Disparity among low first ionization potential elements

Author:

Heidrich-Meisner VerenaORCID,Berger Lars,Wimmer-Schweingruber Robert F.

Abstract

Context. The elemental composition of the solar wind differs from the solar photospheric composition. Elements with low first ionization potential (FIP) appear enhanced compared to O in the solar wind relative to the respective photospheric abundances. This so-called FIP effect is different in the slow solar wind and the coronal hole wind. However, under the same plasma conditions, for elements with similar FIPs such as Mg, Si, and Fe, comparable enhancements are expected. Aims. We scrutinize the assumption that the FIP effect is always similar for different low FIP elements, namely Mg, Si, and Fe. Methods. Here we investigate the dependency of the FIP effect of low FIP elements on the O7+/O6+ charge state ratio depending on time, that is the solar activity cycle, and solar wind type. In addition, we order the observed FIP ratios with respect to the O7+/O6+ charge state ratio into bins and analyze separately the respective distributions of the FIP ratio of Mg, Si, and Fe for each O7+/O6+ charge state ratio bin. Results. We observe that the FIP effect shows the same qualitative yearly behavior for Mg and Si, while Fe shows significant differences during the solar activity maximum and its declining phase. In each year, the FIP effect for Mg and Si always increases with increasing O7+/O6+ charge state ratio, but for high O7+/O6+ charge state ratios the FIP effect for Fe shows a qualitatively different behavior. During the years 2001–2006, instead of increasing with the O7+/O6+ charge state ratio, the Fe FIP ratio exhibits a broad peak or plateau. In addition, the FIP distribution per O7+/O6+ charge state bin is significantly broader for Fe than for Mg and Si. Conclusions. These observations support the conclusion that the elemental fractionation is only partly determined by FIP. In particular, the qualitative difference in behavior with increasing O7+/O6+ charge state ratio between Fe on the one hand and Mg and Si on the other hand is not yet well explained by models of fractionation.

Publisher

EDP Sciences

Subject

Space and Planetary Science,Astronomy and Astrophysics

Reference39 articles.

1. FIP BIAS EVOLUTION IN A DECAYING ACTIVE REGION

2. Benenson W., Harris J. W., Stöcker H., Lutz H., et al. 2006, Handbook of Physics (Berlin: Springer)

3. Berger L. 2008, PhD Thesis, Christian Albrechts Universität, Kiel, Ukraine

4. Determination of the abundance of aluminum in the solar wind with SOHO/CELIAS/MTOF

Cited by 5 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3