Variable hot subdwarf from Gaia DR2 and TESS J/ApJ/928/20 ivo://CDS.VizieR/J/ApJ/928/20 doi:10.26093/cds/vizier.19280020 CDS Barlow B.N. Corcoran K.A. Parker I.M. Kupfer T. Nemeth P.,Hermes J.J. Lopez I.D. Frondorf W.J. Vestal D. Holden J. 2024-11-06T20:24:29Z 2024-02-27T10:52:18Z CDS support team CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France cds-question@unistra.fr subdwarf-stars variable-stars two-color-diagrams visible-astronomy absolute-magnitude Hot subdwarf stars are mostly stripped red giants that can exhibit photometric variations due to stellar pulsations, eclipses, the reflection effect, ellipsoidal modulation, and Doppler beaming. Detailed studies of their light curves help constrain stellar parameters through asteroseismological analyses or binary light-curve modeling and generally improve our capacity to draw a statistically meaningful picture of this enigmatic stage of stellar evolution. From an analysis of Gaia DR2 flux errors, we have identified around 1200 candidate hot subdwarfs with inflated flux errors for their magnitudes-a strong indicator of photometric variability. As a pilot study, we obtained 2 minute cadence TESS Cycle 2 observations of 187 candidate hot subdwarfs with anomalous Gaia flux errors. More than 90% of our targets show significant photometric variations in their TESS light curves. Many of the new systems found are cataclysmic variables, but we report the discovery of several new variable hot subdwarfs, including HW Vir binaries, reflection-effect systems, pulsating sdBVs stars, and ellipsoidally modulated systems. We determine atmospheric parameters for select systems using follow-up spectroscopy from the 3m Shane telescope. Finally, we present a Fourier diagnostic plot for classifying binary light curves using the relative amplitudes and phases of their fundamental and harmonic signals in their periodograms. This plot makes it possible to identify certain types of variables efficiently, without directly investigating their light curves, and may assist in the rapid classification of systems observed in large photometric surveys. 2022ApJ...928...20B https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/928/20 Catalog Research IsServedBy TAP VizieR generic service IsServedBy Conesearch service related-to B/cb : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2004) II/207 : Palomar-Green catalog UV-excess stellar objects (Green+ 1986) I/276 : Tycho Double Star Catalogue (TDSC) (Fabricius+ 2002) V/110 : Catalog of Cataclysmic Variables (Downes+ 2001) V/113 : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003) V/123 : Catalog of Cataclysmic Variables (Downes+ 2001-2006) I/345 : Gaia DR2 (Gaia Collaboration, 2018) I/358 : Gaia DR3 Part 4. Variability (Gaia Collaboration, 2022) J/ApJS/61/569 : KPD UV-excess objects (Downes+, 1986) J/AJ/119/1901 : ROTSE all-sky surveys for variable stars (Akerlof+, 2000) J/A+A/400/939 : Stellar parameters of 115 HQS sdB stars (Edelmann+, 2003) J/A+A/513/A6 : NOT survey of subdwarf B stars (Ostensen+, 2010) J/A+A/546/A69 : Orbits of visual binaries & dynamical masses (Malkov+, 2012) J/MNRAS/427/2180 : GALEX survey subdwarf atmospheric parameters (Nemeth+, 2012) J/MNRAS/457/3396 : New hot subdwarf stars (Perez-Fernandez+, 2016) J/ApJ/845/171 : Rapidly pulsating sdB stars with GALEX (Boudreaux+, 2017) J/AJ/153/204 : RR Lyrae stars from the PS1 3{pi} survey (Sesar+, 2017) J/ApJS/238/25 : UV var. with GALEX gPhoton archive. I. (de la Vega+, 2018) J/AJ/156/241 : Variable stars measured by ATLAS (Heinze+, 2018) J/MNRAS/485/3457 : Rotational modulation in TESS B stars (Balona+, 2019) J/A+A/623/A110 : Gaia DR2. Variable stars in CMD (Gaia Collaboration+, 2019) J/A+A/621/A38 : Gaia catalogue of hot subluminous stars (Geier+, 2019) J/A+A/630/A80 : EREBOS project. I. (Schaffenroth+, 2019) J/MNRAS/492/L40 : Disentangling cataclysmic var. in Gaia DR2 (Abril+, 2020) J/ApJS/250/20 : Rot. periods in TESS objects of interest (Canto+, 2020) J/A+A/635/A193 : Catalogue of hot subdwarf stars DR2 (Geier, 2020) J/ApJ/912/125 : Variable white dwarfs from Gaia & ZTF phot. (Guidry+, 2021) https://cds.unistra.fr/vizier-org/licences_vizier.html https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/928/20 https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/928/20 http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/928/20 https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/928/20 https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/928/20 http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/928/20 GET text/xml+votable https://tapvizier.cds.unistra.fr/TAPVizieR/tap Cone search capability for table J/ApJ/928/20/table1 (Known and candidate hot subdwarf stars from the Geier+ 2019, J/A+A/621/A38 catalog with the highest varindex values, arranged from highest to lowest varindex values) https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/928/20/table1? https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/928/20/table1? http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/928/20/table1? GET text/xml+votable 180.0 50000 true 239.5537775 -66.4043057 0.005555555555555556 Cone search capability for table J/ApJ/928/20/table5 (Summary of results from our TESS Cycle 2 survey of candidate variable hot subdwarf stars) https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/928/20/table5? https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/928/20/table5? http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/928/20/table5? GET text/xml+votable 180.0 50000 true 285.7575828 42.5461492 0.005555555555555556 5/11967 6/414 781 901 1109 1115 1397 1399 1470 1671 1685 1772 2033 2073 2154 2240-2241 2253 2341 2427 2437 2544 2619 2674 2686 2702 2704 2715 2731 2742 2753 2781 2793 2806 2855 2859 2906-2907 2994 3030 3083 3091-3092 3139 3410 3440 3541 3583 3815 3923 3959 4011 4014 4040 4110 4298 4336 4757 4990 5019 5129 5493 5522 5567 5650 5715 5809 5843 5883 5908 5982 6015 6075 6284 6314 6318-6319 6324 6340 6347 6408 6456 6546 6670 6694 6711 6713 6738 6784 6902 6972-6973 7027 7038 7046 7100 7210 7306 7534 7577 7812 7830 7884 7893 7906 7933 8006 8042 8056 8068 8425 8505 8596 8719 8977 9436 9484 9555 9578 9666 9672 9774-9775 9998 10024 10226 10285 10330 10336 10434 10439 10624 10799 10872 10973 11084 11140 11250 11354 11402 11485 11540 11743 11769 11802 11820 12048 12135 12186 12328 12334 12419 12523 12554 12568 12725 12782 12835 12850 12854 12876 12885 12888 12896 12900 12921 12923 12936 12938 12945 12971 12975 12997 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J/ApJ/928/20/table1 Known and candidate hot subdwarf stars from the Geier+ 2019, J/A+A/621/A38 catalog with the highest varindex values, arranged from highest to lowest varindex values Simbad Simbad column added by the CDS meta.ref.url char recno Record number assigned by the VizieR team. Should Not be used for identification. meta.record int TESS Display the TESS results (link to Table 2) meta.ref.url char GaiaDR2 Gaia DR2 identifier meta.id;meta.main primary Alias Alternative target name meta.id char RAJ2000 Gaia DR2 Right Ascension (J2000) deg pos.eq.ra;meta.main DEJ2000 Gaia DR2 Declination (J2000) deg pos.eq.dec;meta.main Gmag [2.68/19] Gaia DR2 apparent G magnitude mag phot.mag;em.opt float GMAG [-2.3/11.8]? Gaia DR2 absolute G magnitude mag phys.magAbs;em.opt float nullable BP-RP [-3.2/0.6] Gaia DR2 GBP-GRP color mag phot.color;em.opt.B;em.opt.R float VG [0.028/1.2] Gaia variability metric (1) src.var.index float varindex [0.02/1.1] Gaia variability index (2) meta.code;src.var.index float G19 Display data from Geier+ 2019, J/A+A/621/A38 meta.ref.url char
J/ApJ/928/20/table5 Summary of results from our TESS Cycle 2 survey of candidate variable hot subdwarf stars GaiaDR2 Gaia DR2 Identifier meta.id;meta.main Simbad Simbad column added by the CDS meta.ref.url char recno Record number assigned by the VizieR team. Should Not be used for identification. meta.record int TIC [4738707/2046417955] TESS Input Catalog ID meta.id.cross long Alias Alternative name for target meta.id char Period [0.005/5.3]? Period of binary system or dominant mode in multimode system d time.period double nullable Type Classification type meta.code;src.var char _RA Right Ascension (J2000) from SIMBAD (not part of the original data) deg pos.eq.ra;meta.main _DE Declination (J2000) from SIMBAD (not part of the original data) deg pos.eq.dec;meta.main