The sizes of $z\sim 6-8$ lensed galaxies from the Hubble Frontier Fields Abell 2744 data

Abstract

We investigate sizes of $z\sim 6-8$ dropout galaxies using the complete data of the Abell 2744 cluster and parallel fields in the Hubble Frontier Fields program. By directly fitting light profiles of observed galaxies with lensing-distorted Sérsic profiles on the image plane with the \texttt{glafic} software, we accurately measure intrinsic sizes of 31 $z\sim 6-7$ and eight $z\sim 8$ galaxies, including those as faint as $M_{\mathrm{UV}}\simeq -16.6$. We find that half-light radii $r_{\mathrm{e}}$ positively correlates with UV luminosity at each redshift, although the correlation is not very tight. Largest ($r_{\mathrm{e}}>0.8$ kpc) galaxies are mostly red in UV color while smallest ($r_{\mathrm{e}}<0.08$ kpc) ones tend to be blue. We also find that galaxies with multiple cores tend to be brighter. Combined with previous results at $2.5\lesssim z\lesssim 12$, our result confirms that the average $r_{\mathrm{e}}$ of bright ($(0.3-1)L_{z=3}^{\star }$) galaxies scales as $r_{\mathrm{e}}\propto (1+z{)}^{-m}$ with $m=1.24\pm 0.1$. We find that the ratio of $r_{\mathrm{e}}$ to virial radius is virtually constant at $3.3\pm 0.1\%$ over a wide redshift range, where the virial radii of hosting dark matter halos are derived based on the abundance matching. This constant ratio is consistent with the disk formation model by Mo et al. (1998) with $j_{\mathrm{d}}\sim m_{\mathrm{d}}$, where $j_{\mathrm{d}}$ and $m_{\mathrm{d}}$ are the fractions of the angular momentum and mass within halos confined in the disks. A comparison with various types of local galaxies indicates that our galaxies are most similar to circumnuclear star-forming regions of barred galaxies in the sense that a sizable amount of stars are forming in a very small area.

17 pages, 14 figures. Accepted for publication in ApJ

References in corpus (6)

• The Hubble Ultra Deep Field
• Galaxy Merger Morphologies and Time-Scales from Simulations of Equal-Mass Gas-Rich Disc Mergers
• Hubble Frontier Fields First Complete Cluster Data: Faint Galaxies at $z\sim 5-10$ for UV Luminosity Functions and Cosmic Reionization
• The Morphological Diversities Among Star-forming Galaxies at High Redshifts in the Great Observatories Origins Deep Survey (GOODS)
• Accounting for Cosmic Variance in Studies of Gravitationally-Lensed High-Redshift Galaxies in the Hubble Frontier Field Clusters
• Angular momentum and clustering properties of early dark matter halos

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