标题： 同时的XMM-Newton和ESO VLT对SN 1995N的观测：探测风/喷发物相互作用 显示英文标题

标题： Simultaneous XMM-Newton and ESO VLT observations of SN 1995N: probing the wind/ejecta interaction

摘要： 我们展示了首次对互作用型IIn超新星1995N的{\it XMM-Newton}观测结果，该观测于2003年7月进行。 我们发现，0.2–10.0 keV的未吸收流量下降至$\simeq 1.8 \times 10^{-13}$erg cm$^{-2}$s$^{-1}$，比1998年1月的前一次{\it ASCA}观测值低将近一个数量级。 从所有可用的X射线测量数据来看，可以得出一个有趣的场景，即X射线辐射可能由双相（块状/平滑）的周边恒星介质产生。 X射线光谱分析显示了两个明显不同的组分存在的统计学显著证据，这些组分可以用不同温度下的光学薄热等离子体发射来建模。 从这些温度推断出的喷发物密度分布指数为$n\simeq 6.4$。 通过这两个光谱组分的流量，我们估算出了超新星前身天体的质量损失率${\dot M} \sim 2 \times 10^{-4} M_\odot {\rm yr}^{-1}$，处于红超巨星展示的区间上限。 协调的光学和红外观测使我们能够重建1995N超新星的同步红外到X射线流量分布。 我们发现，在爆炸后$\sim$年时，由于星风/喷流相互作用产生的直接X射线热辐射比总的再处理的红外/光学通量大$\sim 5$倍。 显示英文摘要

摘要： We present the results of the first {\it XMM-Newton} observation of the interacting type IIn supernova 1995N, performed in July 2003. We find that the 0.2--10.0 keV unabsorbed flux dropped at a value of $\simeq 1.8 \times 10^{-13}$ erg cm$^{-2}$ s$^{-1}$, almost one order of magnitude lower than that of a previous {\it ASCA} observation of January 1998. From all the available X-ray measurements, an interesting scenario emerges where the X-ray light emission may be produced by a two-phase (clumpy/smooth) circumstellar medium. The X-ray spectral analysis shows statistically significant evidence for the presence of two distinct components, that can be modeled with emission from optically thin, thermal plasmas at different temperatures. The exponent of the ejecta density distribution inferred from these temperatures is $n\simeq 6.4$. From the fluxes of the two spectral components we derive an estimate of the mass loss rate of the supernova progenitor, ${\dot M} \sim 2 \times 10^{-4} M_\odot {\rm yr}^{-1}$, at the upper end of the interval exhibited by red super-giants. Coordinated optical and infrared observations allow us to reconstruct the simultaneous infrared to X-ray flux distribution of SN 1995N. We find that, at $\sim$ 9 years after explosion, the direct X-ray thermal emission due to the wind/ejecta interaction is $\sim 5$ times larger than the total reprocessed IR/optical flux.