Non-thermal emission from Massive Young Stellar Objects

TL;DR

This paper investigates non-thermal emissions from massive young stellar objects by modeling wind interactions and shock acceleration, predicting observable synchrotron and gamma-ray signals.

Contribution

It introduces hydrodynamical models combined with non-thermal particle acceleration calculations for YSOs, a novel approach in this context.

Findings

Hydrodynamical models predict significant non-thermal emission from YSO outflows.

Shock acceleration processes can produce relativistic particles detectable via gamma-ray observations.

Predicted emissions could be observed with current or upcoming high-energy telescopes.

Abstract

In the young stellar object (YSO) phase of their lives, massive stars drive bi-polar molecular outflows. These outflows produce beautiful, often hourglass shaped, cavities. The central star possesses a powerful stellar wind (v ~ 2000 km s^-1), and possibly a dense equatorial disk wind (v ~ 400 km s^-1), which collide with the inner surface of the bi-polar cavity and produces hot (T ~ 10^5 - 10^8 K) shocked plasma. A reverse shock is formed at the point where the ram pressure between the preshock flow balances the thermal pressure of the postshock flow and provides a site for the acceleration of non-thermal particles to relativistic energies. Hydrodynamical models of the wind interaction, coupled with calculations of the non-thermal energy spectrum, are used to explore the observable synchrotron and gamma-ray emission from these objects.