2025ApJ...980...44Z


Query : 2025ApJ...980...44Z

2025ApJ...980...44Z - Astrophys. J., 980, 44 (2025/February-2)

ALMA Observations of Massive Clouds in the Central Molecular Zone: External-pressure-confined Dense Cores and Salpeter-like Core Mass Functions.

ZHANG Z., LU X., LIU T., QIN S.-L., GINSBURG A., CHENG Y., LIU H.B., WALKER D.L., TANG X., LI S., ZHANG Q., PILLAI T., KAUFFMANN J., BATTERSBY C., FENG S., ZHANG S., GU Q.-L., XU F., JIAO W., LIU X., CHEN L., LUO Q.-Y., MAI X., LI Z.-Y., YANG D., SHEN X., LIU M. and SHEN Z.

Abstract (from CDS):

We present Atacama Large Millimeter/submillimeter Array Band 6 (1.3 mm) observations of dense cores in three massive molecular clouds within the central molecular zone (CMZ) of the Milky Way, including the Dust Ridge cloud e, Sgr C, and the 20 km s–1 cloud, at a spatial resolution of 2000 au. Among the 834 cores identified from the 1.3 mm continuum, we constrain temperatures and linewidths of 253 cores using local thermodynamic equilibrium methods to fit the H2CO and/or CH3CN spectra. We determine their masses using the 1.3 mm dust continuum and derived temperatures, and then evaluate their virial parameters using the H2CO and/or CH3CN linewidths and construct the core mass functions (CMFs). We find that the contribution of external pressure is crucial for the virial equilibrium of the dense cores in the three clouds, which contrasts with the environment in the Galactic disk where dense cores are already bound, even without the contribution of external pressure. With our new temperature estimates we also find that the CMFs show a Salpeter-like slope in the high-mass (≳3-6 M⊙) end, a change from previous works. Combined with the possible top-heavy initial mass functions (IMFs) in the CMZ, our result suggests that gas accretion and further fragmentation may play important roles in transforming the CMF to the IMF.

Abstract Copyright: © 2025. The Author(s). Published by the American Astronomical Society.

Journal keyword(s): Galactic center - Star formation - Molecular clouds

Status at CDS : Large table(s) will be appraised for possible ingestion in VizieR.

Simbad objects: 4

goto Full paper

goto View the references in ADS

Number of rows : 4
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2026
#notes
1 NAME Sgr C MoC 17 44 36.3 -29 28 13           ~ 400 0
2 GCM -0.13 -0.08 MoC 17 45 25.2 -29 05 30           ~ 141 1
3 NAME Galactic Center reg 17 45 39.60213 -29 00 22.0000           ~ 16269 0
4 GAL 000.478-00.005 MoC 17 46 46 -28 31.8           ~ 15 0

To bookmark this query, right click on this link: simbad:objects in 2025ApJ...980...44Z and select 'bookmark this link' or equivalent in the popup menu