The VMC Survey. XXIX. Turbulence-controlled Hierarchical Star Formation in the Small Magellanic Cloud

Sun, Ning-Chen; Grijs, Richard de; Cioni, M. R. L.; Rubele, Stefano; Subramanian, Smitha; Loon, Jacco Th. van; Bekki, Kenji; Bell, Cameron P. M.; Ivanov, V. D.; Marconi, M.; Muraveva, T.; Oliveira, J. M.; Ripepi, V.

doi:10.3847/1538-4357/aabc50

Cited by 34 publications

(48 citation statements)

References 111 publications

(140 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The hierarchical fractal structure of the interstellar medium (ISM) results in a power-law distribution of the ISM components from which we can measure the fractal dimension of the distribution (e.g., Elmegreen & Falgarone 1996;Roman-Duval et al 2010). Within this framework, young star clusters should inherit their clustered distribution from the ISM structure from which they are born; observations corroborate the hierarchy of gas (e.g., Elmegreen & Falgarone 1996;Stutzki et al 1998;Sánchez et al 2010;Miville-Deschênes et al 2010;Elia et al 2018) as well as protostellar cores (Johnstone et al 2000(Johnstone et al , 2001Enoch et al 2006;Stanke et al 2006;Young et al 2006) and young stellar objects (Bressert et al 2010;Sun et al 2018).…”

Section: Introductionmentioning

confidence: 91%

The spatial relation between young star clusters and molecular clouds in M51 with LEGUS

Grasha

Calzetti

Adamo

et al. 2018

Monthly Notices of the Royal Astronomical Society

107

105

View full text Add to dashboard Cite

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 ∼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 α = −0.28 ± 0.04, than the GMCs (α = −0.09 ± 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 (α = −0.35 ± 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.

show abstract

Section: Introductionmentioning

confidence: 91%

The spatial relation between young star clusters and molecular clouds in M51 with LEGUS

Grasha

Calzetti

Adamo

et al. 2018

Monthly Notices of the Royal Astronomical Society

107

105

View full text Add to dashboard Cite

show abstract

“…In the present work, instead, we aim at deriving the SFH, following a method which requires the data being grouped into spatial bins. These spatial bins are certainly larger than the resolution adopted by Sun et al (2018), but still small enough to allow us to discuss, in a quantitative way, the spatial distribution of the populations of all ages. Therefore, both works provide complementary (and overall consistent) views of the SMC stellar populations, at different spatial scales and age ranges.…”

Section: Introductionmentioning

confidence: 99%

“…Furthermore, the derived SFH, extinction and distance values are at the basis of other population and stellar evolution work being carried out with the aid of additional SMC data (Pastorelli et al, in prep.). Finally, we note that Sun et al (2018) analyse the SMC's young star formation, using essentially the same data but very different methods. That paper uses the detailed spatial resolution available in VMC data to identify young stellar structures and characterize their size and mass distributions.…”

Section: Introductionmentioning

confidence: 99%

The VMC survey – XXXI: The spatially resolved star formation history of the main body of the Small Magellanic Cloud

Rubele

Pastorelli

Girardi

et al. 2018

Monthly Notices of the Royal Astronomical Society

Self Cite

122

View full text Add to dashboard Cite

We recover the spatially resolved star formation history across the entire main body and Wing of the Small Magellanic Cloud (SMC), using fourteen deep tile images from the VISTA survey of the Magellanic Clouds (VMC), in the Y JK s filters. The analysis is performed on 168 subregions of size 0.143 deg 2 , covering a total contiguous area of 23.57 deg 2 . We apply a colour-magnitude diagram (CMD) reconstruction method that returns the best-fitting star formation rate SFR(t), age-metallicity relation, distance and mean reddening, together with their confidence intervals, for each subregion. With respect to previous analyses, we use a far larger set of VMC data, updated stellar models, and fit the two available CMDs (Y −K s versus K s and J −K s versus K s ) independently. The results allow us to derive a more complete and more reliable picture of how the mean distances, extinction values, star formation rate, and metallicities vary across the SMC, and provide a better description of the populations that form its Bar and Wing. We conclude that the SMC has formed a total mass of (5.31 ± 0.05) × 10 8 M in stars over its lifetime. About two thirds of this mass is expected to be still locked in stars and stellar remnants. 50 per cent of the mass was formed prior to an age of 6.3 Gyr, and 80 per cent was formed between 8 and 3.5 Gyr ago. We also illustrate the likely distribution of stellar ages and metallicities in different parts of the CMD, to aid the interpretation of data from future astrometric and spectroscopic surveys of the SMC.

show abstract

“…The mostly self-similar appearance of the interstellar medium (ISM), especially at scales L 1 pc is generally thought E-mail: davide.elia@iaps.inaf.it to be the result of turbulence (Elmegreen 1995;Elmegreen & Scalo 2004;Dib & Burkert 2005;Krumholz 2014), because of the intrinsic self-similarity of this phenomenon, triggered by the very high value of the Reynolds number in these environments. The fractal geometry is largely invoked to provide a quantitative characterization of the ISM morphology, as it can be deduced from far-infrared (FIR) or sub-millimetre maps, through fractal descriptors (Stutzki et al 1998;Bensch et al 2001;Schneider et al 2011;Sun et al 2018;Elia et al 2014, hereafter Paper I) and comparing these quantities with theoretical expectations has two important advantages. On the one hand, a comparison between models and observations gives indications about the kind of turbulence that is prevalent in the observed cloud and, on the other hand, the obtained fractal parameters can be used as further constraints for future simulations.…”

Section: Introductionmentioning

confidence: 99%

Multifractal analysis of the interstellar medium: first application to Hi-GAL observations

Elia

Strafella

Dib

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

The multifractal geometry remains an under-exploited approach to describe and quantify the large-scale structure of interstellar clouds. In this paper, the typical tools of multifractal analysis are applied to Herschel far-infrared (70-500 µm) dust continuum maps, which represent an ideal case of study. This dust component is a relatively optically thin tracer at these wavelengths and the size in pixel of the maps is well suitable for this statistical analysis. We investigate the so-called multifractal spectrum and generalised fractal dimension of six Hi-GAL regions in the third Galactic quadrant. We measure systematic variations of the spectrum at increasing wavelength, which generally correspond to an increasing complexity of the image, and we observe peculiar behaviours of the investigated fields, strictly related to the presence of highemission regions, which in turn are connected to star formation activity. The same analysis is applied to synthetic column density maps, generated from numerical turbulent molecular cloud models and from fractal Brownian motion (fBm), allowing for the confrontation of the observations with models with well controlled physical parameters. This comparison shows that, in terms of multifractal descriptors of the structure, fBm images exhibit a very different, quite unrealistic behaviour when compared with Hi-GAL observations, whereas the numerical simulations appear in some cases (depending on the specific model) more similar to the observations. Finally, the link between mono-fractal parameters (commonly found in the literature) and multifractal indicators is investigated: the former appear to be only partially connected with the latter, with the multifractal analysis offering a more extended and complete characterization of the cloud structure.

show abstract

The VMC Survey. XXIX. Turbulence-controlled Hierarchical Star Formation in the Small Magellanic Cloud

Cited by 34 publications

References 111 publications

The spatial relation between young star clusters and molecular clouds in M51 with LEGUS

The spatial relation between young star clusters and molecular clouds in M51 with LEGUS

The VMC survey – XXXI: The spatially resolved star formation history of the main body of the Small Magellanic Cloud

Multifractal analysis of the interstellar medium: first application to Hi-GAL observations

Contact Info

Product

Resources

About