J/MNRAS/495/1016ivo://CDS.VizieR/J/MNRAS/495/1016doi:10.26093/cds/vizier.74951016CDSRodriguez M.2024-08-21T20:14:23Z2023-09-04T09:53:45ZCDS support team

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

cds-question@unistra.frplanetary-nebulaemilky-way-galaxychemically-peculiar-starsvisible-astronomyspectroscopyI explore the effects of observational errors on nebular chemical abundances using a sample of 179 optical spectra of 42 planetary nebulae (PNe) observed by different authors. The spectra are analysed in a homogeneous way to derive physical conditions and ionic and total abundances. The effects of recombination on the [OII] and [NII] emission lines are estimated by including the effective recombination coefficients in the statistical equilibrium equations that are solved for O^+^ and N^+^. The results are shown to be significantly different than those derived using previous approaches. The O^+^ abundances derived with the blue and red lines of [OII] differ by up to a factor of 6, indicating that the relative intensities of lines widely separated in wavelength can be highly uncertain. In fact, the HeII lines in the range 4000-6800{AA} imply that most of the spectra are bluer than expected. Scores are assigned to the spectra using different criteria and the spectrum with the highest score for each PN is taken as the reference spectrum. The differences between the abundances derived with the reference spectrum and those derived with the other spectra available for each object are used to estimate the 1{sigma} observational uncertainties in the final abundances: 0.11dex for O/H and Ar/H, 0.14dex for N/H, Ne/H, and Cl/H, and 0.16dex for S/H.2020MNRAS.495.1016Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/495/1016CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/495/1016https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/495/1016http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/495/1016https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/495/1016https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/495/1016http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/495/1016GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/495/1016/tableb1 (Physical conditions of the PNe)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/495/1016/tableb1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/495/1016/tableb1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/495/1016/tableb1?GETtext/xml+votable180.050000true9.3167917-13.71627780.0055555555555555566/1552 2887 3819 6146 9233 9461 10378 11605 13676 13968 14118 14214 14796 14853 16871 21215 28726 28754 28779 28783 28819 28865 28906 29213 29254 29266 29451 29852 29886 30308 30472 30684 31775 32193 37661 38028 38075 40621 41646 42094 42446 48951https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/495/1016?format=asciiOpticaldefaultJ/MNRAS/495/1016/tableb1Physical conditions of the PNeSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNamePlanetary nebula namemeta.id;meta.maincharRefReferencemeta.ref;pos.framecharf_RefFlag on Ref (G1)meta.codecharne[SII]? Electron density derived from the [SII]{lambda}6716/{lambda}6731 diagnosiscm**-3phys.density;phys.electronintnullablene[OII]? Electron density derived from the [OII]{lambda}3726/{lambda}3729 diagnosiscm**-3phys.density;phys.electronintnullablene[ClIII]? Electron density derived from the [ClIII]{lambda}5518/{lambda}5538 diagnosiscm**-3phys.density;phys.electronintnullablene[ArIV]? Electron density derived from the [ArIV]{lambda}4711/{lambda}4740 diagnosiscm**-3phys.density;phys.electronintnullableneGeometric mean of the electron density (1)cm**-3phys.density;stat.meanintTe[NII]Electron temperature obtained from the diagnostics [NII]{lambda}5755/ ({lambda}6548+{lambda}6583)Kphys.temperature.electron;phys.electronintTe[OIII]Electron temperature obtained from the diagnostics [OIII]{lambda}4363/ ({lambda}4959+{lambda}5007)Kphys.temperature.electron;phys.electronintptotFinal score of the spectrum (see Section 6.9)meta.code.qualint_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.mainJ/MNRAS/495/1016/tableb2Ionic abundances derived from collisionally excited linesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNamePlanetary nebula namemeta.id;meta.maincharRefReferencemeta.ref;pos.framecharf_RefFlag on Ref (G1)meta.codecharO+(b)12+log(O^+^/H^+^) abundance calculated using the blue [OII] linesphys.abundfloatO+(r)? 12+log(O^+^/H^+^) abundance calculated using the red [OII] linesphys.abundfloatnullableO++12+log(O^++^/H^+^) abundancephys.abundfloatN+12+log(N^+^/H^+^) abundancephys.abundfloatNe++? 12+log(Ne^++^/H^+^) abundancephys.abundfloatnullableS+12+log(S^+^/H^+^) abundancephys.abundfloatS++? 12+log(S^++^/H^+^) abundancephys.abundfloatnullableAr++? 12+log(Ar^++^/H^+^) abundancephys.abundfloatnullableCl++? 12+log(Cl^++^/H^+^) abundancephys.abundfloatnullableptotFinal score of the spectrum (see Section 6.9)meta.code.qualintJ/MNRAS/495/1016/tableb3Ionic and total abundances of heliumHe+587612+log(He+/H) abundance derived from the {lambda}5876 linephys.abund.YfloatHe+6678? 12+log(He+/H) abundance derived from the {lambda}6678 linephys.abund.YfloatnullableHe+12+log(He+/H) abundancephys.abund.YfloatHe++? 12+log(He++/H) abundancephys.abund.YfloatnullableHe12+log(He/H) abundancephys.abund.YfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNamePlanetary nebula namemeta.id;meta.maincharRefReferencemeta.ref;pos.framecharf_RefFlag on Ref (G1)meta.codecharHe+4026? 12+log(He+/H) abundance derived from the {lambda}4026 linephys.abund.YfloatnullableHe+4388? 12+log(He+/H) abundance derived from the {lambda}4388 linephys.abund.YfloatnullableHe+4922? 12+log(He+/H) abundance derived from the {lambda}4922 linephys.abund.YfloatnullableHe+4471? 12+log(He+/H) abundance derived from the {lambda}4471 linephys.abund.YfloatnullableptotFinal score of the spectrum (see Section 6.9)meta.code.qualintJ/MNRAS/495/1016/tableb4Total abundancesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNamePlanetary nebula namemeta.id;meta.maincharRefReferencemeta.ref;pos.framecharf_RefFlag on Ref (G1)meta.codecharO(b)12+log(O/H) abundance calculated using the blue [OII] linesphys.abundfloatN(b)12+log(N/H) abundance calculated using the blue [OII] linesphys.abundfloatNe(b)? 12+log(Ne/H) abundance calculated using the blue [OII] linesphys.abundfloatnullableS(b)? 12+log(S/H) abundance calculated using the blue [OII] linesphys.abundfloatnullableAr(b)? 12+log(Ar/H) abundance calculated using the blue [OII] linesphys.abundfloatnullableCl(b)? 12+log(Cl/H) abundance calculated using the blue [OII] linesphys.abundfloatnullableO(r)? 12+log(O/H) abundance calculated using the red [OII] linesphys.abundfloatnullableN(r)? 12+log(N/H) abundance calculated using the red [OII] linesphys.abundfloatnullableNe(r)? 12+log(Ne/H) abundance calculated using the red [OII] linesphys.abundfloatnullableS(r)? 12+log(S/H) abundance calculated using the red [OII] linesphys.abundfloatnullableAr(r)? 12+log(Ar/H) abundance calculated using the red [OII] linesphys.abundfloatnullableCl(r)? 12+log(Cl/H) abundance calculated using the red [OII] linesphys.abundfloatnullableptotFinal score of the spectrum (see Section 6.9)meta.code.qualintJ/MNRAS/495/1016/tableb5Partial and final scores for the spectrap5[2/20] Score assigned to NHeI (1)meta.code.qualintptotFinal score of the spectrum (obtained from the addition of the previous scores)meta.code.qualintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNamePlanetary nebula namemeta.id;meta.maincharRefReferencemeta.ref;pos.framecharf_RefFlag on Ref (G1)meta.codecharp0[0/10] Score indicating whether the spectra was obtained with a CCD (p_0_=10) or not (p_0_=0)meta.code.qualintp1[20] Score related to the available temperature diagnosticsmeta.code.qualintNNumber of density diagnosticsmeta.numberintp2Score related to the density diagnosis (p_2_=9-15 for 1-4 working density diagnostics)meta.code.qualint[NII]? [NII] {lambda}6584/{lambda}6548 line ratiospect.line.intensity;arith.ratiofloatnullablep3[0/10] Score associated to [NII]meta.code.qualint[OIII]? [OIII] {lambda}5007/{lambda}4959 line ratiospect.line.intensity;arith.ratiofloatnullablep4[0/10] Score associated to [OIII]meta.code.qualintNHeINumber of HeI lines unaffected by optical depth effects available in the spectrameta.numberintNBLNumber of balmer lines (out of H{alpha}, H{gamma} and H{delta}) whose intensities are listed in the spectrameta.numberintP-B? Difference between the median deviations of the Paschen and Balmer lines from their expected values (see Section 6.7)stat.fit.paramfloatnullablep6[0/15] Score assigned using the behaviour of all these linesmeta.code.qualintJ/MNRAS/495/1016/refsReferences for tables B1-B5ComCommentsmeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReferencemeta.ref;pos.framecharBibCodeBibCodemeta.bib.bibcodecharAutAuthor's namemeta.bib.authorchar