AI 中文总结
该研究通过一维流体力学模拟，发现星周风泡会显著增大脉冲星风云尺寸与能量，解释了部分脉冲星风云尺寸偏大、其母超新星遗迹未被探测的现象。
AI 中文摘要
大质量恒星的核心坍缩超新星爆发后，会形成超新星遗迹（SNR）与脉冲星风云（PWN）系统，其演化部分取决于周围环境，而该环境常被假定为典型星际介质（ISM）。但大质量恒星在生命周期中会释放强风，刻画出被称为风泡（WBB）的延展星周空腔。我们研究了WBB对SNR-PWN系统动力学、能量学及热X射线辐射的影响，针对不同恒星前身星和脉冲星参数，在WBB或ISM环境中开展系统的一维流体力学模拟。该系统初始在WBB低密度内部膨胀至大尺寸，直至SNR充满整个气泡；对于质量为8倍太阳质量（20倍太阳质量）的前身星，约5千年（2.5万年）后PWN尺寸增长至10秒差距以上（30秒差距），是ISM环境中的5-6倍。SNR对WBB大质量外壳的冲击会产生强反射激波，将能量高效返还至系统内部；后期PWN被压缩一个数量级后，空腔内的往返激波交叉使SNR维持在极高温度，驱动PWN剧烈回响，半径变化可达3-4倍，此阶段PWN平均尺寸为ISM环境的2-4倍，能量多一个数量级。系统热辐射表现为少量局域化爆发，当激波撞击气泡外壳时，低速激波穿过外壳产生辐射。WBB为解释许多PWN的大尺寸及其母SNR未被探测到的现象提供了可能。
英文摘要
The core-collapse supernova explosion of most massive stars is followed by the development of a supernova remnant (SNR) and pulsar wind nebula (PWN) system whose evolution is in part dictated by its surrounding environment. The latter is frequently assumed to be the typical interstellar medium (ISM). However, massive stars emit powerful winds during their lifetime and carve extended circumstellar cavities known as wind-blown bubbles (WBBs). We investigated the impact of WBBs on the dynamics, energetics, and thermal X-ray emission of a SNR-PWN system. We performed numerical simulations of a 1D hydrodynamical analogue of the system, for different stellar progenitors and pulsar parameters, in a WBB or ISM environment. The system initially expands to large sizes in the low-density interior of a WBB, until the SNR fills the entire bubble. The PWN grows to $\gtrsim10~\mathrm{pc}$ ($30~\mathrm{pc}$) after $\sim5~\mathrm{kyr}$ ($\sim25~\mathrm{kyr}$) for a $M=8~\mathrm{M}_\odot$ ($M=20~\mathrm{M}_\odot$) progenitor, $5-6$ times larger than in an ISM environment. The impact of the SNR on the massive outer shell of the WBB generates a strong reflected shock that efficiently returns energy to the inner parts of the system. At late times, after a strong compression of the PWN by an order of magnitude in size, back-and-forth shock crossings of the cavity maintain the SNR at very high temperatures and drive a vigorous reverberation of the PWN, with changes in radius by up to $3-4$. In this stage, the PWN is on average $2-4$ times larger than in an ISM environment and contains up to an order of magnitude more energy. Thermal radiation from the system occurs in few very localised emission bursts, as low-velocity shocks are transmitted across the bubble shell when it is hit by blast waves. WBBs offer a possible explanation for the large sizes of many PWNe and the non-detection of their parent SNRs.
Comments12 pages, 6 figures, accepted for publication by Astronomy & Astrophysics
DOI：10.1051/0004-6361/202661049
