086532

The X-ray spectrum of the colliding-wind binary WR140 at apastron is produced under benign conditions of minimum density and minimum orbital velocity and forms the initial plasma state from which subsequent evolution occurs. The star.s precise orbit comma exceptional X-ray brightness comma rich observational history and characteristic X-ray temperature very similar to that of the Perseus Cluster of Galaxies make it the ideal reference for calibration of models of plasmas produced under dynamical and thermodynamical conditions similar to those that hold in a variety of prominent X-ray sources. As well as precise tests of predicted photometry comma a joint RGS-HETG high-resolution spectrum will test a predicted emission-line redshift at apastron.

星风碰撞双星WR140在远星点(apastron)处的X射线光谱，是在最低密度与最低轨道速度的温和条件下生成的，其构成了后续等离子体演化的初始状态。该天体拥有精确可测的轨道、卓越的X射线亮度、丰富的观测历史，且特征X射线温度与英仙座星系团(Perseus Cluster of Galaxies)高度相似，使其成为校准等离子体模型的理想参照——这类等离子体的动力学与热力学条件，与各类知名X射线源中的等离子体条件相一致。除了对预测的测光结果开展精确检验外，一套联合反射光栅光谱仪-高能量透射光栅光谱仪(RGS-HETG)的高分辨率光谱，还将验证远星点处预测的发射线红移。