SMaSH+ survey data yields the first observationally grounded distributions of key parameters for 26 hierarchical massive triples, dominated by tight inner binaries and wider tertiaries with no strong mass-separation correlations.
A Keplerian-like disk around the forming O-type star AFGL 4176
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
We present Atacama Large Millimeter/submillimeter Array (ALMA) line and continuum observations at 1.2mm with ~0.3" resolution that uncover a Keplerian-like disk around the forming O-type star AFGL 4176. The continuum emission from the disk at 1.21 mm (source mm1) has a deconvolved size of 870+/-110 AU x 330+/-300 AU and arises from a structure ~8 M_sun in mass, calculated assuming a dust temperature of 190 K. The first-moment maps, pixel-to-pixel line modeling, assuming local thermodynamic equilibrium (LTE), and position-velocity diagrams of the CH3CN J=13-12 K-line emission all show a velocity gradient along the major axis of the source, coupled with an increase in velocity at small radii, consistent with Keplerian-like rotation. The LTE line modeling shows that where CH3CN J=13-12 is excited, the temperatures in the disk range from ~70 to at least 300 K and that the H2 column density peaks at 2.8x10^24 cm^-2. In addition, we present Atacama Pathfinder Experiment (APEX) 12CO observations which show a large-scale outflow from AFGL 4176 perpendicular to the major axis of mm1, supporting the disk interpretation. Finally, we present a radiative transfer model of a Keplerian disk surrounding an O7 star, with a disk mass and radius of 12 M_sun and 2000 AU, that reproduces the line and continuum data, further supporting our conclusion that our observations have uncovered a Keplerian disk around an O-type star.
years
2026 4representative citing papers
Serendipitous discovery of a bound nine-member protostellar system in NGC 6334-43 formed by filament fragmentation, with outflows from two sources and virial masses derived for three cores.
Blue-asymmetric spectral lines appear in 50-60% of dense cores within massive dark clumps, showing that gravitational collapse operates at core scales from prestellar stages onward and supports hierarchical star formation.
New ALMA data at 50 au resolution of HH46/47 shows a rotating-infalling envelope to disk transition at 30 au around a 0.3 solar-mass protostar, with outflow shells expanding radially and supporting entrainment over disk-wind origin.
citing papers explorer
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Global and Local Infall in the ASHES Sample (GLASHES). II. Asymmetric Line Profiles around Dense Cores in 70 $\mu$m Dark Massive Clumps
Blue-asymmetric spectral lines appear in 50-60% of dense cores within massive dark clumps, showing that gravitational collapse operates at core scales from prestellar stages onward and supports hierarchical star formation.