Chandra X-Ray Observatory Arcsecond Imaging of the Young, Oxygen-rich Supernova Remnant 1E 0102.2-7219

How high energy fluxes may affect Rayleigh-Taylor instability growth in young supernova remnants

Energy-transport effects can alter the structure that develops as a supernova evolves into a supernova remnant. The Rayleigh–Taylor instability is thought to produce structure at the interface between the stellar ejecta and the circumstellar matter, based on simple models and hydrodynamic simulations. Here we report experimental results from the National Ignition Facility to explore how large energy fluxes, which are present in supernovae, affect this structure. We observed a reduction in Rayleigh–Taylor growth. In analyzing the comparison with supernova SN1993J, a Type II supernova, we found that the energy fluxes produced by heat conduction appear to be larger than the radiative energy fluxes, and large enough to have dramatic consequences. No reported astrophysical simulations have included radiation and heat conduction self-consistently in modeling supernova remnants and these dynamics should be noted in the understanding of young supernova remnants.

Radiation and conduction are generally considered as the main energy transport mechanisms for the evolution of early supernova remnants. Here the authors experimentally show the role of electron heat transfer on the growth of Rayleigh–Taylor instability in young supernova remnants.

Generation of ultrahigh-velocity ionizing shocks with petawatt-class laser pulses

Ultrahigh-velocity shock waves (approximately 10,000 km/s or 0.03c) are generated by focusing a 350-TW laser pulse into low-density helium gas. The collisionless ultrahigh-Mach-number electrostatic shock propagates from the plasma into the surrounding gas, ionizing gas as it becomes collisional. The shock undergoes a corrugation instability due to propagation of the ionizing shock within the gas (the Dyakov-Kontorovich instability). This system may be relevant to the study of very high-Mach-number ionizing shocks in astrophysical situations.

Recent X-ray observations of supernova remnants

The imaging and spectral capabilities of the Chandra X-ray Observatory and XMM-Newton are extremely well suited for studying the remnants of supernovae. High-resolution imaging over the band 0.1-10 keV maps the detailed structure of the supernova remnant, delineates the forward and reverse shock fronts and facilitates proper motion studies of the expanding material. High-resolution spectroscopy enables detailed diagnostics of the emitting plasma, including temperatures, ionization balance and abundances. Spectroscopy also reveals Doppler velocities along the line of sight. Most powerful is the capability for imaging spectroscopy, which can probe the progressive ionization at the shock fronts, the elemental distribution in the ejecta, and Doppler imaging. Examples are drawn from recent studies of oxygen-rich supernova remnants of various ages.