Astronomy Reports ( IF 1 ) Pub Date : 2020-11-17 , DOI: 10.1134/s1063772920120045 M. Demianski , A. Doroshkevich , T. Larchenkova , S. Pilipenko
Abstract
A comparison of the virial parameters of galaxies and galaxy clusters (radius, density, and entropy function) in a wide range of masses, \({{10}^{6}} \leqslant {{M}_{{{\text{vir}}}}}{\text{/}}{{M}_{ \odot }} \leqslant {{10}^{{14}}}\), shows that these parameters are correlated and depend on the virial mass of an object in a regular way. For the observed galaxies and galaxy clusters the available estimates of virial parameters are quite close to each other and the values of reduced virial density Gρ are concentrated in a shallow interval \(0.5 \leqslant {{G}_{\rho }}{\text{/}}\langle {{G}_{\rho }}\rangle \leqslant 2\) around its mean value. This “virial” paradox sharpen when compared with simulations, in which the number of such objects is very small, and for the majority of dark matter halos these densities are ~50–100 times smaller. Our theoretical analysis shows possible reasons for this discrepancy of observations and simulations, pointing out its connection with the spectrum of cosmological perturbations. After some refinement, the considered data can be used to constrain models of cosmological inflation. A number of accompanying questions is discussed.
中文翻译:
观测和数值模型中的星系
摘要
\({{10} ^ {6}} \ leqslant {{M} _ {{{\ text}}在较大质量范围内的星系和星系簇的病毒参数比较(半径,密度和熵函数){vir}}}}} {\ text {/}} {{M} _ {\ odot}} \ leqslant {{10} ^ {{14}}} \),表明这些参数是相关的,并取决于物体的病毒质量。所观察到的星系和星系团维里参数的现有的估计是相当接近彼此并且降低维里密度的值G ^ ρ都集中在一个浅间隔\(0.5 \ leqslant {{G} _ {\ RHO}} { \ text {/}} \ langle {{G} _ {\ rho}} \ rangle \ leqslant 2 \)在其平均值附近。与仿真相比,这种“病毒性”悖论更加尖锐,在仿真中,此类物体的数量非常小,并且对于大多数暗物质光环而言,这些密度要小50-100倍。我们的理论分析显示了观测和模拟差异的可能原因,并指出了它与宇宙扰动谱的联系。经过一些改进后,可以将考虑的数据用于约束宇宙膨胀模型。讨论了许多附带的问题。