J/MNRAS/483/2282ivo://CDS.VizieR/J/MNRAS/483/2282doi:10.26093/cds/vizier.74832282CDSReed M.D.Telting J.H.Ketzer L.Crooke J.A.Baran A.S.Vos J.,Nemeth P.Ostensen R.H.Jeffery C.S.2024-08-19T20:15:43Z2022-08-11T09:06:34ZCDS support team

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

cds-question@unistra.frasteroseismologysubdwarf-starsb-starsmultiple-starsThis paper presents spectroscopic and seismic analyses of two rare hybrid pulsating subdwarf B (sdB) stars, PG 0048+091 and PG 1315-123, which are dominated by pressure (p)-mode pulsations. These are only the second and third sdB pulsators with detected frequency multiplets in both the p- and g (gravity)-mode regions. This allows an examination of the radial rotation profiles and p- and g-mode overtone spacings. Frequency multiplets indicate that PG 1315-123 rotates uniformly, as a solid body, while PG 0048+091 is rotating faster in the outer envelope. g- and p-mode overtone spacings for PG 1315-123 agree with previous findings and model predictions at 237 and ~1000s while those for PG 0048+091 are significantly shorter at 207 and <250s, respectively. The cause of PG 0048+091's discrepancies is likely related to core structural differences which could be related to progenitor mass. Spectroscopic findings show that both stars lie on the hot end of the instability region and are most likely in long-period binaries with main-sequence companions. Their high temperatures challenge driving theory, which produces g-mode pulsations only at cooler temperatures. Another challenge is the appearance of pulsations with both driven and stochastic properties. Such a variety of pulsation properties makes these stars very interesting and important for understanding hot horizontal-branch stars.2019MNRAS.483.2282Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/483/2282CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/483/2282https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/483/2282http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/483/2282https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/483/2282https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/483/2282http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/483/2282GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/MNRAS/483/2282/table4p-mode frequencies detected for PG 0048+091recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDp-mode frequency identifiermeta.id;meta.maincharFreqp-mode frequencies detected for PG 0048+091uHzem.freqdoublee_Freq? Error on FrequHzstat.errorfloatnullableStocIn this column, 'stochastic' indicates there is a broad excess of powermeta.codecharAmp? Amplitude (in ppt)src.var.amplitudefloatnullableS/N? Signal to noise ratiostat.snrfloatnullablemodeMode of degree and azimuthal order (l,m)stat.fit.paramcharf2004/5Closest frequency from Reed et al. (2007ApJ...664..518R)em.freqcharJ/MNRAS/483/2282/table5g-mode frequencies detected for PG 0048+091recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDg-mode frequency identifiermeta.id;meta.maincharFreqg-mode frequencies detected for PG 0048+091uHzem.freqfloate_FreqError on FrequHzstat.errorfloatPeriodPeriodstime.periodfloate_PeriodError on Periodsstat.error;time.periodfloatAmpAmplitude (in ppt)src.var.amplitudefloatS/NSignal to noise ratiostat.snrfloatmodeMode of degree and azimuthal order (l,m)stat.fit.paramcharn? Relative radial indicesstat.fit.paramintnullableDev? Deviation from the asymptotic sequencestat.fit.paramfloatnullableJ/MNRAS/483/2282/table6Lorentzian widths and power (Hi) fitted to observations for PG 0048+091recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFreqFrequencies associated to wide regions of excess pulsation poweruHzem.freqintLW1Lorentzian width form the power spectra fituHzsrc.var.amplitudefloatLW2? Second Lorentzian width form the power spectra fituHzsrc.var.amplitudefloatnullableHi1Power form the power spectra fit (in ppt^2^)stat.fit.paramfloatHi2? Second Power form the power spectra fit (in ppt^2^)stat.fit.paramfloatnullableJ/MNRAS/483/2282/table7p-mode frequencies detected for PG 1315-123recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDp-mode frequency identifiermeta.id;meta.maincharFreqp-mode frequencies detected for PG 1315-123uHzem.freqfloate_Freq? Error on FrequHzstat.errorfloatnullableStocIn this column, 'stochastic' indicates there is a broad excess of powermeta.codecharAmp? Amplitude (in ppt)src.var.amplitudefloatnullableS/N? Signal to noise ratiostat.snrfloatnullablemode? Mode of degree and azimuthal order (l,m)stat.fit.paramintnullableJ/MNRAS/483/2282/table8g-mode frequencies detected for PG 1315-123Dev? Deviation from the l=1 asymptotic sequencestat.fit.paramfloatnullableFreqg-mode frequencies detected for PG 1315-123uHzem.freqfloate_FreqError on FrequHzstat.errorfloatPeriodPeriodstime.periodfloate_PeriodError on Periodsstat.error;time.periodfloatAmpAmplitude (in ppt)src.var.amplitudefloatS/NSignal to noise ratiostat.snrfloatm? Azimuthal order, if a multiplet (1)stat.fit.paramintnullablen? Relative radial indexmeta.code;spect.dopplerVelocintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDg-mode frequency identifiermeta.id;meta.maincharJ/MNRAS/483/2282/table9Lorentzian widths fitted to observations of PG 1315-123recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFreqFrequencies associated to wide regions of excess pulsation poweruHzem.freqintLWLorentzian width form the power spectra fituHzsrc.var.amplitudefloatHiPower form the power spectra fit (in ppt^2^)stat.fit.paramfloat