3/15/2021

Galaxies & Cosmology & Stars & Planets Seminar

Monday, March 15, 2021 - 11:00am

Zoom

Down the Rabbit Hole: Cold Gas Convergence in Cosmological Simulations

Speaker:

Max Gronke

Institution:

Johns Hopkins

Visitor Schedule

Host:

Anna Rosen

Abstract

Observations of the circumgalactic medium (CGM) have revealed cold gas structures ~<100pc in size -- and potentially much smaller. As these cannot be resolved directly in current cosmological simulations, it is maybe unsurprising that they are non-converged in these cold gas properties. This is highly worrying as this cold gas is the fuel for future star-formation, and it impacts many other processes we wish to study using those simulations such as ionizing photon escape. In this talk, I want to take you on a trip from Megaparsec to sub-parsec scales to answer the question if we can ever hope to obtain a converged solution, and if yes what resolution is required. To do so, I will present results from analytic theory and (magneto-)hydrodynamic simulations of simplified setups such as a single turbulent mixing layer and turbulent multiphase media.

Cosmology with Next-Generation Millimeter-Wave Spectrometers

Speaker2:

Kirit Karkare

Institution2:

University of Chicago

Visitor Schedule

Host2:

Marion Dierickx

Abstract

Line intensity mapping (LIM) is an emerging observational technique to measure the large-scale structure of the Universe in three dimensions, traced by a redshifted atomic or molecular line, without resolving individual objects. Future experiments promise to extend the observable volume beyond the redshift reach of traditional galaxy surveys, improving precision on the LCDM cosmological model and extensions to it. I will outline the science potential of LIM experiments targeting far-IR lines detectable at millimeter wavelengths, highlighting the need for dramatic improvement in sensitivity over current instruments. I will discuss how on-chip mm-wave spectrometer technology can provide this improvement. Finally I will introduce SPT-SLIM, a pathfinder for the South Pole telescope that will demonstrate LIM using on-chip spectrometers.

Event Status:

Active

3/15/2021

Events