J/A+A/699/A337ivo://CDS.VizieR/J/A+A/699/A337doi:10.26093/cds/vizier.36990337CDSPerger K.Seli B.Vida K.2025-08-11T20:02:11Z2025-07-17T13:03:11ZCDS support team

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

cds-question@unistra.frbrown-dwarfsstellar-flaresx-ray-sourcesradio-sourcesThe vicinities of intermediate-to-late type dwarf stars are considered as an adequate terrain to host planets suitable for life to form. However, they are oftentimes showing increased stellar activity, which should be taken into consideration when seeking potential habitable planetary systems. With the aim to reveal the effects of the magnetic field to the multi-band activity of dwarf stars, we search for associated radio emission for an extensive list of 14915 brown dwarfs and 15124 flaring stars. Methods. We utilised the first and second epoch catalogues and radio maps from all three epochs of the VLASS, supplemented with X-ray catalogues based on observations by the ROSAT, eROSITA, and XMM-Newton space telescopes, and 2-minute cadence optical light curves from the TESS mission. The radio-detected sub-sample was queried for concurrent TESS observations, and sources with coinciding light-curves were studied individually. We found no associated radio emission for brown dwarfs, and found 55 radio counterparts for the sample of flaring stars, out of which 7 have coincident TESS observations. The radio-detected sample follows both the radio-X-ray and the period-activity relations. We found a strong correlation between the radio powers and the stellar parameters of surface gravity, radius, and mass. We found no connection between the flare rate and the radio variability. For radio-detected stars with available effective temperatures and rotational periods, we estimated gyrochronological ages, which resulted in values of Tgyro<~1Gyr, with the majority of the sample being younger than 150Myr. We found no strong connection between the occurrence of optical flares and radio variability for the individually studied stars. We conclude that radio emission from intermediate-to-late type flaring stars is of synchrotron nature, and shares a common origin with X-ray processes. It is created by a predominantly young stellar population, and is the collective contribution of stellar flares, accretion, and coronal heating.2025A&A...699A.337Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/699/A337CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/699/A337https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/699/A337http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/699/A337https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/699/A337https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/699/A337http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/699/A337GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/699/A337/tablea1 (List of the 55 radio detected flaring stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/699/A337/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/699/A337/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/699/A337/tablea1?GETtext/xml+votable180.050000true90.6681683-0.86034030.0055555555555555566/462 1027 1050 1052 1054 1080 1159 1168-1169 3081 6113 7064 7078 7192 7561 7988 9866 9964 10401 11962 12009 12795 12957 14237 15241 16173 16206 16903 19016 19144 20983 21202 21501 22066 23517 23549 23743 24273 24281 24336 24481 26482 28699 28730 32516 39349 39893 39995 42493 42907 42952 48001https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/699/A337?format=asciiX-rayRadiodefaultJ/A+A/699/A337/tablea1List of the 55 radio detected flaring starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDTIC numbermeta.id;meta.mainlongn_ID[*] * for objects with coincident TESS observationsmeta.notecharrateFraction of time the star spends in flaring statetime.epochfloatrate34? Flares above the threshold 1e34 ergtime.epochfloatnullableTeff? Effective temperatureKphys.temperature.effectivefloatnullablee_Teff? Error of effective temperatureKstat.error;phys.temperature.effectivefloatnullableProt? Rotation perioddtime.periodfloatnullablee_Prot? Error of rotation perioddstat.errorfloatnullableTgyro? Gyrochronological ageMyrtime.agefloatnullableE_Tgyro? Upper limit on gyrochronological ageMyrstat.error;stat.maxdoublenullablee_Tgyro? Lower limit on gyrochronological ageMyrstat.errordoublenullableTypespectral typesrc.spTypecharsnr1SNR of epoch 1 VLASS imagestat.snrfloatrms1RMS of epoch 1 VLASS imagemJy/beamstat.stdev;obs.imagefloatS1Flux density of VLASS epoch 1mJyphot.flux.density;em.radio.1500-3000MHzfloatSimbadSimbad column added by the CDSmeta.ref.urlchare_S1Error of flux density of VLASS epoch 1mJystat.errorfloatsnr2SNR of epoch 2 VLASS imagestat.snrfloatrms2RMS of epoch 2 VLASS imagemJy/beamstat.stdev;obs.imagefloatS2Flux density of VLASS epoch 2mJyphot.flux.density;em.radio.1500-3000MHzfloate_S2Error of flux density of VLASS epochmJystat.errorfloatsnr3SNR of epoch 3 VLASS imagestat.snrfloatrms3RMS of epoch 3 VLASS imagemJy/beamstat.stdev;obs.imagefloatS3Flux density of VLASS epoch 3mJyphot.flux.density;em.radio.1500-3000MHzfloate_S3Error of flux density of VLASS epoch 3mJystat.errorfloatL1RX? 1st ROSAT survey luminosity 0.1-2.4keV1e-07Wphys.luminosity;em.X-ray.softfloatnullableL2RXpl? 2nd ROSAT survey luminosity 0.1-2.4keV1e-07Wphys.luminosity;em.X-ray.softfloatnullableLeRASS1? SRG/eROSITA luminosity 0.2-2.3keV1e-07Wphys.luminosity;em.X-ray.softfloatnullableLeRASSP3? SRG/eROSITA luminosity 1-2keV1e-07Wphys.luminosity;em.X-ray.softfloatnullableLXMM3? XMM-Newton luminosity 1-2keV1e-07Wphys.luminosity;em.X-ray.softfloatnullable_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main