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Today's Colloquium: The too-big-to-fail problem is too-persistent-to-die: new constraints from nearby field dwarfs

Submitter: Manolis Papastergis
Description: The "too big to fail" (TBTF) problem is a pressing observational challenge to the standard cosmological model at small scales. Put simply, it refers to the fact that it is very challenging to explain both the internal kinematics and the observed number density of dwarfs in the LCDM context. Even though the problem was first identified in the satellite population of the Milky Way, it has now become clear that it concerns dwarf galaxies in general.

In this talk, I first plan to give an overview of the observational evidence that supports the statements above. I then plan to discuss two promising non-cosmological solutions to the problem: The first comes from the theory side, and consists of incorporating a number of baryonic feedback effects into our theoretical model. The second comes from the observational side, and has to do with the ability of HI kinematics to accurately trace the underlying dark mater potential of dwarfs. I will conclude by showing how present and future observations of HI in nearby field dwarfs can help us distinguish between cosmological and non-cosmological solutions for TBTF.
Copyright: Manolis Papastergis (Kapteyn)
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