Measuring H_0 with the DES Supernova Inverse Distance Ladder
Date Submitted
2017-04-14 13:43:50
Ed Macaulay
ICG Portsmouth
The precise value of Hubble’s Constant H_0 has become one of the most hotly contested cosmological parameters in recent years. Local measurements of H_0, based on a distance ladder of parallax, cepheid variable stars, and type Ia Supervonae, find a value of H_0 = 73.24±1.74 km/s/Mpc. However, inferences of H_0 based on the LCDM model and parameters measured from the CMB suggest a lower value of H_0 = 66.93±0.62. This discrepancy may be indicative of unaccounted for systematic effects with either measurement, or may be hinting at interesting new physical phenomena, such as large-scale inhomogeneities, or extra relativistic particles. In this talk, I’ll focus on a new measurement of H_0 with the DES Supernova Program and an inverse distance ladder method. By calibrating the supernova magnitudes to geometrical distances from Baryon Acoustic Oscillation measurements, we can find a measurement of H_0 which is less sensitive to local inhomogeneities or choice of fiducial model. I will also discuss our techniques for performing a blind analysis, to reduce our sensitivity to confirmation bias.
Schedule
id
Monday
date time
16:30 - 18:00
16:50
Abstract
Measuring H_0 with the DES Supernova Inverse Distance Ladder