Kinematics of the Nebular Complex MH9/10/11 Associated with HoIX X-1

TL;DR

This study investigates the kinematics and physical properties of the nebular complex MH9/10/11 associated with ULX HoIX X-1, revealing distinct regions with different velocities, ionization states, and chemical abundances, using Fabry-Perot interferometry.

Contribution

It provides detailed kinematic analysis and physical characterization of the nebulae associated with ULX HoIX X-1, highlighting differences in their expansion, ionization, and composition.

Findings

MH9/10 shows expansion velocities of 20-70 km/s with asymmetry.

MH11 has low velocity dispersion (~15 km/s) and solar oxygen abundance.

Photoionization by a source of about 10^39 erg/s explains MH11 properties.

Abstract

We report the results of our observations of the nebular complex MH9/10/11, associated with the ULX HoIX X-1, with scanning Fabry-Perot Interferometer. Two regions differing by their kinematics and line ratios may be distinguished, roughly corresponding to the bubble nebula MH9/10 and fainter HII-region MH11. For MH9/10 we find the expansion rate of 20-70km/s that is different for the approaching and receding parts. MH11 is characterised by very low velocity dispersion (less than or about 15km/s) and nearly constant line-of-sight velocities. Properties of MH11 may be explained by photoionization of gas with hydrogen density of about 0.2cm^-3. Luminosity required for that should be of the order of 10^39erg/s. Similar power source is required to explain the expansion rate of MH9/10. Modelling results also indicate that oxygen abundance in MH11 is about solar.