The remarkable 400 micron source NGC 6334/I/North/

Gezari, D. Y.

doi:10.1086/183842

Cited by 46 publications

(55 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Willis et al (2013) identified approximately 2000 young stellar objects with Spitzer and found a heavy concentration of protostars along the NGC 6334 ridge, suggesting a mini-starburst event (in agreement with the ridge definition, see Nguyen Luong et al 2011). Using a 1.2 mm continuum map, Russeil et al (2010) extracted in NGC 6334 a sample of 11 clumps, including the well-known sources I and I(N) (e.g., Gezari 1982), however, only one starless candidate was identified.…”

Section: Or (2) Colliding Flows Initiated Bysupporting

confidence: 52%

The earliest phases of high-mass star formation, as seen in NGC 6334 by Herschel-HOBYS

Tigé

Motte

Russeil

et al. 2017

A&A

View full text Add to dashboard Cite

Aims. 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. Methods. We used Herschel/PACS and SPIRE 70−500 µm images of the NGC 6334 complex complemented with (sub)millimeter and mid-infrared data. We built a complete procedure to extract ∼0.1 pc 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 2 pc × 1 pc ridge and two 0.8 pc × 0.8 pc hubs, with volume-averaged densities of ∼10 5 cm −3 . Results. A cross-correlation with high-mass star formation signposts suggests a mass threshold of 75 M for MDCs in NGC 6334. MDCs have temperatures of 9.5−40 K, masses of 75−1000 M , and densities of 1 × 10 5 −7 × 10 7 cm −3 . Their mid-infrared emission is used to separate 6 IR-bright and 10 IR-quiet protostellar MDCs while their 70 µm 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 1−7 × 10 4 yr and at most 3 × 10 5 yr respectively, suggest a dynamical scenario of high-mass star formation. Conclusions. 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.

show abstract

Section: Or (2) Colliding Flows Initiated Bysupporting

confidence: 52%

The earliest phases of high-mass star formation, as seen in NGC 6334 by Herschel-HOBYS

Tigé

Motte

Russeil

et al. 2017

A&A

View full text Add to dashboard Cite

show abstract

“…That NGC 6334I is an UC H ii region (Beuther et al 2005) while NGC 6334I(N) is an IR-quiet protostellar object (Russeil et al 2010) suggests that NGC 6334I(N) is younger than NGC 6334I. We note that the well-studied I(N) and I are (1979) and Gezari (1982).…”

Section: Observationsmentioning

confidence: 65%

TheHerschelview of the massive star-forming region NGC 6334

Russeil

Schneider

Anderson

et al. 2013

A&A

View full text Add to dashboard Cite

Aims. Fundamental to any theory of high-mass star formation are gravity and turbulence. Their relative importance, which probably changes during cloud evolution, is not known. By investigating the spatial and density structure of the high-mass star-forming complex NGC 6334 we aim to disentangle the contributions of turbulence and gravity. Methods. We used Herschel PACS and SPIRE imaging observations from the HOBYS key programme at wavelengths of 160, 250, 350, and 500 μm to construct dust temperature and column density maps. Using probability distribution functions (PDFs) of the column density determined for the whole complex and for four distinct sub-regions (distinguished on the basis of differences in the column density, temperature, and radiation field), we characterize the density structure of the complex. We investigate the spatial structure using the Δ-variance, which probes the relative amount of structure on different size scales and traces possible energy injection mechanisms into the molecular cloud. Results. The Δ-variance analysis suggests that the significant scales of a few parsec that were found are caused by energy injection due to expanding H ii regions, which are numerous, and by the lengths of filaments seen everywhere in the complex. The column density PDFs have a lognormal shape at low densities and a clearly defined power law at high densities for all sub-regions whose slope is linked to the exponent α of an equivalent spherical density distribution. In particular with α = 2.37, the central sub-region is largly dominated by gravity, caused by individual collapsing dense cores and global collapse of a larger region. The collapse is faster than free-fall (which would lead only to α = 2) and thus requires a more dynamic scenario (external compression, flows). The column density PDFs suggest that the different sub-regions are at different evolutionary stages, especially the central sub-region, which seems to be in a more evolved stage.

show abstract

“…The RCW 108 compact H ii region is known to contain a small group of stars (Straw et al 1987). The NGC 6334 molecular cloud is an extensive site of ongoing highmass star formation (McBreen et al 1979;Kraemer & Jackson 1995); we observed the regions NGC 6334 I and I(N), in the nomenclature of McBreen et al (1979) and Gezari (1982).…”

Section: Introductionmentioning

confidence: 82%

A Near-Infrared/Millimeter-Wave Study of Six Fourth-Quadrant High-Mass Star Formation Regions

Sollins

Megeath

2004

Astron J

View full text Add to dashboard Cite

We present near-infrared and millimeter-wave observations of six high-mass star-forming regions in the fourth quadrant: RCW 108, G333.6, RCW 117, RCW 122, NGC 6334 I, and G351.6. These regions have heliocentric distances of 1.3-3.0 kpc and total luminosities ranging from 0.5 to 3 ; 10 5 L . Millimeter maps taken in transitions of C 18 O, HC 3 N, 12 C 16 O, and SiO with the Swedish-ESO Submillimetre Telescope 15 m telescope detail the structure and kinematics of the clouds. Near-infrared K-band images of the same regions obtained with the MPG/ESO 2.2 m telescope are used to map the stellar surface density. The C 18 O (1 ! 0) line shows extended high column density gas, with column densities ranging from 10 22 to 3 ; 10 23 cm À2 ; in contrast, the HC 3 N (15 ! 14) emission shows eight sharply peaked dense cores. We examine these cores for recent and ongoing star formation by searching for high-velocity, non-Gaussian wings on the CO (1 ! 0) and SiO (2 ! 1) lines, peaks in the surface density of stars, and positional coincidences with IRAS point sources, as well as masers and H ii regions reported in the literature. All of the cores show evidence of ongoing star formation. NGC 6334 I(N) stands out as a unique case in which an outflow has formed and masers have appeared, but no IRAS source, K-band cluster, or UC H ii region has yet appeared; our data support previous claims that this is a rare example of a core in the earliest stages of forming a cluster of high-and low-mass stars.

show abstract

The remarkable 400 micron source NGC 6334/I/North/

Cited by 46 publications

References 0 publications

The earliest phases of high-mass star formation, as seen in NGC 6334 by Herschel-HOBYS

The earliest phases of high-mass star formation, as seen in NGC 6334 by Herschel-HOBYS

TheHerschelview of the massive star-forming region NGC 6334

A Near-Infrared/Millimeter-Wave Study of Six Fourth-Quadrant High-Mass Star Formation Regions

Contact Info

Product

Resources

About