Physics & Astronomy - Cosmology Seminar - Prof. Douglas Finkbeiner, Harvard
Title: "3D Dust Maps and Gamma-Ray Foregrounds for Dark Searches"
Abstract: Dust emission maps have long been used to estimate total reddening, integrated along the line of sight. These 2D maps are not adequate for reddening estimates within the Milky Way, where the object of interest may not be behind all of the dust. Using colors of 800,000,000 stars from 2MASS and Pan-STARRS, we can now infer the location of reddening along each line of sight in about 30 distance bins, making a crude 3D dust map with ~ 5 arcmin angular pixels over 3/4 of the sky. One application of such a map is to calculate gamma-ray emission from cosmic ray interaction with the interstellar matter and radiation field. These gamma-ray "foregrounds" are a major nuisance limiting searches for gamma-rays from dark matter annihilation.