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

银河系的气体环星系介质是我们银河系形成的化石记录，也是未来星星形成的巨大物质库。目前只有5%的气体晕被绘制出来。Werk博士和她的团队将绘制温暖的电离晕气体的全部范围。这些观测将进一步加深我们对晕中气体的化学成分和流动的理解。沃克博士将扩大她在西雅图中央学院成功的社区大学转学计划，包括华盛顿州的另外五所大学。转学计划为学生提供指导，因为他们成功地过渡到华盛顿大学的4年STEM课程。Werk博士和她的团队将通过对晕星、遥远的类星体（QSO）、类星体和快速射电暴（FRB）的观测，绘制出温暖电离晕气体的完整范围。 电离CGM的金属丰度将使用40条瞄准线测量，这些瞄准线朝向银河系晕中的紫外线明亮恒星，这些恒星非常接近一颗已知的脉冲星。低速、电离、扩展的MWCGM（Milky Way gas circumgalactic medium）的特征是从对投影中邻近的远距离类星体的相同测量值中减去对晕蓝水平分支星的不饱和Si IV和C IV吸收剖面的测量值。线轮廓分析将量化的非热过程的MWCGM能量的贡献。将分析大约150对类星体和恒星，包括银河系低纬度的新的紫外线明亮类星体目标。该奖项反映了NSF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.