Supplementary material for PhD thesis "SPH simulations of X-ray binary systems" -3/4: sph view 3d

This dataset comprises the files contained on a CD-ROM which was attached to the thesis when it was submitted in 2006. It was uploaded to ORDO in 2024 for preservation purposes. For more information, please refer to the thesis SPH simulations of X-ray binary systems via ORO.Thesis abstractIn low mass X-ray binaries a neutron star or a black hole accretes from a low mass companion star via an accretion disc. The physics of accretion discs in these systems is currently an area of vigorous international research activity. In particular the advent of supercomputing has allowed quantitative numerical work on the dynamics of such systems. The numerical simulations are becoming increasingly able to reproduce observed phenomena, and the interplay between simulation and observation is refining the picture derived from analytical work on these systems. Consequently this PhD exploits the synergy between observation and simulation. We present two/three-dimensional smoothed particle hydrodynamics (SPH) simulations of a number of binary systems, such as XTE J1118+480, and reveal complex accretion discs that are continuously varying in shape, kinematics and dissipation. The stream-disc impact region and disc spiral density waves are prominent sources of energy dissipation. For extreme mass ratios the dissipated energy is modulated on the superhump period. We generate synthetic trailed spectrograms that reveal two distinct `S-wave' features, produced by the stream gas and the disc gas at the stream-disc impact shock. These S-waves are non-sinusoidal, and evolve with disc precession phase. We also describe three-dimensional SPH calculations of warped accretion discs in X-ray binary systems. Geometrically thin, optically thick accretion discs are illuminated by a central radiation source. This illumination exerts a non-axisymmetric radiation pressure on the surface of the disc resulting in a torque that acts on the disc to induce a twist or warp. Initially planar discs are shown to be unstable to warping driven by the radiation torque and in general the warps also precess in a retrograde direction relative to the orbital flow. We simulate a number of X-ray binary systems which have different mass ratios using a number of different luminosities for each. Models for X-ray binary systems such as Her X-1 and SS 433 are able to reproduce their observed long period photometric modulations.

本数据集收录了2006年提交论文时所附带的CD-ROM中包含的文件。为保存目的，该数据集于2024年上传至ORDO。如需更多信息，请参阅通过ORO进行的X射线双星系统SPH模拟的论文摘要。在低质量X射线双星系统中，中子星或黑洞通过吸积盘从低质量伴星吸积物质。此类系统吸积盘的物理机制是目前国际研究的热点领域。特别是，超级计算的出现使得对这类系统动力学进行定量数值研究成为可能。数值模拟正日益能够再现观测现象，而模拟与观测之间的相互作用正在完善对这些系统分析工作得出的图像。因此，本博士论文充分利用了观测与模拟之间的协同效应。我们展示了多个双星系统（如XTE J1118+480）的二维/三维平滑粒子流体动力学（SPH）模拟，揭示了形状、运动学和耗散持续变化的复杂吸积盘。射流-吸积盘相互作用区域和吸积盘螺旋密度波是能量耗散的显著来源。对于极端质量比，耗散的能量在超周期上呈现调制。我们生成了合成尾迹光谱图，揭示了由射流气体和吸积盘气体在射流-吸积盘相互作用冲击处产生的两个明显的S波特征。这些S波非正弦波，并随吸积盘进动相位演化。此外，我们还描述了X射线双星系统中扭曲吸积盘的三维SPH计算。几何上薄、光学上厚的吸积盘被中央辐射源照亮。这种照明在吸积盘表面施加非轴对称辐射压力，从而产生作用于吸积盘的扭矩，导致吸积盘产生扭曲或变形。初始平面盘在辐射扭矩驱动的扭曲作用下表现出不稳定性，并且通常扭曲相对于轨道流动方向逆时针进动。我们使用每个系统的不同亮度模拟了多个具有不同质量比的X射线双星系统。如Her X-1和SS 433等X射线双星系统的模型能够再现其观测到的长周期光变振幅。