J/A+A/602/A77 HOBYS: 46 MDCs found in NGC 6334 (Tige+, 2017) ================================================================================ The earliest phases of high-mass star formation, as seen in NGC 6334 by Herschel-HOBYS. Tige J., Motte F., Russeil D., Zavagno A., Hennemann M., Schneider N., Hill T., Nguyen Luong Q., Di Francesco J., Bontemps S., Louvet F., Didelon P., Konyves V., Andre P., Leuleu G., Bardagi J., Anderson L.D., Arzoumanian D., Benedettini M., Bernard J.-P., Elia D., Figueira M., Kirk J., Martin P.G., Minier V., Molinari S., Nony T., Persi P., Pezzuto S., Polychroni D., Rayner T., Rivera-Ingraham A., Roussel H., Rygl K., Spinoglio L., White G.J. =2017A&A...602A..77T (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Molecular clouds ; Photometry, millimetric/submm Keywords: dust, extinction - ISM: clouds - stars: formation - submillimeter: ISM - stars: protostars - ISM: individual: NGC 6334 Abstract: To constrain models of high-mass star formation, the Herschel-HOBYS key program aims at discovering massive dense cores (MDCs) able to host the high-mass analogs of low-mass prestellar cores, which have been searched for over the past decade. We here focus on NGC 6334, one of the best-studied HOBYS molecular cloud complexes. We used Herschel/PACS and SPIRE 70-500{mu}m images of the NGC 6334 complex complemented with (sub)millimeter and mid-infrared data. We built a complete procedure to extract ~0.1pc dense cores with the getsources software, which simultaneously measures their far-infrared to millimeter fluxes. We carefully estimated the temperatures and masses of these dense cores from their spectral energy distributions (SEDs). We also identified the densest pc-scale cloud structures of NGC 6334, one 2pcx1pc ridge and two 0.8pcx0.8pc hubs, with volume-averaged densities of ~10^5^cm^-3^. A cross-correlation with high-mass star formation signposts suggests a mass threshold of 75M_{sun}_ for MDCs in NGC 6334. MDCs have temperatures of 9.5-40K, masses of 75-1000M_{sun}_, and densities of 1x10^5^-7x10^7^cm^-3^. Their mid-infrared emission is used to separate 6 IR-bright and 10 IR-quiet protostellar MDCs while their 70{mu}m emission strength, with respect to fitted SEDs, helps identify 16 starless MDC candidates. The ability of the latter to host high-mass prestellar cores is investigated here and remains questionable. An increase in mass and density from the starless to the IR-quiet and IR-bright phases suggests that the protostars and MDCs simultaneously grow in mass. The statistical lifetimes of the high-mass prestellar and protostellar core phases, estimated to be 1-7x10^4^yr and at most 3x10^5^yr respectively, suggest a dynamical scenario of high-mass star formation. The present study provides good mass estimates for a statistically significant sample, covering the earliest phases of high-mass star formation. High-mass prestellar cores may not exist in NGC 6334, favoring a scenario presented here, which simultaneously forms clouds, ridges, MDCs, and high-mass protostars. Description: Fluxes and information for the 46 MDCs found in NGC 6334 File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file catalog.dat 555 46 Information and fluxes of the 46 MDCs (tables A1-A12) table3.dat 51 46 Physical parameters of the 46 MDCs found in NGC 6334 list.dat 145 11 List of FITS images fits/* . 11 Individual FITS images -------------------------------------------------------------------------------- See also: J/ApJS/69/99 : NGC 6334 centers of star formation JHK photom. (Straw+ 1989) J/A+A/316/102 : JHK Photometry in NGC 6334 (Tapia+, 1996) J/A+A/357/1020 : JHK photometry in NGC 6334. IV (Persi+, 2000) J/ApJ/668/906 : Massive clumps in NGC 6334 (Munoz+, 2007) J/A+A/481/169 : ATCA 3mm obs. of NGC 6334I and NGC 6334I(N) (Beuther+, 2008) J/AJ/136/2083 : NGC 6334 clumps from 450/850um observations (Matthews+, 2009) J/AJ/138/227 : Stellar clusters in NGC 6334 complex (Feigelson+, 2009) J/ApJ/707/1 : Water and Methanol masers in NGC 6334I(N) (Brogan+, 2009) J/A+A/515/A55 : NGC 6334-NGC 6357 complex (Russeil+, 2010) J/A+A/538/A142 : OB stars in NGC 6334 and NGC 6357 (Russeil+, 2012) J/ApJ/778/96 : Spitzer and NEWFIRM observations of NGC 6334 (Willis+, 2013) J/A+A/587/A135 : Halpha images of NGC 6334 and NGC 6357 (Russeil+, 2016) J/A+A/592/A54 : Combined ArTeMiS+SPIRE 350um image of NGC6334 (Andre+, 2016) J/A+A/593/A37 : Spectral cube toward NGC 6334 I and I(N) (van der Wiel+, 2016) Byte-by-byte Description of file: catalog.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 2 I2 --- Number [1/46] getsources number 4- 18 A15 --- Name HOBYS_J name (HHMMSS.s+DDMMSS) 20- 21 I2 h RAh Right ascension (J2000.0) 23- 24 I2 min RAm Right ascension (J2000.0) 26- 30 F5.2 s RAs Right ascension (J2000.0) 32 A1 --- DE- Declination sign (J2000.0) 33- 34 I2 deg DEd Declination (J2000.0) 36- 37 I2 arcmin DEm Declination (J2000.0) 39- 42 F4.1 arcsec DEs Declination (J2000.0) 44 A1 --- Flag70 Fluxes reliability and upper limit flag (1) 46- 51 F6.1 Jy/beam Sp70 ? Peak intensity at 70um 53- 56 F4.1 Jy/beam e_Sp70 ? Peak intensity uncertainty 58- 64 F7.1 Jy Si70 ? Integrated flux at 70um 66- 69 F4.1 Jy e_Si70 ? Integrated flux uncertainty 71- 74 F4.1 arcsec AMAJ70 ? FWHM major axis 76- 79 F4.1 arcsec AMIN70 ? FWHM minor axis 81- 83 I3 deg PA70 ? Position angle 85 A1 --- Flag160 Fluxes reliability and upper limit flag (1) 87- 92 F6.1 Jy/beam Sp160 ? Peak intensity at 160um 94- 97 F4.1 Jy/beam e_Sp160 ? Peak intensity uncertainty 99-104 F6.1 Jy Si160 ? Integrated flux at 160um 106-110 F5.1 Jy e_Si160 ? Integrated flux uncertainty 112-115 F4.1 arcsec AMAJ160 ? FWHM major axis 117-120 F4.1 arcsec AMIN160 ? FWHM minor axis 122-124 I3 deg PA160 ? Position angle 126 A1 --- Flag250 Fluxes reliability and upper limit flag (1) 128-133 F6.1 Jy/beam Sp250 Peak intensity at 250um 135-138 F4.1 Jy/beam e_Sp250 Peak intensity uncertainty 140-145 F6.1 Jy Si250 Integrated flux at 250um 147-150 F4.1 Jy e_Si250 Integrated flux uncertainty 152-155 F4.1 arcsec AMAJ250 FWHM major axis 157-160 F4.1 arcsec AMIN250 FWHM minor axis 162-164 I3 deg PA250 Position angle 166 A1 --- Flag350 Fluxes reliability and upper limit flag (1) 168-173 F6.1 Jy/beam Sp350 Peak intensity at 350um 175-178 F4.1 Jy/beam e_Sp350 Peak intensity uncertainty 180-185 F6.1 Jy Si350 Integrated flux at 350um 187-190 F4.1 Jy e_Si350 Integrated flux uncertainty 192-195 F4.1 arcsec AMAJ350 FWHM major axis 197-200 F4.1 arcsec AMIN350 FWHM minor axis 202-206 F5.1 deg PA350 Position angle 208 A1 --- Flag500 Fluxes reliability and upper limit flag (1) 210-214 F5.1 Jy/beam Sp500 Peak intensity at 500um 216-219 F4.1 Jy/beam e_Sp500 Peak intensity uncertainty 221-225 F5.1 Jy Si500 Integrated flux at 500um 227-230 F4.1 Jy e_Si500 Integrated flux uncertainty 232-235 F4.1 arcsec AMAJ500 FWHM major axis 237-240 F4.1 arcsec AMIN500 FWHM minor axis 242-244 I3 deg PA500 Position angle 246-282 A37 --- GName GLIMPSE identification 285-290 F6.4 Jy Si3.6 ? Integrated flux at 3.6 mic 291 A1 --- f_Si3.6 [*] * indicate it is an aperture photometry 293-298 F6.4 Jy Si4.5 ? Integrated flux at 4.5 mic 299 A1 --- f_Si4.5 [*] * indicate it is an aperture photometry 301-305 F5.3 Jy Si5.8 ? Integrated flux at 5.8 mic 306 A1 --- f_Si5.8 [*] * indicate it is an aperture photometry 308-313 F6.3 Jy Si8.0 ? Integrated flux at 8.0 mic 314 A1 --- f_Si8.0 [*] * indicate it is an aperture photometry 316-333 A18 --- nameMG MIPSGAL identification 337-341 F5.3 Jy Si24 ? Integrated flux at 24 mic 342 A1 --- f_Si24 [*] * indicate it is an aperture photometry 348-370 A23 --- nameMSX MSX identification 372-376 F5.1 Jy Si21 ? Integrated flux at 21 mic 377-395 A19 --- nameW WISE identification 397-400 F4.1 Jy Si22 ? Integrated flux at 22 mic 402 A1 --- Flag450 Fluxes reliability and upper limit flag (1) 404-408 F5.2 Jy/beam Sp450 ? Peak intensity at 450um 410-412 F3.1 Jy/beam e_Sp450 ? Peak intensity uncertainty 414-418 F5.1 Jy Si450 ? Integrated flux at 450um 420-423 F4.1 Jy e_Si450 ? Integrated flux uncertainty 425-428 F4.1 arcsec AMAJ450 ? FWHM major axis 430-433 F4.1 arcsec AMIN450 ? FWHM minor axis 435-437 I3 deg PA450 ? Position angle 439 A1 --- Flag850 Fluxes reliability and upper limit flag (1) 441-445 F5.2 Jy/beam Sp850 ? Peak intensity at 850um 447-450 F4.2 Jy/beam e_Sp850 ? Peak intensity uncertainty 452-456 F5.2 Jy Si850 ? Integrated flux at 850um 458-461 F4.2 Jy e_Si850 ? Integrated flux uncertainty 463-466 F4.1 arcsec AMAJ850 ? FWHM major axis 468-471 F4.1 arcsec AMIN850 ? FWHM minor axis 473-475 I3 deg PA850 ? Position angle 477 A1 --- Flag870 Fluxes reliability and upper limit flag (1) 479-483 F5.2 Jy/beam Sp870 ? Peak intensity at 870um 485-488 F4.2 Jy/beam e_Sp870 ? Peak intensity uncertainty 490-494 F5.2 Jy Si870 ? Integrated flux at 870um 495-499 F5.2 Jy e_Si870 ? Integrated flux uncertainty 501-504 F4.1 arcsec AMAJ870 ? FWHM major axis 506-509 F4.1 arcsec AMIN870 ? FWHM minor axis 511-513 I3 deg PA870 ? Position angle 515 A1 --- Flag1200 Fluxes reliability and upper limit flag (1) 517-522 F6.3 Jy/beam Sp1200 ? Peak intensity at 1200um 524-528 F5.3 Jy/beam e_Sp1200 ? Peak intensity uncertainty 530-535 F6.3 Jy Si1200 ? Integrated flux at 1200um 536-541 F6.3 Jy e_Si1200 ? Integrated flux uncertainty 543-546 F4.1 arcsec AMAJ1200 ? FWHM major axis 548-551 F4.1 arcsec AMIN1200 ? FWHM minor axis 553-555 I3 deg PA1200 ? Position angle -------------------------------------------------------------------------------- Note (1): Flags as follows: 0 = unreliable flux because the source is too weak 1 = reliable flux 2 = unreliable flux because the source is too large and/or too elliptical -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 A3 --- Sample Sample (1) 5- 6 I2 --- Number getsources number 8- 9 A2 --- l_FWHM [<= ] Limit flag on FWHM 10- 13 F4.2 pc FWHM Deconvolved FWHM 15- 18 F4.1 K Tdust Mean dust temperature 20- 22 F3.1 K e_Tdust mrs uncertainty on Tdust 24- 27 I4 Msun Mass Mass 29- 31 I3 Msun e_Mass rms uncertainty on Mass 33- 37 I5 Lsun Lbol Bolometric luminosity 39- 40 A2 --- n_nH2 [>= ] Limit flag on nH2 41- 46 E6.2 cm-2 nH2 Mean molecular hydrogen column density 48- 51 F4.1 --- chi2 chi^2^ value -------------------------------------------------------------------------------- Note (1): Sample as follows: IRb = IR-bright protostellar MDC IRq = IR-quiet protostellar MDC S = Starless MDC candidate U = Undefined cloud structure -------------------------------------------------------------------------------- Byte-by-byte Description of file: list.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 9 F9.5 deg RAdeg Right Ascension of center (J2000) 10- 18 F9.5 deg DEdeg Declination of center (J2000) 20- 23 I4 --- Nx Number of pixels along X-axis 25- 28 I4 --- Ny Number of pixels along Y-axis 30- 33 I4 um lambda ? Observed wavelength 35- 41 A7 --- Unit Image unit 43- 47 I5 Kibyte size Size of FITS file 49- 87 A39 --- FileName Name of FITS file, in subdirectory fits 89-145 A57 --- Title Title of the FITS file -------------------------------------------------------------------------------- Acknowledgements: We are grateful to Alexander Men'shchikov for his help and discussions on getsources. SPIRE has been developed by a consortium of institutes led by Cardiff Univ. (UK) and including Univ. Lethbridge (Canada); NAOC (China); CEA, LAM (France); IFSI, Univ. Padua (Italy); IAC (Spain); Stockholm Observatory (Sweden); Imperial College London, RAL, UCL-MSSL, UKATC, Univ. Sussex (UK); and Caltech, JPL, NHSC, Univ. Colorado (USA). This development has been supported by national funding agencies: CSA (Canada); NAOC (China); CEA, CNES, CNRS (France); ASI (Italy); MCINN (Spain); SNSB (Sweden); STFC, UKSA (UK); and NASA (USA). PACS has been developed by a consortium of institutes led by MPE (Germany) and including UVIE (Austria); KU Leuven, CSL, IMEC (Belgium); CEA, LAM (France); MPIA (Germany); INAFIFSI/ OAA/OAP/OAT, LENS, SISSA (Italy); IAC (Spain). This development has been supported by the funding agencies BMVIT (Austria), ESA-PRODEX (Belgium), CEA/CNES (France), DLR (Germany), ASI/INAF (Italy), and CICYT/MCYT (Spain). This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France. Part of this work was supported by the ANR (Agence Nationale pour la Recherche) project PROBeS, number ANR-08-BLAN-0241. We acknowledge financial support from "Programme National de Physique Stellaire (PNPS) and program 'Physique et Chime du Milieu Interstellaire' (PCMI) of CNRS/INSU, France. GJW gratefully acknowledges the receipt of a Leverhulme Emeritus Professorial Fellowship. Delphine Russeil, delphine.russeil(at)lam.fr References: Motte et al., 2010A&A...518L..77M, Initial highlights of the HOBYS key program, the Herschel imaging survey of OB young stellar objects. History: * 28-Aug-2017: online version * 26-Nov-2018: columns "nameW Si22" and "nameMSX Si21" interverted in original file, now corrected. ================================================================================ (End) Patricia Vannier [CDS] 28-Aug-2017