The Astronomical Journal | VOL. 120
Read

2MASS Observations of the Perseus, Orion A, Orion B, and Monoceros R2 Molecular Clouds

Publication Date Dec 1, 2000

Abstract

We use the 2MASS Second Incremental Release Point Source Catalog to investigate the spatial distribution of young stars in the Perseus, Orion A, Orion B, and MonR2 molecular clouds. After subtracting a semiempirical model of the field star contamination from the observed star counts, stellar surface density maps are used to identify compact clusters and any stellar population found more uniformly distributed over the molecular cloud. Each cloud contains between two and seven clusters, with at least half of the cluster population found in a single, rich cluster. In addition, a distributed stellar population is inferred in the Orion A and MonR2 molecular clouds within the uncertainties of the field star subtraction with a surface density between 0.013 and 0.083 arcmin-2. Sensitivity calculations suggest, however, that the number of stars in the distributed population may be underestimated by a factor of 2 or more if stars have been forming with a Miller-Scalo IMF at a constant star formation rate for longer than 10 Myr. After considering the possible evolutionary status of the distributed population, the global star formation efficiency implied by the sum of the distributed and cluster populations ranges between 1% and 9% among the four clouds. The fraction of the total stellar population contained in clusters for the nominal extinction model ranges from ≈50% to 100% if the distributed population is relatively young (<10 Myr), to ≈25%–70% if it is relatively old (≈100 Myr). The relatively high fraction of stars contained in cl...

Concepts

Spatial Distribution Of Young Stars Stellar Surface Density Maps Molecular Clouds Star Formation Rate Observed Star Counts Nearby Molecular Clouds Stellar Population Dense Clusters Rich Cluster Stellar Density Maps

Round-ups are the summaries of handpicked papers around trending topics published every week. These would enable you to scan through a collection of papers and decide if the paper is relevant to you before actually investing time into reading it.

Climate change Research Articles published between Nov 14, 2022 to Nov 20, 2022

R DiscoveryNov 21, 2022
R DiscoveryArticles Included:  2

The world needs to move quickly towards sustainability that should characterize all production and consumption patterns. We use cookies to improve you...

Read More

Coronavirus Pandemic

You can also read COVID related content on R COVID-19

R ProductsCOVID-19

ONE PROBLEM . ONE PURPOSE . ONE PLACE

Creating the world’s largest AI-driven & human-curated collection of research, news, expert recommendations and educational resources on COVID-19

COVID-19 Dashboard

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on “as is” basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The Copyright Law.