RUI: Time-Resolved Observations of Classical and Dwarf Novae

新星、矮新星、类似新星的恒星都被认为是成对的恒星，在这些恒星中，主序恒星正在缓慢膨胀，并将其部分物质转移到轨道上的“白矮星”上。来自第一颗恒星的新鲜氢气的加热导致了白矮星表面的热核反应，导致了我们观察到的一大类新星类型的快速发光。许多天文学家试图了解，这些系统中的每一个是否都是处于不同进化阶段的同一类型的天体，还是它们是根本不同类型的天体。在这项为期两年的研究中，首席研究员(PI)和一名学生将监测过去发生过新星喷发的十几颗双星，以检查周期和其他轨道特征，从而改进对这些恒星的质量和半径的估计。预计这将使已知这些基本参数的恒星数量增加一倍，并使人们能够更好地估计它们的周期分布。PI预计，这项研究将有助于解决新星是否经历了快速的质量转移事件，随后两颗恒星之间在更长的时间内几乎没有交换。这个问题的解决将有助于确定新星、矮新星和类似新星的系统是否是在不同演化阶段观察到的相同系统。这是一个由美国国家科学基金会本科生研究计划赞助的奖项，预计将为PI机构的研究生和本科生的科学指导做出贡献。

Novae, dwarf novae, novae-like stars are all thought to be pairs of stars in which a "main sequence" star is slowly expanding and transferring some of its matter onto an orbiting "white dwarf." The heating of fresh hydrogen from the first star results in thermonuclear reactions on the white dwarf's surface, leading to a vast class of rapid brightenings we observe as nova-type stars. Many astronomers are trying to understand whether each of these systems is the same type of object in a different stage of evolution or whether they are fundamentally different types of objects. In this two-year study the Principal Investigator (PI) and a student will monitor a dozen binary stars that have under- gone nova eruptions in the past to examine the periods and other orbital characteristics that would lead to improved estimates of these stars' masses and radii. This is expected to double the number of stars for which these fundamental parameters are known and to permit a better estimate to be made of the distribution of their periods. The PI anticipates that this study will contribute to resolving whether nova undergo rapid mass transfer events followed by little exchanges between the two stars over longer times. A resolution of this issue will help determine whether novae, dwarf novae, and nova-like systems are the same system merely observed in different stages of evolution. This is an award under the auspices of the NSF's Research for Undergraduate Institutions program and is expected to contribute to the scientific instruction of graduate and undergraduate students at the PI's institution.