论文标题
与$λ$ cdm背景相互作用的暗物质聚集
Clustering of dark matter in interacting tachyon dark energy with $Λ$CDM background
论文作者
论文摘要
标量场暗能量的非典型描述之一是Tachyon。目前的工作致力于研究与共同耦合的Tachyon场暗能量模型中暗物质过度密度的动力学。该型号调节以模仿背景级别的$λ$ CDM宇宙学。深度密度的半分析球形塌陷模型被采用以研究非线性进化。研究了非最小耦合在能量预算中对暗物质聚类的影响。据观察，在非最小耦合的情况下，物质过度密度的生长速率更高。在相互作用的情况下，倒塌时的临界密度被抑制。此外，使用压力机和索尔特摩森光环质量函数研究了暗物质光环或星系簇的数量计数。当允许相互作用时，观察到暗物质光环的数量抑制。在本模型中进行了群集数量计数和$λ$ CDM的比较。与$λ$ CDM相比，允许交互的本模型产生的星系簇数量要低得多，但是没有相互作用，群集数量计数略高于$λ$ CDM群集计数。
One of the non-canonical descriptions of scalar field dark energy is the tachyon. The present work is devoted to study the dynamics of dark matter overdensity in a conformally coupled tachyon field dark energy model. The model is tuned to mimic the $Λ$CDM cosmology at background level. The semi-analytic spherical collapse model of dark matter overdensity is adopted to study the nonlinear evolution. The effects of non-minimal coupling in the energy budget on the clustering of dark matter is investigated. It is observed that the growth rate of matter overdensity is higher in presence of the non-minimal coupling. The critical density at collapse is suppressed in case of interaction. Further the number counts of dark matter halos or galaxy clusters along redshift are studied using the Press-Schechter and Sheth- Tormen halo mass functions. Suppression in the number of dark matter halos is observed when the interaction is allowed. A comparison of cluster number count in the present model and $Λ$CDM is carried out. The present model allowing the interaction produces much lower number of galaxy clusters compared to $Λ$CDM, but without interaction the cluster number count is slightly higher than $Λ$CDM cluster count.
