论文标题
本地ISM中的不均匀性及其与Heliosphere的关系
Inhomogeneity in the Local ISM and its Relation to the Heliosphere
论文作者
论文摘要
本文回顾了过去的研究和新研究,对当地星际环境及其对地球圈的影响不断变化。在螺旋膜外部的气球的大小,形状和物理特性由周围环境(现在是局部星际云的外部区域(LIC)决定)。高分辨率HST光谱的分析导致具有许多星际云的运动学模型。该分析确定了位于太阳约10 pc及其平均温度,湍流和速度向量内的15个云。随着视线线数量的增加,现在正在分析视线线,我们发现温度和湍流速度在LIC和其他附近的云中具有空间变化,而其他云层比测量不确定性大得多,并且这些空间变化似乎是随机分布的,并且可以由高斯人拟合。不均匀的长度尺度小于4,000 au,这是在不到600年内横穿的距离。温度和湍流速度并未显示出与LIC中心的恒星距离或角度的明显趋势。如果/当太阳进入云间培养基时,未来的Heliosphere的物理特性将与现在大不相同。对于在螺旋桨外面的海旋和非常局部的星际介质(VLISM),总压力大约等于银河系中上覆材料的重力压力。 LIC中的内部压力远低于VLISM中的内部压力,但是LIC在其环境方面的流动产生了不确定的RAM压力术语。
This paper reviews past research and new studies underway of the local interstellar environment and its changing influence on the heliosphere. The size, shape, and physical properties of the heliosphere outside of the heliopause are determined by the surrounding environment - now the outer region of the Local Interstellar Cloud (LIC). Analysis of high-resolution HST spectra led to a kinematic model with many interstellar clouds. This analysis identified fifteen clouds located within about 10 pc of the Sun and their mean temperatures, turbulence, and velocity vectors. With the increasing number of sight lines now being analyzed, we find that temperatures and turbulent velocities have spatial variations within the LIC and other nearby clouds much larger than measurement uncertainties, and that these spatial variations appear to be randomly distributed and can be fit by Gaussians. The inhomogeneous length scale is less than 4,000 AU, a distance that the heliosphere will traverse in less than 600 years. The temperatures and turbulent velocities do not show significant trends with stellar distance or angle from the LIC center. If/when the Sun enters an inter-cloud medium, the physical properties of the future heliosphere will be very different from the present. For the heliosheath and the very local interstellar medium (VLISM) just outside of the heliopause, the total pressures are approximately equal to the gravitational pressure of overlying material in the Galaxy. The internal pressure in the LIC is far below that in the VLISM, but there is an uncertain ram pressure term produced by the flow of the LIC with respect to its environment.