RUI: Diffuse Emissions from Clusters and Superclusters of Galaxies

富星系团形成的Boughn模型预测，星系初始质量的10%-70%已被潮汐剥离，现在驻留在团内介质中。 来自剥离物质的恒星成分的可见光提供了这个质量的示踪剂，并且可以根据它被剥离的时代提供星团中暗物质的地图。 这个项目是观察几个星系团中弥漫的星系际光。 所有这些星系团的质量估计推导出星系速度色散使用维里定理，从X射线配置文件使用流体静力学平衡，并从观测背景星系的引力透镜。 漫射光的测量将提供一个额外的限制，在这些集群的质量分布，以及确认剥离假说。 此外，团内光的亮度强烈地制约着暗物质中矮星星的含量。 暗物质中低质量星星含量的问题是由于在银河系晕中发现低质量天体的微透镜效应而产生的。 以前对富星系团阿贝尔2029核心的观测揭示了星系团中心附近可能发生的潮汐剥离事件。 如果这种解释是正确的，那么就有一个极好的机会来研究星团演化中最重要的过程之一，并将通过对潮汐星云的高角分辨率观测来更详细地研究，在超星系团的星系际区域探测到的漫辐射不是光学的，而是光学的，来自恒星的光，而是来自热的电离气体的X射线发射。 一段时间以来，人们已经清楚，宇宙中重子物质的主要形式必须是电离气体。 如果超星系团中的这种气体处于维里温度，那么它应该发射韧致辐射X射线。 从局部超星系团的平面上探测到10 keV能量的弥散辐射，将对其性质进行研究。 这种气体与宇宙微波背景辐射的相互作用也被认为是宇宙微波背景辐射中的Sunayev-Zel'dovich（SZ）效应的来源。 预期的信号刚好在宇宙背景探测器（COBE）卫星DMR辐射计的灵敏度极限，但应该可以用新的MAP和普朗克卫星天文台探测到。 这种观测的可行性将通过模拟银河系对CMB辐射的污染和CMB中的随机波动来研究。 还参与了一个项目，利用RXTE X射线卫星探测附近沙普利超星系团的X射线发射，并将研究探测该星系团中SZ效应的前景。

AbstractAST 99-70761BoughnModels of the formation of rich clusters of galaxies predict that from 10 % to 70 % of the initial mass of the galaxies has been tidally stripped away and now resides in the intracluster medium. The optical light from the stellar component of the stripped matter provides a tracer of this mass and could, depending on the epoch at which it was stripped, provide a map of the dark matter in the cluster. This project is to observe the diffuse, intergalactic light in several clusters of galaxies. All of these clusters have mass estimates deduced from galaxy velocity dispersions using the virial theorem, from X-ray profiles using hydrostatic equilibrium, and from observations of gravitational lensing of background galaxies. The measurement of diffuse light will provide an additional constraint on the distribution of mass in these clusters as well as confirmation of the stripping hypothesis. In addition, the brightness of intracluster light strongly constrains the dwarf star content of the dark matter. The question of the low mass star content of dark matter has arisen because of the discovery of microlensing by low mass objects in the halo of the Milky Way. The previous observations of the core of the rich cluster Abell 2029 have revealed what could be a tidal stripping event near the cluster center. If this interpretation is correct, there is an excellent opportunity to study one of the most important processes in the evolution of clusters and it will be studied in more detail with high angular resolution observations of the tidal nebula, as well as with spectroscopic observations of the primary embedded galaxy and the nearby galaxies.The diffuse emission to be detected in the intergalactic regions of superclusters of galaxies is not the optical light from stars but rather the X-ray emission from hot, ionized gas. It has been clear for some time that the preponderance of baryonic matter in the universe must be in the form of ionized gas. If this gas in superclusters is at the virial temperature then it should emit bremsstrahlung X-rays. Diffuse 10 keV energy emission from the plane of the local supercluster has been detected its nature will be investigated. The interaction of this gas with the CMB is also expected to be the source of a Sunayev-Zel'dovich (SZ) effect in the Cosmic Microwave Background (CMB) radiation. The expected signal is just at the sensitivity limit of the Cosmic Background Explorer (COBE) satellite's DMR radiometers, but should be detectable with the new MAP and PLANCK satellite observatories. The feasibility of such observations will be investigated by modeling both Galactic contamination to the CMB radiation and the random fluctuations in the CMB. There is also involvement in a project to detect X-ray emission from the nearby Shapley supercluster using the RXTE X-ray satellite and the prospects for detecting the SZ effect in that cluster will be investigated.