论文标题
Tycho Supernova Remnant中同步加速器X射线条纹的时间和空间变化
Temporal and Spatial Variation of Synchrotron X-ray Stripes in Tycho's Supernova Remnant
论文作者
论文摘要
在Tycho的超新星残留物（SNR）中发现的同步X射线“条纹”引起了人们的注意，因为它们可能是PEV质子加速的证据。我们分析了Chandra在2003年，2007年，2009年和2015年获取的Chandra数据，用于SNR西南地区的条纹成像和光谱。比较在不同时期获得的图像，我们发现同步子X射线的时间变化不限于先前报道的两个结构，但在该区域更为常见。对九种亮条纹的光谱分析不仅揭示了它们的时间变化，而且还揭示了表面亮度和光子指数之间的强烈反相关。九个条纹的光谱具有γ= 2.1--2.6的光子指数，并且比同一区域中SNR外边缘的光子指数明显硬，γ= 2.7--2.9。基于这些发现，我们表明磁场已大大扩增，并建议通过随机过程加速粒子可能在条纹中起作用。
The synchrotron X-ray "stripes" discovered in Tycho's supernova remnant (SNR) have been attracting attention since they may be evidence for proton acceleration up to PeV. We analyzed Chandra data taken in 2003, 2007, 2009, and 2015 for imaging and spectroscopy of the stripes in the southwestern region of the SNR. Comparing images obtained at different epochs, we find that time variability of synchrotron X-rays is not limited to two structures previously reported but is more common in the region. Spectral analysis of nine bright stripes reveals not only their time variabilities but also a strong anti-correlation between the surface brightness and photon indices. The spectra of the nine stripes have photon indices of Γ= 2.1--2.6 and are significantly harder than those of the outer rim of the SNR in the same region with Γ= 2.7--2.9. Based on these findings, we indicate that the magnetic field is substantially amplified, and suggest that particle acceleration through a stochastic process may be at work in the stripes.
