MIT HOLIDAY NOVEMBER 11 — NO BROWN BAG LUNCH TALK

Monday November 11, 2013 12:05 pm

Please note that due to the MIT holiday on November 11 there is no Brown Bag Lunch Talk scheduled.  The next Brown Bag Lunch Talk is scheduled for November 18:

Advances in galaxy-formation simulations: calculating mock observables & using a more-accurate numerical technique
Speaker: Chris Hayward, MPIA/Heidelberg
Host: Anna Frebel

Abstract
Galaxy formation has been studied using idealized numerical simulations of isolated disk galaxies and galaxy mergers for decades, but most simulations performed to date have suffered from two potentially significant limitations: First, when comparing simulations with observations, physical quantities – rather than observables – from the simulations are used. Second, the most-commonly used techniques, smoothed-particle hydrodynamics (SPH) and adaptive mesh refinement, suffer from numerical inaccuracies that can potentially jeopardize the results of simulations performed with those techniques. I will discuss methods for solving both of these limitations. I address the first limitation by performing 3-D dust radiative transfer on hydrodynamical simulations to calculate spatially resolved UV-mm spectral energy distributions of simulated galaxies. I will present an application to submillimeter galaxies, for which a realistic comparison with observables yields results that are qualitatively different from those of more naive comparisons. I address the second limitation by using the more-accurate moving-mesh hydrodynamics code Arepo. I will discuss how merger simulations performed with the moving-mesh technique differ from otherwise identical simulations performed using SPH. Finally, based on this comparison and other work, I will outline the types of galaxy-formation simulations for which the traditional formulation of SPH is sufficiently accurate and describe when and why this is not the case.

The schedule for upcoming Brown Bag Lunch Talks can be viewed here: