Investigating the structure of star-forming regions using INDICATE

Author(s)
George A. Blaylock-Squibbs, Richard J. Parker, Anne S. M. Buckner, Manuel Güdel
Abstract

The ability to make meaningful comparisons between theoretical and observational data of star-forming regions is key to understanding the star formation process. In this paper, we test the performance of INDICATE, a new method to quantify the clustering tendencies of individual stars in a region, on synthetic star-forming regions with substructured, and smooth, centrally concentrated distributions. INDICATE quantifies the amount of stellar affiliation of each individual star, and also determines whether this affiliation is above random expectation for the star-forming region in question. We show that INDICATE cannot be used to quantify the overall structure of a region due to a degeneracy when applied to regions with different geometries. We test the ability of INDICATE to detect differences in the local stellar surface density and its ability to detect and quantify mass segregation. We then compare it to other methods such as the mass segregation ratio Lambda(MSR), the local stellar surface density ratio Sigma(LDR), and the cumulative distribution of stellar positions. INDICATE detects significant differences in the clustering tendencies of the most massive stars when they are at the centre of a smooth, centrally concentrated distribution, corresponding to areas of greater stellar surface density. When applied to a subset of the 50 most massive stars, we show INDICATE can detect signals of mass segregation. We apply INDICATE to the following nearby star-forming regions: Taurus, ONC, NGC 1333, IC 348, and rho Ophiuchi and find a diverse range of clustering tendencies in these regions.

Organisation(s)
Department of Astrophysics
External organisation(s)
University of Sheffield, University of Exeter
Journal
Monthly Notices of the Royal Astronomical Society
Volume
510
Pages
2864-2882
No. of pages
19
ISSN
0035-8711
DOI
https://doi.org/10.1093/mnras/stab3447
Publication date
02-2022
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/357e0b66-f133-4e92-820f-39918181d298