POWRE: Accretion to Rotating Magnetized Stars

摘要-罗曼诺娃AST 9973366 A全职研究计划在康奈尔大学的理论，模拟和分析的观测等离子体吸积旋转磁化恒星将进行。许多吸积星，例如致密星和原恒星，都是旋转的，并被推断出具有显着的内禀磁场。这些系统的关键观测方面，例如，星星是向上旋转还是向下旋转，取决于吸积物质与星星磁层的相互作用。旋转磁化星星的吸积问题已经引起天文学家的兴趣超过四分之一个世纪，但它仍然只有一个定性的，有争议的解决方案。这个问题的困难来自于它是一个多维磁流体动力学（MHD）流动问题。这方面的进展需要二维或三维的模拟，现在在计算机上是可行的。 将与康奈尔大学的教员合作，研究旋转磁化恒星吸积的二维和三维建模问题。两个主要的研究方向计划：第一是进行系统的模拟研究，并获得磁盘和邦迪型球形吸积旋转磁化恒星的星星的不同旋转速率，不同的恒星磁矩，不同的吸积率的标度关系。在这项研究中，已经开发和测试的2D（轴对称）MHD代码将被使用。 该代码将用于确定流入或流出的角动量的星星。 研究的第二个方向将是创建一个并行版本的2D代码用于康奈尔超级计算机，并开发3D代码用于调查3D方面的吸积：交换不稳定性和吸积到倾斜的旋转器。模拟结果将应用于不同的具体物体：原恒星、激变变星、X射线天体、QPO和瞬态X射线源。.该项目涉及与来自俄罗斯的两位数字MHD专业专家的国际合作，他们将访问康奈尔大学。预计研究结果不仅会引起天体物理学专家的广泛兴趣，而且会引起天体物理学和行星科学专家的广泛兴趣。新版本的代码将记录在案，并提供给其他感兴趣的科学家。 该奖项由国际计划司，天文科学司和数学和物理科学局多学科活动办公室的资金支持。

Abstract - Romanova AST 9973366A full-time research program at Cornell University on the theory, simulations, and analysis of observations of plasma accretion to rotating magnetized stars will be carried out. Many accreting stars, for example, compact stars and protostars, are rotating and are deduced to have significant intrinsic magnetic fields. Key observational aspects of these systems, for example, whether the star spins-up or spins-down, are determined by the interaction of accreting matter with the magnetosphere of the star. This problem of accretion to a rotating magnetized star has been of interest to -astronomers for more than a quarter of century, but it still has only a qualitative, controversial solution. The difficulty of this problem arises from the fact that it is a multidimensional magnetohydrodynamic (MHD) flow problem. Progress on it requires two or three- dimensional simulations which are now feasible on computers. Research on the problem of 2D and 3D modeling of accretion to rotating magnetized stars will be carried out in collaboration with faculty members at Cornell University. Two main directions of research are planned: The first is to perform a systematic simulation study and obtain scaling relations for both disk and Bondi-type spherical accretion to rotating magnetized stars for different rotation rates of the star, different stellar magnetic moments, and different accretion rates. In this study an already developed and tested 2D (axisymmetric) MHD code will be used. The code will be used to determine the inflow or outflow of angular momentum to the star. A second direction of the research will be the creation of a parallel version of the 2D code for use on the Cornell Supercomputer, and the development of 3D code for investigation of 3D aspects of accretion: interchange instability and accretion to an inclined rotator. The results of the simulations will be applied to different specific objects: protostars, cataclysmic variables, X-ray pulsars, QPOs, and transient X-ray sources. . The project involves the international collaboration with two professional specialists in numerical MHD from Russia, who will visit Cornell. The results of the research are expected to have broad general interest for specialists not only in astrophysics, but also in geophysics and planetary sciences. The new version of the code will be documented and made available to other interested scientists. This award is supported by funds from the Division of International Programs, the Division of Astronomical Sciences, and the Office of Multidisciplinary Activities in the Directorate of Mathematical and Physical Sciences.