Star formation at the smallest scales; A JWST study of the clump populations in SMACS0723

Abstract

We present the clump populations detected in 18 lensed galaxies at redshifts 1 to 8.5 within the lensing cluster field SMACS0723. The recent JWST Early Release Observations of this poorly known region of the sky have revealed numerous point-like sources within and surrounding their host galaxies, undetected in the shallower HST images. We use JWST multiband photometry and the lensing model of this galaxy cluster to estimate the intrinsic sizes and magnitudes of the stellar clumps. We derive optical restframe effective radii from $<$10 to 100s pc and masses ranging from $\sim 10^5$ to $10^9$ M${}_{\odot }$, overlapping with massive star clusters in the local universe. The ages range from 1 Myr to 1 Gyr. We compare the crossing time to the age of the clumps and determine that between 45 and 60 % of the detected clumps are consistent with being gravitationally bound. The lack of Gyr old clumps suggest that the dissolution time scales are shorter than 1 Gyr. We see a significant increase in the luminosity (mass) surface density of the clumps with redshift. Clumps in galaxies at the reionisation era have stellar densities higher than massive clusters in the local universe. We zoom-in into single galaxies at redshift $<6$ and find for two galaxies, the Sparkler and the Firework, that their star clusters/clumps show distinctive colour distributions and location surrounding their host galaxy that are compatible with being accredited or formed during merger events. The ages of some of the compact clusters are between 1 and 4 Gyr, e.g., globular cluster precursors formed around 9-12 Gyr ago. Our study, conducted on a small sample of galaxies, shows the potential of JWST observations for understanding the conditions under which star clusters form in rapidly evolving galaxies.

Final version accepted for publication in MNRAS. Clump photometric table included in the appendix (available as online material only in main journal)

References in corpus (39)

• A Bayesian approach to strong lensing modelling of galaxy clusters
• The Resolved Properties of Extragalactic Giant Molecular Clouds
• Rapid formation of exponential disks and bulges at high redshift from the dynamical evolution of clump cluster and chain galaxies
• Bulge Formation by the Coalescence of Giant Clumps in Primordial Disk Galaxies
• The JWST Early Release Observations
• Clumpy Galaxies in CANDELS. I. The Definition of UV Clumps and the Fraction of Clumpy Galaxies at 0.5<z<3
• Paving the way for the JWST: witnessing globular cluster formation at z>3
• First look with JWST spectroscopy: $z\sim 8$ galaxies resemble local analogues
• Resolved spectroscopy of gravitationally lensed galaxies: global dynamics and star-forming clumps on ~100pc scales
• The distinction between star clusters and associations
• Star clusters near and far; tracing star formation across cosmic time
• Truncation of galaxy dark matter halos in high density environments
• The nature of giant clumps in distant galaxies probed by the anatomy of the Cosmic Snake
• DYNAMO-HST Survey: Clumps in Nearby Massive Turbulent Disks and the Effects of Clump Clustering on Kiloparsec Scale Measurements of Clumps
• Molecular clouds in the Cosmic Snake normal star-forming galaxy 8 billion years ago
• High star cluster formation efficiency in the strongly lensed Sunburst Lyman-continuum galaxy at z=2.37
• Radii of Young Star Clusters in Nearby Galaxies
• Star Formation at z=2.481 in the Lensed Galaxy SDSS J1110+6459: Star Formation down to 30 parsec scales
• The Sparkler: Evolved High-Redshift Globular Clusters Captured by JWST
• Star cluster formation in the most extreme environments: Insights from the HiPEEC survey
• Formation histories of stars, clusters and globular clusters in the E-MOSAICS simulations
• On the stellar masses of giant clumps in distant star-forming galaxies
• An extremely young massive clump forming by gravitational collapse in a primordial galaxy
• Exploring the physical properties of lensed star-forming clumps at $2\lesssim z\lesssim 6$
• Early results from GLASS-JWST. VII: evidence for lensed, gravitationally bound proto-globular clusters at z=4 in the Hubble Frontier Field A2744
• Early Results From GLASS-JWST. XII: The Morphology of Galaxies at the Epoch of Reionization
• Rings and Bent Chain Galaxies in the GEMS and GOOD Fields
• Introducing EMP-Pathfinder: modelling the simultaneous formation and evolution of stellar clusters in their host galaxies
• The minimum metallicity of globular clusters and its physical origin -- implications for the galaxy mass-metallicity relation and observations of proto-globular clusters at high redshift
• Great Balls of FIRE I: The formation of star clusters across cosmic time in a Milky Way-mass galaxy
• Sub-parsec resolution cosmological simulations of star-forming clumps at high redshift with feedback of individual stars
• Star-forming clumps in the Lyman Alpha Reference Sample of galaxies -- I. Photometric analysis and clumpiness
• The role of gas fraction and feedback in the stability and evolution of galactic discs: implications for cosmological galaxy formation models
• Clump Survival and Migration in VDI Galaxies: an Analytic Model versus Simulations and Observations
• Multiply lensed star forming clumps in the A521-sys1 galaxy at redshift 1
• Metallicities and ages for star clusters and their surrounding fields in the Large Magellanic Cloud
• Haro 11 -- Untying the knots of the nuclear starburst
• The contribution of globular clusters to cosmic reionization
• Stellar feedback in a clumpy galaxy at $z\sim$ 3.4

Cited by in corpus (53)

• JWST/NIRCam Probes Young Star Clusters in the Reionization Era Sunrise Arc
• N-enhancement in GN-z11: First evidence for supermassive stars nucleosynthesis in proto-globular clusters-like conditions at high redshift ?
• Extreme N-emitters at high-redshift: signatures of supermassive stars and globular cluster or black hole formation in action?
• A Magnified Compact Galaxy at Redshift 9.51 with Strong Nebular Emission Lines
• The Science of the Einstein Telescope
• Spatially Resolved Properties of High Redshift Galaxies in the SMACS0723 JWST ERO Field
• JWST reveals a possible $z\sim 11$ galaxy merger in triply-lensed MACS0647$-$JD
• Insight into the Starburst Nature of Galaxy GN-z11 with JWST MIRI Spectroscopy
• Massive star cluster formation I. High star formation efficiency while resolving feedback of individual stars
• Formation of star clusters and enrichment by massive stars in simulations of low-metallicity galaxies with a fully sampled initial stellar mass function
• Anatomy of a z=6 Lyman-α emitter down to parsec scales: extreme UV slopes, metal-poor regions and possibly leaking star clusters
• Star Cluster Formation and Survival in the First Galaxies
• Fraction of Clumpy Star-Forming Galaxies at $0.5\le z\le 3$ in UVCANDELS: Dependence on Stellar Mass and Environment
• The Ages and Metallicities of the Globular Clusters in the Sparkler
• Extreme Ionizing Properties of Metal-Poor, Muv ~ -12 Star Complex in the first Gyr
• The COSMOS-Web ring: in-depth characterization of an Einstein ring lensing system at z~2
• PANORAMIC: Discovery of an Ultra-Massive Grand-Design Spiral Galaxy at $z\sim 5.2$
• Rapid formation of a very massive star >50000 $M_{\odot }$ and subsequently an IMBH from runaway collisions. Direct N-body and Monte Carlo simulations of dense star clusters
• Multiple stellar population mass loss in massive Galactic globular clusters
• Clumps as multiscale structures in cosmic noon galaxies
• From giant clumps to clouds IV: extreme star-forming clumps on top of universal cloud scaling relations in gas-rich galaxies
• Rubin Observatory LSST Stars Milky Way and Local Volume Star Clusters Roadmap
• Witnessing an extreme, highly efficient galaxy formation mode with resolved Ly$\alpha$ and LyC emission
• Variation of the low-mass end of the stellar initial mass function with redshift and metallicity
• The ALMA-ALPINE [CII] survey: sub-kpc morphology of 3 main-sequence galaxy systems at z~4.5 revealed by ALMA
• SIEGE IV: compact star clusters in cosmological simulations with high star formation efficiency and sub-parsec resolution
• Reconstructing the extended structure of multiple sources strongly lensed by the ultra-massive elliptical galaxy SDSS J0100+1818
• Exploring the Evolution of Massive Clumps in Simulations that Reproduce the Observed Milky Way α-element Abundance Bimodality
• Globular cluster ages and their relation to high-redshift stellar cluster formation times from different globular cluster models
• Initial sizes of star clusters: implications for cluster dissolution during galaxy evolution
• BUFFALO Wild Wings: A High Precision Free-Form Lens Model of MACSJ0416 with Constraints on Dark Matter from Substructure and Highly Magnified Arcs
• Unveiling the Cosmic Gems Arc at $z\sim 10$ with JWST NIRCam
• A two-phase model of galaxy formation: III. The formation of globular clusters
• Exotic Image Formation in Strong Gravitational Lensing by Clusters of Galaxies -- IV. Elliptical NFW Lenses and Hyperbolic Umbilics
• Duration and properties of the embedded phase of star formation in 37 nearby galaxies from PHANGS-JWST
• Through Thick and Thin: The Cosmic Evolution of Disk Scale Height
• Globular clusters as cosmic clocks: new cosmological hints from their integrated light
• Spatially resolved H$\alpha$ emission in B14-65666: compact starbursts, ionizing efficiency and gas kinematics in an advanced merger at the Epoch of Reionization
• Unveiling dust, molecular gas, and high star formation efficiency in extremely UV bright star-forming galaxies at $z\sim 2.1-3.6$
• Extended Enriched Gas in a Multi-Galaxy Merger at Redshift 6.7
• Search strategies for supermassive stars in young clusters and application to nearby galaxies
• COOL-LAMPS IV: A Sample of Bright Strongly-Lensed Galaxies at $3<z<4$
• The dynamical evolution of the stellar clumps in the Sparkler galaxy
• Low-redshift analogues of cosmic noon galaxies as laboratories for clumpy star formation
• Cosmic wallflowers: the circumgalactic origins of isolated ultra-compact star clusters at $z>7$
• Deciphering the Milky Way's star formation at cosmic noon with high proper-motion stars: A precursor to the merger-driven starburst
• Clumpiness of galaxies revealed in the near-infrared with COSMOS-Web
• Time to Sparkler. Accurate ages of lensed globular clusters at $z=1.4$ with JWST photometry
• Compact [OIII] emission-line regions ("Green Seeds") in $\mathrm{H}\alpha$ emitters at Cosmic Noon from JWST Observations
• Fusion of JWST data: Demonstrating practical feasibility
• Nowhere Left to Hide: Uncovering All of the Massive Young Embedded Star Clusters in the Antennae with JWST
• Massive Star Clusters in the Semi-Analytical Galaxy Formation Model L-Galaxies 2020
• (Re)solving the Complex Multiscale Morphology and V-shaped Spectral Energy Distribution of a Newly Discovered Strongly Lensed Little Red Dot in A383