I went to the “DPG Spring Meeting of the Division Particle Physics” at the Karlsruhe Institute of Technology. I gave a short 12-minute talk about progress on spatially coherent reconstructions of the Galactic HI and H2 gas densities, velocities and emission line widths (which contain information about e.g. temperature).
Title: Spatially Coherent 3D Distributions of HI and CO in the Milky Way
Abstract: The spatial distribution of the gaseous components of the Galaxy is of great importance for interpreting and modelling cosmic ray data and diffuse emission. Reconstructing interstellar gas from doppler-shifted line emission requires knowledge of gas velocities and generally suffers from distance ambiguities.
We overcome these issues by reconstructing the posterior distribution of 3D HI and CO gas densities and velocities in a common Bayesian inference scheme. We explicitly enforce a spatially coherent structure by means of modelling the 3D fields as correlated (log)normal random fields.
For the first time, we include the modelling of absorption effects, which are especially important for the usually optically thick CO emission lines. We also improve on previous reconstructions by promoting the galactic velocity field and the emission line widths to the set of reconstructed fields, and further constrain their values with complementary data from galactic masers.
We provide a spatially coherent large-scale picture of the 3D distribution of gas in the Galaxy and illustrate the value of these maps in predicting diffuse gamma-ray emission.
Authors: Laurin Söding, Philipp Mertsch, and Vo Hong Minh Phan
When: 04th of March 2024
Where: Karlsruhe Institute for Technology
This is a link to information about my talk on the conference-webpage. Below, you can find the slides of my presentation in pdf format: