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In the hierarchical view of star formation, giant molecular clouds (GMCs) undergo fragmentation to form small-scale structures made up of stars and star clusters. Here we study the connection between young star clusters and cold gas across a range of extragalactic environments by combining the high resolution (1″) PHANGS–ALMA catalogue of GMCs with the star cluster catalogues from PHANGS– HST. The star clusters are spatially matched with the GMCs across a sample of 11 nearby star-forming galaxies with a range of galactic environments (centres, bars, spiral arms, etc.). We find that after 4 − 6 Myr the star clusters are no longer associated with any gas clouds. Additionally, we measure the autocorrelation of the star clusters and GMCs as well as their cross-correlation to quantify the fractal nature of hierarchical star formation. Young (≤10 Myr) star clusters are more strongly autocorrelated on kpc and smaller spatial scales than the |$\gt \, 10$|  Myr stellar populations, indicating that the hierarchical structure dissolves over time. [ABSTRACT FROM AUTHOR]

Aims. Distances and radial velocities of galaxies in the vicinity of the luminous early-type galaxy M 104 (Sombrero) are used to derive its dark matter mass. Methods. Two dwarf galaxies: UGCA 307 and KKSG 30 situated near M 104 were observed with the Advanced Camera for Surveys on the Hubble Space Telescope. The distances 9.03−0.51+0.84 9. 03 − 0.51 + 0.84 $ 9.03^{+0.84}_{-0.51} $ Mpc (UGCA 307) and 9.72−0.41+0.44 9. 72 − 0.41 + 0.44 $ 9.72^{+0.44}_{-0.41} $ Mpc (KKSG 30) were determined using the tip of the red giant branch method. These distances are consistent with the dwarf galaxies being satellites of Sombrero. Results. Using radial velocities and projected separations of UGCA 307, KKSG 30, and a third galaxy with an accurate distance (KKSG 29), as well as 12 other assumed companions with less accurate distances, the total mass of M 104 is estimated to be (1.55 ± 0.49) × 1013 M⊙. At the K-band luminosity of the Sombrero galaxy of 2.4 × 1011 L⊙, its total mass-to-luminosity ratio is MT/LK = (65 ± 20) M⊙/L⊙, which is about three times higher than that of luminous bulgeless galaxies. [ABSTRACT FROM AUTHOR]