A search for variable subdwarf B stars in TESS Full Frame Images II. Variable objects in the northern ecliptic hemisphere

Abstract

We report the results of our search for pulsating subdwarf B stars in Full Frame Images collected during Year 2 of the TESS mission and covering the northern ecliptic hemisphere. This is a continuation of our effort we presented in Paper I. We found 13 likely new pulsating subdwarf B stars, 10 pulsating candidates that are identified as other hot subdwarfs, and 30 spectroscopically unclassified objects that show amplitude spectra typical of pulsating subdwarf B stars. We found 506 variable objects, most of them spectroscopically unclassified, hence their specific variability class yet to be confirmed. Eclipsing binaries with sharp eclipses sample comprises 33 systems. For 12 of them we derived precise orbital periods and checked their stabilities. We identified one known and five new candidate HW Vir systems. The amplitude spectra of the 13 likely sdB pulsators are not rich in modes, hence any further analysis is not possible. However, we selected three candidates for pulsating subdwarf B stars that show the richest amplitude spectra and we performed a mode identification deriving modal degrees of most of the detected modes. In total, in both ecliptic hemispheres, we found 15 likely pulsating pulsating subdwarf B stars, additional 10 candidates for pulsating subdwarf B stars, 66 other variable subdwarf B stars, 2076 spectroscopically unconfirmed variable stars, and 123 variable non-sdB stars.

arXiv commentpublished in MNRAS

References in corpus (15)

• The SIMBAD astronomical database
• The Catalina Surveys Periodic Variable Star Catalog
• Rotation and differential rotation of active Kepler stars
• Hot subluminous stars
• eleanor: An open-source tool for extracting light curves from the TESS Full-Frame Images
• A detection threshold in the amplitude spectra calculated from Kepler data obtained during K2 mission
• Population of hot subdwarf stars studied with Gaia III. Catalogue of known hot subdwarf stars: Data Release 2
• First Kepler results on compact pulsators VI. Targets in the final half of the survey phase
• First Kepler results on compact pulsators VIII: Mode identifications via period spacings in $g-$mode pulsating Subdwarf B stars
• A pulsation zoo in the hot subdwarf B star KIC 10139564 observed by Kepler
• The pulsating hot subdwarf Balloon 090100001: results of the 2005 multisite campaign
• Observations and asteroseismological analysis of the rapid subdwarf B pulsator EC 09582-1137
• A search for variable subdwarf B stars in TESS Full Frame Images -- I. Variable objects in the southern ecliptic hemisphere
• Spectroscopic identifications of blue H-alpha excess sources in the Kepler field-of-view
• Three new pulsating sdB stars discovered with SuperWASP

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• TESS Eclipsing Binary Stars. I. Short cadence observations of 4584 eclipsing binaries in Sectors 1-26
• TESS-Gaia Light Curve: a PSF-based TESS FFI light curve product
• Hot subdwarfs in close binaries observed from space I: orbital, atmospheric, and absolute parameters and the nature of their companions
• Data mining techniques on astronomical spectra data. II : Classification Analysis
• FX UMa: A New Heartbeat Binary System with Linear and Non-linear Tidal Oscillations and delta Sct Pulsations
• Physical Properties of 29 sdB+dM Eclipsing Binaries in Zwicky Transient Facility
• Short-Period Variables in TESS Full-Frame Image Light Curves Identified via Convolutional Neural Networks
• A search for variable subdwarf B stars in TESS Full Frame Images III. An update on variable targets in both ecliptic hemispheres -- contamination analysis and new sdB pulsators
• Identifying and characterising the population of hot sub-luminous stars with multi-colour MeerLICHT data
• Discovery of periodic variables in the hot subdwarf catalogue through a systematic search in Zwicky Transient Facility data
• Onset of common envelope evolution during a core helium flash by rapid envelope expansion
• Searching for white dwarf variables in TESS data