[vsnet-grb-info 24731] LIGO/Virgo S200114f: SOAR spectroscopy of AT2020zf, AT2020ace and AT2020ach

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26830
SUBJECT: LIGO/Virgo S200114f: SOAR spectroscopy of AT2020zf, AT2020ace and AT2020ach
DATE:    20/01/20 23:14:54 GMT
FROM:    Felipe Olivares E. at Millennium Institute of Astrophysics  <felipe204 at gmail.com>

Regis Cartier (CTIO/OIR lab), Felipe Olivares (INCT/UDA), Ósmar Rodríguez
(UNAB), Nicolás 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 Pachón. 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 Autónoma 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).