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Long-Term Evolution of Supernova Remnants in Magnetized Interstellar Medium

Hidekazu Hanayama·Kohji Tomisaka
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Abstract

The evolution of supernova remnants (SNRs) is studied, with particular attention to the effect of magnetic fields with axisymmetric two-dimensional magnetohydrodynamical simulations. The evolution of magnetic SNRs is the same as non-magnetic ones in the adiabatic Sedov stage. After a thin shell is formed, the shell is driven by the pressure of the hot interior gas (bubble). Evolution in the pressure-driven snow-plow phase is much affected by the magnetic field. The shell sweeping the magnetic field lines thickens owing to the magnetic pressure force. After $5\times 10^5{\rm yr}$ - $2\times 10^6{\rm yr}$, the inner boundary of the thick shell begins to contract. This compresses the hot bubble radially and maintains its thermal pressure. Thus, the bubble forms a prolate spheroidal shape and becomes thinner and thinner, since it expands in a direction parallel to the magnetic field for $B_0 \gtrsim 3μ{\rm G}$. Finally, the bubble contracts. The porosity of the hot low-density gas in ISM is reduced, taking the effect of the magnetic field into account.

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Hidekazu Hanayama, Kohji Tomisaka. 2005-07-19. Long-Term Evolution of Supernova Remnants in Magnetized Interstellar Medium. https://doi.org/10.1086/500527

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