12:00–1:00 pm ERC 501
Host: Jeff McMahon
Rebecca Diesing "Understanding the multi-wavelength emission from astrophysical shocks"
Interpreting observations of the universe’s most energetic phenomena requires a detailed understanding of particle acceleration in astrophysical environments. In particular, these accelerated particles, or cosmic rays, are responsible for the non-thermal emission observed in supernova remnants, novae, AGN winds, and a host of other astrophysical shocks. In this chalk talk, I will review the standard paradigm of shock acceleration and show how incorporating results from kinetic simulations can refine our interpretations of observations. In particular, I will show how self-consistent modeling can be used to explain radio and gamma-ray spectra inferred from Galactic supernova remnants, the radio and X-ray observations from extragalactic supernovae ("radio supernovae"), the GeV and TeV emission detected from the recent outburst of recurrent nova RS Ophiuchi, and the gamma-rays detected from fast AGN winds.
Zhuowen Zhang "Covariance modeling for cluster weak lensing observables"
Galaxy cluster abundance is one of the pillars of modern cosmology, with weak-lensing the gold standard for cluster mass calibration. Despite this achievement in modern cosmology, uncertainties and systematics in cluster observables hamper this probe in cosmological studies. We provide for the first time a model for the intrinsic correlated scatter between weak lensing signal and cluster richness and find a negative correlation between lensing signal and galaxy number count at small scales which can be quantitatively accounted for by the halo formation history.
I will make this talk useful for people outside of cluster cosmology by introducing statistical methods as multi-linear regression and test of (multivariate)-Gaussianity in our validation of the covariance.
