用气体动力学模拟星系超星系团中的Sunyaev-Zeldovich效应：北冕事例
The Sunyaev-Zeldovich effect in superclusters of galaxies using gasdynamical simulations: the case of Corona Borealis
摘要：
[摘要]我们使用MareNostrum宇宙SPH模拟研究了与星系超星系团相关的热和动力学Sunyaev-Zel'dovich（SZ）效应。我们认为超星系团类似于北冕超星系团（CrB-SC）。本文的动机是在33 GHz的检测到一个强大的温度递减的CMB对这个超星系团的核心。VSA和MITO的多频观测表明，在这个冷点的光谱中存在热SZ效应分量，这将占总观测到的衰减量的大约25%。我们确定了9个地区包含超星系团类似CrB-SC，获得相关的SZ地图，并计算发现这种SZ信号所产生的超星系团内的热气体的概率。我们的研究结果表明，WHIM产生的热SZ效应远小于观察值。也不能将该区域的小星系团和星系群的贡献相加来解释SZ信号的振幅。当我们考虑到观测结果的实际后验分布时，WHIM可以引起像观测到的那样的热SZ信号的概率<1%，当包括小星系团和星系群的贡献时，上升到3.2%。如果模拟提供了一个合适的描述的气体物理，那么我们的结论是，热SZ组件的CrB点最有可能产生一个未知的星系团沿视线。模拟还表明，与超星系团相关的动力学SZ信号不能解释其余75%的CrB中观察到的冷点。
英文摘要：
[Abridged] We study the thermal and kinetic Sunyaev-Zel'dovich (SZ) effect associated with superclusters of galaxies using the MareNostrum Universe SPH simulation. We consider superclusters similar to the Corona Borealis Supercluster (CrB-SC). This paper is motivated by the detection at 33GHz of a strong temperature decrement in the CMB towards the core of this supercluster. Multifrequency observations with VSA and MITO suggest the existence of a thermal SZ effect component in the spectrum of this cold spot, which would account for roughly 25% of the total observed decrement. We identify nine regions containing superclusters similar to CrB-SC, obtain the associated SZ maps and calculate the probability of finding such SZ signals arising from hot gas within the supercluster. Our results show that WHIM produces a thermal SZ effect much smaller than the observed value. Neither can summing the contribution of small clusters and galaxy groups in the region explain the amplitude of the SZ signal. When we take into account the actual posterior distribution from the observations, the probability that WHIM can cause a thermal SZ signal like the one observed is <1%, rising up to a 3.2% when the contribution of small clusters and galaxy groups is included. If the simulations provide a suitable description of the gas physics, then we conclude that the thermal SZ component of the CrB spot most probably arises from an unknown galaxy cluster along the line of sight. The simulations also show that the kinetic SZ signal associated with the supercluster cannot provide an explanation for the remaining 75% of the observed cold spot in CrB.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
