The Spatial Relation between Young Star Clusters and Molecular Clouds in M 51 with LEGUS

Abstract

We present a study correlating the spatial locations of young star clusters with those of molecular clouds in NGC~5194, in order to investigate the timescale over which clusters separate from their birth clouds. The star cluster catalogues are from the Legacy ExtraGalactic UV Survey (LEGUS) and the molecular clouds from the Plateau de Bure Interefrometer Arcsecond Whirpool Survey (PAWS). We find that younger star clusters are spatially closer to molecular clouds than older star clusters. The median ages for clusters associated with clouds is 4~Myr whereas it is 50~Myr for clusters that are sufficiently separated from a molecular cloud to be considered unassociated. After $\sim$6~Myr, the majority of the star clusters lose association with their molecular gas. Younger star clusters are also preferentially located in stellar spiral arms where they are hierarchically distributed in kpc-size regions for 50-100~Myr before dispersing. The youngest star clusters are more strongly clustered, yielding a two-point correlation function with $\alpha =-0.28\pm 0.04$, than the GMCs ($\alpha =-0.09\pm 0.03$) within the same PAWS field. However, the clustering strength of the most massive GMCs, supposedly the progenitors of the young clusters for a star formation efficiency of a few percent, is comparable ($\alpha =-0.35\pm 0.05$) to that of the clusters. We find a galactocentric-dependence for the coherence of star formation, in which clusters located in the inner region of the galaxy reside in smaller star-forming complexes and display more homogeneous distributions than clusters further from the centre. This result suggests a correlation between the survival of a cluster complex and its environment.

17 pages, 12 figures. Accepted for publication in MNRAS

References in corpus (31)

• The NumPy array: a structure for efficient numerical computation
• The 2013 Release of Cloudy
• What is Driving the HI Velocity Dispersion?
• Bolocam Survey for 1.1 mm Dust Continuum Emission in the c2d Legacy Clouds. II. Ophiuchus
• Legacy ExtraGalactic UV Survey (LEGUS) with The Hubble Space Telescope. I. Survey Description
• The Fractal Density Structure in Supersonic Isothermal Turbulence: Solenoidal versus Compressive Energy Injection
• Variations in Stellar Clustering with Environment: Dispersed Star Formation and the Origin of Faint Fuzzies
• A complete 12CO 2-1 map of M51 with HERA: I. Radial averages of CO, HI, and radio continuum
• Studying the YMC population of M83: how long clusters remain embedded, their interaction with the ISM and implications for GC formation theories
• The dangers of being trigger--happy
• ALMA Observations of the Antennae Galaxies: I. A New Window on a Prototypical Merger
• On the Similarity between Cluster and Galactic Stellar Initial Mass Functions
• Short GMC lifetimes: an observational estimate with the PdBI Arcsecond Whirlpool Survey (PAWS)
• An alternative method to study star cluster disruption
• The spatial distribution of star and cluster formation in M51
• The Young Star Cluster population of M51 with LEGUS: I. A comprehensive study of cluster formation and evolution
• The PdBI Arcsecond Whirlpool Survey (PAWS). The Role of Spiral Arms in Cloud and Star Formation
• Hierarchical Star Formation in Nearby LEGUS Galaxies
• Hierarchical star formation in the Milky Way disk
• Hierarchical Star Formation in Turbulent Media: Evidence from Young Star Clusters
• The fractal dimension of star-forming regions at different spatial scales in M33
• CO-dark gas and molecular filaments in Milky Way-type galaxies - II: The temperature distribution of the gas
• Star-formation rates from young-star counts and the structure of the ISM across the NGC346/N66 complex in the SMC
• The Fractal Distribution of HII Regions in Disk Galaxies
• Kinematics and Structure of Star-forming Regions: Insights from Cold Collapse Models
• The VMC Survey XXII. Hierarchical Star Formation in the 30 Doradus-N158-N159-N160 Star-Forming Complex
• Star complexes and stellar populations in NGC 6822 - Comparison with the Magellanic Clouds
• The Correlation Dimension of Young Stars in Dwarf Galaxies
• The VMC Survey XXVII. Young Stellar Structures in the LMC${}^{\prime }$s Bar Star-Forming Complex
• The location, clustering, and propagation of massive star formation in giant molecular clouds
• Robust Cross-correlation-based Measurement of Clump Sizes in Galaxies

Cited by in corpus (6)

• The lifecycle of molecular clouds in nearby star-forming disc galaxies
• Star clusters near and far; tracing star formation across cosmic time
• Star cluster formation in the most extreme environments: Insights from the HiPEEC survey
• A Variant Stellar-to-nebular Dust Attenuation Ratio on Subgalactic and Galactic Scales
• Propagation of star formation at sub-kiloparsec scales
• Spatial segregation of massive clusters in dwarf galaxies