J/A+A/584/A93ivo://CDS.VizieR/J/A+A/584/A93doi:10.26093/cds/vizier.35840093CDSJuvela M.Ristorcelli I.Marshall D.Montillaud J.Pelkonen V.-M.,Ysard N.McGehee P.Paladini R.Pagani L.Malinen J.,Rivera-Ingraham A.Lefevre C.Toth L.V.Montier L.A.Bernard J.-P.,Martin P.2015-11-26T12:25:38Z2015-11-26T13:22:00ZCDS support team

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

cds-question@unistra.frmilky-way-galaxyextinctionThe project Galactic Cold Cores has carried out Herschel photometric observations of interstellar clouds where Planck satellite survey has located cold and compact clumps. The sources represent different stages of cloud evolution from starless clumps to protostellar cores and are located in different Galactic environments. We examine this sample of 116 Herschel fields to estimate the submillimetre dust opacity and to look for variations that could be attributed to the evolutionary stage of the sources or to environmental factors, including the location within the Galaxy. The submillimetre dust opacity is derived from Herschel data and near-infrared observations of the reddening of background stars are converted to near-infrared optical depth. We investigate the systematic errors affecting these parameters and use modelling to make corrections for the expected biases. The ratio of 250{mu}m and J band opacities is correlated with the Galactic location and the star formation activity. Local variations in the ratio {tau}(250{mu}m)/{tau}(J) are searched using the correlation plots and maps of the opacity ratio. We find a median ratio of {tau}(250{mu}m)/{mu}(J)=(1.6+/-0.2)*10^-3^, which is more than three times the mean value reported for the diffuse medium. Assuming an opacity spectral index {beta}=1.8 instead of {beta}=2.0, the value would be smaller by ~30%. No significant systematic variation is detected with Galactocentric distance or with Galactic height. Examination of the {tau}(250{mu}m)/{tau}(J) maps reveals half a dozen fields with clear indications of local increase of submillimetre opacity, up to {tau}(250{mu}m)/{tau}(J)~4*10^-3^, towards the densest clumps. These are all nearby fields with spatially resolved clumps of high column density. We interpret the increase in the far-infrared opacity as a sign of grain growth in the densest and coldest regions of interstellar clouds.2015A&A...584A..93Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/584/A93CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVI/139 : Herschel Observation Log (Herschel Science Centre, 2013)J/A+A/584/A92 : Galactic cold cores. IV. Cold submm sources (Montillaud+, 2015)J/A+A/584/A94 : Galactic cold cores. VI. Herschel fields list (Juvela+, 2015)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/584/A93https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/584/A93http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/584/A93https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/584/A93https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/584/A93http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/584/A93GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/584/A93/table1 (List of Herschel fields)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/584/A93/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/584/A93/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/584/A93/table1?GETtext/xml+votable180.050000true250.23625-18.5833060.005555555555555556Cone search capability for table J/A+A/584/A93/tablee1 (Herschel observation IDs and reference regions of extinction calculations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/584/A93/tablee1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/584/A93/tablee1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/584/A93/tablee1?GETtext/xml+votable180.050000true250.997917-18.4890.0055555555555555565/3648 6/101 103 255 597 1111 1117 1217 1220 1229 1234 1247 1255 1262 1266 1418 1529 1531 1551 1563 1581 1592 1601 1636 1639 1800 1802 1935 1940 1946 1959 1964-1966 2931 2937 3006 3223 3228 3645 3688 3850 3873 3875 3884 4059 4062 7973 7981 13026 13033 13112-13113 13310 13785-13786 13925 13927 13981 13991 13997 14024 14207 14276 14278-14279 14678 15421 15423 15540 15542 15552 15554 15564 15576 15578 15585 15673 15676 15683 15688 15781 15783 15825 15833 16151 16154 16192 17594 17936 18411 20025 20028 20248-20249 20862-20863 21336-21337 21339 21397 21440 21454 22031 22042 22064 22067 22081 22084 22555 22577 22817 22819 23572-23573 23576-23577 23614 23625 23630 23697 23763 23766 23810-23811 24079 24090 24092-24093 24200 24202 24489 24493 24509 24552 29212-29213 29238 29242 29245 29328 29356-29357 29440 29442 29566 29638 29654 29673 29675 29685 30338 30344 30376 30427 30431 30449 30452-30453 30747-30749 30769 30802-30803 31241-31242 31256-31257 31263 31328 37126 37855 38408-38409 38447 38456 38538 38567 38578 39188-39189 39231 39316 39326 39348 39390-39391 39551 39720 41052-41053 41514-41515 41638 41644 41851 41879 41922 41937 42108 42110 42295 42298 42301 42385 42547 42556 42560 42562 42760 42762 42764-42765 43143 43148https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/584/A93?format=asciiOpticaldefaultJ/A+A/584/A93/table1List of Herschel fieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the fieldmeta.id;obs.fieldcharRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainAreaField sizearcmin**2phys.angSizeintDist? Estimated distancepcpos.distancefloatnullableE_Dist? Error on Distance (upper value)pcstat.error;stat.maxfloatnullablee_Dist? Error on Distance (lower value)pcstat.errorfloatnullableRARReference Right Ascension (J2000.0) (1)meta.ref;pos.eq.raDERReference Declination (J2000.0)meta.ref;pos.eq.decRadiusRadius of reference regionarcminphys.angSize;obs.fieldfloatNames? Other names (2)meta.id;meta.maincharJ/A+A/584/A93/tablee1Herschel observation IDs and reference regions of extinction calculationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of Herschel fieldmeta.id;obs.fieldcharRAJ2000Reference Right Ascension (J2000.0) (1)pos.eq.ra;meta.mainDEJ2000Reference Declination(J2000.0)pos.eq.dec;meta.mainRadiusRadius of reference regionarcminphys.angSize;obs.fieldfloatID1Herschel Observation ID (2)meta.idID2? Second Herschel Observation IDmeta.idnullableID3? Third Herschel Observation IDmeta.idnullableID4? Fourth Herschel Observation IDmeta.idnullableID5? Fifth Herschel Observation IDmeta.idnullableID6? Sixth Herschel Observation IDmeta.idnullable