J/ApJ/901/51ivo://CDS.VizieR/J/ApJ/901/51doi:10.26093/cds/vizier.19010051CDSAnderson L.D.Sormani M.C.Ginsburg A.Glover S.C.O.Heywood I.,Rammala I.Schuller F.Csengeri T.Urquhart J.S.Bronfman L.2023-07-21T15:08:14Z2022-02-15T15:19:35ZCDS support team

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

cds-question@unistra.frh-ii-regionsgalactic-centerinterstellar-mediumradio-continuum-emissionSgr E is a massive star formation complex found toward the Galactic center that consists of numerous discrete, compact HII regions. It is located at the intersection between the central molecular zone (CMZ) and the far dust lane of the Galactic bar, similar to "hot spots" seen in external galaxies. Compared with other Galactic star formation complexes, the Sgr E complex is unusual because its HII regions all have similar radio luminosities and angular extents, and they are deficient in ~10{mu}m emission from their photodissociation regions (PDRs). Our Green Bank Telescope radio recombination line observations increase the known membership of Sgr E to 19 HII regions. There are 43 additional HII region candidates in the direction of Sgr E, 26 of which are detected for the first time here using MeerKAT 1.28GHz data. Therefore, the true HII region population of Sgr E may number >60. Using APEX SEDIGISM ^13^CO 2->1 data we discover a 3.0x10^5^M_{sun}_ molecular cloud associated with Sgr E, but find few molecular or far-infrared concentrations at the locations of the Sgr E HII regions. Comparison with simulations and an analysis of its radio continuum properties indicate that Sgr E formed upstream in the far dust lane of the Galactic bar a few million years ago and will overshoot the CMZ, crashing into the near dust lane. We propose that the unusual infrared properties of the Sgr E HII regions are caused by their orbits about the Galactic center, which have possibly stripped their PDRs.2020ApJ...901...51Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/901/51CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/ApJS/175/509 : Ammonia spectral atlas in Perseus (Rosolowsky+, 2008)J/ApJ/690/706 : Distances of Galactic HII regions (Anderson+, 2009)J/ApJS/181/255 : CO in Galactic HII regions (Anderson+, 2009)J/ApJ/709/424 : HII regions identified with WMAPS & GLIMPSE (Murray+, 2010)J/ApJS/194/32 : HII Region Discovery Survey (HRDS). II. (Anderson+, 2011)J/ApJ/738/27 : Galactic HII regions RRL and continuum data (Balser+, 2011)J/MNRAS/418/1689 : Red MSX water maser and ammonia emissions (Urquhart+, 2011)J/ApJ/754/62 : HRDS III. HII region kinematic distances (Anderson+, 2012)J/A+A/537/A1 : Infrared fluxes of HII regions and PNe (Anderson+, 2012)J/A+A/537/A146 : Stellar models with rotation; 0.8<M<120 (Ekstrom+, 2012)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/ApJS/221/26 : Radio obs. of Galactic WISE HII regions (Anderson+, 2015)J/A+A/586/A50 : CMZ H2CO temperature maps (Ginsburg+, 2016)J/ApJ/834/57 : MW molecular clouds from ^12^CO (Miville-Deschenes+, 2017)J/A+A/601/A124 : Clouds in SEDIGISM field (Schuller+, 2017)J/A+A/624/A63 : W51 OB stars NIR spectroscopy (Bik+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/901/51https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/901/51http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/901/51https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/901/51https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/901/51http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/901/51GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/901/51/table2 (SgrE HII region radio continuum parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/901/51/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/901/51/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/901/51/table2?GETtext/xml+votable180.050000true265.47625-30.1802780.005555555555555556Cone search capability for table J/ApJ/901/51/table3 (Candidate SgrE HII region radio continuum parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/901/51/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/901/51/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/901/51/table3?GETtext/xml+votable180.050000true265.30875-30.3397220.005555555555555556Cone search capability for table J/ApJ/901/51/table4 (NH3 line parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/901/51/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/901/51/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/901/51/table4?GETtext/xml+votable180.050000true265.4756667-30.18030560.0055555555555555565/7206 6/8.481368860420881e-25 8.481368860420881e-25https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/901/51?format=asciiRadiodefaultJ/ApJ/901/51/table2SgrE HII region radio continuum parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNnh3Number of NH3 measurements for this HII region (link to Table 4)meta.numberintnullableNameName (GLLL.lll+BB.bbb; <[ABB2014] WISE GLLL.lll+BB.bbb> in Simbad)meta.id;meta.maincharRAJ2000[17] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[29/30] Degree of Declination (J2000)pos.eq.dec;meta.mainVLSR1[-217/-182.2] Velocity relative to local standard of rest (LSR)km/sphys.veloc;pos.lsrfloatVLSR2[-215.6/-5.4]? Other velocity component relative to LSRkm/sphys.veloc;pos.lsrfloatnullableDiam[0.7/7.4] Diameterpcpos.distancefloatF1.28[4.4/576.7] MeerKAT flux density at 1.28GHzmJyphot.flux.density;em.radio.750-1500MHzfloatlogNly[46.47/48.58] log of Lyman continuum luminositylog(ph.s**-1)phys.luminosityfloatSpTSpectral typesrc.spTypecharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJ/901/51/table3Candidate SgrE HII region radio continuum parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName (GLLL.lll+BB.bbb; <[ABB2014] WISE GLLL.lll+BB.bbb> in Simbad)meta.id;meta.maincharRAJ2000[17] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[29/30] Degree of Declination (J2000)pos.eq.dec;meta.mainDiam[0.6/4.1] Diameterpcpos.distancefloatF1.28[0.3/42.4] MeerKAT flux density at 1.28GHzmJyphot.flux.density;em.radio.750-1500MHzfloatlogNly[45.24/47.44] log of Lyman continuum luminositylog(ph.s**-1)phys.luminosityfloatSpTSpectral typesrc.spTypecharJ/ApJ/901/51/table4NH3 line parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName, there are multiple positions per HII regionmeta.id;meta.maincharRAJ2000[17] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[29/30] Degree of Declination (J2000)pos.eq.dec;meta.mainLineNH3 componentmeta.id;spect.linecharTmb[19.5/290.4]? Main beam brightness temperaturemKobs.paramfloatnullablee_Tmb[0.5/4]? Uncertainty in TmbmKstat.errorfloatnullableVLSR[-243.4/19.6]? Velocity relative to local standard of restkm/sphys.veloc;pos.lsrfloatnullablee_VLSR[0.1/0.2]? Uncertainty in VLSRkm/sstat.error;phys.veloc;pos.lsrfloatnullabledV[1.3/40.3]? Linewidthkm/sspect.line.widthfloatnullablee_dV[0.1/0.9]? Uncertainty in dVkm/sstat.errorfloatnullable