From Cool to Ultracool: Investigating Magnetism and Rotation in the Smallest Stars and Ultra Cool Dwarfs

亚历杭德罗·努涅斯被授予数学和物理科学上升博士后研究奖学金（MPS-Ascend），在哥伦比亚大学进行研究和教育计划。Nunez博士计划利用地面和空间观测站的公共档案，并辅以研究期间收集的专门观测资料，对13个开放星星集群进行旋转和磁活动普查。基于这些观察，他计划研究活动对旋转的依赖性，特别关注超冷矮星，在不同年龄的疏散星团进行研究。 Nunez博士将指导参加哥伦比亚大学博士桥梁的参与者。程序. Nunez博士将比较不同的活动指标，以测试描述恒星大气磁加热的竞争理论。尽管几十年的理论和观测努力，一个准确的，定量的描述年龄旋转活动的关系仍然难以捉摸。他试图回答几个基本的理论问题。他打算量化旋转和磁活动对诸如核壳耦合程度和磁场几何形状等数量的依赖性。为了通往博士学位的桥梁。他的职责将包括跟踪参与者的进展，收集反馈，并组织活动，培养参与者的社区意识，帮助他们的专业发展。他将为参与者提供一致的、高质量的、针对具体领域的建议和指导。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。

Alejandro Nunez is awarded a Mathematical and Physical Sciences Ascending Postdoctoral Research Fellowship (MPS-Ascend) to conduct a program of research and education at Columbia University. Dr. Nunez plans a rotational and magnetic activity census for 13 open star clusters, using public archives of ground and space-based observatories, complemented with dedicated observations collected during the Fellowship. Based on these observations, he plans a study of the dependence of activity on rotation, paying particular attention to ultra-cool dwarfs, at the different ages of the open clusters to be studied. Dr. Nunez will mentor participants in the Columbia University Bridge to the Ph.D. program. Dr. Nunez will compare different activity indicators to test competing theories describing magnetic heating of stellar atmospheres. Despite several decades of theoretical and observational efforts, an accurate, quantitative description of the age-rotation-activity relation remains elusive. He seeks to answer several fundamental theoretical questions. He intends to quantify the dependence of rotation and magnetic activity on quantities such as the degree of core-envelope coupling and the magnetic field geometry. For the Bridge to Ph. D. program, his responsibilities will include tracking the progress of participants, gathering feedback, and by organizing activities that foster a sense of community among the participants and that help them in their professional development. He will provide consistent, high-quality, field-specific advising and mentoring to participants.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.