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Galactic-Field Initial Mass Functions of Massive Stars
Over the past years observations of young and populous star clusters have shown that the stellar initial mass function (IMF) appears to be an invariant featureless Salpeter power law with an exponent
Galactic-Field IMFs of Massive Stars
Over the past years observations of young and populous star clusters have shown that the stellar IMF appears to be an invariant featureless Salpeter power-law with an exponent alpha=2.35 for stars
Evidence for a fundamental stellar upper mass limit from clustered star formation
The observed masses of the most massive stars do not surpass about 150 M ○. . This may either be a fundamental upper mass limit which is defined by the physics of massive stars and/or their
The variation of integrated star initial mass functions among galaxies
The integrated galaxial initial mass function (IGIMF) is the relevant distribution function containing the information on the distribution of stellar remnants, the number of supernovae, and the
The relation between the most-massive star and its parental star cluster mass
We present a thorough literature study of the most-massive star, mmax, in several young star clusters in order to assess whether or not star clusters are populated from the stellar initial mass
Implications for the formation of star clusters from extragalactic star formation rates
Observations indicate that young massive star clusters in spiral and dwarf galaxies follow a relation between luminosity of the brightest young cluster and the star formation rate (SFR) of the host
Converting Hα Luminosities into Star Formation Rates
Star-formation rates (SFRs) of galaxies are commonly calculated by convert- ing the measured Hluminosities (LH�) into current SFRs. This conversion is based on a constant initial mass function (IMF)
The maximum stellar mass, star-cluster formation and composite stellar populations
We demonstrate that the mass of the most massive star in a cluster correlates non-trivially with the cluster mass. A simple algorithm, according to which a cluster is filled up with stars that are
The (galaxy-wide) IMF in giant elliptical galaxies: From top to bottom
Recent evidence based independently on spectral line strengths and dynamical modelling point towards a non-universal stellar Initial Mass Function (IMF), probably implying an excess of low-mass stars
The masses, and the mass discrepancy of O-type stars
Context. The “mass discrepancy” in massive O stars represents a long-standing problem in stellar astrophysics with far-reachin g implications for the chemical and dynamical feedback in galaxies.