ALMA reveals starburst-like interstellar medium conditions in a compact star-forming galaxy at z ~ 2 using [CI] and CO

Abstract

We present ALMA detections of the [CI] 1-0, CO J=3-2, and CO J=4-3 emission lines, as well as the ALMA band 4 continuum for a compact star-forming galaxy (cSFG) at z=2.225, 3D-HST GS30274. As is typical for cSFGs, this galaxy has a stellar mass of $1.89\pm 0.47\times 10^{11}{\mathrm{M}}_{\odot }$, with a star formation rate of $214\pm 44{\mathrm{M}}_{\odot }{\mathrm{yr}}^{-1}$ putting it on the star-forming `main-sequence', but with an H-band effective radius of 2.5 kpc, making it much smaller than the bulk of `main-sequence' star-forming galaxies. The intensity ratio of the line detections yield an ISM density (~ 6 $\times 10^4{\mathrm{cm}}^{-3}$) and a UV-radiation field ( ~2 $\times 10^4{\mathrm{G}}_0$), similar to the values in local starburst and ultra-luminous infrared galaxy environments. A starburst phase is consistent with the short depletion times ($t_{H2,\mathrm{dep}}\le 140$ Myr) we find using three different proxies for the H2 mass ([CI], CO, dust mass). This depletion time is significantly shorter than in more extended SFGs with similar stellar masses and SFRs. Moreover, the gas fraction of 3D-HST GS30274 is smaller than typically found in extended galaxies. We measure the CO and [CI] kinematics and find a FWHM line width of ~$750\pm 41$ km s${}^{-1}$. The CO and [CI] FWHM are consistent with a previously measured H$\alpha$ FWHM for this source. The line widths are consistent with gravitational motions, suggesting we are seeing a compact molecular gas reservoir. A previous merger event, as suggested by the asymmetric light profile, may be responsible for the compact distribution of gas and has triggered a central starburst event. This event gives rise to the starburst-like ISM properties and short depletion times. The centrally located and efficient star formation is quickly building up a dense core of stars, responsible for the compact distribution of stellar light in 3D-HST GS30274.

Accepted for publication in A&A

References in corpus (33)

• Star Formation in AEGIS Field Galaxies since z=1.1 : The Dominance of Gradually Declining Star Formation, and the Main Sequence of Star-Forming Galaxies
• 3D-HST+CANDELS: The Evolution of the Galaxy Size-Mass Distribution since $z=3$
• A simple model to interpret the ultraviolet, optical and infrared emission from galaxies
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Constraining the Low-Mass Slope of the Star Formation Sequence at 0.5<z<2.5
• Combined CO & Dust Scaling Relations of Depletion Time and Molecular Gas Fractions with Cosmic Time, Specific Star Formation Rate and Stellar Mass
• Compaction and Quenching of High-z Galaxies in Cosmological Simulations: Blue and Red Nuggets
• The Chandra Deep Field-South Survey: 7 Ms Source Catalogs
• An ALMA survey of Sub-millimeter Galaxies in the Extended Chandra Deep Field South: Physical properties derived from ultraviolet-to-radio modelling
• Structure and star formation in galaxies out to z=3: evidence for surface density dependent evolution and upsizing
• Diagnostics of irradiated dense gas in galaxy nuclei. II. A grid of XDR and PDR models
• Evolution of the dust emission of massive galaxies up to z=4 and constraints on their dominant mode of star formation
• CO excitation of normal star forming galaxies out to z=1.5 as regulated by the properties of their interstellar medium
• The Formation of Massive, Compact Galaxies at z=2 in the Illustris Simulation
• Evidence for Wide-Spread AGN Driven Outflows in the Most Massive z~1-2 Star Forming Galaxies
• Vigorous star formation with low efficiency in massive disk galaxies at z=1.5
• Sub-kpc ALMA imaging of compact star-forming galaxies at z~2.5: revealing the formation of dense galactic cores in the progenitors of compact quiescent galaxies
• Effective destruction of CO by cosmic rays: implications for tracing H${}_2$ gas in the Universe
• Dense cores in galaxies out to z=2.5 in SDSS, UltraVISTA, and the five 3D-HST/CANDELS fields
• ALMA observations of atomic carbon in z~4 dusty star-forming galaxies
• Bulge-forming galaxies with an extended rotating disk at z~2
• ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Molecular gas reservoirs in high-redshift galaxies
• ALMA Imaging of HCN, CS and dust in Arp 220 and NGC 6240
• A Massive Galaxy in its Core Formation Phase Three Billion Years After the Big Bang
• Keck-I MOSFIRE spectroscopy of compact star-forming galaxies at z$\gtrsim$2: High velocity dispersions in progenitors of compact quiescent galaxies
• Evolution of the atomic and molecular gas content of galaxies in dark matter haloes
• The Origin of Line Emission in Massive z~2.3 Galaxies: Evidence for Cosmic Downsizing of AGN Host Galaxies
• Neutral carbon and CO in 76 (U)LIRGs and starburst galaxy centers A method to determine molecular gas properties in luminous galaxies
• Spectroscopic Confirmation of an Ultra Massive and Compact Galaxy at z=3.35: A Detailed Look at an Early Progenitor of Local Most Massive Ellipticals
• Low Gas Fractions Connect Compact Star-Forming Galaxies to their z ~ 2 Quiescent Descendants
• High-resolution HNC 3-2 SMA observations of Arp220
• Atomic Carbon in APM 08279+5255 at z=3.91
• Tracing high density gas in M 82 and NGC 4038

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