The seeds of star formation in the filamentary infrared-dark cloud G011.11–0.12

Henning, Thomas; Linz, H.; Krause, O.; Ragan, S. E.; Beuther, H.; Launhardt, R.; Nielbock, M.; Vasyunina, Tatiana

doi:10.1051/0004-6361/201014635

Cited by 120 publications

(175 citation statements)

References 27 publications

Supporting

Mentioning

163

Contrasting

Order By: Relevance

“…For example, G167.20-8.69 shows a very regular pattern with column density peaks at 0.6 pc intervals. The results are consistent with Henning et al (2010) who measured a core separation of 0.9 pc in the infrared dark cloud filament G011.11-0.12.…”

Section: Filament Structuresupporting

confidence: 92%

Galactic cold cores

Juvela

Ristorcelli

Pagani

et al. 2012

A&A

143

221

View full text Add to dashboard Cite

Context. In the project galactic cold cores we are carrying out Herschel photometric observations of cold regions of the interstellar clouds as previously identified with the Planck satellite. The aim of the project is to derive the physical properties of the population of cold clumps and to study its connection to ongoing and future star formation. Aims. We examine the cloud structure around the Planck detections in 71 fields observed with the Herschel SPIRE instrument by the summer of 2011. We wish to determine the general physical characteristics of the fields and to examine the morphology of the clouds where the cold high column density clumps are found. Methods. Using the Herschel SPIRE data, we derive colour temperature and column density maps of the fields. Together with ancillary data, we examine the infrared spectral energy distributions of the main clumps. The clouds are categorised according to their large scale morphology. With the help of recently released WISE satellite data, we look for signs of enhanced mid-infrared scattering ("coreshine"), an indication of growth of the dust grains, and have a first look at the star formation activity associated with the cold clumps. Results. The mapped clouds have distances ranging from ∼100 pc to several kiloparsecs and cover a range of sizes and masses from cores of less than 10 M to clouds with masses in excess of 10 000 M . Most fields contain some filamentary structures and in about half of the cases a filament or a few filaments dominate the morphology. In one case out of ten, the clouds show a cometary shape or have sharp boundaries indicative of compression by an external force. The width of the filaments is typically ∼0.2-0.3 pc. However, there is significant variation from 0.1 pc to 1 pc and the estimates are sensitive to the methods used and the very definition of a filament. Enhanced mid-infrared scattering, coreshine, was detected in four clouds with six additional tentative detections. The cloud LDN 183 is included in our sample and remains the best example of this phenomenon. About half of the fields are associated with active star formation as indicated by the presence of mid-infrared point sources. The mid-infrared sources often coincide with structures whose sub-millimetre spectra are still dominated by the cold dust.

show abstract

Section: Filament Structuresupporting

confidence: 92%

Galactic cold cores

Juvela

Ristorcelli

Pagani

et al. 2012

A&A

143

221

View full text Add to dashboard Cite

show abstract

“…The PDFs of the IRDCs we present all show a power-law distribution with similar slopes, regardless of their evolutionary states: G18.82-0.28 and G28.37+0.07 show bright peaks at 70 µm, and in G11.11-0.12 the presence of IR-bright protostars was demonstrated (Henning et al 2010). The IRDC G28.53-0.25 is in a very early stage because it contains no (F)IR-bright peaks.…”

Section: Discussionsupporting

confidence: 54%

Understanding star formation in molecular clouds

Schneider

Csengeri

Klessen

et al. 2015

A&A

View full text Add to dashboard Cite

We analyse column density and temperature maps derived from Herschel dust continuum observations of a sample of prominent, massive infrared dark clouds (IRDCs) i.e. G11.11-0.12, G18.82-0.28, G28.37+0.07, and G28.53-0.25. We disentangle the velocity structure of the clouds using 13 CO 1→0 and 12 CO 3→2 data, showing that these IRDCs are the densest regions in massive giant molecular clouds (GMCs) and not isolated features. The probability distribution function (PDF) of column densities for all clouds have a power-law distribution over all (high) column densities, regardless of the evolutionary stage of the cloud: G11.11-0.12, G18.82-0.28, and G28.37+0.07 contain (proto)-stars, while G28.53-0.25 shows no signs of star formation. This is in contrast to the purely log-normal PDFs reported for near and/or mid-IR extinction maps. We only find a log-normal distribution for lower column densities, if we perform PDFs of the column density maps of the whole GMC in which the IRDCs are embedded. By comparing the PDF slope and the radial column density profile of three of our clouds, we attribute the power law to the effect of large-scale gravitational collapse and to local free-fall collapse of pre-and protostellar cores for the highest column densities. A significant impact on the cloud properties from radiative feedback is unlikely because the clouds are mostly devoid of star formation. Independent from the PDF analysis, we find infall signatures in the spectral profiles of 12 CO for G28.37+0.07 and G11.11-0.12, supporting the scenario of gravitational collapse. Our results are in line with earlier interpretations that see massive IRDCs as the densest regions within GMCs, which may be the progenitors of massive stars or clusters. At least some of the IRDCs are probably the same features as ridges (high column density regions with N > 10 23 cm −2 over small areas), which were defined for nearby IR-bright GMCs. Because IRDCs are only confined to the densest (gravity dominated) cloud regions, the PDF constructed from this kind of a clipped image does not represent the (turbulence dominated) low column density regime of the cloud.

show abstract

“…The crosses in the bottom-left panel mark the positions of a double-component radio recombination line Hii region from Anderson et al (2011), the W43-MM1 position from Motte et al (2003) as well as the approximate center of the Wolf-Rayet/OB cluster (Blum et al 1999;Motte et al 2003). to search for and to study these initial conditions. Early work from the first data revealed already exciting results, e.g., we identified candidate high-mass starless cores (HMSCs) as well as weak 70 μm sources within IRDCs that may be the very first manifestation of high-mass star formation Henning et al 2010;Linz et al 2010). …”

Section: Introductionmentioning

confidence: 92%

The onset of high-mass star formation in the direct vicinity of the Galactic mini-starburst W43

Beuther

Tackenberg

Linz

et al. 2012

A&A

Self Cite

View full text Add to dashboard Cite

Context. The earliest stages of high-mass star formation are still poorly characterized. Densities, temperatures and kinematics are crucial parameters for simulations of high-mass star formation. It is also unknown whether the initial conditions vary with environment. Aims. We want to investigate the youngest massive gas clumps in the environment of extremely active star formation. Methods. We selected the IRDC 18454 complex, directly associated with the W43 Galactic mini-starburst, and observed it in the continuum emission between 70 μm and 1.2 mm with Herschel, APEX and the 30 m telescope, and in spectral line emission of N 2 H + and 13 CO with the Nobeyama 45 m, the IRAM 30 m and the Plateau de Bute Interferometer. Results. The multi-wavelength continuum study allows us to identify clumps that are infrared dark even at 70 μm and hence the best candidates to be genuine high-mass starless gas clumps. The spectral energy distributions reveal elevated temperatures and luminosities compared to more quiescent environments. Furthermore, we identify a temperature gradient from the W43 mini-starburst toward the starless clumps. We discuss whether the radiation impact of the nearby mini-starburst changes the fragmentation properties of the gas clumps and by that maybe favors more high-mass star formation in such an environment. The spectral line data reveal two different velocity components of the gas at 100 and 50 km s −1 . While chance projection is a possibility to explain these components, the projected associations of the emission sources as well as the prominent location at the Galactic bar -spiral arm interface also allow the possibility that these two components may be spatially associated and even interacting. Conclusions. High-mass starless gas clumps can exist in the close environment of very active star formation without being destroyed. The impact of the active star formation sites may even allow for more high-mass stars to form in these 2nd generation gas clumps. This particular region near the Galactic bar -spiral arm interface has a broad distribution of gas velocities, and cloud interactions may be possible.

show abstract

The seeds of star formation in the filamentary infrared-dark cloud G011.11–0.12

Cited by 120 publications

References 27 publications

Galactic cold cores

Galactic cold cores

Understanding star formation in molecular clouds

The onset of high-mass star formation in the direct vicinity of the Galactic mini-starburst W43

Contact Info

Product

Resources

About