Recent studies in different types of galaxies reveal that the product of the central density and the core radius ($ρ_cr_c$) is a constant. However, some empirical studies involving galaxy clusters suggest that the product $ρ_cr_c$ depends weakly on the total dark halo mass. In this article, we re-analyse the hot gas data from 106 clusters and obtain a surprisingly tight scaling relation: $ρ_c \propto r_c^{-1.46 \pm 0.16}$. This result generally agrees with the claims that $ρ_cr_c$ is not a constant for all scales of structure. Moreover, this relation does not support the velocity-dependent cross section of dark matter if the core formation is due to the self-interaction of dark matter.
We investigate how a property of a galaxy correlates most tightly with a property of its host dark matter halo, using state-of-the-art hydrodynamical simulations of galaxy formation EAGLE, Illustris, and IllustrisTNG. Unlike most of the previous work, our analyses focus on all types of galaxies, including both central and satellite galaxies. We find that the stellar mass of a galaxy at the epoch of the peak circular velocity with an evolution correction gives the tightest such correlation to the peak circular velocity $V_{\rm peak}$ of the galaxy's underling dark matter halo. The evolution of …
Many studies point out that there exists some tight correlations between dark matter and baryonic matter at different radii in galaxies. However, similar tight correlations can only be found in galaxy clusters for large radii. Here we report extremely tight correlations between the gravitational mass $M_{\rm grav}$ and hot gas mass $M_{\rm gas}$ in galaxy clusters at the hot gas core radius $r_c$ and at $2r_c$ (i.e. $M_{\rm grav}(r_c)$ vs $M_{\rm gas}(r_c)$ and $M_{\rm grav}(2r_c)$ vs $M_{\rm gas}(2r_c)$). By using the X-ray data of 64 large galaxy clusters with different sizes and masses, we …
We report a tight Hubble constant constraint $67.78^{+1.21}_{-1.86}$ km s$^{-1}$ Mpc$^{-1}$ (2.26\% precision) derived from galaxy redshift surveys. We combine the BAO measurements from 6dFGS, the SDSS DR7 main galaxies, the BOSS DR12 galaxies, and eBOSS DR14 quasars, and also apply the tomographic Alcock-Paczynski (AP) method to the BOSS DR12 galaxies, to place constraints on $H_0$ in the spatially flat $Λ$CDM framework. Our result is fully consistent with the CMB constraints from Planck, but in $2.58σ$ tension with local measurements of Riess et al. 2016. Compared with the BAO alone constrai…
Conventionally, in galaxy surveys, cosmological constraints on the growth and expansion history of the universe have been obtained from the measurements of redshift-space distortions and baryon acoustic oscillations embedded in the large-scale galaxy density field. In this paper, we study how well one can improve the cosmological constraints from the combination of the galaxy density field with velocity and tidal fields, which are observed via the kinetic Sunyaev-Zel'dovich (kSZ) and galaxy intrinsic alignment (IA) effects, respectively. For illustration, we consider the deep galaxy survey by …
SZ scaling relations have been used to test the self-similar prediction for massive galaxy clusters, but little attention has been given to individual galaxy groups. We investigate the scaling relations of galaxy groups and clusters near the North Ecliptic Pole using X-ray and SZ observations. This region of the sky is where both the ROSAT and Planck satellites achieved their deepest observations, permitting the investigation of lower mass systems. Our sample consists of 62 X-ray detected groups and clusters, spanning a mass range of $10^{13.4}M_{\odot}<~M_{500}<10^{15}M_{\odot}$ and redshifts…
We test two methods, including one that is newly proposed in this work, for correcting for the effects of chameleon $f(R)$ gravity on the scaling relations between the galaxy cluster mass and four observable proxies. Using the first suite of cosmological simulations that simultaneously incorporate both full physics of galaxy formation and Hu-Sawicki $f(R)$ gravity, we find that these rescaling methods work with a very high accuracy for the gas temperature, the Compton $Y$-parameter of the Sunyaev-Zel'dovich (SZ) effect and the X-ray analogue of the $Y$-parameter. This allows the scaling relati…
In this paper, we propose a new test to the cosmic distance duality relation (CDDR), $D_L=D_A(1+z)^2$, where $D_L$ and $D_A$ are the luminosity and angular diameter distances, respectively. The data used correspond to 61 Type Ia Supernova luminosity distances and $Y_{SZE}-Y_X$ measurements of 61 galaxy clusters obtained by the {\it Planck} mission and the deep XMM-Newton X-ray data, where $Y_{SZE}$ is the integrated comptonization parameter obtained via Sunyaev-Zel'dovich effect observations and $Y_X$ is the X-ray counterpart. More precisely, we use the $Y_{SZE}D_{A}^{2}/C_{XSZE}Y_X$ scaling-r…
As the end products of the hierarchical process of cosmic structure formation, galaxy clusters present some predictable properties, like those mostly driven by gravity, and some others, more affected by astrophysical dissipative processes, that can be recovered from observations and that show remarkable "universal" behaviour once rescaled by halo mass and redshift. However, a consistent picture that links these universal radial profiles and the integrated values of the thermodynamical quantities of the intracluster medium, also quantifying the deviations from the standard self-similar gravity-…
A review of elliptical and disc galaxy structure, and modern scaling laws
一个世纪前，在1911年和1913年，普卢默和雷诺兹提出了他们的模型来描述恒星在“星云”中的径向分布。本文回顾了自那时以来的进展，提供了一个历史的观点和当代审查的恒星结构的隆起，光盘和椭圆星系。星系核的量化，如中央质量赤字和过剩的核光，加上暗物质晕和cD星系信封的结构，进行了讨论。与旋涡星系有关的问题，包括尘埃，膨胀盘比，无球星系，酒吧和识别的pseudobulges也进行了审查。一系列现代尺度关系，涉及大小，光度，表面亮度和恒星浓度，其中许多是弯曲的。这些“红移零”关系不仅量化了今天宇宙中星系的行为和性质，而且是星系演化研究的现代基准，无论是基于观测，N体模拟还是半分析模型。例如，最近发现的一些1.5 < z < 2.5的致密椭圆星系可能是现代盘星系的凸起。
We present a new set of galaxy scaling relations for the relative mass content of atomic gas, molecular gas and stars. Such relations are driven by disc gravitational instability, and originate from the low galaxy-to-galaxy variance of Toomre's $Q$ stability parameter. We test such relations using more than 100 galaxies, from massive spirals to dwarf irregulars, thus spanning several orders of magnitude in stellar mass ($M_{\star}\approx10^{6\mbox{-}11}\,\mbox{M}_{\odot}$) and atomic gas mass ($M_{\mathrm{HI}}\approx10^{7\mbox{-}10.5}\,\mbox{M}_{\odot}$). Such tests demonstrate (i) that our sc…
Uncertainty in the mass-observable scaling relations is currently the limiting factor for galaxy cluster based cosmology. Weak gravitational lensing can provide a direct mass calibration and reduce the mass uncertainty. We present new ground-based weak lensing observations of 19 South Pole Telescope (SPT) selected clusters at redshifts $0.29 \leq z \leq 0.61$ and combine them with previously reported space-based observations of 13 galaxy clusters at redshifts $0.576 \leq z \leq 1.132$ to constrain the cluster mass scaling relations with the Sunyaev-Zel'dovich effect (SZE), the cluster gas mass…
In $Λ$CDM cosmology, to first order, galaxies form out of the cooling of baryons within the virial radius of their dark matter halo. The fractions of mass and angular momentum retained in the baryonic and stellar components of disc galaxies put strong constraints on our understanding of galaxy formation. In this work, we derive the fraction of angular momentum retained in the stellar component of spirals, $f_j$, the global star formation efficiency $f_M$, and the ratio of the asymptotic circular velocity ($V_{\rm flat}$) to the virial velocity $f_V$, and their scatter, by fitting simultaneousl…
The connection between galaxies and their dark matter haloes is often described with the Stellar-to-Halo Mass relation (SHMR). Satellite galaxies in clusters have been shown to follow a SHMR distinct from central galaxies because of the environmental processes that they are subject to. In addition, the variety of accretion histories leads to an important scatter in this relation, even more for satellites than for central galaxies. In this work, we use the hydrodynamical simulation IllustrisTNG to study the scatter in the satellite galaxy SHMR, and extract the parameters that can best allow to …
AMiBA: Sunyaev-Zel'dovich effect derived properties and scaling relations of massive galaxy clusters
在86-102 GHz波段观测到6个大质量星系团的Sunyaev-Zel'dovich效应（SZE），红移为0.091 \leq z \leq 0.322。T. Lee Array for Microwave Background Anisotropy（AMiBA）微波背景各向异性天线阵本文改进了一种基于等温β模型的迭代方法，从AMiBA SZE数据中导出了电子温度T_e、总质量M_t、气体质量M_g和r_2500内的积分康普顿Y。本文还考虑了非等温通用温度剖面（UTP）β模型。这些结果与其它观测结果符合得很好。我们还研究了由于我们所采用的方法中所作的假设，这些纯SZ推导的T_e，M_t，M_g和Y之间的嵌入标度关系。我们的研究结果表明，集群属性可能是可测量的SZE观测。然而，建立在纯SZE方法的假设偏差的标度关系估计的结果，需要进一步研究。
