J/ApJ/918/63ivo://CDS.VizieR/J/ApJ/918/63doi:10.26093/cds/vizier.19180063CDSAndreoni I.Coughlin M.W.Kool E.C.Kasliwal M.M.Kumar H.,Bhalerao V.Carracedo A.S.Ho A.Y.Q.Pang P.T.H.Saraogi D.Sharma K.,Shenoy V.Burns E.Ahumada T.Anand S.Singer L.P.Perley D.A.De K.,Fremling U.C.Bellm E.C.Bulla M.Crellin-quick A.Dietrich T.,Drake A.Duev D.A.Goobar A.Graham M.J.Kaplan D.L.Kulkarni S.R.,Laher R.R.Mahabal A.A.Shupe D.L.Sollerman J.Walters R.Yao Y.2023-06-15T09:24:59Z2023-04-04T10:17:28ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frphotometryvisible-astronomyredshiftedgamma-ray-astronomygamma-ray-burstsnovaetransient-sourcesThe most common way to discover extragalactic fast transients, which fade within a few nights in the optical, is via follow-up of gamma-ray burst and gravitational-wave triggers. However, wide-field surveys have the potential to identify rapidly fading transients independently of such external triggers. The volumetric survey speed of the Zwicky Transient Facility (ZTF) makes it sensitive to objects as faint and fast fading as kilonovae, the optical counterparts to binary neutron star mergers, out to almost 200 Mpc. We introduce an open-source software infrastructure, the ZTF REaltime Search and Triggering, ZTFReST, designed to identify kilonovae and fast transients in ZTF data. Using the ZTF alert stream combined with forced point-spread-function photometry, we have implemented automated candidate ranking based on their photometric evolution and fitting to kilonova models. Automated triggering, with a human in the loop for monitoring, of follow-up systems has also been implemented. In 13 months of science validation, we found several extragalactic fast transients independently of any external trigger, including two supernovae with post-shock cooling emission, two known afterglows with an associated gamma-ray burst (ZTF20abbiixp, ZTF20abwysqy), two known afterglows without any known gamma-ray counterpart (ZTF20aajnksq, ZTF21aaeyldq), and three new fast-declining sources (ZTF20abtxwfx, ZTF20acozryr, ZTF21aagwbjr) that are likely associated with GRB200817A, GRB201103B, and GRB210204A. However, we have not found any objects that appear to be kilonovae. We constrain the rate of GW170817-like kilonovae to R<900Gpc^-3^/yr (95% confidence). A framework such as ZTFReST could become a prime tool for kilonova and fast-transient discovery with the Vera Rubin Observatory.2021ApJ...918...63Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/918/63CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/281 : GLADE v2.3 catalog (Dalya+, 2018)J/ApJ/746/156 : Radio afterglow observations of GRBs (Chandra+, 2012)J/ApJS/200/8 : AGES: the AGN and Galaxy Evolution Survey (Kochanek+, 2012)J/ApJ/806/52 : 8 Fermi GRB afterglows follow-up (Singer+, 2015)J/ApJ/818/110 : Short GRBs with Fermi GBM and Swift BAT (Burns+, 2016)J/ApJ/828/36 : GRB light-curve decay indices with Swift (Del Vecchio+, 2016)J/A+A/593/A68 : PTF12os & iPTF13bvn spectra and light curves (Fremling+, 2016)J/ApJ/848/L29 : Opt. follow-up of GW170817 counterpart (Diaz+, 2017)J/ApJ/880/7 : The Local Universe survey. I. CLU-Halpha (Cook+, 2019)J/ApJ/884/L55 : Opt. follow-up of gal. within S190814bv region (Gomez+, 2019)J/A+A/631/A147 : Transient processing and analysis using AMPEL (Nordin+, 2019)J/ApJ/886/152 : ZTF early observations of Type Ia SNe. I. LCs (Yao+, 2019)J/A+A/643/A113 : iz photometry of S190814bv ctp candidates (Ackley+, 2020)J/ApJ/890/131 : Follow-up of cand. counterparts of S190814bv (Andreoni+, 2020)J/ApJ/904/155 : gri photometry for 32 kilonovae with ZTF (Andreoni+, 2020)J/ApJ/905/58 : The local universe with ZTF. I. Transients (De+, 2020)J/ApJ/895/32 : Zwicky Transient Facility BTS. I. (Fremling+, 2020)J/ApJ/905/98 : Keck/LRIS optical spectrum of ZTF20aajnksq (Ho+, 2020)J/ApJ/905/145 : ZTF cand. counterparts to 13 GW follow-up (Kasliwal+, 2020)http://www.wis-tns.org/ : Transient Name Server home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/918/63https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/918/63http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/918/63https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/918/63https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/918/63http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/918/63GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/918/63/table1 (Afterglows found with ZTFReST during science validation)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/918/63/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/918/63/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/918/63/table1?GETtext/xml+votable180.050000true191.770291745.2006250.0055555555555555566/224 999 2154 2708 5882 10166 10512 10960 11799 20349 21775 22392https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/918/63?format=asciiGamma-rayOpticaldefaultJ/ApJ/918/63/table1Afterglows found with ZTFReST during science validationNameZTF name of the sourcemeta.id;meta.maincharprimaryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_NameFlag(s) on Name (1)meta.codecharTNSTransient Name Server denominationmeta.idcharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainGLAT[-41.5/71.9] Galactic latitudedegpos.galactic.latfloatClassClassification, or associated GRB when knownsrc.classcharz[0.03/2.9]? Redshiftsrc.redshiftfloatnullableTWDiscovery reference (This work)meta.bibcharRefOther discovery reference(s) (2)meta.ref;pos.framechargFade[0.29/2.01]? Fade rate at the time of discovery in the g band (3)phot.flux;arith.ratio;em.opt.BfloatnullablerFade[0.28/17.56]? Fade rate at the time of discovery in the r band (3)phot.flux;arith.ratio;em.opt.RfloatnullableNpNumber of photometric measurements for this source (link to Fig3+4+7)meta.numberintnullableLCInteractive Plotmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJ/918/63/fig347Forced PSF photometry light curves of the 5 fast transients (from Figures 3, 4 and 7)JDJulian datedtime.epochcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameZTF name of the sourcemeta.id;meta.maincharInstInstrument used (1)instr.setupcharObsObserved UTC date, ISO 8601 (2)stime.epochnullableomag[17.16/23.95]? Observed AB magnitude in Filtmagphot.magfloatnullablee_omag[0.03/0.4]? Uncertainty in omagmagstat.error;phot.magfloatnullableLimOmag[17.3/25.6]? Limiting magnitude, AB systemmagphot.mag;stat.maxfloatnullableFilt[griJ] Filtermeta.id;instr.filterchar