J/A+AS/110/81ivo://CDS.VizieR/J/A+AS/110/81CDSvan der Walt D.J.Gaylard M.J.MacLeod G.C.2017-12-15T10:55:49Z1997-12-09T18:44:39ZCDS support team

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

cds-question@unistra.frinfrared-sourcesastrophysical-masersradio-astronomyWe present the results of our second search for 6.7-GHz methanol masers towards colour-selected IRAS sources. Five hundred and twenty IRAS sources that meet the far-infrared colour criteria set by Wood & Churchwell (1989ApJ...340..265W) for ultra-compact HII regions were searched for 6.7-GHz methanol maser emission, to a sensitivity limit of 5Jy. Thirty one new maser sources were detected. We also compare the FIR colours of the newly detected maser sources with those detected by Schutte et al. (1993MNRAS.261..783S) and the IRAS counterparts of sources that have both methanol and hydroxyl maser emission. It was found that the average flux distribution of the newly detected sources differs significantly from that of all other known 6.7-GHz methanol maser sources. It is argued that the differences may be due either to intrinsic differences between the three groups of sources or to interstellar extinction. An analysis of the relation between the 6.7-GHz maser and IRAS flux densities shows that the maser flux density is always less than the 100{mu}m flux density while only three sources have a maser flux density greater than the 60{mu}m flux density. Far-infrared pumping of the 6.7-GHz methanol masers is therefore in principle viable although it was found that the apparent maser efficiency will exceed 10 per cent for a significant number of sources in the case of FIR pumping by photons between 50 and 100{mu}m. The overall detection rates on the IRAS [25-12] vs [60-12] two-colour diagram are also presented. Possible new search strategies for masers in colour-selected IRAS sources are discussed.1995A&AS..110...81Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+AS/110/81CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+AS/110/81https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+AS/110/81http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+AS/110/81https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+AS/110/81https://vizier.iucaa.in/viz-bin/votable?-source=J/A+AS/110/81http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+AS/110/81GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+AS/110/81/table1 (Source IRAS names)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/110/81/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/110/81/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/110/81/table1?GETtext/xml+votable180.050000true74.22712237.9531840.005555555555555556Cone search capability for table J/A+AS/110/81/table2 (Parameters of detected 6.668-GHz A^+^-methanol masers)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/110/81/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/110/81/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/110/81/table2?GETtext/xml+votable180.050000true158.053338-58.0406390.0055555555555555565/3672 7203 7278 7578-7579 7605 9335 10420 10543 10624 6/1297 1307 1330 1385 1412 12970 12975 13050 14344 14352-14354 14356 14365 14389 14403 14409 14411 14430 14452-14453 14630 14640-14642 14664 14667 14670 14692-14693 14697 21519 21523 21542 21645 21688 22080 22122 23664 23766 23773 23795 23968-23969 23982 24320 24378 24487 24499 24554 28803 28808-28809 28817 28824 28826-28828 28830-28831 28875 28896-28897 28900-28901 28912-28913 28915 28917 28919 29090-29091 29095-29097 29100-29101 29103 29118-29119 29162 29504-29505 29508-29509 29511 29513 29515 29523 29528 29532 29535 30218-30219 30222 30240-30241 30243-30245 30256 30258 30260 30262-30263 30268-30269 30330 30341 30405 30417 30419 30592 30594 30604-30606 30616 30618 30622 30624 30641 30690-30692 30694-30695 30701 30714-30716 30718-30719 37207 37244 37333 37335 37364-37365 37367 37369 37372 37374 37747 37752 37839 37846 37848-37850 37894-37895 37897 37900-37902 37921-37924 37928 37934 38016 38019-38020 38024-38026 38032 39249-39250 39258 39273 39276 39375 39386 39396 39733 39926 40619 41597-41599 41652 41654-41655 41657-41658 41660-41661 41667 41673 41675-41678 41684-41686 41688 41696-41697 41706 41758-41759 41765 41767 41770 41773 41776 41778-41780 41782 41804 41806-41807 41811 41813-41815 41817 41820 41825 42159 42169-42171 42207 42210 42212 42214-42216 42224-42225 42228-42229 42378-42380 42382 42391-42393 42397-42398 42435 42437-42439 42441 42445 42450 42454 42456-42458 42460-42462 42500 42502 42515-42516 43019 43021 43024 43027 430404.439466485724119e-24 4.439466485724119e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+AS/110/81?format=asciiInfraredRadiodefaultJ/A+AS/110/81/table1Source IRAS namesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNote[abcd] Characteristics (1)meta.notecharIRASIRAS name (2)meta.id;meta.maincharprimaryMSimbad column added by the CDSmeta.ref.urlcharPSCDetails from the IRAS-Point Source Catalog (II/125)meta.ref.urlchar_RAPosition from IRAS-PSC catalog (II/125) (right ascension part)degpos.eq.ra;meta.main_DEPosition from IRAS-PSC catalog (II/125) (declination part)degpos.eq.dec;meta.mainJ/A+AS/110/81/table2Parameters of detected 6.668-GHz A^+^-methanol masersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIRASIRAS name (Cat. <II/125>)meta.id;meta.maincharRA1950Right ascension (1950)pos.eq.ra;meta.mainDE1950Declination (1950)pos.eq.dec;meta.mainGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latfloatVminVelocity range (lower value)km/sphys.veloc;instr.bandwidthintVmaxVelocity range (upper value)km/sphys.veloc;instr.bandwidthintSpeakPeak flux density of 6.7GHz methanol lineJyphot.fluxfloate_Speakrms uncertainty on SpeakJystat.errorfloatIpeakIntegrated peak flux density of methanol lineJy.km/sphot.flux.density;stat.maxfloate_Ipeakrms uncertainty on IpeakJy.km/sstat.errorfloatPSCDetails from the IRAS-Point Source Catalog (II/125)meta.ref.urlchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexed