New Time!
CCAPP Cosmology Lunch meets on Wednesdays at 1:00 pm in the Price Place (PRB M2005).


December, 1  2016

November, 17 2016

    Special talk: 
    Michael Wilson
    University of Edinburgh
    
    "Geometric and growth rate tests of gravity with the linearised galaxy distribution"

    Abstract:
    This talk will outline the consistency of the VIPERS PDR-2 census of the galaxy distribution at z=0.8 with the expansion history and linear growth rate predicted by General Relativity and a Planck (2015) cosmology.  These may be inferred from the observed anisotropy of the galaxy power spectrum, which is sensitive to both the coherent infall of galaxies towards clusters (outflow from voids) and the assumption of an expansion history differing from the true one.
    I will then present the results of including a simple density transform prior to the analysis; this tackles the principal cause of non-linearity by down-weighting the most massive structures and extends the validity of theoretical models.  Moreover, this weighting would amplify signatures of modified gravity in ‘shielded’ models and represents a higher-order statistic, which contains information beyond that available to the power spectrum.
    Finally, the final data release of the VIPERS spectroscopic survey will be on Nov 18th (http://vipers.inaf.it).  I will detail the characteristics of the survey and describe the breadth of the accompanying clustering analyses.



November, 10  2016

November, 3  2016

October, 27 2016

    Special talk: 
    Patrick Breysse
    John Hopkins University
    
    "High-Redshift Astrophysics Using Every Photon"

    Abstract:
    Large galaxy surveys have dramatically improved our understanding of the complex processes which govern gas dynamics and star formation in the nearby universe. However, we know far less about the most distant galaxies, as existing high-redshift observations can only detect the very brightest sources. Intensity mapping surveys provide a promising tool to access this poorly-studied population. By observing emission lines with low angular resolution, these surveys can make use of every photon in a target line to study faint emitters which are inaccessible using traditional techniques. With upcoming carbon monoxide experiments in mind, I will demonstrate how an intensity map can be used to measure the luminosity function of a galaxy population, and in turn how these measurements will allow us to place robust constraints on the cosmic star formation history. I will then show how cross-correlating CO isotopologue lines will make it possible to study gas dynamics within the earliest galaxies in unprecedented detail.



October, 20  2016

October, 6  2016

September, 29  2016

September, 22  2016

September, 15  2016


September, 8  2016


September, 1  2016