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 (7 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 (7 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 (7 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 (7 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 (7 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 (7 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