TY - JOUR
T1 - Using the minimum spanning tree to trace mass segregation
AU - Allison, Richard J.
AU - Goodwin, Simon P.
AU - Parker, Richard J.
AU - Portegies Zwart, Simon F.
AU - De Grijs, Richard
AU - Kouwenhoven, M. B.N.
PY - 2009/5
Y1 - 2009/5
N2 - We present a new method to detect and quantify mass segregation in star clusters. It compares the minimum spanning tree (MST) of massive stars with that of random stars. If mass segregation is present, the MST length of the most massive stars will be shorter than that of random stars. This difference can be quantified (with an associated significance) to measure the degree of mass segregation. We test the method on simulated clusters in both 2D and 3D and show that the method works as expected. We apply the method to the Orion Nebula Cluster (ONC) and show that the method is able to detect the mass segregation in the Trapezium with a 'mass segregation ratio (MSR)' ΛMSR = 8.0 ± 3.5 (where ΛMSR = 1 is no mass segregation) down to 16 M⊙, and also that the ONC is mass segregated at a lower level (∼2.0 ± 0.5) down to 5 M⊙. Below 5 M ⊙ we find no evidence for any further mass segregation in the ONC.
AB - We present a new method to detect and quantify mass segregation in star clusters. It compares the minimum spanning tree (MST) of massive stars with that of random stars. If mass segregation is present, the MST length of the most massive stars will be shorter than that of random stars. This difference can be quantified (with an associated significance) to measure the degree of mass segregation. We test the method on simulated clusters in both 2D and 3D and show that the method works as expected. We apply the method to the Orion Nebula Cluster (ONC) and show that the method is able to detect the mass segregation in the Trapezium with a 'mass segregation ratio (MSR)' ΛMSR = 8.0 ± 3.5 (where ΛMSR = 1 is no mass segregation) down to 16 M⊙, and also that the ONC is mass segregated at a lower level (∼2.0 ± 0.5) down to 5 M⊙. Below 5 M ⊙ we find no evidence for any further mass segregation in the ONC.
KW - Methods: data analysis
UR - http://www.scopus.com/inward/record.url?scp=65649108088&partnerID=8YFLogxK
U2 - 10.1111/j.1365-2966.2009.14508.x
DO - 10.1111/j.1365-2966.2009.14508.x
M3 - Article
AN - SCOPUS:65649108088
SN - 0035-8711
VL - 395
SP - 1449
EP - 1454
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -