The Bolocam Galactic Plane Survey. Vii. Characterizing the Properties of Massive Star-Forming Regions

Dunham, Miranda K.; Rosolowsky, Erik; Evans, Neal J.; Cyganowski, C. J.; Urquhart, J. S.

doi:10.1088/0004-637x/741/2/110

Cited by 127 publications

(244 citation statements)

References 86 publications

Supporting

Mentioning

203

Contrasting

Unclassified

Order By: Relevance

“…Our results agree well with those of Dunham et al (2011), yielding similar ranges of kinetic temperature, NH 3 column density, H 2 column density, thus NH 3 abundance, and gas masses.…”

Section: Discussionsupporting

confidence: 88%

“…Dunham et al (2011) found virial parameters about a factor 2 larger than our study. While the linewidths and dust masses in both studies are comparable, Dunham et al (2011) used for their virial mass computation an "effective radius" that on average is about twice as large as the half maximum radii that we used from ATLASGAL, which accounts for this difference.…”

Section: Virial Masses and Gas Massescontrasting

confidence: 89%

See 1 more Smart Citation

Ammonia from cold high-mass clumps discovered in the inner Galactic disk by the ATLASGAL survey

Wienen

Wyrowski

Schüller

et al. 2012

A&A

208

368

View full text Add to dashboard Cite

Context. The APEX Telescope Large Area Survey: the GALaxy (ATLASGAL) is an unbiased continuum survey of the inner Galactic disk at 870 μm. It covers ±60 • in Galactic longitude and aims to find all massive clumps at various stages of high-mass star formation in the inner Galaxy, particularly the earliest evolutionary phases. Aims. We aim to determine properties such as the gas kinetic temperature and dynamics of new massive cold clumps found by ATLASGAL. Most importantly, we derived their kinematical distances from the measured line velocities. Methods. We observed the ammonia (J, K) = (1, 1) to (3, 3) inversion transitions toward 862 clumps of a flux-limited sample of submm clumps detected by ATLASGAL and extracted 13 CO (1−0) spectra from the Galactic Ring Survey (GRS). We determined distances for a subsample located at the tangential points (71 sources) and for 277 clumps whose near/far distance ambiguity is resolved. Results. Most ATLASGAL clumps are cold with rotational temperatures from 10−30 K with a median of 17 K. They have a wide range of NH 3 linewidths (1−7 km s −1 ) with 1.9 km s −1 as median, which by far exceeds the thermal linewidth, as well as a broad distribution of high column densities from 10 14 to 10 16 cm −2 (median of 2 × 10 15 cm −2 ) with an NH 3 abundance in the range of 5 to 30 × 10 −8 . ATLASGAL sources are massive, > ∼ 100 M , and a fraction of clumps with a broad linewidth is in virial equilibrium. We found an enhancement of clumps at Galactocentric radii of 4.5 and 6 kpc. The comparison of the NH 3 lines as high-density probes with the GRS 13 CO emission as low-density envelope tracer yields broader linewidths for 13 CO than for NH 3 . The small differences in derived clump velocities between NH 3 (representing dense core material) and 13 CO (representing more diffuse molecular cloud gas) suggests that the cores are essentially at rest relative to the surrounding giant molecular cloud. Conclusions. The high detection rate (87%) confirms ammonia as an excellent probe of the molecular content of the massive, cold clumps revealed by ATLASGAL. A clear trend of increasing rotational temperatures and linewidths with evolutionary stage is seen for source samples ranging from 24 μm dark clumps to clumps with embedded HII regions. The survey provides the largest ammonia sample of high-mass star forming clumps and thus presents an important repository for the characterization of statistical properties of the clumps and the selection of subsamples for detailed, high-resolution follow-up studies.

show abstract

“…Our results agree well with those of Dunham et al (2011), yielding similar ranges of kinetic temperature, NH 3 column density, H 2 column density, thus NH 3 abundance, and gas masses.…”

Section: Discussionsupporting

confidence: 88%

Section: Virial Masses and Gas Massescontrasting

confidence: 89%

Ammonia from cold high-mass clumps discovered in the inner Galactic disk by the ATLASGAL survey

Wienen

Wyrowski

Schüller

et al. 2012

A&A

208

368

View full text Add to dashboard Cite

show abstract

“…None of these fragmentary sources currently is massive enough to form an O-type star. However, the total massM 10 tot 3 M ☉ of each hub is of the same order as that of very massive cores observed in other IRDCs, many of which harbor protoclusters with luminosities exceeding any of the protoclusters in M17 SWex (Dunham et al 2011a(Dunham et al , 2011b. The lower-density halo surrounding the IRDCs represents an enormous mass reservoir containing the bulk of the >2 10 5 M ☉ measured by CO observations of M17 SWex (Elmegreen et al 1979).…”

Section: Prospects For Future Massive Star Formation In M17 Swexmentioning

confidence: 74%

RAPID CIRCUMSTELLAR DISK EVOLUTION AND AN ACCELERATING STAR FORMATION RATE IN THE INFRARED DARK CLOUD M17 SWex

Povich

Townsley

Robitaille

et al. 2016

ApJ

View full text Add to dashboard Cite

We present a catalog of 840 X-ray sources and first results from a 100 ks Chandra X-ray Observatory imaging study of the filamentary infrared (IR) dark cloud G014.225-00.506, which forms the central regions of a larger cloud complex known as the M17 southwest extension (M17 SWex). In addition to the rich population of protostars and young stellar objects with dusty circumstellar disks revealed by archival data from the Spitzer Space Telescope, we discover a population of X-ray-emitting, intermediate-mass pre-main-sequence stars that lack IR excess emission from circumstellar disks. We model the IR spectral energy distributions of this source population to measure its mass function and place new constraints on the destruction timescales for the inner dust disk for 2-8 M ☉ stars. We also place a lower limit on the star formation rate (SFR) and find that it is quite high (  M 0.007 M ☉ yr −1 ), equivalent to several Orion Nebula Clusters in G14.225-0.506 alone, and likely accelerating. The cloud complex has not produced a population of massive, O-type stars commensurate with its SFR. This absence of very massive (20 M ☉ ) stars suggests that either (1) M17 SWex is an example of a distributed mode of star formation that will produce a large OB association dominated by intermediate-mass stars but relatively few massive clusters, or (2) the massive cores are still in the process of accreting sufficient mass to form massive clusters hosting O stars.

show abstract

“…Rosolowsky et al (2010) adopted a value of 2.4, which is the median of the values derived from a range of models, however, they note that the value of η can vary by a factor of 2 in their simulations. For consistency and to facilitate comparisons between the BGPS and ATLASGAL catalogues we also adopt this value, which is approximately equivalent to the sources effective radius (i.e., R eff = √ (A/π), where A is the surface area of the source; Dunham et al 2011).…”

Section: Catalogue Descriptionmentioning

confidence: 99%

ATLASGAL – compact source catalogue: 330° < ℓ < 21°

Contreras

Schüller

Urquhart

et al. 2012

A&A

239

325

View full text Add to dashboard Cite

Context. The APEX Telescope Large Area Survey of the GALaxy (ATLASGAL) is the first systematic survey of the inner Galactic plane in the sub-millimetre. The observations were carried out with the Large APEX Bolometer Camera (LABOCA), an array of 295 bolometers observing at 870 μm (345 GHz). Aims. Here we present a first version of the compact source catalogue extracted from this survey. This catalogue provides an unbiased database of dusty clumps in the inner Galaxy. Methods. The construction of this catalogue was made using the source extraction routine SExtractor. We have cross-associated the obtained sources with the IRAS and MSX catalogues, in order to constrain their nature. Results. We have detected 6639 compact sources in the range from 330 ≤ ≤ 21 degrees and |b| ≤ 1.5 degrees. The catalogue has a 99% completeness for sources with a peak flux above 6σ, which corresponds to a flux density of ∼0.4 Jy beam −1 . The parameters extracted for sources with peak fluxes below the 6σ completeness threshold should be used with caution. Tests on simulated data find the uncertainty in the flux measurement to be ∼12%, however, in more complex regions the flux values can be overestimated by a factor of 2 due to the additional background emission. Using a search radius of 30 we found that 40% of ATLASGAL compact sources are associated with an IRAS or MSX point source, but, ∼50% are found to be associated with MSX 21 μm fluxes above the local background level, which is probably a lower limit to the actual number of sources associated with star formation. Conclusions. Although infrared emission is found towards the majority of the clumps detected, this catalogue is still likely to include a significant number of clumps that are devoid of star formation activity and therefore excellent candidates for objects in the coldest, earliest stages of (high-mass) star formation.

show abstract

The Bolocam Galactic Plane Survey. Vii. Characterizing the Properties of Massive Star-Forming Regions

Cited by 127 publications

References 86 publications

Ammonia from cold high-mass clumps discovered in the inner Galactic disk by the ATLASGAL survey

Ammonia from cold high-mass clumps discovered in the inner Galactic disk by the ATLASGAL survey

RAPID CIRCUMSTELLAR DISK EVOLUTION AND AN ACCELERATING STAR FORMATION RATE IN THE INFRARED DARK CLOUD M17 SWex

ATLASGAL – compact source catalogue: 330° < ℓ < 21°

Contact Info

Product

Resources

About