The systematically varying stellar IMF

Abstract

Some ultra-compact dwarf galaxies have large dynamical mass to light (M/L) ratios and also appear to contain an overabundance of LMXB sources, and some Milky Way globular clusters have a low concentration and appear to have a deficit of low-mass stars. These observations can be explained if the stellar IMF becomes increasingly top-heavy with decreasing metallicity and increasing gas density of the forming object. The thus constrained stellar IMF then accounts for the observed trend of metallicity and M/L ratio found amongst M31 globular star clusters. It also accounts for the overall shift of the observationally deduced galaxy-wide IMF from top-light to top-heavy with increasing star formation rate amongst galaxies. If the IMF varies similarly to deduced here, then extremely young very massive star-burst clusters observed at a high redshift would appear quasar-like (Jerabkova et al. 2017) .

arXiv commentAppearing in the proceedings of IAUS351 on Star Clusters: From the Milky Way to the Early Universe, held in Bologna, May 27th-31st

References in corpus (37)

• The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems
• A Universal Stellar Initial Mass Function? A Critical Look at Variations
• Comparison of H-alpha and UV Star Formation Rates in the Local Volume: Systematic Discrepancies for Dwarf Galaxies
• Early Star Formation and the Evolution of the Stellar Initial Mass Function in Galaxies
• An Extremely Top-Heavy IMF in the Galactic Center Stellar Disks
• The galaxy stellar mass-star formation rate relation: Evidence for an evolving stellar initial mass function?
• A Theory of the IMF for Star Formation in Molecular Clouds
• Evidence for top-heavy stellar initial mass functions with increasing density and decreasing metallicity
• Evidence for a Non-Uniform Initial Mass Function in the Local Universe
• An excess of massive stars in the local 30 Doradus starburst
• The stellar and sub-stellar IMF of simple and composite populations
• Stellar populations dominated by massive stars in dusty starburst galaxies across cosmic time
• Galaxy And Mass Assembly (GAMA): The star formation rate dependence of the stellar initial mass function
• A cosmic-ray dominated ISM in Ultra Luminous Infrared Galaxies: new initial conditions for star formation
• Evidence for a non-universal stellar initial mass function from the integrated properties of SDSS galaxies
• A top-heavy stellar initial mass function in starbursts as an explanation for the high mass-to-light ratios of ultra compact dwarf galaxies
• The Dawes Review 8: Measuring the Stellar Initial Mass Function
• The mmax-Mecl relation, the IMF and IGIMF: probabilistically sampled functions?
• Diverging UV and Halpha fluxes of star forming galaxies predicted by the IGIMF theory
• Young Stellar Groups and Their Most Massive Stars
• Why haven't loose globular clusters collapsed yet?
• Dependency of dynamical ejections of O stars on the masses of very young star clusters
• Implications of White Dwarf Galactic Halos
• Low-mass X-ray binaries indicate a top-heavy stellar initial mass function in ultra compact dwarf galaxies
• The Origin of the Arches Stellar Cluster Mass Function
• The Theoretical Mass--Magnitude Relation of Low-Mass Stars and its Metallicity Dependence
• Stellar clusterings around "Isolated" Massive YSOs in the LMC
• The Effect of Star Formation History on the Inferred Initial Stellar Mass Function
• The Magellanic Bridge cluster NGC 796: Deep optical AO imaging reveals the stellar content and initial mass function of a massive open cluster
• Mass-loss and expansion of ultra compact dwarf galaxies through gas expulsion and stellar evolution for top-heavy stellar initial mass functions
• Star formation in the outskirts of DDO 154: A top-light IMF in a nearly dormant disc
• Variations in the Mass Functions of Clustered and Isolated Young Stellar Objects
• Photometric determination of the mass accretion rates of pre-main sequence stars. V. Recent star formation in the 30 Dor nebula
• A Possible Solution for the $M/L-[Fe/H]$ Relation of Globular Clusters in M31. II. the Age-Metallicity Relation
• Very massive stars in not so massive clusters
• A Possible Solution for the M/L-[Fe/H] Relation of Globular Clusters in M31: A metallicity and density dependent top-heavy IMF
• Was the Milky Way a chain galaxy? Using the IGIMF theory to constrain the thin-disk star formation history and mass

Cited by in corpus (4)

• Dynamical Evolution of Multiple-Population Globular Clusters
• Radial variation of the stellar mass functions in the globular clusters M15 and M30: clues of a non-standard IMF?
• Stellar Initial Mass Function over a range of redshifts
• Compact object populations over cosmic time I. BOSSA: a Binary Object environment-Sensitive Sampling Algorithm