LIGO/Virgo S200114f
GCN Circular 27073
Subject
LIGO/Virgo S200114f: Gemini Spectra of AT 2020vu, AT 2020vw, AT 2020vy, and AT 2020vz
Date
2020-02-15T02:15:40Z (6 years ago)
From
Curtis McCully at Las Cumbres Observatory <cmccully@lco.global>
Curtis McCully (LCO), Daichi Hiramatsu (LCO/UCSB), Jamison Burke
(LCO/UCSB), Jennifer Andrews (UA), Craig Peligrino (LCO/UCSB), D. Andrew
Howell (LCO/UCSB), Iair Arcavi (Tel Aviv University), Reinaldo de Carvalho:
(Unicid/Unicsul), Francisco Fo��rster (Universidad de Chile), Ryan Foley
(UCSC), David Coulter (UCSC), Charles Kilpatrick (UCSC), David Sand (UA),
Stefano Valenti (UC Davis), Marcelle Soares-Santos (Brandeis), Sandro
Rembold (UFSM), Armin Rest (STSci), Daniel Kasen (UC Berkeley), Brian
Metzger (Columbia), Anthony Piro (Carnegie Obs.), Eliot Quataert (UC
Berkeley), Enrico Ramirez-Ruiz (UCSC), J. Craig Wheeler (UT Austin), Franz
Bauer (Pontificia Universidad Catolica de Chile), Joshua Bloom (UC
Berkeley), Thomas Brink (UC Berkeley), Jeff Cooke (Swinburne University of
Technology), Alejandro Clocchiatti (Pontificia Universidad Catolica de
Chile), Alexei V. Filippenko (UC Berkeley), Wendy Freedman (University of
Chicago), Peter Garnavich (Notre Dame), Jorge Ernesto Horvath (Universidade
de Sao Paulo), Saurabh Jha (Rutgers), Robert Kirshner (Gordon and Betty
Moore Foundation), Kevin Krisciunas (Texas A&M), Huan Lin (FNAL), Barry
Madore (Carnegie Obs.), Martin Makler (Centro Brasileiro de Pesquisas
Fi��sicas), Gautham Narayan (UIUC), Xavier Prochaska (UCSC), Adam Riess
(STSci), Riccardo Sturani (UFRN), Nicholas Suntzeff (Texas A&M), Masaomi
Tanaka (Tohoku University), Douglas Tucker (FNAL), Jozsef Vinko (Konkoly
Observatory), Lifan Wang (Texas A&M), Carlos Contreras (STSci), Chris
D'Andrea (UPenn), Georgios Dimitriadis (UCSC), David Jones (UCSC), Michael
Lundquist (UA), Felipe Olivares (INCT/UDA), Antonella Palmese (FNAL),
Yen-Chen Pan: (NAOJ), Daniel Scolnic (University of Chicago), WeiKang Zheng
(UC Berkeley), Antonio Bernardo (Universidade de Sao Paulo), K. Azalee
Bostroem (UC Davis), Ariadna Murguia Berthier (UCSC), O��smar Rodri��guez
(Universidad Nacional Andres Bello), Ce��sar Rojas-Bravo (UCSC), Matthew
Siebert (UCSC), and Iruata�� Souza (Centro Brasileiro de Pesquisas)
Following the detection of S200114f (LIGO/Virgo Collaboration, GCN 26734),
the Zwicky Transient Facility reported a list of possible optical
counterparts (Andreoni et al., GCN 26741). We triggered our follow-up
program on the Gemini Telescopes (GS-2019B-Q-115; PI McCully) to classify
the candidates. We obtained optical spectra of AT 2020vu, 2020vw, 2020vy,
and 2020vz using the GMOS instrument on Gemini South. These targets were
chosen because they were visible from Chile as Gemini North was closed due
to bad weather. They were observed consecutively starting at 2020-01-16
01:55 UTC, less than 48 hours after merger detection.
These targets were triggered using the TOM Toolkit (Street et al., 2018,
arXiv 1806.09557) through Gemini's programmatic interface.
The spectra were reduced using a combination of Gemini IRAF tasks and
custom Python routines (https://github.com/cmccully/lcogtgemini). We used
both SNID (Blondin & Tonry 2007, ApJ, 666, 1024) and Superfit (Howell et
al. 2005, ApJ, 634, 1190) to classify these transients. Throughout, we
adopt a Hubble constant of H_0 = 71 km/s/Mpc and a flat cosmological model
with a dark energy density of 0.7. The classifications and spectra have
been uploaded to the Transient Name Server (TNS).
For AT 2020vz, we find a best fit using Superfit of SN 2005cl, a Type IIn
SN, at +15 days with redshift z = 0.25. This corresponds to an absolute
magnitude of -19.4, consistent with this type of supernova.
https://wis-tns.weizmann.ac.il/object/2020vz
AT 2020vy was best fit by SN 1999aa before peak brightness at z = 0.24. At
this redshift, the source has an absolute magnitude of -19.2, consistent
with a SN Ia. https://wis-tns.weizmann.ac.il/object/2020vy
AT 2020vu is consistent with a quasar. The spectrum exhibits a strong,
broad feature near 5360 A. Assuming this is Mg II, the quasar is at z =
0.91. At this redshift, there are also spectral features consistent with
the hydrogen Balmer series and [O III].
https://wis-tns.weizmann.ac.il/object/2020vu
For AT 2020vw, the best fit is with a normal SN Ia near peak brightness at
z = 0.23, consistent with the absolute magnitude estimate of -19.0 at that
distance. https://wis-tns.weizmann.ac.il/object/2020vw
Therefore, we conclude that all of these transients (AT 2020vy, 2020vz,
2020vu, and 2020vw) are not associated with the GW alert S200114f.
We thank the Gemini team for their rapid response and assistance in
obtaining these observations.
GCN Circular 26875
Subject
LIGO/Virgo S200114f : No significant candidates in TAROT - FRAM - GRANDMA observations
Date
2020-01-24T21:16:02Z (6 years ago)
From
Kanthanakorn Noysena at GRANDMA-n-TAROT <kanthanakorn.noysena@irap.omp.eu>
D. Corre (IJCLab), S. Antier (APC), M. Blazek (HETH/IAA-CSIC),
P. Hello (IJCLab), E. Howell (OzGrav-UWA), S. Karpov (FZU),
M. Masek (FZU), M. Prouza (FZU), M. Boer (Artemis),
N. Christensen (Artemis), L. Eymar (Artemis), A. Klotz (IRAP),
K. Noysena (Artemis, IRAP), A. Coleiro (APC), M. Coughlin (UMN),
D. Coward (OzGrav-UWA), J.G. Ducoin (IJCLab), B. Gendre (OzGrav-UWA),
D. A. Kann (HETH/IAA-CSIC), N. Kochiashvili (Iliauni),
C. Lachaud (APC), N. Leroy (IJCLab), C. Thoene (HETH/IAA-CSIC),
D. Turpin (AIM-CEA), X. Wang (THU)
report on behalf of the FRAM, TAROT and GRANDMA collaborations.
We performed tiled observations of LIGO/Virgo S200114f event
(#GCN26734) with the FRAM-Auger, FRAM-CTA-N, TAROT-Calern (TCA),
TAROT-Chili (TCH), TAROT-Reunion (TRE) 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. TCH is located at La Silla
ESO observatory (LaS/ESO). TRE is located at Les Makes astronomical
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 | 19 | R | 1.0 x 1.0 | 18.0 (60s) |
| FRAM-CTA-N | 20 | R | 0.45 x 0.45 | 17.0 (90s) |
| TCA | 934 | Clear | 1.9 x 1.9 | 18.0 (60s) |
| TCH | 908 | Clear | 1.9 x 1.9 | 18.0 (60s) |
| TRE | 901 | Clear | 4.2 x 4.2 | 17.0 (60s) |
+-------------+---------+----------+-------------+------------+
We performed the following joint tiled observations [1] :
+-------------+------------+------------+---------+---------+---------+
| Telescope | TStart | TEnd | RA | DEC | Proba |
| | [UTC] | [UTC] | [deg] | [deg] | [%] |
|-------------+------------+------------+---------+---------+---------|
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.225 | 16.054 | 2.0 |
| | 02:27:00 | 02:31:27 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.057 | 18.973 | 1.9 |
| | 02:32:02 | 02:36:29 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 109.029 | 18.973 | 1.8 |
| | 02:37:04 | 02:41:31 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.615 | 15.081 | 1.8 |
| | 02:42:07 | 02:46:34 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.306 | 14.108 | 1.8 |
| | 02:47:10 | 02:51:36 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.847 | 17.027 | 1.8 |
| | 02:52:12 | 02:56:39 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.455 | 18.000 | 1.8 |
| | 02:57:13 | 03:01:40 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.692 | 13.135 | 1.7 |
| | 03:02:16 | 03:06:43 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 109.609 | 15.081 | 1.6 |
| | 03:07:17 | 03:11:44 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 109.213 | 16.054 | 1.6 |
| | 03:12:19 | 03:16:46 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 108.603 | 15.081 | 1.6 |
| | 03:17:20 | 03:21:47 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 108.814 | 17.027 | 1.5 |
| | 03:22:23 | 03:26:50 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 109.432 | 18.000 | 1.5 |
| | 03:27:25 | 03:31:52 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 108.202 | 16.054 | 1.4 |
| | 03:32:26 | 03:36:53 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 108.409 | 18.000 | 1.4 |
| | 03:42:46 | 03:47:13 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 110.387 | 12.162 | 1.4 |
| | 03:48:01 | 03:52:28 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 109.304 | 14.108 | 1.4 |
| | 03:53:03 | 03:57:30 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 108.000 | 18.973 | 1.3 |
| | 03:58:19 | 04:02:46 | | | |
| FRAM-Auger | 2020-01-14 | 2020-01-14 | 109.392 | 12.162 | 1.2 |
| | 04:03:23 | 04:07:50 | | | |
| ----- | ----- | ----- | ----- | ----- | ----- |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.810 | 15.516 | 0.8 |
| | 02:27:27 | 02:31:33 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.823 | 16.827 | 0.8 |
| | 02:31:51 | 02:35:57 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.850 | 14.643 | 0.8 |
| | 02:36:20 | 02:40:26 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.136 | 16.827 | 0.8 |
| | 02:41:27 | 02:45:33 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 110.558 | 17.151 | 0.7 |
| | 02:46:35 | 02:50:41 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 110.526 | 14.643 | 0.7 |
| | 02:51:03 | 02:55:09 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.120 | 17.701 | 0.7 |
| | 02:55:38 | 02:59:44 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 110.607 | 17.701 | 0.7 |
| | 03:00:03 | 03:04:09 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 108.792 | 15.516 | 0.7 |
| | 03:04:25 | 03:08:31 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.497 | 19.011 | 0.7 |
| | 03:08:49 | 03:12:55 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 108.834 | 14.643 | 0.6 |
| | 03:13:32 | 03:17:38 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 108.456 | 16.827 | 0.6 |
| | 03:18:33 | 03:22:39 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.166 | 13.332 | 0.6 |
| | 03:23:23 | 03:27:29 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 108.782 | 19.885 | 0.5 |
| | 03:27:56 | 03:32:02 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 110.173 | 19.885 | 0.5 |
| | 03:32:24 | 03:36:29 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 111.654 | 14.643 | 0.5 |
| | 03:37:40 | 03:41:46 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 111.621 | 15.516 | 0.5 |
| | 03:42:10 | 03:46:16 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.811 | 20.534 | 0.5 |
| | 03:46:42 | 03:50:48 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 107.769 | 16.827 | 0.5 |
| | 03:51:26 | 03:55:32 | | | |
| FRAM-CTA-N | 2020-01-14 | 2020-01-14 | 109.632 | 15.841 | 0.4 |
| | 03:59:12 | 04:03:18 | | | |
| ----- | ----- | ----- | ----- | ----- | ----- |
| TCA | 2020-01-14 | 2020-01-14 | 85.803 | 8.351 | <0.1 |
| | 17:41:19 | 19:42:25 | | | |
| TCA | 2020-01-17 | 2020-01-17 | 110.208 | 16.723 | 6.9 |
| | 21:04:58 | 21:11:18 | | | |
| TCA | 2020-01-17 | 2020-01-17 | 109.521 | 14.867 | 6.7 |
| | 21:14:59 | 21:19:09 | | | |
| ----- | ----- | ----- | ----- | ----- | ----- |
| TCH | 2020-01-14 | 2020-01-16 | 109.700 | 16.405 | 6.0 |
| | 17:15:25 | 04:21:59 | | | |
| TCH | 2020-01-14 | 2020-01-16 | 104.050 | 16.405 | 0.1 |
| | 17:22:11 | 04:28:31 | | | |
| TCH | 2020-01-14 | 2020-01-15 | 75.020 | 6.839 | 0.1 |
| | 17:28:56 | 21:05:11 | | | |
| TCH | 2020-01-14 | 2020-01-16 | 111.564 | 27.314 | <0.1 |
| | 17:48:06 | 04:54:10 | | | |
| TCH | 2020-01-14 | 2020-01-14 | 76.193 | 10.950 | <0.1 |
| | 18:26:42 | 21:03:03 | | | |
| TCH | 2020-01-14 | 2020-01-14 | 78.264 | -3.202 | <0.1 |
| | 18:33:27 | 21:09:51 | | | |
| TCH | 2020-01-14 | 2020-01-15 | 76.455 | -3.202 | <0.1 |
| | 18:46:11 | 19:52:31 | | | |
| TCH | 2020-01-14 | 2020-01-15 | 75.399 | 8.657 | 0.1 |
| | 20:04:52 | 18:41:26 | | | |
| TCH | 2020-01-14 | 2020-01-15 | 74.646 | 0.041 | 0.1 |
| | 20:11:37 | 21:18:06 | | | |
| TCH | 2020-01-14 | 2020-01-14 | 74.646 | -1.777 | <0.1 |
| | 20:30:45 | 20:34:55 | | | |
| TCH | 2020-01-15 | 2020-01-16 | 109.960 | 14.586 | 6.6 |
| | 18:13:17 | 04:15:13 | | | |
| ----- | ----- | ----- | ----- | ----- | ----- |
| TRE | 2020-01-14 | 2020-01-15 | 111.429 | 16.364 | 21.1 |
| | 17:09:18 | 23:15:34 | | | |
| TRE | 2020-01-14 | 2020-01-15 | 108.837 | 12.273 | 13.1 |
| | 17:22:30 | 23:28:53 | | | |
| TRE | 2020-01-14 | 2020-01-15 | 113.023 | 12.273 | 6.2 |
| | 17:34:51 | 23:41:07 | | | |
| TRE | 2020-01-14 | 2020-01-15 | 108.000 | 24.545 | 3.6 |
| | 17:48:01 | 23:54:24 | | | |
| TRE | 2020-01-14 | 2020-01-16 | 114.146 | 20.455 | 2.0 |
| | 18:00:24 | 00:06:41 | | | |
| TRE | 2020-01-14 | 2020-01-15 | 107.586 | 8.182 | 1.3 |
| | 18:13:36 | 19:19:47 | | | |
| TRE | 2020-01-14 | 2020-01-16 | 115.714 | 16.364 | 0.8 |
| | 18:25:54 | 00:32:10 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 81.818 | 4.091 | 0.7 |
| | 18:39:08 | 18:45:23 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 82.759 | 8.182 | 0.7 |
| | 18:51:24 | 18:57:40 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 79.535 | 12.273 | 0.5 |
| | 19:04:36 | 19:10:52 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 58.378 | -32.727 | 0.5 |
| | 19:16:59 | 19:23:14 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 81.818 | 0.000 | 0.4 |
| | 19:30:13 | 19:36:29 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 103.500 | 24.545 | 0.4 |
| | 19:42:29 | 19:48:45 | | | |
| TRE | 2020-01-14 | 2020-01-14 | 109.756 | 20.455 | 16.7 |
| | 22:15:54 | 22:22:09 | | | |
| TRE | 2020-01-14 | 2020-01-15 | 104.651 | 12.273 | 0.7 |
| | 23:45:02 | 19:51:19 | | | |
| TRE | 2020-01-15 | 2020-01-15 | 107.532 | 28.636 | 0.5 |
| | 20:23:20 | 20:29:38 | | | |
| TRE | 2020-01-15 | 2020-01-15 | 83.721 | 12.273 | 0.4 |
| | 20:36:32 | 20:42:49 | | | |
| TRE | 2020-01-15 | 2020-01-15 | 73.636 | 4.091 | 0.4 |
| | 20:48:55 | 20:55:10 | | | |
+-------------+------------+------------+---------+---------+---------+
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 77.3% of the cumulative probability of
the CWB skymap created on 2020-01-14 02:11:51 (UTC).
The coverage map is available at:
https://grandma-owncloud.lal.in2p3.fr/index.php/s/XgtMhPRxcyL09gR/download?path=%2F&files=GRANDMA_S200114f_1579885403.png
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
[2] S. Antier et al., MNRAS 2019, https://doi.org/10.1093/mnras/stz3142
[3] K. Noysena et al., ApJ 2019, arXiv:1910.02770
GCN Circular 26866
Subject
LIGO/Virgo S200114f: AstroSat CZTI upper limits
Date
2020-01-24T05:06:05Z (6 years ago)
From
Varun Bhalerao at Indian Inst of Tech <varunb@iitb.ac.in>
V. Shenoy (IITB), Aarthy E. (PRL), V. Bhalerao (IITB), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
We have carried a search for X-ray candidates in Astrosat CZTI data in a 100 sec window around the trigger time of the Burst event S200114f (UTC 2020-01-14 02:08:18, GraceDB event). We use the cWB.fits.gz,3 map (LVC GCN 26734; https://gracedb.ligo.org/api/superevents/S200114f/files/cWB.fits.gz,3) for our analysis. CZTI is a coded aperture mask instrument that has considerable effective area for about 29% of the entire sky, but is also sensitive to brighter transients from the entire sky. At the time of burst, Astrosat's nominal pointing is RA,DEC = 12:36:35.7, 62:15:38.8 (189.1488,62.2608), which is ~71 deg away from the maximum probability location, which severely reduces the effective area of CZTI. At the time of burst event, the Earth-satellite-transient angle corresponding to maximum probability location is ~88 deg and hence is not occulted by Earth in satellite's frame. In a time interval of 100 sec around the event, the region of the localisation map which is not occulted by Earth in the satellite's frame has a cumulative probability of 0.86 (86%).
CZTI data were de-trended to remove orbit-wise background variation. We then searched data from the four independent, identical quadrants to look for coincident spikes in the count rates. Searches were undertaken by binning the data in 0.1s, 1s, and 10s respectively. Statistical fluctuations in background count rates were estimated by using data from 10 (+-5) neighbouring orbits. We selected confidence levels such that the probability of a false trigger in a 1000 sec window is 10^-4. We do not find any evidence for any hard X-ray transient in this window, in the CZTI energy range of 20-200 keV.
We use a detailed mass model of the satellite to calculate the direction-dependent instrument response for points in the visible sky. We then assume the source is modelled as a power law with photon index alpha = -1, and convert our count rate upper limits to direction-dependent flux limits. We obtain the following upper limits for source flux in the 20-200 keV band by taking a probability weighted mean over the visible sky:
0.1 s: flux limit= 4.93e-06 ergs/cm^2/s; fluence limit = 4.93e-07 ergs/cm^2
1.0 s: flux limit= 1.59e-06 ergs/cm^2/s; fluence limit = 1.59e-06 ergs/cm^2
10.0 s: flux limit= 1.99e-07 ergs/cm^2/s; fluence limit = 1.99e-06 ergs/cm^2
CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
GCN Circular 26848
Subject
LIGO/Virgo S200114f: Upper limits from Konus-Wind observations
Date
2020-01-22T07:26:05Z (6 years ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru>
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 S200114f (2020-01-14 02:08:18.239 UTC, hereafter T0;
LIGO/Virgo Collaboration GCN Circ. 26734).
No triggered KW GRBs happened ~1.5 days before and ~1.5 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 7.9x10^-7 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 2.2x10^-7 erg/cm^2/s (20 - 1500 keV, 2.944 s scale).
All the quoted values are preliminary.
GCN Circular 26830
Subject
LIGO/Virgo S200114f: SOAR spectroscopy of AT2020zf, AT2020ace and AT2020ach
Date
2020-01-20T23:14:54Z (6 years ago)
From
Felipe Olivares E. at Millennium Institute of Astrophysics <felipe204@gmail.com>
Regis Cartier (CTIO/OIR lab), Felipe Olivares (INCT/UDA), ��smar Rodr��guez
(UNAB), Nicol��s Meza-Retamal (ESO Chile), Jonathan Quirola (PUC), Juanita
Antilen (U de Chile), Sahar Allam (Fermilab), Melissa Butner (ETSU),
Douglas Tucker (Fermilab), Marcelle Soares-Santos (Brandeis U), Martin
Makler (CBPF), Clecio R. Bom (CBPF), Luidhy Santana-Silva (Valongo
Observatory), Clara Martinez-Vazquez (CTIO/OIR lab), Alyssa Garcia
(Brandeis U), Ken Herner (Fermilab), James Annis (Fermilab), Antonella
Palmese (Fermilab), Nora Sherman (Fermilab and Brandeis U), Robert Morgan
(U of Wisconsin-Madison), Tristan Bachmann (U Chicago), and Tamara Davis (U
Queensland), on behalf of the DESGW team*:
We report SOAR Goodman spectroscopy of AT2020zf, AT2020ace and AT2020ach,
possible counterparts to the unmodeled GW event S200114f reported by the
LVC in GCN Circular No. 26734. The candidates were found by ZTF (GCN
Circular No. 26806).
We obtained 1500, 2x1500 and 2x1500 sec exposures of AT2020zf, AT2020ace
and AT2020ach, respectively, using the Goodman HTS instrument on the 4.1m
SOAR telescope at Cerro Pach��n. The SNID classifier analysis of these
spectra allow us to conclude that:
AT2020zf (ZTF20aafmdlx) is consistent with a Type Ia SN at a redshift of
0.136 (from host galaxy emission lines) around maximum.
AT2020ace (ZTF20aafrviq) is similar to Type II (pec) SNe at a redshift of
0.096 (from host galaxy emission lines). The low signal-to-noise spectrum
shows H-beta at ~5000 km/s on top of a blue continuum, however, H alpha
appears only in emission. Further observations are encouraged.
AT2020ach (ZTF20aafeaxv) is consistent with a Type Ic-BL at a redshift of
0.155 (from the SNID analysis) a few days before peak.
The SOAR followup program is a partnership between the US (PIs: Kilpatrick
& Tucker), Chilean (PI: Olivares), and Brazilian (PI: Makler) community.
Based on observations obtained at the Southern Astrophysical Research
(SOAR) telescope, which is a joint project of the Ministerio da Ciencia,
Tecnologia, Inovacoes e Comunicacoes do Brasil (MCTIC/LNA), the U.S.
National Science Foundation's National Optical Astronomy Observatory
(NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan
State University (MSU).
*The DESGW Collaboration:
Sahar Allam (Fermilab), James Annis (Fermilab), Iair Arcavi (Tel Aviv U),
Tristan Bachmann (U Chicago), Paulo Barchi (INPE & Brandeis U), Thomas
Beatty (U of Arizona) Keith Bechtol (U of Wisconsin-Madison), Federico
Berlfein (Brandeis U), Antonio Bernardo (U of Sao Paulo), Dillon Brout (U
Penn), Robert Butler (Indiana U), Melissa Butner (ETSU), Annalisa Calamida
(STScI), Hsin-Yu Chen (Harvard U), Chris Conselice (U of Nottingham),
Carlos Contreras (STScI), Jeff Cooke (Swinburne U), Chris D���Andrea (U
Penn), Tamara Davis (U Queensland), Reinaldo de Carvalho (UNICSUL), H.
Thomas Diehl (Fermilab), Zoheyr Doctor (U Chicago), Alex Drlica-Wagner
(Fermilab), Maria Drout (U Toronto), Maya Fishbach (U Chicago), Francisco
Forster (U de Chile), Ryan Foley (UCSC), Joshua Frieman (Fermilab & U
Chicago), Chris Frohmaier (U of Portsmouth), Ori Fox (STScI), Alyssa Garcia
(Brandeis U), Juan Garcia-Bellido (U Aut��noma de Madrid), Mandeep Gill
(SLAC & Stanford U), Robert Gruendl (NCSA), Will Hartley (U College
London), Kenneth Herner (Fermilab), Daniel Holz (U Chicago), Jorge Horvath
(U of Sao Paulo), D. Andrew Howell (Las Cumbres Observatory), Richard
Kessler (U Chicago), Charles Kilpatrick (UCSC), Nikolay Kuropatkin
(Fermilab), Ofer Lahav (U College London), Huan Lin (Fermilab), Andrew
Lundgren (U of Portsmouth), Martin Makler (CBPF), Clara
Martinez-Vazquez (CTIO/OIR
lab), Curtis McCully (Las Cumbres Observatory), Mitch McNanna (U of
Wisconsin-Madison), Robert Morgan (U of Wisconsin-Madison), Gautham Narayan
(STScI), Eric Neilsen (Fermilab), Robert Nichol (U of Portsmouth),
Antonella Palmese (Fermilab), Francisco Paz-Chinchon (NCSA & UIUC), Matthew
Penny (OSU), Maria Pereira (Brandeis U), Sandro Rembold (UFSM), Armin Rest
(STScI & JHU), Livia Rocha (U Sao Paulo), Russell Ryan (STScI), Masao Sako
(U Penn), Samir Salim (Indiana U), David Sand (U of Arizona), Luidhy
Santana-Silva (Valongo Observatory), Daniel Scolnic (Duke U), Nora Sherman
(Fermilab), J. Allyn Smith (Austin Peay State U), Mathew Smith (U of
Southampton), Marcelle Soares-Santos (Brandeis U), Lou Strolger (STScI),
Riccardo Sturani (UFRN), Mark Sullivan (U of Southampton), Masaomi Tanaka
(NAOJ), Nozomu Tominaga (Konan U), Douglas Tucker (Fermilab), Yousuke
Utsumi (Stanford U), Stefano Valenti (UC Davis), Kathy Vivas (CTIO/OIR lab),
Alistair Walker (CTIO/OIR lab), Sara Webb (Swinburne U), Matt Wiesner
(Benedictine U), Brian Yanny (Fermilab), Michitoshi Yoshida (NAOJ), Alfredo
Zenteno (CTIO/OIR lab).
GCN Circular 26806
Subject
LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
Date
2020-01-17T18:25:53Z (6 years ago)
From
Igor Andreoni at Caltech <igor.andreoni@gmail.com>
Igor Andreoni (Caltech), Tomas Ahumada (UMD), Simeon Reusch (DESY), Harsh Kumar (IITB), Michael W. Coughlin (Caltech), Leo Singer (NASA GSFC), Mansi M. Kasliwal (Caltech), Viraj Karambelkar (Caltech), Gaurav Waratkar (IITB), Shreya Anand (Caltech), Matthew Graham (Caltech), Jesper Sollerman (OKC)
on behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations
We continued observing the localization region of the unmodeled gravitational wave trigger S200114f (LVC, GCN #26734) on 2020-01-15 starting at 08:04:13 UTC with the Palomar 48-inch telescope equipped with the 47 square degree Zwicky Transient Facility camera (ZTF, Bellm et al. 2019, Graham et al. 2019). The tiling was optimally determined and triggered using the GROWTH Target of Opportunity marshal (Coughlin et al. 2019a, Kasliwal et al. 2019b). The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC (Masci et al. 2019).
We queried the ZTF alert stream using Kowalski (Duev et al., 2019) and AMPEL (Nordin et al., 2019), requiring at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-matched our candidates with the Minor Planet Center to flag known asteroids. We require no spatially coincident ZTF alert to be issued before the detection time of S200114f. New candidates were found within the 96% probability contour of S200114f, in addition to those reported in GCN #26741. The new transient candidates are presented in the table below.
+--------------+-----------+-------------+--------------+--------+------+----------+-------+--------+
| Name | IAU Name | RA | Dec | filter | mag | MJD | b_Gal | Notes |
+--------------+-----------+-------------+--------------+--------+------+----------+-------+--------+
| ZTF20aafefpy | AT2020acf | 07:33:43.01 | +09:31:14.29 | g | 21.2 | 58863.38 | 13.7 | (a)(c) |
| ZTF20aafrviq | AT2020ace | 07:05:04.36 | +25:07:09.97 | g | 20.5 | 58863.38 | 14.0 | (a) |
| ZTF20aafeglp | AT2020acn | 07:01:37.68 | +21:02:59.38 | g | 19.9 | 58863.38 | 11.6 | (b) |
| ZTF20aafedfu | AT2020ack | 07:08:37.86 | +23:30:00.66 | g | 21.4 | 58863.37 | 14.1 | (c) |
| ZTF20aafeaxv | AT2020ach | 07:12:02.81 | +15:11:55.51 | r | 20.3 | 58862.18 | 11.3 | (d) |
| ZTF20aafemdh | AT2020acg | 07:17:40.10 | +17:55:10.62 | g | 21.5 | 58863.37 | 13.7 | (e) |
| ZTF20aafemxx | AT2020acj | 07:18:56.78 | +16:54:18.65 | r | 21.6 | 58862.17 | 13.6 | (e) |
| ZTF20aafeszi | AT2020acm | 07:21:12.76 | +27:10:34.94 | r | 20.4 | 58862.18 | 18.1 | (e)(c) |
| ZTF20aafmdlx | AT2020zf | 03:46:00.66 | -26:50:41.00 | g | 19.5 | 58863.12 | -51.3 | (e)(f) |
| ZTF20aafshty | AT2020ada | 07:07:39.73 | +19:10:51.54 | g | 21.9 | 58862.15 | 12.1 | (c) |
| ZTF20aafeiec | AT2020acp | 07:02:31.43 | +16:10:53.08 | g | 21.1 | 58862.16 | 9.7 | (g) |
| ZTF20aafeogg | AT2020aci | 07:15:47.17 | +14:16:17.56 | r | 21.2 | 58862.18 | 11.8 | (g) |
| ZTF20aafsfki | AT2020aco | 07:09:11.26 | +09:21:16.02 | g | 21.3 | 58863.38 | 8.2 | (g)(c) |
| ZTF20aafsero | AT2020acl | 07:15:09.53 | +13:26:43.86 | r | 21.4 | 58862.18 | 11.3 | (g) |
| ZTF20aafecav | AT2020acx | 07:06:03.61 | +23:09:39.54 | g | 21.3 | 58863.37 | 13.3 | (e)(h) |
| ZTF20aafeolw | AT2020acy | 07:13:24.59 | +11:23:30.79 | r | 21.4 | 58862.18 | 9.9 | (g) |
| ZTF20aafryfe | AT2020acz | 07:38:29.43 | +12:55:02.75 | g | 21.3 | 58863.38 | 16.1 | (c) |
| ZTF20aafesaq | AT2020xb | 06:55:56.55 | +26:34:29.20 | r | 21.3 | 58863.39 | 12.6 | (e)(h) |
+--------------+-----------+-------------+--------------+--------+------+----------+-------+--------+
(a) offset from possible host
(b) close to a bright star, but not coincident
(c) AGN?
(d) Possible flaring activity
(e) on top of an apparently small galaxy
(f) first reported by ALeRCE
(g) coincident with a faint point source
(h) stellar?
We note that ZTF detections from 2018 and 2019 are present at the location of the SAGUAROc candidate (Lundquist et al., GCN #26753), which further suggests that it could be a stellar variable source.
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 filtering and follow-up coordination is being undertaken by the GROWTH marshal system (Kasliwal et al. 2019). Alert database searches are done with using the Kowalski infrastructure (Duev et al., 2019) and with AMPEL (Nordin et al. 2019).
GCN Circular 26803
Subject
LIGO/Virgo S200114f: No transients found in J-GEM observations of nearby galaxies
Date
2020-01-17T15:59:45Z (6 years ago)
From
Hiroki Onozato at University of Hyogo <onozato@nhao.jp>
R. Tanaka; K. Daikuhara; Y. Sekiguchi (Toho U.); K. Yanagisawa (NAOJ); T. Nakaoka; K. Takagi; M. Sasada; K. S. Kawabata (Hiroshima U.); H. Onozato, J. Takahashi (Hyogo U.); K. Ohta (Kyoto U.); F. Abe (Nagoya U.); M. Tanaka (Tohoku U.) on behalf of J-GEM collaboration
We report imaging observations for the gravitational wave event S200114f (LVC, GCN Circ. 26734). We started our observations from 2020-01-14 17:55 UT (MJD=58862.75) about 16 hour after the event and ended at 2020-01-16 11:56 UT (MJD=58864.50).
We performed galaxy-targeted observations for 56 galaxies (see the table below) selected from the Catalog and Atlas of the LV galaxies (LVG) (Karachentsev et al., 2004) and the GLADE catalog (Dalya et al. 2018) in the probability skymap of S200114f using the following telescopes and instruments.
We found no apparent transient objects in these galaxies to 5 sigma limiting magnitudes in the AB system listed below.
galid ra dec dist J H Ks R obsid
-------------- -------- -------- ---- ---- ---- ---- ---- -------------------
UGCA193 150.6508 -6.0119 9.7 -- 18.2 -- 19.3 Kanata-HONIR
SexA 152.7533 -4.6928 1.45 -- 18.7 -- 19.2 Kanata-HONIR
MCG_-01-26-009 150.39 -6.525 9.7 -- 18.3 -- 18.8 Kanata-HONIR
GALFA-Dw4 86.4367 10.7711 7.22 18.5 18.0 17.5 -- Nayuta-NIC,OAOWFC
KKSG15 148.7937 -6.27 9.7 -- 17.4 -- 18.2 Kanata-HONIR
NGC3115 151.3083 -7.7186 9.68 -- 16.7 -- 17.5 Kanata-HONIR
KKSG18 151.4233 -7.9814 9.7 -- -- -- 18.7 Kanata-HONIR
UGC03303 81.2479 4.505 7.14 -- 15.2 -- -- Kanata-HONIR
KKSG17 150.41 -8.2489 9.7 -- 18.2 -- 18.7 Kanata-HONIR
KK49 85.4229 6.6817 5.15 18.2 18.1 17.8 -- OAOWFC,Nayuta-NIC
ESO483-013 63.1712 -23.1589 7.4 18.5 -- -- -- OAOWFC
Orion 86.2583 5.0683 6.46 17.4 17.8 17.2 -- OAOWFC,Nayuta-NIC
A0554+07 89.4029 7.4919 5.5 18.1 18.4 18.0 -- Nayuta-NIC
IC0559 146.1829 9.6153 9.4 18.0 18.5 -- -- OAOWFC,Kanata-HONIR
DDO047 115.4792 16.8006 8.17 -- 18.4 -- 19.4 Kanata-HONIR
KK65 115.63 16.5611 7.98 -- 18.1 -- 19.7 Kanata-HONIR
SexDSph 153.2625 -1.6144 0.09 -- 18.6 -- 19.5 Kanata-HONIR
AGC174585 114.0429 9.9864 7.73 -- 18.3 -- 19.5 Kanata-HONIR
UGC03755 108.4658 10.5219 7.69 17.8 18.5 -- 19.6 OAOWFC,Kanata-HONIR
galid ra dec dist R J H obsid
--------------- -------- ------- -------- ---- ---- ---- ------------
GL071852+154033 109.7152 15.676 149.7351 19.4 -- 18.1 Kanata-HONIR
GL071845+145748 109.6861 14.9632 130.0695 19.6 -- 18.3 Kanata-HONIR
GL072133+151443 110.3871 15.2453 121.4037 19.8 -- 18.3 Kanata-HONIR
GL071720+170810 109.3354 17.136 117.0489 20.6 -- 19.1 Kanata-HONIR
GL071709+170909 109.2889 17.1524 103.1961 20.6 -- 19.1 Kanata-HONIR
GL071904+173407 109.7671 17.5685 195.1108 20.7 -- 19.3 Kanata-HONIR
GL071623+163821 109.0957 16.639 59.5044 19.9 -- 18.7 Kanata-HONIR
GL071847+174335 109.6968 17.7263 176.0128 20.1 -- 18.8 Kanata-HONIR
GL072201+145837 110.5043 14.9769 187.75 20.2 -- 19.0 Kanata-HONIR
GL071622+170440 109.0936 17.0776 184.4045 17.9 -- 17.4 Kanata-HONIR
GL072235+152917 110.6464 15.488 159.6764 19.8 -- 18.6 Kanata-HONIR
GL072235+161218 110.6446 16.2049 116.4286 20.1 -- 19.3 Kanata-HONIR
GL072220+171713 110.5836 17.2869 36.6017 19.2 -- 17.8 Kanata-HONIR
GL071536+150837 108.898 15.1436 66.3962 -- 18.0 -- OAOWFC
GL071535+150837 108.8977 15.1436 69.2797 -- 18.0 -- OAOWFC
GL071543+145815 108.9296 14.9708 131.15 -- 18.0 -- OAOWFC
GL071851+133129 109.712 13.5247 65.5892 18.7 -- 17.5 Kanata-HONIR
GL071452+142253 108.7168 14.3813 124.0912 19.7 -- 18.5 Kanata-HONIR
GL071240+180941 108.1675 18.1615 186.3849 -- 18.2 -- OAOWFC
GL071936+124014 109.9003 12.6707 119.1697 21.1 -- 19.7 Kanata-HONIR
GL071311+185631 108.2938 18.9419 145.9523 -- 17.8 -- OAOWFC
GL071204+180027 108.0146 18.0076 131.0155 -- 18.2 -- OAOWFC
GL071310+185946 108.2929 18.9961 72.2583 -- 17.8 -- OAOWFC
GL071248+184749 108.1999 18.7969 192.7041 -- 17.8 -- OAOWFC
GL071145+180852 107.9363 18.1479 155.8316 -- 18.2 -- OAOWFC
GL071150+181518 107.9597 18.2551 73.6389 -- 18.2 -- OAOWFC
GL071141+180841 107.9205 18.1448 185.7368 -- 18.2 -- OAOWFC
GL071214+184901 108.0576 18.8171 132.0515 -- 17.8 -- OAOWFC
GL071242+142548 108.1734 14.4301 122.0519 20.3 -- 19.0 Kanata-HONIR
GL072527+130403 111.3637 13.0676 147.6425 15.7 -- 14.5 Kanata-HONIR
GL071150+190004 107.9573 19.0012 183.6792 -- 17.8 -- OAOWFC
GL071311+134507 108.2944 13.7519 169.5679 20.3 -- 19.1 Kanata-HONIR
GL071553+120654 108.969 12.1149 30.1852 -- -- 19.0 Kanata-HONIR
GL072540+120523 111.4156 12.0898 132.9442 16.9 -- 15.9 Kanata-HONIR
GL071105+144312 107.7713 14.7201 150.29 20.7 -- 19.3 Kanata-HONIR
GL072557+120332 111.4872 12.0589 132.9218 16.9 -- -- Kanata-HONIR
GL071726+124102 109.3597 12.6838 178.0517 20.4 -- 19.3 Kanata-HONIR
Kanata-HONIR: 150 cm Kanata telescope at Higashi-Hiroshima Observatory and HONIR -- a 2 channel imager (Rc and H or J) (Akitaya et al. 2014, Proc. SPIE 9147, 91474O)
Nayuta-NIC: 200 cm Nayuta telescope at Nishi-Harima Astronomical Observatory and Nishiharima Infrared Camera, NIC (J, H, Ks)
OAOWFC: 91 cm Okayama Astrophysical Observatory NIR Wide Field Camera, OAOWFC (J) (Yanagisawa et al., 2019, PASJ, 71, 118)
GCN Circular 26796
Subject
LIGO/Virgo S200114f: ZTF Forced Photometry of the Swift Source S200114f_X2
Date
2020-01-17T06:19:19Z (6 years ago)
From
Igor Andreoni at Caltech <igor.andreoni@gmail.com>
Igor Andreoni (Caltech), Mansi M. Kasliwal (Caltech), Matthew Graham (Caltech), Frank Masci (IPAC)
On behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations
The Zwicky Transient Facility (ZTF; Graham et al. 2019, Bellm et al. 2019) has repeatidly observed the location of Source S200114f_X2 (Evans et al., GCN #26787, GCN #26791), an X-ray transient candidate possibly associated with the gravitational wave event S200114f (LVC, GCN #26734). We used the Kowalski infrastructure (Duev et al., 2019) to query the ZTF database. Only one source, ZTF19aaehfwn, was found in ZTF data that generated >5sigma alerts within a 21-arcsec radius from Source S200114f_X2, whose position was reported with 7 arcsec uncertainty (Evans et al., GCN #26787, GCN #26791). ZTF19aaehfwn is spatially coincident with the candidate quasar WISEA J072127.41+170205.7 (Assef et al., 2018), that is consistent with the location of Source S200114f_X2 as previously noted by Evans et al. (GCN #26787, GCN #26791). ZTF19aaehfwn/WISEA J072127.41+170205.7 is located 3.9 arcsec away from Source S200114f_X2.
We performed forced photometry on 57 ZTF images acquired between 2018-11-17 and 2020-01-14 08:23:13, with the last image taken about 6 hours after the S200114f detection time. Forced photometry was performed on images processed through the ZTF reduction and image subtraction pipelines at IPAC (Masci et al. 2019).
The light curve of ZTF19aaehfwn shows possible long and short timescale variability, with upper limits at about r>20 before September 2019, followed by several detections at roughly 19.5 < r < 20.5 and 19.6 < g < 20.1. The light curve behavior does not appear atypical for an AGN and there is no evidence of strong flares. A decline in brightness is measured in the first hours after S200114f, as shown in the table below presenting the latest data points available.
+---------------------+--------+----------+------+
| Date (UTC) | filter | mag (AB) | err |
+---------------------+--------+----------+------+
| 2020-01-12 07:51:20 | r | 19.52 | 0.19 |
| 2020-01-14 08:22:34 | r | 19.70 | 0.11 |
| 2020-01-14 08:23:13 | r | 20.28 | 0.18 |
+---------------------+--------+----------+------+
The ZTF forced-photometry service was funded under the Heising-Simons Foundation grant #12540303 (PI: Graham). 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.
GCN Circular 26793
Subject
LIGO/Virgo S200114f: Upper Limits from Wide-Field Infrared Search with Palomar Gattini-IR
Date
2020-01-17T00:06:21Z (6 years ago)
From
Matthew Hankins at Caltech <mhankins@caltech.edu>
K. De (Caltech), M. Hankins (Caltech), M. Coughlin (Caltech), M. M. Kasliwal (Caltech), S. M. Adams (Caltech), I. Andreoni (Caltech), S. Anand (Caltech), M. Sharma (Caltech), L. Singer (NASA GSFC), T. Ahumada (UMD), A. Moore (ANU), J. Soon (ANU), M. Ashley (UNSW), T. Travouillon (ANU), R. Soria (NAOC) report on behalf of the Palomar Gattini-IR team and the larger GROWTH (Global Relay of Observatories Watching Transients Happen) collaboration
We report wide-field near-infrared follow-up observations of the localization region of the gravitational wave event S200114f (GCN 26734) by the Palomar Gattini-IR survey (Moore and Kasliwal 2019). Gattini-IR is a newly commissioned near-IR camera with a field of view of 25 square degrees mounted on a robotic 30 cm telescope at Palomar observatory (De et al. 2020).
We started customized Target of Opportunity observations at UT 2020-01-14 05:02. The tiling was optimally determined and triggered using the GROWTH Target of Opportunity marshal (Coughlin et al. 2019a, Kasliwal et al. 2019b). We imaged a total of 479 square degrees, covering 89.1% of the probability region of the event until UT 11:21. We obtained a second epoch of observations starting the next night at at UT 2019-01-15 02:03 and continuing until UT 07:59. All data were processed and stacked with the Palomar Gattini-IR data reduction pipeline. The typical limiting magnitude of each field visit (300s second exposure time) was between 15.9 and 16.3 AB mag in J-band. No viable counterparts with at least two detections and without previous history of variability were identified in the single epoch stacks within the survey region.
GCN Circular 26791
Subject
LIGO/Virgo S200114f: Possible X-ray transient
Date
2020-01-16T19:14:59Z (6 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P.A. Evans (U. Leicester), J.A. Kennea (PSU), A. Tohuvavohu (U.
Toronto), S.D. Barthelmy (NASA/GSFC), A.P. Beardmore (U. Leicester),
M.G. Bernardini (INAF-OAB), A.A. Breeveld (UCL-MSSL), P. Brown (TAMU),
D.N. Burrows (PSU), S. Campana (INAF-OAB), S.B. Cenko (NASA/GSFC), G.
Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB),
V. D'Elia(ASDC), S.W.K. Emery (UCL-MSSL), P. Giommi (ASI), C. Gronwall
(PSU), D. Hartmann (U. Clemson), H.A. Krimm (CRESST/GSFC/USRA), N.J.
Klingler (PSU), N.P.M. Kuin (UCL-MSSL), A.Y. Lien (GSFC/UMBC), F.E.
Marshall (NASA/GSFC), A. Melandri (INAF-OAB), J.A. Nousek (PSU), S.R.
Oates (U. 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), D.M. Palmer (LANL), M. Perri (ASDC), J.L. Racusin
(NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU), M.H. Siegel (PSU), G.
Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/UMCP) report on behalf of
the Swift team:
We have carried out further observations of the rank 2 source (referred to as Source 2) in GCN 26787. This source,hereafter, Source S200114f_X2 has not faded between our observations, however it is detected with a 0.3-10 keV count rate of 0.069 +/- 0.0064 ct/sec.
A spectrum created from the recent XRT data can be modelled with a power-law with photon index 1.4 (+0.4, -0.3). Using this model, a 3-sigma RASS upper limit at this location translates to 0.038 ct/sec in XRT. The recent detectionis therefore nearly 5-sigma above the upper limit from RASS, accounting for the spectral shape.
As reported in GCN 26787, this source is positionally coincident with a candidate AGN, and therefore this rise in flux may indicate nothing more than AGN activity, however it could also indicate a transient source occuring in the AGN. Our position uncertainty does not allow us to confirm whether this source is in the nuclear of the WISE galaxy.
Further observations are therefore strongly encouraged.
The source position is
RA: 110.3641 ( = 07h 21m 27.38s) J2000
Dec: +17.0360 ( = +17d 02' 09.6") J2000
Error: 7.0 arcsec, (radius, 90% confidence).
GCN Circular 26787
Subject
LIGO/Virgo S200114f: Swift-XRT sources and observations
Date
2020-01-16T14:39:16Z (6 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P.A. Evans (U. Leicester), J.A. Kennea (PSU), A. Tohuvavohu (U.
Toronto), S.D. Barthelmy (NASA/GSFC), A.P. Beardmore (U. Leicester),
M.G. Bernardini (INAF-OAB), A.A. Breeveld (UCL-MSSL), P. Brown (TAMU),
D.N. Burrows (PSU), S. Campana (INAF-OAB), S.B. Cenko (NASA/GSFC), G.
Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB),
V. D'Elia(ASDC), S.W.K. Emery (UCL-MSSL), P. Giommi (ASI), C. Gronwall
(PSU), D. Hartmann (U. Clemson), H.A. Krimm (CRESST/GSFC/USRA), N.J.
Klingler (PSU), N.P.M. Kuin (UCL-MSSL), A.Y. Lien (GSFC/UMBC), F.E.
Marshall (NASA/GSFC), A. Melandri (INAF-OAB), J.A. Nousek (PSU), S.R.
Oates (U. 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), D.M. Palmer (LANL), M. Perri (ASDC), J.L. Racusin
(NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU), M.H. Siegel (PSU), G.
Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/UMCP) report on behalf of
the Swift team:
Swift has carried out 206 observations of the LVC error region for the
GW trigger S200114f following the 'cWB' (version 3) GW localisation
map. The observations currently span from 6.6 ks to 99 ks after the LVC
trigger, and the XRT has covered 22.3 deg^2 on the sky (corrected for
overlaps). This covers 30% of the probability in the 'cWB' (version 3)
skymap. These pointings and associated metadata have been reported to
the Treasure Map (Wyatt et al., arXiv 2001.00588;
http://treasuremap.space/alerts?graceids=S200114f).
A 'rank 2' source has been found, so classified because it shows
indications of fading, however it is spatially consistent with a source
in the WISE AGN candidates catalogs (Assef et al., 2018) and therefore
may simply be a variable AGN. The details of this source are:
Source 2:
=============
RA: 110.3641 ( = 07h 21m 27.38s) J2000
Dec: +17.0360 ( = +17d 02' 09.6") J2000
Error: 7.0 (arcsec, radius, 90% confidence).
Peak Rate: 9.6e-02 +/- 1.7e-02 ct/sec (0.3-10 keV)
Peak Flux: 4.1e-12 +/- 7.5e-13 erg cm^-2 s^-1 (0.3-10 keV)
Catalogued: No
RASS UL: 3.5e-02 ct/sec, 3-sigma, converted to XRT (0.3-10 keV)
Further observations of this source are scheduled.
In total, we have detected 8 X-ray sources. Each source is assigned a
rank of 1-4 which describes how likely it is to be related to the GW
trigger, with 1 being the most likely and 4 being the least likely. The
ranks are described at https://www.swift.ac.uk/ranks.php.
We have found:
* 0 sources of rank 1
* 1 source of rank 2
* 6 sources of rank 3
* 1 source of rank 4
RANK 3 sources
==============
These are uncatalogued X-ray sources, however they are not brighter
than previous upper limits, so do not stand out as likely counterparts
to the GW trigger.
| Source ID | RA | Dec | Err90 |
| S200114f_X1 | 07h 13m 48.09s | +23d 04' 50.5" | 7.5" |
| S200114f_X10 | 03h 41m 58.28s | -25d 24' 17.6" | 6.1" |
| S200114f_X46 | 03h 41m 1.50s | -25d 26' 54.4" | 6.4" |
| S200114f_X56 | 07h 22m 51.63s | +16d 15' 51.0" | 6.3" |
| S200114f_X57 | 07h 23m 54.09s | +16d 22' 00.1" | 7.7" |
| S200114f_X58 | 07h 23m 50.42s | +16d 21' 17.1" | 6.7" |
RANK 4 sources
==============
These are catalogued X-ray sources, showing no signs of outburst
compared to previous observations, so they are not likely to be related
to the GW trigger.
| Source ID | RA | Dec | Err90 |
| S200114f_X59 | 07h 15m 9.23s | +15d 55' 36.9" | 8.3" |
The Swift-XRT observations also covered the locations of 6 sources
reported by other observers, thus:
* AT2020vr (GCN26741) F < 3.3x10^-12 erg cm^-2 s^-1.
* AT2020vs (GCN26741