We present analyses of the spatial distributions of stars in the young (1–3 Myr) star-forming
regions IC 348 and NGC 1333 in the Perseus giant molecular cloud. We quantify the spatial
structure using the Q-parameter and find that both IC 348 and NGC 1333 are smooth
and centrally concentrated with Q-parameters of 0.98 and 0.89, respectively. Neither region
exhibits mass segregation (MSR = 1.1+0.2 −0.3 for IC 348 and MSR = 1.2+0.4 −0.3 for NGC 1333,
where MSR ∼ 1 corresponds to no mass segregation) nor do the most massive stars reside in
areas of enhanced stellar surface density compared to the average surface density, according
to the LDR method. We then constrain the dynamical histories and hence initial conditions
of both regions by comparing the observed values to N-body simulations at appropriate ages.
Stars in both regions likely formed with subvirial velocities that contributed to merging of substructure
and the formation of smooth clusters. The initial stellar densities were no higher than
ρ ∼ 100–500 M pc−3 for IC 348 and ρ ∼ 500–2000 M pc−3 for NGC 1333. These initial
densities, in particular that of NGC 1333, are high enough to facilitate dynamical interactions
that would likely affect ∼10 per cent of protoplanetary discs and binary stars.
Key
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)
