Wine and Cheese Fall 2020

This page records the schedule, titles and abstracts of the JHU/STScI CAS Astrophysics Wine & Cheese Series in Fall 2020.

Wine and Cheese sessions with one speaker will have a 50 minute talk with 10 minutes for questions. Sessions with two speakers will have two 25 minute talks, each with 5 minutes for questions. Sessions in the Graduate Student Series will have three 15 minute talks, each with 5 minutes for questions.

21 September

Jose Luis Bernal Mera (JHU)

Cosmology with Large-Scale Structure Clustering and Implications for Early Dark Energy Models
During the last decade, measurements of the galaxy clustering have become one of the cornerstones for our understanding of the Universe. With next-generation galaxy surveys and the promise of line-intensity mapping experiments, observations will be more precise will probe regimes that have been unexplored so far. In this talk we will review the cosmological information encoded in large-scale structure clustering and discuss the validity and reach of standard measurements. We also will review recent claims of galaxy clustering ruling out early dark energy models as a solution for the Hubble constant tension: although we agree with the results of the analyses performed, we reckon that such results are driven by the choice of prior and potential tensions between different observables, hence concluding that early dark energy is still a viable model and potential solution for the Hubble constant tension.

David Nataf (JHU)

Recent developments in the study of the distance and extinction to the Large and Small Magellanic Cloud
The Small and in particular the Large Magellanic Clouds (LMC) remain important anchors both to the extragalactic distance scale and to stellar astrophysics in general. As virtually all classes of variable stars and all classes of distance indicators have been studied in the LMC, it is possible and necessary to evaluate if these are consistent. I will begin my talk by first reviewing a surprising recent development. There is a 0.18 mag in the zero-point of the V-band extinction to the LMC, which vastly exceeds the quoted errors of virtually all prior studies of the matter. I will then discuss how our recent paper (https://arxiv.org/abs/2006.03603) resolved this issue, concurrently with another independent effort (https://arxiv.org/abs/2006.02448), using four different calibrations: stellar isochrones, RR Lyrae stars, Cepheids, and the SFD extinction maps. The resulting error is decreased to <~ 0.04 mag.