J/ApJS/245/12ivo://CDS.VizieR/J/ApJS/245/12doi:10.26093/cds/vizier.22450012CDSOuyang X.-J.Chen XiShen Z.-Q.Yang K.Li X.-Q.Chen H.-Y.Zhao Z.,Sobolev A.M.2020-09-15T09:16:51Z2020-04-29T12:20:03ZCDS support team

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

cds-question@unistra.frh-ii-regionsastrophysical-masersradio-astronomyinterstellar-mediumWe report a systematic survey of a 6.7GHz Class II methanol maser toward a sample of 448 sources selected from the Red Midcourse Space Experiment Source catalog. These sample sources are composed of high-mass star-forming region (HMSFR) candidates and have been studied as tracers of HMSFRs, such as water masers or radio continuum emission of ultracompact HII region. The survey was conducted using the Shanghai Tianma Radio Telescope. Through the observations, we simultaneously studied the 4.7 and 6.0GHz excited-state interstellar hydroxyl (OH) maser lines and 10 hydrogen radio recombination lines (RRLs) in the C band. In total, we detected 6.7GHz methanol masers and RRLs from 102 and 116 sources, respectively. In addition, 4, 3, and 10 sources exhibit OH masers at 4765.56, 6030.75, and 6035.09MHz transitions, respectively. Through the survey, we identified four new 6.7GHz methanol maser sources and three new excited-state OH maser sources (one at 4750MHz and two at 6035MHz). The statistical analysis demonstrated that there is a positive correlation of luminosity between 6.7GHz methanol masers and RRLs. A good correlation of integrated luminosity between radio continuum emission and the 6.7GHz methanol masers is presented with respect to the RRL emission sources. The average of the integrated luminosities of the RRLs in the sources with 6.7GHz masers is greater than those without the 6.7GHz masers; similarly, the average of integrated luminosities of the 6.7GHz methanol masers in the sources with RRLs is greater than those without the RRLs. Moreover, we found that the averages of the emission measure and electron temperature of HII regions associated with 6.7GHz methanol masers are larger than those without the 6.7GHz methanol masers. This suggests that the masers are most likely produced in high gas density and luminous regions with brighter RRLs and higher radio continuum emission.2019ApJS..245...12Ohttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/245/12CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/114 : MSX6C Infrared Point Source Catalog (Egan+, 2003)VIII/96 : 6-GHz methanol multibeam maser catalogue (Caswell+, 2010-12)J/A+A/171/261 : RRLs of Southern HII Regions (Caswell+ 1987)J/MNRAS/291/261 : Methanol maser of IRAS-selected sources (Walsh+ 1997)J/A+AS/137/43 : OH/H2O masers database (Forster+, 1999)J/A+AS/143/269 : 6.7GHz methanol maser emission survey (Szymczak+, 2000)J/A+A/403/1095 : 6.7GHz methanol maser survey of low-mass YSO (Minier+, 2003)J/A+A/417/615 : Maser and outflows in UC HII region (Codella+, 2004)J/ApJS/155/149 : CH_3_OH 7_0_-6_1_ A^+^ maser sources (Kurtz+, 2004)J/MNRAS/359/1498 : Class I and class II methanol masers (Ellingsen+, 2005)J/AJ/129/348 : Radio compact HII regions in the Milky Way (Giveon+, 2005)J/A+A/432/737 : General Cat. of 6.7GHz Methanol Masers (Pestalozzi+, 2005)J/A+A/434/613 : Water maser survey of methanol masers (Szymczak+, 2005)J/MNRAS/377/571 : GLIMPSE 6.7GHz methanol masers non-det. (Ellingsen+, 2007)J/A+A/487/253 : The RMS survey: ^13^CO observations of YSOs (Urquhart+, 2008)J/ApJ/702/1615 : CH_3_OH maser survey of EGOs (Cyganowski+, 2009)J/A+A/501/539 : RMS survey. 6cm observations of YSOs (Urquhart+, 2009)J/ApJS/194/32 : HII Region Discovery Survey (HRDS). II. (Anderson+, 2011)J/ApJS/196/9 : 95GHz methanol maser survey of GLIMPSE EGOs (Chen+, 2011)J/MNRAS/418/1689 : Red MSX water maser and ammonia emissions (Urquhart+, 2011)J/MNRAS/416/1764 : H_2_O Southern Galactic Plane Survey (HOPS) (Walsh+, 2011)J/ApJS/200/5 : 95GHz class I methanol maser survey (Chen+, 2012)J/AN/333/634 : Torun methanol source catalogue (Szymczak+, 2012)J/ApJS/206/9 : New EGOs from Spitzer GLIMPSE II survey. I. (Chen+, 2013)J/ApJ/763/2 : 95GHz methanol masers in molecular outflows (Gan+, 2013)J/ApJS/208/11 : Red MSX Source Survey: massive protostars (Lumsden+, 2013)J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)J/MNRAS/439/2584 : Southern methanol masers at 36 and 44GHz (Voronkov+, 2014)J/MNRAS/442/2240 : Accurate water maser positions from HOPS (Walsh+, 2014)J/ApJ/833/18 : Ultra-compact HII regions & methanol masers. I. (Hu+, 2016)J/ApJS/227/26 : ATCA obs. of ground-state OH masers (Qiao+, 2016)J/ApJ/846/160 : 6.7GHz Class II methanol maser survey (Yang+, 2017)J/ApJS/231/20 : A new 95GHz methanol maser catalog. I. (Yang+, 2017)J/ApJS/234/33 : A GBT survey of large Galactic HII regions (Anderson+, 2018)J/ApJS/241/18 : A 6.7GHz methanol maser survey. II. |b|<2{deg} (Yang+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/245/12https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/245/12http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/245/12https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/245/12https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/245/12http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/245/12GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/245/12/table1 (Ultracompact HII region with radio continuum emission)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/245/12/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/245/12/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/245/12/table1?GETtext/xml+votable180.050000true272.1580833-19.89969440.005555555555555556Cone search capability for table J/ApJS/245/12/table2 (Water maser or ammonia emission sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/245/12/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/245/12/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/245/12/table2?GETtext/xml+votable180.050000true270.0945-18.86888890.0055555555555555565/3660 7275 7278 7376 7377 7383 7564 7605 7679 6/1329 1412 1781 1848 1925 1927 1928 1930 1963 3023 3031 3039 3071 3175 3184 3195 3198 3268 3271 3302 3309 3311 3320 3338 3606 3628 3630 3649 3727 3728 3729 3730 3738 12970 12971 12975 13050 14014 14267 14278 14282 14304 14307 14308 14309 14311 14312 14314 14317 14321 14353 14354 14356 14358 14365 14411 14430 14452 14603 14606 14616 14621 14622 14624 14625 14647 14654 14666 14667 14670 14671 14682 14683 14685 14688 14689 14691 14692 14693 14696 14704 14706 14711 14713 14716 15368 15370 15374 15385 15408 15409 15414 15434 15435 15448 15449 15452 15455 15456 15473 15476 15477 15624 15626 15627 15642 15682 20831 21542 21639 21643 21645 21671 21689 22045 23666 23969 24325 24476 24493 24496 24515 24554 29091 29092 29094 29095 29097 29116 29118 29440 29461 29463 29513 29517 29522 29529 30216 30218 30219 30222 30240 30241 30243 30244 30245 30262 30263 30266 30267 30268 30269 30313 30314 30315 30318 30319 30328 30330 30341 30348 30359 30401 30405 30416 30417 30419 30592 30594 30595 30600 30604 30605 30616 30618 30619 30621 30624 30625 30640 30644 30690 30691 30694 30695 30701 30707 30715 39745 39899 40612https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/245/12?format=asciiRadiodefaultJ/ApJS/245/12/table1Ultracompact HII region with radio continuum emissionrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLitComparison with 6.7GHz methanol masers in previous surveys (link to Table 4)meta.ref.urlintnullableMSX6CSource name (GLLL.llll+BB.bbbb)meta.id;meta.maincharprimaryNmNumber of maser(s), RRL and radio continuum measurements in this region (link to Table 5)meta.numberintnullableRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainD-6668MHz[y ] Detection, 6668MHz tracermeta.codecharD-RRLs[y ] Detection, RRLs tracermeta.codecharD-4765MHz[y ] Detection, 4765MHz tracermeta.codecharD-6030MHz[y ] Detection, 6030MHz tracermeta.codecharD-6035MHz[y ] Detection, 6035MHz tracermeta.codecharT2[y ] Is the source also listed in Table 2meta.codecharUCatDisplay data from Urquhart+, 2011, J/MNRAS/418/1689 ; 2008, J/A+A/487/253 and 2009, J/A+A/501/539meta.ref.urlintnullableSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJS/245/12/table5Properties of masers, radio recombination lines (RRLs) and radio continuum emissionrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMSX6CSource name (GLLL.llll+BB.bbbb)meta.id;meta.maincharAssocAssociated MSX6C to first MSX6C (GLLL.llll+BB.bbbb)meta.id.assoccharSLflag[s ] Sidelobe effect flag (1)meta.codecharTracerTracer (2)meta.id;phys.molcharSi[0/70795]? Integrated flux density in Tracerphot.flux.density;em.radiodoublenullablex_SiUnits for Si, depending on Tracermeta.unitcharSp[0.001/15489]? Peak flux density in Tracerphot.flux.density;em.radiodoublenullablex_SpUnits for Sp, depending on Tracermeta.unit;src.spTypecharVpeak[-64.1/116]? Velocities at peak emissionkm/sphys.velocfloatnullableVR1[-64/111]? Velocity Range, parameter 1 (3)km/sinstr.bandwidthfloatnullableVR2[-60/120.3]? Velocity Range, parameter 2 (3)km/sinstr.bandwidthfloatnullablelogLi[-2.7/6.3]? Integrated intensity, logspect.line.intensityfloatnullablex_logLiUnits for logLi, depending on Tracermeta.unitcharlogLp[-2.8/962.4]? Peak intensity, logspect.line.intensityfloatnullablex_logLpUnits for logLp, depending on Tracermeta.unitcharlogTe[4.5/7.5]? Electron temperature, loglog(K)phys.temperature.electron;phys.electronfloatnullablelogEM[6.2/10]? Emission measure, loglog(pc.cm**-6)phys.emissMeasurefloatnullableDist[0.6/18]? Distances of sourceskpcpos.distance;pos.heliocentricfloatnullablee_Dist[0.04/1.5]? Symmetric (or lower) uncertainty on Distkpcstat.errorfloatnullableE_Dist[0.27]? Upper uncertainty on Distkpcstat.error;stat.maxfloatnullableArmSpiral arm(s) (4)meta.codecharRefsReference(s) of previously known methanol masers, continuum emissions and water masers (5)meta.ref;pos.framecharJ/ApJS/245/12/table2Water maser or ammonia emission samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLitComparison with 6.7GHz methanol masers in previous surveys (link to Table 4)meta.ref.urlintnullableMSX6CSource name (GLLL.llll+BB.bbbb)meta.id;meta.maincharprimaryNmNumber of maser(s), RRL and radio continuum measurements in this region (link to Table 5)meta.numberintnullableRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainD-Water[yn ] Detection, Watermeta.codecharD-Ammonia[yn ] Detection, Ammoniameta.codecharD-6668MHz[y ] Detection, 6668MHz tracermeta.codecharD-RRLs[y ] Detection, RRLs tracermeta.codecharD-4765MHz[y ] Detection, 4765MHz tracermeta.codecharD-6030MHz[y ] Detection, 6030MHz tracermeta.codecharD-6035MHz[y ] Detection, 6035MHz tracermeta.codecharT1[y ] Is the source also listed in Table 1meta.codecharUCatDisplay data from Urquhart+, 2011, J/MNRAS/418/1689 ; 2008, J/A+A/487/253 and 2009, J/A+A/501/539meta.ref.urlintnullableSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJS/245/12/table4Comparisons of the 6.7GHz methanol masers between our survey and previous surveysrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMSX6CSource name (GLLL.llll+BB.bbbb)meta.id;meta.maincharAssocAssociated MSX6C to first MSX6C (GLLL.llll+BB.bbbb)meta.id.assoccharONameName(s) in other surveys (1)meta.idcharr_ONameReferences for sources in other surveys (2)meta.ref;pos.framecharOffsetsPosition offset(s) from MMB position (3)arcminpos;arith.diffcharNotesNotes on differences between this survey and othersmeta.notechar