J/A+A/660/A70ivo://CDS.VizieR/J/A+A/660/A70doi:10.26093/cds/vizier.36600070CDSMathys G.Kurtz D.W.Holdsworth D.L.2023-07-03T14:13:20Z2022-09-28T13:11:17ZCDS support team

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

cds-question@unistra.frvariable-starspeculiar-variable-starsmagnetic-fieldsThe rotation periods of the magnetic Ap stars span five to six orders of magnitude. While it is well established that period differentiation must have taken place at the pre-main sequence stage, the physical processes that lead to it remain elusive. The existence of Ap stars that have rotation periods of tens to hundreds of years is particularly intriguing, and their study represents a promising avenue to gain additional insight into the origin and evolution of rotation in Ap stars. Historically, almost all the longest period Ap stars known have been found to be strongly magnetic; very few weakly magnetic Ap stars with very long periods have been identified and studied. To remedy that, we showed how a systematic search based on the analysis of TESS photometric data could be performed to identify super-slowly rotating Ap (ssrAp) stars independently of the strengths of their magnetic fields, with the intention to characterise the distribution of the longest Ap star rotation periods in an unbiased manner. We successfully applied this method to the analysis of the TESS 2-min cadence observations of Ap stars of the southern ecliptic hemisphere. For our present study, we applied the same approach to the analysis of the TESS 2-min cadence observations of Ap stars of the northern ecliptic hemisphere. We confirm that the technique leads to the reliable identification of ssrAp star candidates in an unbiased manner. We find 67 Ap stars with no rotational variability in the northern ecliptic hemisphere TESS data. Among them, 46 are newly identified ssrAp star candidates, which is double the number found in the southern ecliptic hemisphere. We confirm that super-slow rotation tends to occur less frequently in weakly magnetic Ap stars than in strongly magnetic stars. We present new evidence of the existence of a gap between ~2 kG and ~3 kG in the distribution of the magnetic field strengths of long period Ap stars. We also confirm that the incidence of roAp stars is higher than average in slowly rotating Ap stars. We report the unexpected discovery of nine definite and five candidate {delta} Sct stars, and of two eclipsing binaries. This work paves the way for a systematic, unbiased study of the longest period Ap stars, with a view to characterise the correlations between their rotational, magnetic, and pulsational properties.2022A&A...660A..70Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/660/A70CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/660/A70https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/660/A70http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/660/A70https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/660/A70https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/660/A70http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/660/A70GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/660/A70/tablea1 (*List of long-period Ap stars found by our technique in the TESS Sectors 14-26 data)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/660/A70/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/660/A70/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/660/A70/tablea1?GETtext/xml+votable180.050000true80.409181432.75877310.0055555555555555566/510 915 1285 1382 1448 2229 2411 2490 2513 2818 2903 2987 3266 3361 3705 3754 6070 8037 8157 9133 9144 10151 10791 12978 13183 13186 13206 13229 13303 13690 13872 13952 14035 14202 14242 14252 14284 14301 14304 14491 14502-14503 14534 14743 14960 14964 15126 15326 15386 20340 20457 24467 24469 24489 24499 24505 24507 24512 24523 24544 24546 28192 282173.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/660/A70?format=asciidefaultJ/A+A/660/A70/tablea1*List of long-period Ap stars found by our technique in the TESS Sectors 14-26 dataTICTIC numbermeta.id;meta.mainlongrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintONameOther namemeta.idcharSpTypeSpectral typesrc.spTypecharn_SpType[d] Note on SpType (1)meta.notecharVmagV magnitudemagphot.mag;em.opt.Vfloatn_Vmag[b] b for V magnitude from Zacharias et al. (2004, Cat. I/297)meta.notecharTeff? Effective temperatureKphys.temperature.effectiveintnullablelogg? Surface gravitylog(cm.s**-2)phys.gravityfloatnullableroAproAp flagsrc.classchar<Bz>rms? Root-mean-square longitudinal fieldkGstat.stdev;instr.det.noisefloatnullableB0? Average value over a rotation cycle of the mean magnetic field modulus <B>kGphys.magField;stat.meanfloatnullableQ0? Average value over a rotation cycle of the mean quadratic magnetic field <Bq>kGphys.magField;stat.meanfloatnullabler_B0References for magnetic field (3)meta.refcharProt? Rotational perioddtime.perioddoublenullablen_Prot[ce] Note on Prot (1)meta.notecharu_Prot[?] Uncertainty flag on Protmeta.code.errorcharSimbadSimbad column added by the CDSmeta.ref.urlcharr_Prot? References for rotational period (3)meta.ref;pos.frameintnullableLinesLines (2)meta.id;spect.linecharl_vsiniLimit flag on vsinimeta.code.error;phys.veloc.rotatcharvsini? Rotational velocitykm/sphys.veloc.rotatfloatnullabler_vsiniReferences for rotational velocity (3)meta.refcharNotesNotesmeta.notecharSectorsTESS sectorsmeta.codechar_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