The properties of a solar wind stream are determined by its source region and by transport effects. Independently of the solar wind type, the solar wind measured in situ is always affected by both. We consider the proton-proton collisional age as an ordering parameter for the solar wind at 1AU and explore its relation to the solar wind classification scheme developed by Xu & Borovsky (2015). We use this to show that explicit magnetic field information is not required for this solar wind classification. Based on the observation that the three basic solar wind types from this categorization cover different regimes in terms of proton-proton collisional age $a_{col,p-p}$ , we propose a simplified solar wind classification scheme that is only based on the proton-proton collisional age. The resulting so-called PAC solar wind classifier is an alternative to the full Xu & Borovsky (2015) solar wind classification scheme and leads to a classification that is very similar to the full Xu & Borovsky (2015) scheme. The solar wind is well ordered by the proton-proton collisional age. This implies underlying intrinsic relationships between the plasma properties, in particular, proton temperature and magnetic field strength in each plasma regime. We argue that sector-reversal plasma is a combination of particularly slow and dense solar wind and most stream interaction boundaries. Most solar wind parameters (e.g., the magnetic field strength, B, and the oxygen charge state ratio $n_{O^{7+}}$ /$n_{O^{6+}}$) change with the solar activity cycle. Thus, all solar wind categorization schemes based on threshold values need to be adapted to the solar activity cycle as well.
Deceleration of Alpha Particles in the Solar Wind by Instabilities and the Rotational Force: Implications for Heating, Azimuthal Flow, and the Parker Spiral Magnetic Field
Observations of high and low Fe charge states in individual solar wind streams with coronal-hole origin
起源于冕洞的太阳风比较容易理解，其特点是与所谓的慢速太阳风相比，密度和平均电荷状态较低。除波扰动外，冕洞太阳风的平均性质是大致恒定的。在这个案例研究中，我们专注于观测的太阳风离子成分谱仪（SWICS）的高级成分探测器（ACE）的单个流的冕洞太阳风，说明虽然O和C的电荷状态是低的冕洞风，铁电荷分布是更多变的。特别是，\markmeold{we illustrate that the Fe charge states in coronal-hole solar wind are frequently as high as in slow solar wind. We selected individual coronal-hole solar wind}流基于它们的碰撞年龄以及它们各自的O和C电荷态，并分析了它们的Fe电荷态分布。此外，结合简单的弹道反映射和势场源表面模型，高和低Fe电荷状态的流之间的转换被映射回光球。2004年和2006年的相对频率高，低铁电荷态流进行了比较。我们发现了几个其他典型的冕洞流，包括铁的电荷状态或高或低，在缓慢的太阳风。在2006年的八个这样的过渡被映射回赤道冕洞，要么是孤立的或连接到北冕洞。到目前为止，识别与过渡相关的冠状结构的尝试还没有定论。
Evidence for Solar-Cycle Modulation of the Alpha-to-Proton Temperature Ratio in Solar Wind
Physical Research Laboratory (PRL)（物理研究实验室）；Indian Institute of Technology (IIT), Gandhinagar（甘地纳加尔印度理工学院）；Department of Physics and Astronomy, University of Iowa（爱荷华大学物理与天文系）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；The Catholic University of America（美利坚天主教大学）；Department of Geosciences, Tel Aviv University（特拉维夫大学地球科学系）
Effect of Binary Fraction on Horizontal Branch Morphology under Tidally Enhanced Stellar Wind
潮汐增强的星风可能通过增强双星演化过程中主星的质量损失来影响球状星团（GC）中的水平支（HB）形态。Lei等人（2013a，2013 b）详细研究了这种风对HB形态的影响，他们的结果表明，双星是GC中可能的第二参数（2P）候选者。双星分数是潮汐增强星风模式中一个非常重要的事实。在本文中，我们研究了影响HB形态的二元分数通过去除金属丰度和年龄的影响。五个不同的二进制分数（即，10%、15%、20%、30%和50%）。在不同的金属丰度和年龄下，获得了具有不同二元分数的合成HB形貌。我们发现，由于金属丰度和年龄的影响很大，二进制分数对HB形态的影响可能被这两个参数掩盖。然而，当去除金属丰度和年龄的影响时，HB形貌随着二元分数的增加而变得更蓝的趋势被清楚地呈现。此外，我们将我们的结果与Milone et al.（2012）的观察结果进行了比较。我们的结果是一致的，以及在富金属和贫金属GC的观察。对于具有中等金属丰度的GC，当年龄对HB形态的影响被删除时，HB形态随着二元分数的增加而变得更蓝的微弱趋势在GC的所有区域中呈现，这与我们在该金属丰度范围内获得的结果一致。
