DOI

https://doi.org/10.48717/wpmq-v549

Project

EM165

Title

e-EVN: EM165A, EA071A

Abstract

Gamma-ray binaries (gBs) are powerful systems that are able to radiate from radio to TeV energies. HESS J1832-093 is one of the handful of gBs known in our Galaxy, only confirmed as such in 2020. With a period of 86 days, this source lies well in the middle between the gBs with short periods (~4-10 days) and long ones (~1-4 years). HESS J1832-093 is thought to be associated with a supernova remnant that appears in the same field: G22.7-0.2, at 4.4 kpc from the Earth. Exploratory EVN observations in Nov 2016 revealed a compact radio emission from HESS J1832-093. We now request six e-EVN epochs on the source to constrain its proper motion and parallax. We would thus accurately determine the distance to HESS J1832-093 and its peculiar motion (the region is highly obscured and even Gaia cannot see the system). We would then clarify its possible association with G22.7-0.2, and determine the luminosity of the source at different wavelengths. This would allow us to place HESS J1832-093 with respect to other luminous (like LS I +61 303) or underluminous (HESS J0632+057) gBs.