J/A+A/328/175ivo://CDS.VizieR/J/A+A/328/175doi:10.26093/cds/vizier.33280175CDSAoki W.Tsuji T.2015-12-01T12:29:55Z1997-12-11T15:39:47ZCDS support team

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

cds-question@unistra.frgiant-starsinfrared-astronomyspectroscopyline-intensitiesThe analyses of high resolution infrared spectra have been done for CN lines in oxygen-rich cool evolved stars including 2 K giants, 20 M giants and 1 S-type star. Since CN lines analyzed in the present work are weak and resolved well, they are appropriate for quantitative analyses. CN lines of {DELTA}v=-2 and -1 sequences (red system) which are in the K- and the H-window regions, respectively, give the consistent nitrogen abundance for each star. The analyses of NH lines in the L-window region have been done for 5 late M giants for which CN lines have been also analyzed. Although the triplet structure of NH lines cannot be fully resolved, they are preferable because determination of nitrogen abundance is almost independent of other elemental abundances while nitrogen abundance based on CN depends on carbon abundance. The nitrogen abundances derived from NH for late M giants agree well with those from CN for which we adopt 7.75eV as the dissociation energy in the analysis. The results show that the nitrogen abundances in late M giants are larger than those in early M giants while decrease of the carbon abundance was found in late M giants by our previous work (Tsuji, 1991A&A...245..203T). These variations of abundances can not be explained by the first dredge-up model but require additional processing by the CN cycle and mixing after the first dredge-up. However, there is no obvious evidence of other processes such as the 3{alpha}-process and subsequent hot bottom burning in our program stars. Such variation of the carbon and nitrogen abundances is not well understood by the present evolutionary models of low-mass and intermediate-mass stars.1997A&A...328..175Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/328/175CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/328/175https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/328/175http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/328/175https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/328/175https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/328/175http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/328/175GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/A+A/328/175/tab10abCN lines in K- and H-windows region in K and early M giantsWindow[HK] Windowinstr.bandwidthcharLineLinemeta.id;spect.linecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharWNWavenumbercm**-1em.wavenumberdoublelog(gf)log of oscillation strengthphys.atmol.collStrengthfloatLEPLower excitation potentialcm**-1phys.atmol.excitation;stat.mindoublelog(EW)? Equivalent widthlog(0.1nm)spect.line.eqWidthfloatnullableJ/A+A/328/175/tab10cdCN lines in K- and H-windows region in late M giantsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namecharWindow[HK] WindowcharLineLinecharWNWavenumbercm**-1doublelog(gf)log of oscillation strengthfloatLEPLower excitation potentialcm**-1doublelog(EW)? Equivalent widthlog(0.1nm)floatnullableJ/A+A/328/175/tab10eNH lines in L-window region in late M type giantsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namecharLineLinecharWNWavenumbercm**-1doubleLEPLower excitation potentialcm**-1doublelog(gf)1log of oscillation strength (1)floatlog(gf)2log of oscillation strength (1)floatlog(gf)3log of oscillation strength (1)floatlog(EW)? Equivalent widthlog(0.1nm)floatnullable