Kiloparsec-scale Imaging of the CO(1-0)-traced Cold Molecular Gas Reservoir in a z ∼ 3.4 Submillimeter Galaxy

Castillo, Marta Frias; Rybak, Matus; Hodge, J. A.; Werf, P. P. van der; Riechers, Dominik A.; Vieira, Daniel; Rivera, G. Calistro; Martínez-Ramírez, Laura N.; Walter, Fabian; Blok, W. J. G. de; Narayanan, Desika; Wagg, Jeff

doi:10.3847/1538-4357/ac6105

Cited by 7 publications

(12 citation statements)

References 99 publications

(140 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our value for r 31 is higher than the ratio found by Ivison et al (2011), 0.55 ± 0.05, for SMGs at z = 2.2-2.5, and consistent with 0.63 ± 0.12 from Birkin et al (2021). There are fewer data points available on r 41 : our r 41 = 0.63 ± 0.11 is consistent with r 41 = 0.56 ± 0.20 and 0.45 ± 0.12, found, respectively, for the unlensed SMGs J13120+4242 and GN20 (Carilli et al 2010;Frias Castillo et al 2022).…”

Section: Co Spectral Line Energy Distributions and Line Ratiossupporting

confidence: 83%

“…It is common to assume an ULIRG-like value of α CO ∼ 1 for starburst systems at high redshift, such as our SMGs. However, recent studies based on dynamical modeling point toward a value of α CO = 1-2 (Danielson et al 2011;Rivera et al 2018;Birkin et al 2021;Frias Castillo et al 2022). Assuming α CO = 1, we find a median M mol = (1.4 ± 0.3) × 10 11 M e .…”

Section: Gas Masses Gas Fractions and Depletion Timesmentioning

confidence: 48%

“…Previous studies have suggested that some highredshift SMGs have line widths in CO(1-0) that are larger than those of the higher-J CO transitions (Ivison et al 2010;Riechers et al 2011b). Together with the fact that radiative transfer models underpredict the observed low-J CO emission, this suggests the presence of extended, low-excitation gas reservoirs in some SMGs (although not all, e.g., Hodge et al 2012;Frias Castillo et al 2022). We find that the widths of the lines agree with their mid-J counterparts within 2σ, with a median ratio FWHM CO(1−0) /FWHM -CO Jup,Jup 1 ( ) = 1.1 ± 0.1.…”

Section: Line Detectionsmentioning

confidence: 97%

“…Our knowledge of the cold molecular gas content in nonlensed systems comes from targeted studies (Carilli et al 2010;Riechers et al 2011bRiechers et al , 2011aIvison et al 2011;Sharon et al 2016;Huynh et al 2017;Kaasinen et al 2019;Leung et al 2019;Frias Castillo et al 2022;Xiao et al 2022). While valuable, carrying out a systematic study of a statistically significant sample of CO(1-0) emission of high-redshift galaxies has been hampered by the rather heterogeneous selection criteria applied in the different studies.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

VLA Legacy Survey of Molecular Gas in Massive Star-forming Galaxies at High Redshift

Castillo

Hodge

Rybak

et al. 2023

ApJ

Self Cite

View full text Add to dashboard Cite

We present the initial results of an ongoing survey with the Karl G. Jansky Very Large Array targeting the CO(J = 1–0) transition in a sample of 30 submillimeter-selected, dusty star-forming galaxies (SFGs) at z = 2–5 with existing mid-J CO detections from the Atacama Large Millimeter/submillimeter Array and NOrthern Extended Millimeter Array, of which 17 have been fully observed. We detect CO(1–0) emission in 11 targets, along with three tentative (∼1.5σ–2σ) detections; three galaxies are undetected. Our results yield total molecular gas masses of 6–23 × 1010 (α CO/1) M ⊙, with gas mass fractions, f gas = M mol/(M *+M mol), of 0.1–0.8 and a median depletion time of (140 ± 70) Myr. We find median CO excitation ratios of r 31 = 0.75 ± 0.39 and r 41 = 0.63 ± 0.44, with significant scatter. We find no significant correlation between the excitation ratio and a number of key parameters such as redshift, CO(1–0) line width, or ΣSFR. We only find a tentative positive correlation between r 41 and the star-forming efficiency, but we are limited by our small sample size. Finally, we compare our results to predictions from the SHARK semi-analytical model, finding a good agreement between the molecular gas masses, depletion times, and gas fractions of our sources and their SHARK counterparts. Our results highlight the heterogeneous nature of the most massive SFGs at high redshift, and the importance of CO(1–0) observations to robustly constrain their total molecular gas content and interstellar medium properties.

show abstract

Section: Co Spectral Line Energy Distributions and Line Ratiossupporting

confidence: 83%

Section: Gas Masses Gas Fractions and Depletion Timesmentioning

confidence: 48%

Section: Line Detectionsmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

VLA Legacy Survey of Molecular Gas in Massive Star-forming Galaxies at High Redshift

Castillo

Hodge

Rybak

et al. 2023

ApJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…Riechers et al 2011a;Calistro Rivera et al 2018) and [C ii] emission (e.g. Gullberg et al 2018;Rybak et al 2019Rybak et al , 2020, even in galaxies with narrow linewidth (Frias Castillo et al 2022). For example, SDP.81 has a compact FIR-bright starburst (∼2 kpc across) embedded in a 15-kpc CO(1-0) and [C ii] reservoir (Rybak et al 2015b(Rybak et al , 2020.…”

Section: Co and Hcn Star-formation Efficienciesmentioning

confidence: 99%

Prussic

Rybak

Hodge

Greve

et al. 2022

A&A

View full text Add to dashboard Cite

Dusty star-forming galaxies (DSFGs) at redshift z ≥ 1 are among the most vigorously star-forming galaxies in the Universe. However, their dense (≥ 10 5 cm −3 ) gas phase -typically traced by HCN(1-0) -remains almost entirely unexplored: only two DSFGs have been detected in HCN(1-0) to date. We present results of a JVLA survey of the J=1-0 transition of HCN, HCO + , and HNC(1-0) in six strongly lensed DSFGs at z = 2.5 − 3.3, effectively doubling the number of DSFGs with deep observations of these lines. We detect HCN(1-0) emission in one source (J1202+5354, 4.4σ), with a tentative HCO + (1-0) detection in another (J1609+6045, 3.3σ). Spectral stacking yields strict upper limits on the HCN/FIR (≤ 3.6 × 10 −4 ) and HCN/CO(1-0) ratios (≤0.045). The inferred HCN/FIR ratios (a proxy for the star-formation efficiency) are consistent with those in z ∼ 0 FIR-luminous starbursts. However, the HCN/CO ratios -a proxy for the dense-gas fraction -are a factor of a few lower than suggested by the two previous DSFG detections. Our results imply that most DSFGs have low dense-gas fractions. A comparison with Krumholz & Thompson (2007) models of star-forming galaxies indicates that the bulk of gas in DSFGs is at lower densities (≈10 2 cm −3 ), similar to "normal" star-forming galaxies, rather than ultraluminous starbursts.

show abstract

ALMA-ALPINE [CII] survey: The sub-kpc morphology of three main sequence galaxy systems at z ∼ 4.5 revealed by ALMA

Devereaux,

Cassata,

Ibar

et al. 2024

A&A

View full text Add to dashboard Cite

Going from a redshift of 6 down to nearly 4, galaxies grow rapidly from low-mass galaxies towards the more mature types of massive galaxies seen at cosmic noon. Growth via gas accretion and mergers undoubtedly shape this evolution, however, there is considerable uncertainty at present over the contribution of each of these processes to the overall evolution of galaxies. Furthermore, previous characterisations of the morphology of galaxies in the molecular gas phase have been limited by the coarse resolution of earlier observations. In this work, we utilise new high-resolution ALMA CII observations to analyse three main sequence (MS) galaxy systems at a redshift of $z and at resolutions of up to $0.15''$. This approach enables us to investigate the morphology and kinematics on a kpc scale and understand the processes at play as well as the classifications of galaxies at high resolution. Thanks to this unique window, we are able to gain insights into the molecular gas of MS galaxies undergoing mass assembly in the early Universe We used intensity and velocity maps, position-velocity diagrams, and radial profiles of CII in combination with dust continuum maps to analyse the morphology and kinematics of the three systems. In general, we find that the high-resolution ALMA data reveal more complex morpho-kinematic properties. For one galaxy in our sample, we identified interaction-induced clumps, demonstrating the profound effect that mergers have on the molecular gas in galaxies, which is consistent with what has been suggested by recent simulations. One galaxy that was previously classified as dispersion-dominated turned out to show two bright CII emission regions, which could either be classified as merging galaxies or massive star-forming regions within the galaxy itself. The high-resolution data for the other dispersion dominated object also revealed clumps of CII that had not been identified previously. Within the sample, we might also detect star-formation powered outflows (or outflows from active galactic nuclei) that appear to be fuelling diffuse gas regions and enriching the circumgalactic medium. The new high-resolution ALMA data we present in this paper reveal that the galaxies in our sample are much more complex than they previously appeared in the low-resolution ALPINE data. In particular, we find evidence of merger induced clumps in the galaxy DC8187, along with signs of merging components for the other two objects. This may be evidence that the number of mergers at high redshift are significantly underestimated at present.

show abstract

Kiloparsec-scale Imaging of the CO(1-0)-traced Cold Molecular Gas Reservoir in a z ∼ 3.4 Submillimeter Galaxy

Cited by 7 publications

References 99 publications

VLA Legacy Survey of Molecular Gas in Massive Star-forming Galaxies at High Redshift

VLA Legacy Survey of Molecular Gas in Massive Star-forming Galaxies at High Redshift

Prussic

ALMA-ALPINE [CII] survey: The sub-kpc morphology of three main sequence galaxy systems at z ∼ 4.5 revealed by ALMA

Contact Info

Product

Resources

About