Mapping Matter in Strong Gravity: Spectral-Timing of Black Holes and Neutron Stars

阿比盖尔·史蒂文斯被授予NSF天文学和天体物理学奖学金，在密歇根州立大学和密歇根大学开展研究和教育计划。 史蒂文斯将研究黑洞和中子星与低质量恒星相互作用时发出的X射线，重点是被称为准周期振荡（QPO）的发射的快速变化。 史蒂文斯将研究X射线的能谱和时间在QPO期间如何变化。这是一个关于物质如何在黑洞和中子星附近表现的探测器，它将帮助天文学家更好地理解自然界中其他地方找不到的强大引力场和磁场。 除了她的研究，史蒂文斯将建立一个中学外展计划在兰辛公立学区。 在那里，她将开发和领导以太阳、太阳系、超大质量黑洞和星系为主题的基于活动的互动天文学课程。史蒂文斯将使用相位分辨光谱学来研究低质量X射线双星（LXMB）中不同类型的QPO和脉动，其中包含一个致密天体、一个低质量恒星伴星以及致密天体周围恒星物质的吸积盘。 她将使用在她的博士论文中开发的光谱计时技术，以及全面的物理模型，来比较黑洞中发射区域的几何形状与中子星中的几何形状，并确定LMXB在强引力状态下不断变化的内部配置。 这项工作将导致更好地了解强引力场，粘性天体物理等离子体和非常强的磁场。 史蒂文斯还将与她所在大学的外展设施合作，在当地中学课堂上进行天文学浓缩。和/或#8195;该奖项反映了NSF的法定使命，并被认为是值得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的支持。

Abigail Stevens is awarded an NSF Astronomy and Astrophysics Fellowship to carry out a program of research and education at Michigan State University and at the University of Michigan. Stevens will study the X-rays emitted when black holes and neutron stars interact with low-mass stars, focusing on very rapid changes in emission called quasi-periodic oscillations (QPOs). Stevens will study how the energy spectrum and timing of X-rays changes during QPOs. This is a probe of how matter behaves close to black holes and neutron stars, and it will help astronomers to better understand the strong gravitational and magnetic fields found nowhere else in nature. Alongside her research, Stevens will establish a middle school outreach program in the Lansing Public School District. There she will develop and lead activity-based interactive astronomy lessons on the topics of the Sun, the Solar System, and supermassive black holes and galaxies.Stevens will use phase-resolved spectroscopy of different types of QPOs and pulsations in low-mass X-ray binaries (LXMBs), which contain a compact object, a low-mass stellar companion, and an accretion disk of stellar material around the compact object. She will use a spectral-timing technique developed during her PhD thesis, as well as comprehensive physical models, to compare the geometry of the emitting region in black holes with that in neutron stars and determine the changing inner configuration of LMXBs in the strong-gravity regime. This work will lead to better understanding of intense gravitational fields, viscous astrophysical plasmas, and very strong magnetic fields. Stevens will also work with outreach facilities at her host universities to conduct astronomy enrichment in local area middle school classes. 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.