A Population of Cold Cores in the Galactic Plane

Egan, M. P.; Shipman, R.; Price, S. D.; Carey, Sean; Clark, F. O.; Cohen, Martin

doi:10.1086/311198

Cited by 392 publications

(378 citation statements)

References 11 publications

Supporting

Mentioning

364

Contrasting

Order By: Relevance

“…Details of the instrumentation (sensitivity, scan rate, calibration, etc.) are given by Egan et al (1998), and a description of the astronomical experiments on MSX is given by Price (1995). Figure 1a shows the MSX band A ( mm) data presented in false color with Dl = 6.8-10.8 the horizontal direction parallel to the Galactic plane.…”

Section: Observations and Resultsmentioning

confidence: 99%

Large-Scale Structure of the Carina Nebula

Smith

Egan

Carey

et al. 2000

The Astrophysical Journal

148

View full text Add to dashboard Cite

Observations obtained with the Midcourse Space Experiment (MSX) satellite reveal for the first time the complex mid-infrared morphology of the entire Carina Nebula (NGC 3372). On the largest size scale of ∼100 pc, the thermal infrared emission from the giant H ii region delineates one coherent structure: a (somewhat distorted) bipolar nebula with the major axis perpendicular to the Galactic plane. The Carina Nebula is usually described as an evolved H ii region that is no longer actively forming stars, clearing away the last vestiges of its natal molecular cloud. However, the MSX observations presented here reveal numerous embedded infrared sources that are good candidates for sites of current star formation. Several compact infrared sources are located at the heads of dust pillars or in dark globules behind ionization fronts. Because their morphology suggests a strong interaction with the peculiar collection of massive stars in the nebula, we speculate that these new infrared sources may be sites of triggered star formation in NGC 3372.

show abstract

Section: Observations and Resultsmentioning

confidence: 99%

Large-Scale Structure of the Carina Nebula

Smith

Egan

Carey

et al. 2000

The Astrophysical Journal

148

View full text Add to dashboard Cite

show abstract

“…IRDCs were intially discovered by the ISO (Perault et al 1996) and MSX (Carey et al 1998;Egan et al 1998) surveys as regions of high contrast against the mid-infrared (MIR) background. The densest IRDCs may eventually form massive stars, Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.…”

Section: Introductionmentioning

confidence: 99%

The initial conditions of high-mass star formation: radiative transfer models of IRDCs seen in theHerschelHi-GAL survey

Wilcock

Kirk

Stamatellos

et al. 2011

A&A

View full text Add to dashboard Cite

The densest infrared dark clouds (IRDCs) may represent the earliest observable stage of high-mass star formation. These clouds are very cold, hence they emit mainly at far-infrared and sub-mm wavelengths. For the first time, Herschel has provided multi-wavelength, spatially resolved observations of cores within IRDCs, which, when combined with radiative transfer modelling, can constrain their properties, such as mass, density profile and dust temperature. We use a 3D, multi-wavelength Monte Carlo radiative transfer code to model in detail the emission from six cores in three typical IRDCs seen in the Hi-GAL survey (G030.50+00.95, G031.03+00.26 and G031.03+00.76), and thereby to determine the properties of these cores and compare them with their low-mass equivalents. We found masses ranging from 90 to 290 M with temperatures from 8 to 11 K at the centre of each core and 18 to 28 K at the surface. The maximum luminosity of an embedded star within each core was calculated, and we rule out the possibility of significant high mass star formation having yet occurred in three of our cores.

show abstract

“…Because high-mass stars are rare, they are on average at large distances, thus angular resolution is of paramount importance. With the advent of Spitzer Space Telescope and Herschel Space Observatory (Pilbratt et al 2010), coupled with extensive ground-based survey efforts, we now can approach this observational task statistically.Ever since their discovery in absorption in mid-infrared Galactic plane surveys, ISO data (Perault et al 1996) and MSX observations (Egan et al 1998), infrared-dark clouds (IRDCs) have been subject to intense study because they are the cold (T < 20 K), dense (n > 10 4 cm −3 ) environments believed to be required for the formation of high-mass stars and clusters (cf. Rathborne et al 2006;Ragan et al 2009;Battersby et al 2010).…”

mentioning

confidence: 99%

APEX/SABOCA observations of small-scale structure of infrared-dark clouds

Ragan

Henning

Beuther

2013

A&A

View full text Add to dashboard Cite

Infrared-dark clouds (IRDCs) harbor the early phases of cluster and high-mass star formation and are comprised of cold (∼20 K), dense (n > 10 4 cm −3 ) gas. The spectral energy distribution (SED) of IRDCs is dominated by the far-infrared and millimeter wavelength regime, and our initial Herschel study examined IRDCs at the peak of the SED with high angular resolution. Here we present a follow-up study using the SABOCA instrument on APEX which delivers 7.8 angular resolution at 350 µm, matching the resolution we achieved with Herschel/PACS, and allowing us to characterize substructure on ∼0.1 pc scales. Our sample of 11 nearby IRDCs are a mix of filamentary and clumpy morphologies, and the filamentary clouds show significant hierarchical structure, while the clumpy IRDCs exhibit little hierarchical structure. All IRDCs, regardless of morphology, have about 14% of their total mass in small scale core-like structures which roughly follow a trend of constant volume density over all size scales. Out of the 89 protostellar cores we identified in this sample with Herschel, we recover 40 of the brightest and re-fit their SEDs and find their properties agree fairly well with our previous estimates ( T ∼ 19 K). We detect a new population of "cold cores" which have no 70 µm counterpart, but are 100 and 160 µm-bright, with colder temperatures ( T ∼ 16 K). This latter population, along with SABOCA-only detections, are predominantly low-mass objects, but their evolutionary diagnostics are consistent with the earliest starless or prestellar phase of cores in IRDCs.Key words. catalogs -stars: formation -ISM: structure -submillimeter: ISM Background and motivationDespite the importance of high-mass stars to the energy budget of galaxies, their formation remains a major open question in astronomy (Zinnecker & Yorke 2007). A major hindrance to progress is the inherent difficulty in obtaining well-defined initial conditions observationally. Because high-mass stars are rare, they are on average at large distances, thus angular resolution is of paramount importance. With the advent of Spitzer Space Telescope and Herschel Space Observatory (Pilbratt et al. 2010), coupled with extensive ground-based survey efforts, we now can approach this observational task statistically.Ever since their discovery in absorption in mid-infrared Galactic plane surveys, ISO data (Perault et al. 1996) and MSX observations (Egan et al. 1998), infrared-dark clouds (IRDCs) have been subject to intense study because they are the cold (T < 20 K), dense (n > 10 4 cm −3 ) environments believed to be required for the formation of high-mass stars and clusters (cf. Rathborne et al. 2006;Ragan et al. 2009;Battersby et al. 2010). They are located throughout the Galactic plane, concentrated within the spiral arms (Jackson et al. 2008). The formation of IRDCs, their kinematic structure and population of Based on observations carried out with the Atacama Pathfinder Experiment (APEX). APEX is a collaboration between Max Planck Institut für Radioastronomie (MPIf...

show abstract

A Population of Cold Cores in the Galactic Plane

Cited by 392 publications

References 11 publications

Large-Scale Structure of the Carina Nebula

Large-Scale Structure of the Carina Nebula

The initial conditions of high-mass star formation: radiative transfer models of IRDCs seen in theHerschelHi-GAL survey

APEX/SABOCA observations of small-scale structure of infrared-dark clouds

Contact Info

Product

Resources

About