The Star Formation Rate and Dense Molecular Gas in Galaxies

Gao, Yu; Solomon, P. M.

doi:10.1086/382999

Cited by 962 publications

(1,679 citation statements)

References 102 publications

Supporting

199

Mentioning

1,458

Contrasting

Unclassified

Order By: Relevance

“…This is apparent in the left panel of Figure 44, where the light orange circles represent local quiescent galaxies, and the light (small) blue stars represent local starbursts. Gao & Solomon (2004b) find a slope of 1.25 − 1.44 between L IR and L CO (i.e. pure observables) when considering unresolved CO (J=1-0) observations of both local quiescent galaxies, and nearby LIRGs and ULIRGs.…”

Section: Star Formation Laws and Efficienciesmentioning

confidence: 90%

Dusty star-forming galaxies at high redshift

2014

View full text Add to dashboard Cite

Far-infrared and submillimeter wavelength surveys have now established the important role of dusty, star-forming galaxies (DSFGs) in the assembly of stellar mass and the evolution of massive galaxies in the Universe. The brightest of these galaxies have infrared luminosities in excess of 10 13 L with implied star-formation rates of thousands of solar masses per year. They represent the most intense starbursts in the Universe, yet many are completely optically obscured. Their easy detection at submm wavelengths is due to dust heated by ultraviolet radiation of newly forming stars. When summed up, all of the dusty, star-forming galaxies in the Universe produce an infrared radiation field that has an equal energy density as the direct starlight emission from all galaxies visible at ultraviolet and optical wavelengths. The bulk of this infrared extragalactic background light emanates from galaxies as diverse as gas-rich disks to mergers of intense starbursting galaxies. Major advances in far-infrared instrumentation in recent years, both spacebased and ground-based, has led to the detection of nearly a million DSFGs, yet our understanding of the underlying astrophysics that govern the start and end of the dusty starburst phase is still in nascent stage. This review is aimed at summarizing the current status of DSFG studies, focusing especially on the detailed characterization of the bestunderstood subset (submillimeter galaxies, who were summarized in the last review of this field over a decade ago, Blain et al. 2002), but also the selection and characterization of more recently discovered DSFG populations. We review DSFG population statistics, their physical properties including dust, gas and stellar contents, their environments, and current theoretical models related to the formation and evolution of these galaxies.

show abstract

Section: Star Formation Laws and Efficienciesmentioning

confidence: 90%

Dusty star-forming galaxies at high redshift

2014

View full text Add to dashboard Cite

show abstract

“…There is good observational evidence (e.g., Kennicutt(1998), Gao & Solomon(2004), Greve et al (2005), Bouché et al (2007)) that at higher gas columns, the relation steepens further, so that the SFR-per-H 2 ratio is higher in starburst galaxies than in normal galaxy disks. This may drive the frequent observation of N ≈ 1.5 in starburst galaxies.…”

Section: The Composite Star Formation Lawmentioning

confidence: 99%

Scaling Relations between Gas and Star Formation in Nearby Galaxies

Bigiel¹,

Leroy

Walter

2010

Proc. IAU

View full text Add to dashboard Cite

Abstract. High resolution, multi-wavelength maps of a sizeable set of nearby galaxies have made it possible to study how the surface densities of H i, H2 and star formation rate (ΣHI,ΣH2 ,ΣSFR ) relate on scales of a few hundred parsecs. At these scales, individual galaxy disks are comfortably resolved, making it possible to assess gas-SFR relations with respect to environment within galaxies. Σ H 2 , traced by CO intensity, shows a strong correlation with ΣSFR and the ratio between these two quantities, the molecular gas depletion time, appears to be constant at about 2 Gyr in large spiral galaxies. Within the star-forming disks of galaxies, ΣSFR shows almost no correlation with ΣHI. In the outer parts of galaxies, however, ΣSFR does scale with ΣHI, though with large scatter. Combining data from these different environments yields a distribution with multiple regimes in Σgas − ΣSFR space. If the underlying assumptions to convert observables to physical quantities are matched, even combined datasets based on different SFR tracers, methodologies and spatial scales occupy a well define locus in Σgas − ΣSFR space.

show abstract

“…Incorrect gas masses could also introduce biases in the observed Schmidt-Kennicutt relation (Schmidt 1959;Kennicutt 1989), an empirical correlation thatprobes the physical process responsible for star formation (e.g., Bigiel et al 2008 and references therein) and is frequently used as input for numerical simulations of galaxy formation (e.g., Springel & Hernquist 2003;Narayanan et al 2008a;Somerville et al 2008;Juneau et al 2009). Despite numerous studies of the Schmidt-Kennicutt relation, differences in methods (integrated versus spatially resolved studies; e.g., Young et al 1986;Solomon & Sage 1988;Buat et al 1989;Kennicutt 1998Kennicutt , 1989Gao & Solomon 2004;Bouché et al 2007;Bigiel et al 2008;Krumholz et al 2009;Bigiel et al 2010;Daddi et al 2010;Genzel et al 2010;Wei et al 2010;Tacconi et al 2013), assumptions (particularly gas mass conversion factors; e.g., Bigiel et al 2008;Daddi et al 2010;Genzel et al 2010), gas and SFR tracers (e.g., Gao & Solomon 2004;Narayanan et al 2005;Bussmann et al 2008;Graciá-Carpio et al 2008;Iono et al 2009;Juneau et al 2009;Kennicutt & Evans 2012), and galaxy populations (e.g. Gao & Solomon 2004;Daddi et al 2010;Genzel et al 2010;Tacconi et al 2013) leadto significant uncertainties in the relation's characteristics (such as the index of the power law) and interpretation.…”

Section: Introductionmentioning

confidence: 99%

“…Despite numerous studies of the Schmidt-Kennicutt relation, differences in methods (integrated versus spatially resolved studies; e.g., Young et al 1986;Solomon & Sage 1988;Buat et al 1989;Kennicutt 1998Kennicutt , 1989Gao & Solomon 2004;Bouché et al 2007;Bigiel et al 2008;Krumholz et al 2009;Bigiel et al 2010;Daddi et al 2010;Genzel et al 2010;Wei et al 2010;Tacconi et al 2013), assumptions (particularly gas mass conversion factors; e.g., Bigiel et al 2008;Daddi et al 2010;Genzel et al 2010), gas and SFR tracers (e.g., Gao & Solomon 2004;Narayanan et al 2005;Bussmann et al 2008;Graciá-Carpio et al 2008;Iono et al 2009;Juneau et al 2009;Kennicutt & Evans 2012), and galaxy populations (e.g. Gao & Solomon 2004;Daddi et al 2010;Genzel et al 2010;Tacconi et al 2013) leadto significant uncertainties in the relation's characteristics (such as the index of the power law) and interpretation. Different molecular emission lines are sensitive to different density regimes in the ISM (Krumholz & Thompson 2007;Narayanan et al 2008bNarayanan et al , 2011, making the observed index of the Schmidt-Kennicutt relation dependent on the gas physical conditions.…”

Section: Introductionmentioning

confidence: 99%

A Total Molecular Gas Mass Census in Z ∼ 2–3 Star-Forming Galaxies: Low-J Co Excitation Probes of Galaxies’ Evolutionary States

Sharon

Riechers

Hodge

et al. 2016

ApJ

133

View full text Add to dashboard Cite

We present CO(1-0) observations obtained at the Karl G. Jansky Very Large Array for 14z 2 galaxies with existing CO(3-2) measurements, including 11 galaxies thatcontain active galactic nuclei (AGNs) and three submillimeter galaxies (SMGs). We combine this sample with an additional 15z 2 galaxies from the literature that have both CO(1-0) and CO(3-2) measurements in order to evaluate differences in CO excitation between SMGs and AGN host galaxies, tomeasure the effects of CO excitation on the derived molecular gas properties of these populations, and to look for correlations between the molecular gas excitation and other physical parameters. With our expanded sample of CO(3-2)/CO(1-0) line ratio measurements, we do not find a statistically significant difference in the mean line ratio between SMGs and AGN host galaxies as can be found in the literature; we instead find =  r 1.03 0. for both populations combined). We also do not measure a statistically significant difference between the distributions of the line ratios for these populations at the p=0.05 level, although this result is less robust. We find no excitation dependence on the index or offset of the integrated Schmidt-Kennicutt relation for the two CO lines, and weobtain indices consistent with N=1 for the various subpopulations. However, including low-z "normal" galaxies increases our best-fit Schmidt-Kennicutt index toÑ 1.2. While we do not reproduce correlations between the CO line width and luminosity, we do reproduce correlations between CO excitation and star-formation efficiency.

show abstract

The Star Formation Rate and Dense Molecular Gas in Galaxies

Cited by 962 publications

References 102 publications

Dusty star-forming galaxies at high redshift

Dusty star-forming galaxies at high redshift

Scaling Relations between Gas and Star Formation in Nearby Galaxies

A Total Molecular Gas Mass Census in Z ∼ 2–3 Star-Forming Galaxies: Low-J Co Excitation Probes of Galaxies’ Evolutionary States

Contact Info

Product

Resources

About