J/A+A/704/A103ivo://CDS.VizieR/J/A+A/704/A103CDSSitnova T.M.Mashonkina L.I.Romanovskaya A.M.Giribaldi R.E.Choplin A.2026-03-02T06:25:50Z2025-12-08T08:20:45ZCDS support team

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

cds-question@unistra.frmilky-way-galaxychemically-peculiar-starschemical-abundancesline-intensitiesvisible-astronomyWe present a spectroscopic analysis of ten carbon enhanced metal-poor (CEMP) stars of type CEMP-s and CEMP-rs and determine their non-local thermodynamic equilibrium (NLTE) abundances of Ba and Eu, as well as the fractions of the odd Ba isotopes (F_odd_). Determination of F_odd_ in stars provides unambiguous information about the s-process contribution to their total Ba abundance. We aim to obtain observational constraints on the enrichment scenarios of CEMP-rs stars. The Ba abundances inferred from the resonance BaII 4554 and 4934{AA} lines depend on the adopted Ba isotope mixture. We perform calculations for different F_odd_ from 0.1 to 1.0 and determine the corresponding abundances from the BaII resonance lines in each sample star. In addition, we determine the Ba abundances from the BaII subordinate lines, which are almost independent of F_odd. We then compare the Ba abundances derived from the subordinate lines with those from the BaII resonance lines. We found different F_odd values in CEMP-s and CEMP-rs stars. CEMP-s stars exhibit F_odd_=0.05_-0.03_^+0.07^, 0.17_-0.14_^+0.63^, 0.19_-0.14_^+0.50^, and 0.19_-0.12_^+0.33^. The obtained values agree, within the error bars, with the s-process F_odd_=0.10 and the solar F_odd_=0.18. Although the uncertainties are large, in three of four stars, the possibility of Ba isotopes origin in a pure r-process with F_odd_=0.75 can be excluded. CEMP-rs stars show F_odd_=0.34_-0.21_^+0.55^, 0.36_-0.14_^+0.23^, 0.44_-0.22_^+0.43^, 0.53_-0.38_^+0.47^, and 0.57_-0.31_^+0.43^, which are higher compared to those in CEMP-s stars. Although the uncertainties are large, in four of five stars, the possibility of a pure s-process origin for the Ba isotopes can be excluded. The obtained values agree, within the error bars, with the predicted i-process F_odd_=0.6 to 0.8. Our analysis of CEMP-rs stars with [Ba/Eu]>0 argues that their [Ba/Eu] and F_odd_ cannot be jointly explained by a mixture of material produced by the r- and s-processes. The obtained results argue that the i-process is responsible for the chemical composition of these CEMP-rs stars.2025A&A...704A.103Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/704/A103CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/704/A103https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/704/A103http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/704/A103https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/704/A103https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/704/A103http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/704/A103GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/704/A103/stars (star)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/704/A103/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/704/A103/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/704/A103/stars?GETtext/xml+votable180.050000true175.8476558028620.3494788581199980.0055555555555555566/10165 16880 25595 26829 27322 28223 28251 34008 46704 49078https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/704/A103?format=asciiOpticaldefaultJ/A+A/704/A103/starsstarrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainNameStar namemeta.id;meta.maincharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/A+A/704/A103/table2NLTE and LTE abundances and EWs (m{AA}) of BaII lines in the starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharParamParameter name (NLTE, LTE, EW) (G1)meta.id;stat.paramcharValue2? BaII 4554{AA}, for F_odd_=1.00 value for Paramstat.fit.paramfloatnullableValue3? BaII 4554{AA}, for F_odd_=0.75 value for Paramstat.fit.paramfloatnullableValue4? BaII 4554{AA}, for F_odd_=0.62 value for Paramstat.fit.paramfloatnullableValue5? BaII 4554{AA}, for F_odd_=0.43 value for Paramstat.fit.paramfloatnullableValue6? BaII 4554{AA}, for F_odd_=0.18 value for Paramstat.fit.paramfloatnullableValue7? BaII 4554{AA}, for F_odd_=0.10 value for Paramstat.fit.paramfloatnullableValue8BaII 4934{AA}, for F_odd_=1.00 value for Paramstat.fit.paramfloatValue9BaII 4934{AA}, for F_odd_=0.75 value for Paramstat.fit.paramfloatValue10BaII 4934{AA}, for F_odd_=0.62 value for Paramstat.fit.paramfloatValue11BaII 4934{AA}, for F_odd_=0.43 value for Paramstat.fit.paramfloatValue12BaII 4934{AA}, for F_odd_=0.18 value for Paramstat.fit.paramfloatValue13BaII 4934{AA}, for F_odd_=0.10 value for Paramstat.fit.paramfloatValue14? BaII 5853{AA} value for Paramstat.fit.paramfloatnullableValue15BaII 6141{AA} value for Paramstat.fit.paramfloatValue16BaII 6496{AA} value for Paramstat.fit.paramfloatx_Value2Unit of Value2-Value16 parametersmeta.unitcharJ/A+A/704/A103/table3NLTE and LTE abundances and EWs (m{AA}) of EuII lines in the starsNameStar namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintParamParameter name (NLTE, LTE, EW) (G1)meta.id;stat.paramcharValue2? EuII 3819{AA} value for Paramstat.fit.paramfloatnullablel_Value3Limit flag on Value3meta.code.errorcharValue3? EuII 4129{AA} value for Paramstat.fit.paramfloatnullableValue4? EuII 4205{AA} value for Paramstat.fit.paramfloatnullablex_Value2Unit of Value2-Value4 parametersmeta.unitchar