CAREER: The Early History of Galaxy Disk Formation

机构：华盛顿大学PI: Dalcanton， Julianne华盛顿大学的Julianne Dalcanton博士将利用她的CAREER奖来研究星系盘的形成。盘状星系形成的理论模型在解释盘状星系的许多基本特征方面取得了巨大的成功。Tully-Fisher关系、指数表面亮度曲线和盘状星系的旋转曲线都可以通过旋转气体云的简单球形坍缩模型来重现。然而，最近发现所有的薄盘星系都嵌入了一个额外的厚盘成分，这表明现有的图像太简单了。要么这个无处不在的厚盘成分捕捉了星系最初坍缩的一个独特阶段，要么它追踪了星系早期分层构建的过程（现有模型中没有这个阶段）。有了这个奖项，Dalcanton博士将提供关键的测量和必要的理论基础，将厚盘的创造纳入盘状星系形成的模型。通过测量大量厚盘样本的运动学、年龄和金属丰度，她将能够清楚地区分厚盘形成和盘状星系早期演化的几种情况。她还将执行一个系统的模拟和分析计算程序，以得出先前未被探索的厚盘人口的宇宙学含义。除了培训下一代科学家之外，Dalcanton博士还将设计并执行一个新颖的项目，在中学女生从科学、数学和技术领域开始流失之前，捕捉并加强她们对科学的兴趣。该方案将侧重于同时向女孩和她们的母亲伸出援手，帮助在家庭中培养一种“积极的科学”文化，并增加有科学倾向的年轻妇女从她们最有影响力的女性榜样那里获得的支持。这个项目是她目前在一家致力于培养青春期前女孩对科学和技术兴趣的非营利组织的董事会工作的产物。

Proposal ID: AST-0238683 Institution: University of Washington PI: Dalcanton, Julianne Dr. Julianne Dalcanton of the University of Washington will use her CAREER award to study the formation of galactic disks. Theoretical models of disk formation have had substantial success in explaining many of the basic features of disk galaxies. The Tully-Fisher relation, the exponential surface brightness profiles, and the rotation curves of disk galaxies all can be reproduced by models of a simple spherical collapse of a rotating gas cloud. However, the recent discovery that all thin disk galaxies are embedded within an additional thick disk component suggests that the existing picture is too simple. Either this pervasive thick disk component captures a distinct phase in the initial collapse of the galaxy, or it tracks the early hierarchical build-up of the galaxy (a phase absent from existing models). With this award, Dr. Dalcanton will provide the critical measurements and the theoretical foundations necessary for incorporating the creation of thick disks into models of disk galaxy formation. By measuring the kinematics, ages, and metallicities of a large sample of thick disks, she will be able to cleanly distinguish among several scenarios for the formation of thick disks and the early evolution of disk galaxies. She will also carry out a systematic program of simulations and analytic calculations to derive the cosmological implications of the previously unexplored thick disk population. In addition to her work in training the next generation of scientists, Dr. Dalcanton will design and execute a novel program to capture and reinforce the scientific interest of middle school girls, before their attrition from scientific, mathematical, and technological fields begins. The program will focus on outreach to the girls and their mothers simultaneously, to help foster a "science positive "culture within the home, and to increase the support that scientifically inclined young women receive from their most influential female role model. This project is an outgrowth of her current work on the Board of Directors of a non-profit organization devoted to fostering the interest of pre-teen girls in science and technology.