CAREER: The Disk/Halo Link: Synthesizing Gaseous Tracer Samples in the Milky Way

银河系的气态环星系介质是我们银河系形成的化石记录，也是未来恒星形成的巨大物质储存库。目前这个气体晕的体积只有5%被绘制出来。沃克博士和她的团队将绘制出热电离光晕气体的全部范围。这些观测将进一步加深我们对光晕中化学成分和气体流动的理解。沃克博士将把她在西雅图中央学院成功的社区大学转学项目扩展到华盛顿州的另外五所大学。转学计划为学生提供指导，帮助他们成功过渡到华盛顿大学的四年制STEM项目。此外，该项目还为天文学本科生提供全面的项目支持，提供以学生为中心的研究机会和学习计划。Werk和她的团队将通过对晕星、遥远的准恒星天体（qso）、脉冲星和快速射电暴（frb）的观测，绘制出热电离晕气体的全部范围。电离后的CGM的金属丰度将通过40条瞄准银河晕中靠近已知脉冲星的紫外线明亮恒星的视线来测量。低速、电离、扩展的MWCGM（银河系气态环星系介质）的特征是，从对投影附近遥远qso的相同测量中减去对晕蓝水平分支星的不饱和Si IV和C IV吸收剖面的测量。线剖面分析将量化非热过程对MWCGM能量学的贡献。大约150对QSO和恒星将被分析，包括在银河系低纬度的新的紫外QSO目标。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The Milky Way’s gaseous circumgalactic medium is a fossil record of the formation of our Galaxy and a large reservoir of material for future star formation. Only 5% of the volume of this gaseous halo is currently mapped. Dr. Werk and her team will map the full extent of the warm ionized halo gas. The observations will further our understanding of the chemical composition and flow of gas in the halo. Dr. Werk will expand her successful community college transfer program at Seattle Central College to include five additional colleges across Washington State. The transfer program provides mentorship for students as they successfully transition to a 4-year STEM program at the University of Washington. In addition, the program provides full programmatic support to astronomy undergraduates with student-focused research opportunities and learning initiatives.Dr. Werk and her team will map the full extent of the warm ionized halo gas using observations of halo stars, distant quasi-stellar objects (QSOs), pulsars, and fast radio bursts (FRBs). The metallicity of the ionized CGM will be measured using 40 lines of sight towards UV-bright stars in the Galactic halo that lie within close proximity to a known pulsar. The low velocity, ionized, extended MWCGM (Milky Way gaseous circumgalactic medium) will be characterized by subtracting measurements of unsaturated Si IV and C IV absorption profiles toward halo blue horizontal branch stars from the same measurements toward distant QSOs nearby in projection. A line profile analysis will quantify the contribution of non-thermal processes to the MWCGM energetics. Approximately 150 pairs of QSOs and stars will be analyzed including new UV-bright QSO targets at low Galactic latitudes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.