Modeling of the Vela complex including the Vela supernova remnant, the binary system γ² Velorum, and the Gum nebula

¹ Humboldt Universität zu Berlin, Institut für Physik, Berlin, Germany
e-mail: yusushch@physik.hu-berlin.de
² National Taras Shevchenko University of Kyiv, Department of Physics, Kyiv, Ukraine
³ National Taras Shevchenko University of Kyiv, Astronomical Observatory, Kyiv, Ukraine
⁴ ISDC, Versoix, Switzerland

Received: 6 July 2010
Accepted: 18 October 2010

Abstract

We study the geometry and dynamics of the Vela complex including the Vela supernova remnant (SNR), the binary system γ² Velorum and the Gum nebula. We show that the Vela SNR belongs to a subclass of non-Sedov adiabatic remnants in a cloudy interstellar medium (ISM), the dynamics of which is determined by the heating and evaporation of ISM clouds. We explain observable characteristics of the Vela SNR with a SN explosion with energy 1.4 × 10⁵⁰   erg near the step-like boundary of the ISM with low intercloud densities (~10^-3   cm^-3) and with a volume-averaged density of clouds evaporated by shock in the north-east (NE) part about four times higher than the one in the south-west (SW) part. The observed asymmetry between the NE and SW parts of the Vela SNR could be explained by the presence of a stellar wind bubble (SWB) blown by the nearest-to-the Earth Wolf-Rayet (WR) star in the γ² Velorum system. We show that the size and kinematics of γ² Velorum SWB agree with predictions of numerical calculations for the evolution of the SWB of M_ini = 35   M_⊙ star. The low initial mass of the WR star in γ² Velorum implies that the luminosity of the nuclear line of ²⁶Al, produced by γ² Velorum, is below the sensitivity of existing gamma-ray telescopes.