Star clusters stand at the intersection of much of modern astrophysics: the ISM, gravitational
dynamics, stellar evolution, and cosmology. Here, we review observations and theoretical …

Star-forming gas clouds are strongly magnetized, and their ionization fractions are high
enough to place them close to the regime of ideal magnetohydrodyamics on all but the …

We present PHANGS–ALMA, the first survey to map CO J= 2→ 1 line emission at∼ 1''∼ 100
pc spatial resolution from a representative sample of 90 nearby (d≲ 20 Mpc) galaxies that lie …

The physics of star formation and the deposition of mass, momentum and energy into the
interstellar medium by massive stars ('feedback') are the main uncertainties in modern …

We present a unified description of the scenario of global hierarchical collapse (GHC). GHC
constitutes a flow regime of (non-homologous) collapses within collapses, in which all …

We measure the low-J CO line ratios R 21≡ CO (2–1)/CO (1–0), R 32≡ CO (3–2)/CO (2–1),
and R 31≡ CO (3–2)/CO (1–0) using whole-disk CO maps of nearby galaxies. We draw CO …

Giant molecular clouds (GMCs) are the sites of star formation and stellar feedback in
galaxies. Their properties set the initial conditions for star formation and their lifecycles …

We address the problem of the origin of massive stars, namely the origin, path, and
timescale of the mass flows that create them. Based on extensive numerical simulations, we …

We introduce a new suite of simulations,'The Cloud Factory', which self-consistently forms
molecular cloud complexes at high enough resolution to resolve internal substructure (up to …

Quenched galaxies are often observed to contain a strong bulge component. The key
question is whether this reflects a causal connection–can star formation be quenched …