Abstract Details
| Name: Indulekha Kavila Affiliation: Mahatma Gandhi University Conference ID: ASI2017_956 Title : IMF Variations and the Small Variations in Fundamental Star Formation Relations Authors and Co-Authors : Remya T C Arundhathy V J Abstract Type : Poster Abstract Category : Stars,ISM and the Galaxy Abstract : The Initial Mass Function of the stars is a key input into galaxy evolution models. Long lived low mass stars contribute to the mass budget while high mass stars, which are capable of injecting much energy, momentum and metals into their surroundings, are the drivers of evolution. Also, an understanding of the universality / non-universality / environment sensitive universality of the IMF is needed for constraining cosmological models through matching the observations of galaxies with cosmological simulations of structure formation. For instance, a bottom heavy IMF, as recently inferred for Early Type Galaxies in their central regions, from observations of gravity sensitive features in their spectrum, is degenerate with dark matter / non-Newtonian gravity in its impact on the mass to light ratio of the system. Though the formation of high mass stars is an ill-understood phenomenon, universality is expected for the IMF, on the grounds of the scale-free nature of both turbulence and gravity, the key factors operating in turbulent fragmentation models of star formation. However, the statistical expectation that the most massive star in a more numerous sample is more likely to be more massive than the most massive star of a less numerous sample, leads to expectations of non-universality associated with regional variations in the star formation rate / efficiency. Here, we explore the effect of such a non-universality of the IMF, on estimates of the star formation rates made from measured fluxes in various wavelength bands / spectral features. We further look into how and whether such a bias could introduce a tension between the average (over varying star forming conditions) behaviour and away from the mean behaviour, of the relation between star formation and the environment. |