusch and Robert Stein (DESY) report,
On behalf of the Zwicky Transient Facility (ZTF) and the Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations:
We observed the localization region of the neutrino event IC200117A (GCN 26802) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g-band and r-band beginning at 2020-01-18T09:06:01.700 UTC, approximately 22.0 hours after event time. We covered 2.7 sq deg, corresponding to 99.9% of the reported localisation region. This estimate accounts for chip gaps. Each exposure was 300s with a typical depth of 21.0 mag.
The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019). After an additional night of ZTF follow-up, we detected another high-significance transient candidate lying within the 90.0% localization of the skymap:
+---------------------------------------------------------------------------------+
| ZTF Name | IAU Name | RA (deg) | DEC (deg) | Filter | Mag | MagErr |
+---------------------------------------------------------------------------------+
| ZTF20aaglixd | AT 2020agt | 116.9488624 | +28.6654337 | g | 21.25 | 0.19 |
+---------------------------------------------------------------------------------+
ZTF20aaglixd (AT 2020agt) was first detected on 2020-01-19. The lightcurve evolution is compatible with ZTF20aaglixd being a young supernova. A high-energy neutrino from this source would be consistent with a supernova-CSM interaction model for neutrino production.
To discern the nature of this event we encourage spectroscopic follow-up of both this object and ZTF19acxopgh/AT 2019zyu, the other potential counterpart previously identified by ZTF (Reusch and Stein, GCN 26813).
ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia.
ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341.
GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.
Alert distribution service provided by DIRAC@UW (Patterson et al. 2019).
Alert database searches are done by AMPEL (Nordin et al. 2019).
GCN Circular 26821
Subject
Fermi-LAT Gamma-ray Observations of IceCube-200117A
Date
2020-01-19T23:03:29Z (5 years ago)
From
Simone Garrappa at DESY <simone.garrappa@desy.de>
S. Garrappa (DESY-Zeuthen) and S. Buson (Univ. of Wuerzburg) on behalf
of the Fermi-LAT collaboration:
We report an analysis of observations of the vicinity of the high-energy
IC200117A neutrino event (GCN 26802) 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 2020-01-17 11:08:29.69 UT
(T0) with J2000 position RA = 116.24 (+0.71, -1.24) deg, Decl. = 29.14
�(+0.90, -0.78) deg 90% PSF containment. No cataloged >100 MeV
gamma-ray sources are located within the 90% IC200117A 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 IC200117A 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 < 4e-10 ph cm^-2 s^-1 for ~11-years (2008-08-04 /
2020-01-17 UTC), < 5e-8 (< 1.4e-7) ph cm^-2 s^-1 for a 1-month (1-day)
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 S. Garrappa (simone.garrappa at desy.de
<http://desy.de/>) and S. Buson (sara.buson at uni-wuerzburg.de
<http://uni-wuerzburg.de/>). 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.
GCN Circular 26828
Subject
IceCube 200117A: No significant detection in HAWC
Date
2020-01-20T14:37:56Z (5 years ago)
From
Hugo Ayala at Pennsylvania State University <hgayala@psu.edu>
Hugo Ayala (PSU) reports on behalf of the HAWC
collaboration (http://www.hawc-observatory.org/collaboration):
On 2020/01/17 11:08:29 UTC, the IceCube collaboration reported a
track-like very-high-energy event that has a high probability of
being an astrophysical neutrino, IceCube-200109A. Location is at
RA: 116.24 (+0.71/-1.24 90% PSF containment) J2000
Dec: 29.14 (+0.9/-0.78 deg 90% PSF containment) J2000
https://gcn.gsfc.nasa.gov/gcn3/26802.gcn3
(GCN circular 26802).
We performed two types of analyses for the follow-up. The first is for
a steady source in archival data and the second is a search for a
transient source. We assume a power-law spectrum with an index of -2.3
for both analyses.
Search for a steady source in archival data:
The archival data spans from November 2014 to November 2019.
We searched inside the IceCube error region from the circular.
The highest significance, 1.97 sigma (0.23 post-trials),
is at RA 116.02 deg, Dec 29.78 deg (+-1.8 deg 68% containment) J2000.
We set a time-integrated 95% CL upper limit on gamma rays at the
maximum position of:
E^2 dN/dE = 2.32e-13 (E/TeV)^-0.3 TeV cm^-2 s^-1
Search for a transient source.
Since the IceCube event falls inside the HAWC field of view,
we report on the result for the current transit of the IceCube
position.
Data acquisition started on Data Start: 2020/01/16 09:26:45 UTC and ended
2020/01/18 09:41:14 UTC.
The most significant location, with 2.74 sigma (1.63 post-trials),
is at RA 116.85 deg, Dec 29.40 deg (+-1.78 deg 68% containment) J2000.
We set a time-integrated 95% CL upper limit at the position of
maximum significance of:
E^2 dN/dE = 8.11e-12 (E/1TeV)^-0.3 TeV cm^-2 s^-1
HAWC is a very-high-energy gamma-ray observatory operating in Central
Mexico at latitude 19 deg. north. Operating day and night with over
95% duty cycle, HAWC has an instantaneous field of view of 2 sr and
surveys 2/3 of the sky every day. It is sensitive to gamma rays from
300 GeV to 100 TeV.