apjThe Astrophysical JournalAPJAstrophys. J.0004-637X1538-4357The American Astronomical Societyapjac5b6010.3847/1538-4357/ac5b60ac5b60AAS35017330High-Energy Phenomena and Fundamental PhysicsSOAR/Goodman Spectroscopic Assessment of Candidate Counterparts of the LIGO/Virgo Event GW190814*

Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, Inovações e Comunicações (MCTIC) do Brasil, the US National Science Foundations National Optical–Infrared Astronomy Research Laboratory (NOIRLab), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU).

0000-0001-7211-5729TuckerD. L.1dtucker@fnal.gov0000-0001-8653-7738WiesnerM. P.20000-0002-7069-7857AllamS. S.10000-0001-6082-8529Soares-SantosM.30000-0003-4383-2969BomC. R.45ButnerM.60000-0001-9578-6322GarciaA.30000-0002-7016-5471MorganR.780000-0002-5115-6377Olivares E.F.90000-0002-6011-0530PalmeseA.1100000-0003-3402-6164Santana-SilvaL.110000-0002-2854-6713ShrivastavaA.30000-0002-0609-3987AnnisJ.10000-0002-9370-8360García-BellidoJ.120000-0003-2524-5154GillM. S. S.130000-0001-6718-2978HernerK.1KilpatrickC. D.140000-0003-2206-2651MaklerM.415ShermanN.3AmaraA.160000-0002-7825-3206LinH.10000-0002-3321-1432SmithM.17SwannE.170000-0001-7090-4898ArcaviI.1819BachmannT. G.200000-0001-8156-0429BechtolK.2122BerlfeinF.230000-0001-7124-4094BriceñoC.240000-0001-5201-8374BroutD.25260000-0003-2789-3817ButlerR. E.27CartierR.240000-0001-5031-0128CasaresJ.28290000-0001-5403-3762ChenH.-Y.300000-0003-1949-7638ConseliceC.31ContrerasC.32CookE.330000-0001-5703-2108CookeJ.34350000-0002-8532-4025DageK.36D’AndreaC.370000-0002-4213-8783DavisT. M.38de CarvalhoR.110000-0002-8357-7467DiehlH. T.10000-0002-8134-9591DietrichJ. P.390000-0002-2077-4914DoctorZ.100000-0001-8251-933XDrlica-WagnerA.110200000-0001-7081-0082DroutM.40FarrB.410000-0003-3870-8445FinleyD. A.10000-0002-1980-5293FishbachM.200000-0002-2445-5275FoleyR. J.42Förster-BurónF.430000-0002-1510-5214FosalbaP.4445FriedelD.460000-0003-4079-3263FriemanJ.1100000-0001-9553-4723FrohmaierC.160000-0002-4588-6517GruendlR. A.4748HartleyW. G.490000-0002-1125-9187HiramatsuD.50510000-0002-0175-5064HolzD. E.100000-0003-4253-656XHowellD. A.50520000-0003-0071-1622KawashA.530000-0003-3221-0419KesslerR.10200000-0003-2511-0946KuropatkinN.1LahavO.54LundgrenA.160000-0001-9589-3793LundquistM.55MalikU.560000-0003-3654-1602MannA. W.570000-0001-9359-6752MarrinerJ.10000-0003-0710-9474MarshallJ. L.330000-0002-9144-7726Martínez-VázquezC. E.240000-0001-5807-7893McCullyC.500000-0002-1372-2534MenanteauF.4748MezaN.58NarayanG.480000-0002-7357-0317NeilsenE.10000-0001-7474-0544NicolaouC.54NicholR.160000-0003-1339-2683Paz-ChinchónF.4759PereiraM. E. S.60PinedaJ.61620000-0002-4596-1337PointsS.24Quirola-VásquezJ.6364RemboldS.650000-0002-4410-5387RestA.32660000-0001-8651-8772RodriguezÓ.1861620000-0002-9328-879XRomerA. K.670000-0003-2764-7093SakoM.250000-0003-2342-7501SalimS.27ScolnicD.680000-0002-6261-4601SmithJ. A.690000-0002-1468-9668StraderJ.530000-0001-9053-4820SullivanM.170000-0002-1488-8552SwansonM. E. C.470000-0002-6325-5671ThomasD.160000-0001-8818-0795ValentiS.70VargaT. N.71720000-0002-7123-8943WalkerA. R.730000-0002-8282-2010WellerJ.71720000-0001-7336-7725WoodM. L.570000-0002-9541-2678YannyB.1ZentenoA.240000-0001-5679-6747AguenaM.74Andrade-OliveiraF.74750000-0002-3602-3664BertinE.76770000-0002-8458-5047BrooksD.54BurkeD. L.13780000-0003-3044-5150RosellA. Carnero740000-0002-4802-3194KindM. Carrasco47480000-0002-3130-0204CarreteroJ.790000-0001-8158-1449CostanziM.808182da CostaL. N.74830000-0001-8318-6813De VicenteJ.840000-0002-0466-3288DesaiS.85EverettS.860000-0002-1295-1132FerreroI.870000-0002-2367-5049FlaugherB.10000-0001-9632-0815GaztanagaE.44450000-0001-6942-2736GerdesD. W.3880000-0003-3270-7644GruenD.390000-0003-3023-8362GschwendJ.74830000-0003-0825-0517GutierrezG.10000-0003-2071-9349HintonS. R.380000-0002-9369-4157HollowoodD. L.860000-0002-6550-2023HonscheidK.89900000-0001-5160-4486JamesD. J.910000-0003-0120-0808KuehnK.9293LimaM.74940000-0001-9856-9307MaiaM. A. G.74830000-0002-6610-4836MiquelR.79950000-0003-2120-1154OgandoR. L. C.830000-0001-9186-6042PieresA.74830000-0002-2598-0514Plazas MalagónA. A.96Rodriguez-MonroyM.840000-0002-9646-8198SanchezE.84ScarpineV.10000-0001-9504-2059SchubnellM.30000-0002-0211-2861SerranoS.44450000-0002-1831-1953Sevilla-NoarbeI.840000-0002-7047-9358SuchytaE.970000-0003-1704-0781TarleG.30000-0001-7836-2261ToC.137898ZhangY.1 (DES Collaboration) Fermi National Accelerator Laboratory, P.O. 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The Author(s). Published by the American Astronomical Society.2022 Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.Abstract

On 2019 August 14 at 21:10:39 UTC, the LIGO/Virgo Collaboration (LVC) detected a possible neutron star–black hole merger (NSBH), the first ever identified. An extensive search for an optical counterpart of this event, designated GW190814, was undertaken using the Dark Energy Camera on the 4 m Victor M. Blanco Telescope at the Cerro Tololo Inter-American Observatory. Target of Opportunity interrupts were issued on eight separate nights to observe 11 candidates using the 4.1 m Southern Astrophysical Research (SOAR) telescope’s Goodman High Throughput Spectrograph in order to assess whether any of these transients was likely to be an optical counterpart of the possible NSBH merger. Here, we describe the process of observing with SOAR, the analysis of our spectra, our spectroscopic typing methodology, and our resultant conclusion that none of the candidates corresponded to the gravitational wave merger event but were all instead other transients. Finally, we describe the lessons learned from this effort. Application of these lessons will be critical for a successful community spectroscopic follow-up program for LVC observing run 4 (O4) and beyond.

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