标题： 银河系附近的热金属的限制 显示英文标题

标题： Constraints on hot metals in the Vicinity of the Galaxy

摘要： 我们搜索了银河系附近的热金属引起的软X射线吸收证据，在一个由十五个I型活动星系核（AGN）组成的样本的光谱中，这些样本使用钱德拉卫星上的高分辨率X射线光栅观测。 这是对我们之前关于银河系附近热OVII和OVIII吸收气体调查的延伸。 在它们静止能量几百公里/秒范围内的最强吸收特征最有可能是由最近的AGN的温暖吸收外流引起，它们正在照亮局部热气体。 我们强调，一些遥远AGN光谱中的吸收特征如果在动力学上与AGN的退行速度一致，很可能是由于局部热气体引起的。 沿着PG 1211+143、PDS 456和MCG-6-30-15的方向，存在一个非常大的吸收Fe列密度，这在动力学上与被热、局部Fe吸收一致。 这三条AGN视线穿过北方极盖（NPS）的边缘，这是一个由几次超新星形成的局部气泡，如果富含Fe，可能解释了大量局部Fe列。 我们在样本中所有视线方向上得到了局部高度电离N、Ne、Mg、Si的列密度限制。 我们将这些视线方向上高度电离O的列密度限制进行相关性分析。 假设局部热气体处于碰撞电离平衡状态，我们得到了局部热气体中金属温度和相对丰度的限制。 我们对局部热气体中离子列密度的限制似乎与正常盘状星系边视面热晕气体中观察到的限制一致。 显示英文摘要

摘要： We have searched for evidence of soft X-ray absorption by hot metals in the vicinity of the Galaxy in the spectra of a small sample of fifteen Type I AGN observed with the high resolution X-ray gratings on board Chandra. This is an extension of our previous survey of hot OVII and OVIII absorbing gas in the vicinity of the Galaxy. The strongest absorption signatures within a few hundred km/s of their rest-frame energies are most likely due to warm absorbing outflows from the nearest AGN, which are back-lighting the local hot gas. We emphasize that absorption signatures in the spectra of some distant AGN that are kinematically consistent with the recessional velocity of the AGN are most likely to be due to hot local gas. Along the sightline towards PG 1211+143, PDS 456 and MCG-6-30-15 there is a very large absorbing Fe column density which is kinematically consistent with absorption by hot, local Fe. The sightlines to these three AGN pass through the limb of the Northern Polar Spur (NPS), a local bubble formed from several supernovae which, if rich in Fe, may account for a large local Fe column. We obtain limits on the column density of local, highly ionized N, Ne, Mg, Si along all of the sightlines in our sample. We correlate the column density limits with those of highly ionized O along the same sightlines. Assuming the hot local gas is in collisionally ionized equilibrium, we obtain limits on the temperature and relative abundances of the metals in the hot local gas. Our limits on the ionic column densities in the local hot gas seem to be consistent with those observed in the hot halo gas of edge-on normal spiral galaxies.