TITLE: GCN CIRCULAR
NUMBER: 34764
SUBJECT: Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
DATE: 23/09/25 13:26:28 GMT
FROM: Lorenzo Scotton at UAH <lscottongcn(a)outlook.com>
C. Malacaria (ISSI) report on behalf of the Fermi GBM Team:
"The Fermi Gamma-ray Burst Monitor (GBM) trigger 230925241 / 717313591
at 05:46:26.17 on 25 September 2023 , tentatively classified as a GRB, is in
fact not due to a GRB. This trigger is due to Local particles.
For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
View this GCN Circular online at https://gcn.nasa.gov/circulars/34764.
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TITLE: GCN CIRCULAR
NUMBER: 34763
SUBJECT: LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
DATE: 23/09/25 04:04:03 GMT
FROM: Antonella Palmese at Carnegie Mellon University <apalmese(a)andrew.cmu.edu>
Tomás Cabrera (CMU), Lei Hu (CMU), Igor Andreoni (UMD), Keerthi Kunnumkai (CMU), Brendan O’Connor (CMU), Antonella Palmese (CMU), on behalf of the GW-MMADS team
We observed the high probability area of the LVK gravitational wave candidate S230922g (GCN 34757) using the wide-field Dark Energy Camera (DECam) on the 4m Blanco telescope, as part of the Gravitational Wave Multi-Messenger Astronomy DECam Survey (GW-MMADS; PI: Andreoni & Palmese). Observations started at 2023-09-23 00:37 UTC on the first night and 2023-09-23 23:42 UTC on the second night. The first night’s observations were impacted by clouds and only covered a fraction of the planned observations in g band. The second night’s observations covered 70% CI of the Bilby S230922g skymap (GCN 34758) spatial probability in g and i band. The median 5sigma depths of our exposures are g~22.8 mag and i~22.9 mag.
We run the SFFT difference imaging (Hu et al. 2022) on the available images, filter out likely stars and moving objects, and visually inspect the remaining transients. We report on TNS transients within the LVK 90% CI area, and report here those that we do not currently exclude as candidate counterparts based on available redshift information:
| TNS Name | RA | dec | Internal Name | Discovery Mag | Filter | Discovery Date (UT)|
| AT 2023tou | 22:18:20.254 | -17:46:08.13 | T202309242218203m174608 | 21.61 | g | 2023-09-24 04:40:35.040 |
| AT 2023tos | 22:30:44.167 | -22:17:27.51 | T202309232230442m221728 | 21.49 | g | 2023-09-24 02:49:27.552 |
| AT 2023toq | 22:14:29.326 | -26:37:43.27 | T202309242214293m263743 | 20.24 | g | 2023-09-24 04:00:04.608 |
| AT 2023top | 22:19:56.773 | -25:01:51.54 | T202309242219568m250152 | 21.74 | g | 2023-09-24 03:08:02.112 |
| AT 2023too | 22:34:53.892 | -30:29:31.00 | T202309242234539m302931 | 21.38 | g | 2023-09-24 04:04:53.184 |
| AT 2023tom | 22:18:37.979 | -21:40:53.30 | T202309242218380m214053 | 21.91 | g | 2023-09-24 03:44:43.584 |
| AT 2023toj | 22:47:55.439 | -14:06:41.45 | T202309242247554m140641 | 20.46 | g | 2023-09-24 04:31:36.768 |
| AT 2023toi | 22:43:50.303 | -29:10:48.27 | T202309242243503m291048 | 21.17 | g | 2023-09-24 04:06:22.176 |
| AT 2023toh | 22:58:08.145 | -20:11:39.61 | T202309242258081m201140 | 20.67 | g | 2023-09-24 05:31:32.736 |
| AT 2023tog | 22:04:20.455 | -24:41:16.83 | T202309242204205m244117 | 21.35 | g | 2023-09-24 04:03:06.912 |
| AT 2023tof | 22:48:36.866| | -28:29:48.33 | T202309242248369m282948 | 20.62 | g | 2023-09-24 04:06:22.176 |
| AT 2023toe | 22:42:25.888 | -16:27:41.76 | T202309242242259m162742 | 20.83 | g | 2023-09-24 03:46:26.400 |
| AT 2023toc | 23:03:05.323 | -22:47:53.46 | T202309242303053m224753 | 21.11 | g | 2023-09-24 04:26:57.696 |
Further inspection of candidate counterparts is underway.
We thank the CTIO and NOIRLab staff for supporting these observations and the data calibration.
View this GCN Circular online at https://gcn.nasa.gov/circulars/34763.
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TITLE: GCN CIRCULAR
NUMBER: 34762
SUBJECT: GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
DATE: 23/09/24 19:28:39 GMT
FROM: Christophe Adami at LAM <christophe.adami(a)lam.fr>
P. Amram, C. Adami, S. Basa (LAM/Pythéas), T. Adami (ENS Paris-Saclay), B.
Schneider (MIT), A. Saccardi, S. D. Vergani, (GEPI, Obs. de Paris), S.
Antier, A. de Ugarte Postigo (OCA), E. Le Floc'h, D. Götz, F. Schüssler,
D. Turpin (CEA-Saclay), report, on behalf of a larger collaboration:
We observed the field of GRB 230812B (Fermi GBM Team GCN, 34386 and all
subsequent GCNs) using the MISTRAL spectro-imager of Observatoire de Haute
Provence (OHP) in imaging mode. We obtained during the 2023 09 22 night 12x600s
exposure in the r'-band with a mid-epoch of 20:30 UT.
We derive the following photometry, calibrated against the Pan-STARRS catalog,
not corrected for the underlying galaxy, and not corrected for Galactic dust reddening:
2023 09 22 20:30 UT r' = 22.37 +/- 0.14
We acknowledge the excellent support from Yoann Degot-Longhi (Observatoire de Haute
Provence) and we thank Isabelle Boisse.
View this GCN Circular online at https://gcn.nasa.gov/circulars/34762.
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TITLE: GCN CIRCULAR
NUMBER: 34761
SUBJECT: LIGO/Virgo/KAGRA S230924an: Updated Sky localization
DATE: 23/09/24 18:21:08 GMT
FROM: naresh.adhikari(a)ligo.org
The LIGO Scientific Collaboration, the Virgo Collaboration, and the
KAGRA Collaboration report:
We have conducted further analysis of the LIGO Hanford Observatory
(H1) and LIGO Livingston Observatory (L1) data around the time of the
compact binary merger (CBC) candidate S230924an (GCN Circular 34760). Parameter estimation has been
performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0,
distributed via GCN Notice, is available for retrieval from the
GraceDB event page:
https://gracedb.ligo.org/superevents/S230924an
For the Bilby.multiorder.fits,0 sky map, the 90% credible region is
835 deg2. Marginalized over the whole sky, the a posteriori luminosity
distance estimate is 2358 +/- 596 Mpc (a posteriori mean +/- standard
deviation).
For further information about analysis methodology and the contents of
this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide
https://emfollow.docs.ligo.org/userguide/.
[1] Ashton et al. ApJS 241, 27 (2019)
View this GCN Circular online at https://gcn.nasa.gov/circulars/34761.
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TITLE: GCN CIRCULAR
NUMBER: 34760
SUBJECT: LIGO/Virgo/KAGRA S230924an: Identification of a GW compact binary merger candidate
DATE: 23/09/24 13:34:06 GMT
FROM: Biswajit Banerjee at Gran Sasso Science Institute (GSSI) <biswajit.banerjee(a)gssi.it>
The LIGO Scientific Collaboration, the Virgo Collaboration, and the
KAGRA Collaboration report:
We identified the compact binary merger candidate S230924an during
real-time processing of data from LIGO Hanford Observatory (H1) and
LIGO Livingston Observatory (L1) at 2023-09-24 12:44:53.840 UTC (GPS
time: 1379594711.840). The candidate was found by the CWB [1], GstLAL
[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.
S230924an is an event of interest because its false alarm rate, as
estimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2
years. The event's properties can be found at this URL:
https://gracedb.ligo.org/superevents/S230924an
The classification of the GW signal, in order of descending
probability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH
(<1%).
Assuming the candidate is astrophysical in origin, the probability
that the lighter compact object is consistent with a neutron star mass
(HasNS) is <1%. [6] Using the masses and spins inferred from the
signal, the probability of matter outside the final compact object
(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the
support of several neutron star equations of state. The probability
that either of the binary components lies between 3 and 5 solar masses
(HasMassGap) is <1%.
Two sky maps are available at this time and can be retrieved from the
GraceDB event page:
* bayestar.multiorder.fits,0, an initial localization generated by
BAYESTAR [7], distributed via GCN notice about 26 seconds after the
candidate event time.
* bayestar.multiorder.fits,1, an initial localization generated by
BAYESTAR [7], distributed via GCN notice about 5 minutes after the
candidate event time.
The preferred sky map at this time is bayestar.multiorder.fits,1. For
the bayestar.multiorder.fits,1 sky map, the 90% credible region is
1150 deg2. Marginalized over the whole sky, the a posteriori
luminosity distance estimate is 2233 +/- 617 Mpc (a posteriori mean
+/- standard deviation).
For further information about analysis methodology and the contents of
this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide
https://emfollow.docs.ligo.org/userguide/.
[1] Klimenko et al. PRD 93, 042004 (2016)
[2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.
arXiv:2305.05625 (2023)
[3] Aubin et al. CQG 38, 095004 (2021)
[4] Dal Canton et al. ApJ 923, 254 (2021)
[5] Chu et al. PRD 105, 024023 (2022)
[6] Chatterjee et al. ApJ 896, 54 (2020)
[7] Singer & Price PRD 93, 024013 (2016)
View this GCN Circular online at https://gcn.nasa.gov/circulars/34760.
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TITLE: GCN CIRCULAR
NUMBER: 34759
SUBJECT: LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
DATE: 23/09/22 14:53:25 GMT
FROM: Paolo D'Avanzo at INAF-OAB <pda.davanzo(a)gmail.com>
P. D'Avanzo (INAF-OAB), A. Reguitti (INAF-OAB / INAF-OAPd), L. Tomasella (INAF-OAPd), E. Cappellaro (INAF-OAPd), F. Onori (INAF-OAAb),
F. De Luise (INAF-OAAb), L. Tartaglia (INAF-OAAb), R. Brivio (INAF-OAB), M. Ferro (INAF-OAB), V. D’Elia (ASI/SSDC), E. Brocato (INAF-OAAb)
report on behalf ot the GRAWITA collaboration:
We carried out follow-up observations of the LIGO/Virgo/KAGRA GW trigger S230917af with the Schmidt telescopes sited in the INAF Asiago
and Campo Imperatore observatories (Italy).
Observations from Asiago have been carried out starting on 2023-09-19 at 00:44:52 UT (~ 1.61 days after the GW trigger) with the Clear, g and r filters.
A second epoch has been carried out starting on 2023-09-19 at 21:14:12 UT (~ 2.47 days after the GW trigger) with the r filter. These observations
covered ~ 86% of the localisation region of the low significance X-ray burst detected by MAXI (Negoro et al., GCN Circ. 34723) and the position of sources
S230917af_X3, S230917af_X4 and S230917af_X6 detected by Swift/XRT (Evans et al., GCN Circ. 34736).
Preliminary analysis, which includes image subtraction between the two epochs obtained in the r band, does not show evidence for promising candidate counterparts.
The typical 3sigma limiting AB magnitudes are r ~ 21 mag and r ~ 22 mag for the first and second epoch, respectively.
Observations from Campo Imperatore have have been carried out starting on 2023-09-19 at 20:14:33 UT (~ 2.42 days after the GW trigger) with the g and r filters.
These observations covered ~ 86% of the localisation region of the low significance X-ray burst detected by MAXI and the position of sources S230917af_X3,
S230917af_X4 and S230917af_X6 detected by Swift/XRT.
Preliminary analysis, which includes image subtraction with the images obtained in the first Asiago epoch, does not show evidence for promising candidate counterparts.
The typical 3sigma limiting AB magnitudes are g ~ 21.4 mag and r ~ 20.8 mag.
View this GCN Circular online at https://gcn.nasa.gov/circulars/34759.
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TITLE: GCN CIRCULAR
NUMBER: 34758
SUBJECT: LIGO/Virgo/KAGRA S230922g: Updated Sky localization
DATE: 23/09/22 09:12:45 GMT
FROM: Patricia Schmidt at University of Birmingham <patricia.schmidt(a)ligo.org>
The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:
We have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230922g (GCN Circular 34757). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the
GraceDB event page: https://gracedb.ligo.org/superevents/S230922g
For the Bilby.multiorder.fits,0 sky map, the 90% credible region is well fit by an ellipse with an area of 332 deg2 described by the
following DS9 region (right ascension, declination, semi-major axis, semi-minor axis, position angle of the semi-minor axis):
icrs; ellipse(22h34m, -22d57m, 12.85d, 8.25d, 102.09d). Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1491 +/- 443 Mpc (a posteriori mean +/- standard deviation).
For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.
[1] Ashton et al. ApJS 241, 27 (2019)
View this GCN Circular online at https://gcn.nasa.gov/circulars/34758.
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TITLE: GCN CIRCULAR
NUMBER: 34757
SUBJECT: LIGO/Virgo/KAGRA S230922g: Identification of a GW compact binary merger candidate
DATE: 23/09/22 08:40:15 GMT
FROM: v.sordini(a)ipnl.in2p3.fr
The LIGO Scientific Collaboration, the Virgo Collaboration, and the
KAGRA Collaboration report:
We identified the compact binary merger candidate S230922g during
real-time processing of data from LIGO Hanford Observatory (H1) and
LIGO Livingston Observatory (L1) at 2023-09-22 02:03:44.886 UTC (GPS
time: 1379383442.886). The candidate was found by the CWB [1], GstLAL
[2], and MBTA [3] analysis pipelines.
S230922g is an event of interest because its false alarm rate, as
estimated by the online analysis, is 1.9e-24 Hz, or about one in 1e16
years. The event's properties can be found at this URL:
https://gracedb.ligo.org/superevents/S230922g
The classification of the GW signal, in order of descending
probability, is BBH (>99%), NSBH (<1%), BNS (<1%), or Terrestrial
(<1%).
Assuming the candidate is astrophysical in origin, the probability
that the lighter compact object is consistent with a neutron star mass
(HasNS) is <1%. [4] Using the masses and spins inferred from the
signal, the probability of matter outside the final compact object
(HasRemnant) is <1%. [4] Both HasNS and HasRemnant consider the
support of several neutron star equations of state. The probability
that either of the binary components lies between 3 and 5 solar masses
(HasMassgap) is <1%.
Two sky maps are available at this time and can be retrieved from the
GraceDB event page:
* bayestar.multiorder.fits,0, an initial localization generated by
BAYESTAR [5], distributed via GCN notice about 27 seconds after the
candidate event time.
* bayestar.multiorder.fits,1, an initial localization generated by
BAYESTAR [5], distributed via GCN notice about 5 minutes after the
candidate event time.
The preferred sky map at this time is bayestar.multiorder.fits,1. For
the bayestar.multiorder.fits,1 sky map, the 90% credible region is
well fit by an ellipse with an area of 532 deg2 described by the
following DS9 region (right ascension, declination, semi-major axis,
semi-minor axis, position angle of the semi-minor axis):
icrs; ellipse(22h22m, -23d13m, 17.48d, 9.72d, 97.36d)
Marginalized over the whole sky, the a posteriori luminosity distance
estimate is 1864 +/- 473 Mpc (a posteriori mean +/- standard
deviation).
For further information about analysis methodology and the contents of
this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide
https://emfollow.docs.ligo.org/userguide/.
[1] Klimenko et al. PRD 93, 042004 (2016)
[2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.
arXiv:2305.05625 (2023)
[3] Aubin et al. CQG 38, 095004 (2021)
[4] Chatterjee et al. ApJ 896, 54 (2020)
[5] Singer & Price PRD 93, 024013 (2016)
View this GCN Circular online at https://gcn.nasa.gov/circulars/34757.
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TITLE: GCN CIRCULAR
NUMBER: 34756
SUBJECT: LIGO/Virgo/KAGRA S230922q: Identification of a GW compact binary merger candidate
DATE: 23/09/22 04:50:09 GMT
FROM: 上野昂 at RESCEU, The University of Tokyo <lpvk5082(a)g.ecc.u-tokyo.ac.jp>
The LIGO Scientific Collaboration, the Virgo Collaboration, and the
KAGRA Collaboration report:
We identified the compact binary merger candidate S230922q during
real-time processing of data from LIGO Hanford Observatory (H1) and
LIGO Livingston Observatory (L1) at 2023-09-22 04:06:58.085 UTC (GPS
time: 1379390836.085). The candidate was found by the CWB [1], GstLAL
[2], MBTA [3], and PyCBC Live [4] analysis pipelines.
S230922q is an event of interest because its false alarm rate, as
estimated by the online analysis, is 3.6e-10 Hz, or about one in 87
years. The event's properties can be found at this URL:
https://gracedb.ligo.org/superevents/S230922q
The classification of the GW signal, in order of descending
probability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH
(<1%).
Assuming the candidate is astrophysical in origin, the probability
that the lighter compact object is consistent with a neutron star mass
(HasNS) is <1%. [5] Using the masses and spins inferred from the
signal, the probability of matter outside the final compact object
(HasRemnant) is <1%. [5] Both HasNS and HasRemnant consider the
support of several neutron star equations of state. The probability
that either of the binary components lies between 3 and 5 solar masses
(HasMassGap) is <1%.
Two sky maps are available at this time and can be retrieved from the
GraceDB event page:
* bayestar.multiorder.fits,0, an initial localization generated by
BAYESTAR [6], distributed via GCN notice about 24 seconds after the
candidate event time.
* bayestar.multiorder.fits,1, an initial localization generated by
BAYESTAR [6], distributed via GCN notice about 5 minutes after the
candidate event time.
The preferred sky map at this time is bayestar.multiorder.fits,1. For
the bayestar.multiorder.fits,1 sky map, the 90% credible region is
3975 deg2. Marginalized over the whole sky, the a posteriori
luminosity distance estimate is 1110 +/- 313 Mpc (a posteriori mean
+/- standard deviation).
For further information about analysis methodology and the contents of
this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide
https://emfollow.docs.ligo.org/userguide/.
[1] Klimenko et al. PRD 93, 042004 (2016)
[2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.
arXiv:2305.05625 (2023)
[3] Aubin et al. CQG 38, 095004 (2021)
[4] Dal Canton et al. ApJ 923, 254 (2021)
[5] Chatterjee et al. ApJ 896, 54 (2020)
[6] Singer & Price PRD 93, 024013 (2016)
View this GCN Circular online at https://gcn.nasa.gov/circulars/34756.
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TITLE: GCN CIRCULAR
NUMBER: 34755
SUBJECT: LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
DATE: 23/09/22 00:23:43 GMT
FROM: Tomas Ahumada Mena at Caltech <tahumada(a)caltech.edu>
Tomas Ahumada (CIT), Vishwajeet Swain (IITB), Shreya Anand (CIT), Robert Stein (CIT), Viraj Karambelkar (CIT), Akash Anumarlapudi (UWM), Mansi Kasliwal (CIT), Anirudh Salgundi (IITB), Gaurav Waratkar (IITB), Avery Wold (IPAC), Theophile du Laz (CIT), Simeon Reusch (DESY), Igor Andreoni (SURA), Eric Bellm (UW), Varun Bhalerao (IITB), Brad Cenko (UMD), Michael Coughlin (UMN), Brian Healy (UMN), David Kaplan (UWM), Jannis Necker (DESY), D. Perley (LJMU) report on behalf of the ZTF and GROWTH collaborations:
We observed the localization region of the LVC trigger S230917af as part of routine Zwicky Transient Facility (ZTF; Graham et al., 2019; Bellm et al., 2019) survey operations. We obtained images in the r and g bands beginning at 2023-09-17T10:05:51 UT (8 seconds after the LVC trigger time), covering ~83% of the probability enclosed in the localization region. Our observations covered ~92% of the overlapping region between the MAXI low significance burst (GCN 34723) and the GW event.
We queried the ZTF alert stream using Kowalski (Duev et al. 2019) through Fritz (Coughlin et al. 2023), AMPEL (Nordin et al. 2019), and ZTFReST (Andreoni & Coughlin et al., 2021). We required at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-match our candidates with the Minor Planet Center to flag known asteroids, reject stellar sources (Tachibana and Miller 2018), and apply machine learning algorithms (Mahabal et al. 2019). We require that no spatially coincident ZTF alerts were issued before the detection time of the LVC trigger. We also run forced photometry on ZTF images (Masci et al. 2019) and require no detections before the LVC trigger.
No candidates passed our filtering criteria. Furthermore, we run forced photometry over two years of ZTF data at the center of the Swift sources circulated in Evans et al. (GCN 34736) with a 1 arcsec radius, and we queried ZTF alerts within their 90% error region. Three of the six Swift sources have previous detections and can be associated to ZTF objects. These sources are unlikely to be associated with the GW trigger:
Swift name | ZTF name | JD discovery | magnitude at discovery
---------------------------------------------------------------
S230917af_X9 | ZTF18abvbsom | 2460152.82912 | g = 20.24
S230917af_X1 | ZTF18abvucic | 2460206.80333 | g = 18.93
S230917af_X10 | ZTF18abvzkzr | 2459817.80154 | g = 20.44
No predetections or alerts in the ZTF archive were found for the Swift sources S230917af_X3, S230917af_X4, and S230917af_X6. However, we note that (1) S230917af_X3 is 2.3 arcsec from a GALEX point-like UV source, at nuv = 20.03 mag, (2) S230917af_X4 is 2.5 arcsec from a Gaia source at g = 20.62 mag with a proper motion ~5.16 mas/year, and (3) S230917af_X6 is 9 arcsec from a WISE galaxy and its colors (W1-W2 = 0.9 mag, and W2-W3 = 2.6 mag) are indicative of a QSO/Seyfert galaxy.
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) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA.
View this GCN Circular online at https://gcn.nasa.gov/circulars/34755.
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