astrophysics

Low-Metallicity Star Formation Survey in Sh2-284 (LZ-STAR): The Core Mass Function

arXiv:2607.25753

summary

The authors use ALMA 1.3 mm dust continuum observations of the low‑metallicity star‑forming region Sh2‑284 to identify dense cores and measure the core mass function, finding a high‑mass slope similar to the Salpeter IMF.

Abstract

We present an ALMA 1.3~mm dust continuum study of the dense core mass function (CMF) in Sh2-284, a low metallicity outer Galaxy star-forming complex with --. The observations cover six far-infrared bright subregions at 0.65" (3000~au) resolution. We identify a total of 91 candidate dense cores and define a robust catalog of 68 cores with Gaussian fitting. The high-mass CMF above 2.5 Msun is well described by a Salpeter-like slope, with a fiducial forward-modeled value of for . Together with existing constraints on the initial mass function (IMF) of Sh2-284, the Salpeter-like CMF is consistent with a resemblance between the CMF and IMF shapes in the outer Galaxy environments, suggesting that moderately low metallicity alone does not strongly reshape the high-mass CMF/IMF slope.

14 pages, 4 figures, submitted to ApJ, comments welcome

Topics & keywords

#star formation#low metallicity#core mass function#ALMA observations#initial mass functionALMA 1.3 mm dust continuumdense coresSalpeter slopeSh2‑284metallicity Z~0.3‑0.5 Z⊙
Low-Metallicity Star Formation Survey in Sh2-284 (LZ-STAR): The Core Mass Function · wovepaper