A 3D extinction map of the Northern Galactic Plane based on IPHAS photometry

TL;DR

This paper presents a high-resolution 3D extinction map of the Northern Galactic Plane using IPHAS survey data, employing a hierarchical Bayesian model to estimate extinction and stellar parameters for millions of stars.

Contribution

It introduces a detailed 3D extinction map with differential extinction measurements, based on a hierarchical Bayesian approach, and provides stellar parameter estimates for nearly 38 million stars.

Findings

High angular and distance resolution extinction map

Measurement of differential extinction due to ISM fractal structure

Provision of stellar parameters for millions of stars

Abstract

We present a three dimensional map of extinction in the Northern Galactic Plane derived using photometry from the IPHAS survey. The map has fine angular ($\sim 10$ arcmin) and distance (100 pc) sampling allied to a significant depth ($\gtrsim 5$ kpc). We construct the map using a method based on a hierarchical Bayesian model as previously described by Sale (2012). In addition to mean extinction, we also measure differential extinction, which arises from the fractal nature of the ISM, and show that it will be the dominant source of uncertainty in estimates of extinction to some arbitrary position. The method applied also furnishes us with photometric estimates of the distance, extinction, effective temperature, surface gravity, and mass for $\sim 38$ million stars. Both the extinction map and the catalogue of stellar parameters are made publicly available via http://www.iphas.org/extinction .