Slow Star Formation in the Milky Way: Theory Meets Observations

Abstract

The observed star formation rate of the Milky Way can be explained by applying a metallicity-dependent factor to convert CO luminosity to molecular gas mass and a star formation efficiency per free-fall time that depends on the virial parameter of a molecular cloud. These procedures also predict the trend of star formation rate surface density with Galactocentric radius. The efficiency per free-fall time variation with virial parameter plays the major role in bringing theory into agreement with observations for the total star formation rate, while the metallicity dependence of the CO luminosity to mass conversion is most notable in the variation with Galactocentric radius. Application of these changes resolves a factor of over 100 discrepancy between observed and theoretical star formation rates that has been known for nearly 50 years.

arXiv commentIn press, Astrophysical Journal Letters 11 pages, 6 figures

References in corpus (61)

• Astropy: A Community Python Package for Astronomy
• The NumPy array: a structure for efficient numerical computation
• Binary companions of evolved stars in APOGEE DR14: Search method and catalog of ~5,000 companions
• Star Formation in the Milky Way and Nearby Galaxies
• Theory of Star Formation
• The CO-to-H2 Conversion Factor
• The Milky Way in Molecular Clouds: A New Complete CO Survey
• A General Theory of Turbulence-Regulated Star Formation, From Spirals to ULIRGs
• A geometric distance measurement to the Galactic Center black hole with 0.3% uncertainty
• The Star Formation Rate of Turbulent Magnetized Clouds: Comparing Theory, Simulations, and Observations
• The chemical make-up of the Sun: A 2020 vision
• Star Clusters Across Cosmic Time
• Hi-GAL: the Herschel infrared Galactic Plane Survey
• Improved Estimates of the Milky Way's Stellar Mass and Star Formation Rate from Hierarchical Bayesian Meta-Analysis
• The mass function of dense molecular cores and the origin of the IMF
• The Star Formation Rate of Supersonic MHD Turbulence
• The Evolution of the Star-forming Interstellar Medium across Cosmic Time
• The WISE Catalog of Galactic HII Regions
• Physical properties of molecular clouds for the entire Milky Way disk
• Connecting Dense Gas Tracers of Star Formation in our Galaxy to High-z Star Formation
• Toward a Unification of Star Formation Rate Determinations in the Milky Way and Other Galaxies
• The Mass Distribution and Lifetime of Prestellar Cores in Perseus, Serpens, and Ophiuchus
• The Big Problems in Star Formation: the Star Formation Rate, Stellar Clustering, and the Initial Mass Function
• The relation between gas and dust in the Taurus Molecular Cloud
• Low CO Luminosities in Dwarf Galaxies
• Inefficient star formation through turbulence, magnetic fields and feedback
• Three-phase Interstellar medium in Galaxies Resolving Evolution with Star formation and Supernova feedback (TIGRESS): Algorithms, Fiducial model, and Convergence
• The Green Bank Telescope HII Region Discovery Survey II. The Source Catalog
• Evolutionary Signatures in the Formation of Low-Mass Protostars. II. Towards Reconciling Models and Observations
• Star formation rates and efficiencies in the Galactic Centre
• A Uniform Catalog of Molecular Clouds in the Milky Way
• Tracing the total molecular gas in galaxies: [CII] and the CO-dark gas
• A Simple Law of Star Formation
• Star Formation in Massive Clusters via the Wilkinson Microwave Anisotropy Probe and the Spitzer Glimpse Survey
• Observational Evidence of Dynamic Star Formation Rate in Milky Way Giant Molecular Clouds
• Molecular Gas Properties on Cloud Scales Across the Local Star-forming Galaxy Population
• The dynamics and outcome of star formation with jets, radiation, winds, and supernovae in concert
• Deriving a multivariate CO-to-H${}_2$ conversion function using the [CII]/CO(1-0) ratio and its application to molecular gas scaling relations
• EMPIRE: The IRAM 30-m Dense Gas Survey of Nearby Galaxies
• The Star Formation Efficiency per Free Fall Time in Nearby Galaxies
• Star Formation Efficiency and Dispersal of Giant Molecular Clouds with UV Radiation Feedback: Dependence on Gravitational Boundedness and Magnetic Fields
• Testing the universality of the star formation efficiency in dense molecular gas
• Star Formation Relations in the Milky Way
• The Galactic radial abundance gradients of C, N, O, Ne, S, Cl and Ar from deep spectra of H II regions
• Numerical Simulations of Turbulent, Molecular Clouds Regulated by Radiation Feedback Forces I: Star Formation Rate and Efficiency
• The environmental dependence of the X_CO conversion factor
• The Green Bank Telescope HII Region Discovery Survey: III. Kinematic Distances
• The Effects of Magnetic Fields and Protostellar Feedback on Low-mass Cluster Formation
• Metallicity Structure in the Milky Way Disk Revealed by Galactic HII Regions
• Gradients of chemical abundances in the Milky Way from HII regions: distances derived from Gaia EDR3 parallaxes and temperature inhomogeneities
• The star formation efficiency and its relation to variations in the initial mass function
• On the radial abundance gradients of nitrogen and oxygen in the inner Galactic disc
• The Mass-Size Relation and the Constancy of GMC Surface Densities in the Milky Way
• Numerical Calibration of the HCN$-$Star Formation Correlation
• Star Formation Occurs in Dense Gas, but What Does "Dense" Mean?
• The Giant Molecular Cloud Environments of Infrared Dark Clouds
• Milky Way metallicity gradient from Gaia DR2 F/1O double-mode Cepheids
• Rotation of molecular clouds in M~51
• Cloud Properties and Correlations with Star Formation in Numerical Simulations of the Three-Phase ISM
• An analysis of star formation with Herschel in the Hi-GAL Survey. II. The tips of the Galactic bar
• Spectroscopic Identification and Chemical Distribution of HII Regions in the Galactic Anti-center Area from LAMOST

Cited by in corpus (13)

• Pressure-Regulated, Feedback-Modulated Star Formation In Disk Galaxies
• Star Formation Laws and Efficiencies across 80 Nearby Galaxies
• The Star Formation Rate of the Milky Way as seen by Herschel
• Infrared Radiation Feedback Does Not Regulate Star Cluster Formation
• Characterizing the line emission from molecular clouds. II. A comparative study of California, Perseus, and Orion A
• On the Origin of the High Star-Formation Efficiency in Massive Galaxies at Cosmic Dawn
• First Detection of Radio Recombination Lines of Ions Heavier than Helium
• Gravitationally Bound Gas Determines Star Formation in the Galaxy
• Reconciling extragalactic star formation efficiencies with theory: insights from PHANGS
• Gravity or turbulence? VII. The Schmidt-Kennicutt law, the star formation efficiency, and the mass density of clusters from gravitational collapse rather than turbulent support
• On the Scarcity of Dense Cores ($n>10^5$ cm${}^{-3}$) in High Latitude Planck Galactic Cold Clumps
• The Hierarchical Dynamical State of Molecular Gas from 3 to 300 pc in NGC 253
• The Star Formation Factory revisited I. The impact of metallicity on collapsing star-forming clouds