Numerical study of evolution of proto-galaxies and proto-clusters for observational cosmology in the next generation.

本项目的主要目标是开发一个在定量研究原星系和原星系团演化过程中不可或缺的宇宙流体动力学程序，并建立一个能够以分析和补充的方式处理上述问题的理论模型。具体地说，我们的研究结果概括如下：(1)我们编写了一个基于光滑粒子流体力学方法的宇宙学程序，该程序可以适当地考虑气体辐射过程。(2)我们推导了引力约束天体的形成和破坏速率的解析表达式。结合非线性球面模型，我们计算了单个星系团的热韧致辐射能谱，并对星系团的宇宙X射线背景通量和光谱进行了理论预测。(3)尽管最近在处女座CLU…中发现的造父变星更多的星际星系为哈勃常数H_0-80公里/秒/MPC提供了额外的支持，其他距离指示器提出了一个相对较低的H_0-50公里/秒/MPC的值。为了探索局部决定的H0与其全球平均值有显著不同的观点，我们考虑了嵌入在空间平坦宇宙中的局部开放宇宙的模型。我们在局部宇宙中找到了哈勃常数的下限和年龄上限的解析表达式，并计算了旋转坍缩的超新星核的引力波。比较各种角动量分布的结果，我们发现LIGO可以探测到这样的信号，前提是我们的星系中发生了旋转的超新星。另一方面，我们发展了一个新的广义相对论流体力学程序，其中假定了球对称，并采用了全隐式格式。我们认为这段代码对研究延迟机制是有用的。较少

The prinicpal goal of the present project is to develop a cosmological hydrodynamic code which is indispensible in quantitatively examining the evolution of proto-galaxies and proto-clusters, and to construct a theoretical model which can approach the above problem in a analytical and complementary manner. To be more specific, the results of our research are summarized as follows :(1) We have written up a cosmological code which is based on the smoothed particle hydrodynamic method and can properly take into account the gas-radiative processes.(2) We have derived analytical expressions for formation and destruction rates of gravitationally bound objects. Combining with the nonlinear spherical model, we computed the thermal bremsstrahlung spectrum emitted from individual proto-clusters of galaxies, and then made theoretical predictions of the cosmic X-ray background flux and spectrum due to the clusters of galaxies.(3) While the recent discovery of the Cepheid variables in the Virgo clu … More ster galaxies puts additional support for the Hubble constant H_0 - 80km/sec/Mpc, a relatively lower value H_0 - 50km/sec/Mpc is suggested by other distance indicators. In order to explore an idea that locally determined H_0 is significantly different from its global average, we considered a model of a locally open universe embedded in the spatially flat universe. We found analytic expressions for the lower limit on the global Hubble constant, and the upper limit on the age of the universe with a given value for the Hubble constant in the local universe.We calculated the gravitational wave form from a rotationally collapsing supernova core. Comparing the results for various angular momentum distributions, we found that LIGO can detect such a signal provided that a rotating supernova occurs in our galaxy. On the other hand, we have developed a new general relativistic hydrodynamics code in which spherical symmetry is assumed and fully implicit scheme is adopted. We think this code is useful to study the delayd mechanism. Less