Approximate analytical description of the high latitude extinction

TL;DR

This paper presents an analytical 3D model of interstellar extinction in the Northern sky, derived from LAMOST and Gaia data, enabling predictions of extinction for stars with known parallaxes.

Contribution

The authors develop a novel analytical model of interstellar extinction using spherical harmonics, improving the prediction of extinction values across the sky.

Findings

Mapped $A_V$ distribution over the Northern sky.

Created a spherical harmonic approximation of the extinction model.

The model can predict extinction for stars with known parallaxes.

Abstract

The distribution of visual interstellar extinction $A_V$ has been mapped in selected areas over the Northern sky, using available LAMOST DR5 and Gaia DR2/EDR3 data. $A_V$ was modelled as a barometric function of galactic latitude and distance. The function parameters were then approximated by spherical harmonics. The resulting analytical tridimensional model of the interstellar extinction can be used to predict $A_V$ values for stars with known parallaxes, as well as the total Galactic extinction in a given location in the sky.