J/MNRAS/461/839ivo://CDS.VizieR/J/MNRAS/461/839doi:10.26093/cds/vizier.74610839CDSKashuba S.V.Andrievsky S.M.Chekhonadskikh F.A.Luck R.E.,Kovtyukh V.V.Korotin S.A.Krelowski J.Galazutdinov G.A.2024-08-16T20:18:05Z2017-12-19T16:05:55ZCDS support team

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

cds-question@unistra.frvariable-starsline-intensitiesstellar-distanceWe have investigated the diffuse interstellar band (DIB) at 661.3nm seen in the spectra of Cepheid stars. After removal of the blending lines of ionized yttrium and neutral iron, we determined the equivalent widths (EWs) of the DIB and used these values to investigate the E(B-V)-DIB EW relation. The relation found from Cepheids matches that found in B stars. This relation can help to find the reddening for newly discovered Cepheids without extensive photometric data, and thus determine their distances. The relation between E(B - V) and the DIB EW does not yield precise reddening values. It is not a substitute for better photometric or spectroscopic methods. At best, it is indicative, but it provides some information that may not be otherwise available. Defining R*=E(B-V)/DIB EW, which we consider to be the analogue of R=E(B-V)/A_V_, we investigated the Galactic longitudinal dependence of R* assuming that the DIB EW value is representative of the interstellar absorption A$_v$. We found that there is an apparent increase of the R* value that corresponds to the abnormal absorption seen towards Cygnus constellation. Finally, we constructed a 2D map of the DIB EW distribution in the Galactic disc basing on our rather limited sample of 253 spectra of 176 Cepheids.2016MNRAS.461..839Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/461/839CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/461/839https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/461/839http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/461/839https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/461/839https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/461/839http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/461/839GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/461/839/table1 (List of the 185 observed stars, their parameters and DIB EWs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/461/839/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/461/839/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/461/839/table1?GETtext/xml+votable180.050000true91.645614426.32922140.0055555555555555566/1239 1331 1340 1348 1388 1402 1411 1426 1429 1431-1432 1441 1445 1467 1625 1765 1829 1836 1858 1920 1985 3022 3033 3050 3052 3054 3059-3060 3063 3131 3157 3252 3255 3261 3263 3284-3285 3304 3306 3322 3328 3342 3361-3362 3365 3459 3599-3601 3627 3629 3645 3656 3712-3713 3722 3731 12846 12963 12968 12970-12971 13933 14047 14075 14212 14238-14239 14246 14251 14260 14262 14291-14292 14295 14301 14317 14320-14321 14407 14409 14411 14427 14430 14445 14449 14453 14455 14457 14469 14602 14625 14629-14630 14634 14640 14653 14690 14698 14736 15378 15392-15393 15461 15585 15632 15698 21671 21679 21683 21686 22020 22044 22064 22068-22069 22071 22074 22106 22115-22116 22122 22124 22169 22207 22214 22219 22221 22223 22227 22255 22267 22438 23622 23635 23669-23670 23762 23778 23841 23846 23852 23922 24002 24326 24340 24372 24424 24450 24453 24478-24479 24527 29533 29852 29897 29999 30211 30222-30223 30235 30245 30258 30265 30270 30307 30311 30321 30333 30504 30596 30641 30646 32012 32064https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/461/839?format=asciidefaultJ/MNRAS/461/839/table1List of the 185 observed stars, their parameters and DIB EWsDist? Distancepcpos.distance;pos.heliocentricintnullablePhase? Phasetime.phasefloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharNspSpectrum number when more than one for the starmeta.idcharDateObservation datetime.epoch;obsnullableTeffEffective temperatureKphys.temperature.effectiveintloggSurface gravitylog(m.s**-2)phys.gravityfloatvtMicroturbulent velocitykm/sphys.velocfloatGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latfloatE(B-V)? B-V colour excessmagphot.color.excessfloatnullableEW(Y+Fe)Y+Fe equivalent widthnmspect.line.eqWidthdoubleEW(DIB)DIB 661.356nm equivalent widthnmspect.line.eqWidth;em.opt.RdoubleSimbadSimbad column added by the CDSmeta.ref.urlchar_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