星系团阿贝尔1644（$\bar{z}=0.047$）以其显著的螺旋状X射线辐射而闻名。它以前被认为是一个双峰系统，包括子星系团A1644S和A1644N，每个子星系团都以一个巨大的椭圆星系为中心。在这项工作中，我们提出了一个全面的研究这个系统，包括新的弱透镜和动力学数据和分析，加上量身定制的流体动力学模拟。透镜和星系密度图显示了在X射线图像上看不到的北部结构。因此，我们将之前已知的北晕重新命名为A1644N1，新的北晕重新命名为A1644N2。我们的透镜数据表明，它们具有相当相似的质量：$M_{200}^{\rm N1}=0.90_{-0.85}^{+0.45} \times10^{14}$和$M_{200}^{\rm N2}=0.76_{-0.75}^{+0.37} \times10^{14}$ M $_\odot$，而南部结构是主要的：$M_{200}^{\rm S}=1.90_{-1.28}^{+0.89}\times 10^{14}$ M $_\odot$。基于观测数据的模拟，我们提出了一个方案，在该系统中显着的X射线特性是A1644 S和A1644 N2之间的碰撞发生在$\sim$ 1.6 Gyr前的结果。目前，这些系统在达到最大间隔后，应该正在前往一个新的相遇。
英文摘要：
The galaxy cluster Abell 1644 ($\bar{z}=0.047$) is known for its remarkable spiral-like X-ray emission. It was previously identified as a bimodal system, comprising the subclusters, A1644S and A1644N, each one centered on a giant elliptical galaxy. In this work, we present a comprehensive study of this system, including new weak-lensing and dynamical data and analysis plus a tailor-made hydrodynamical simulation. The lensing and galaxy density maps showed a structure in the North that could not be seen on the X-ray images. We, therefore, rename the previously known northern halo as A1644N1 and the new one as A1644N2. Our lensing data suggests that those have fairly similar masses: $M_{200}^{\rm N1}=0.90_{-0.85}^{+0.45} \times10^{14}$ and $M_{200}^{\rm N2}=0.76_{-0.75}^{+0.37} \times10^{14}$ M$_\odot$, whereas the southern structure is the main one: $M_{200}^{\rm S}=1.90_{-1.28}^{+0.89}\times 10^{14}$ M$_\odot$. Based on the simulations, fed by the observational data, we propose a scenario where the remarkable X-ray characteristics in the system are the result of a collision between A1644S and A1644N2 that happened $\sim$1.6 Gyr ago. Currently, those systems should be heading to a new encounter, after reaching their maximum separation.
The merger history of the complex cluster Abell 1758: a combined weak lensing and spectroscopic view
We present a weak-lensing and dynamical study of the complex cluster Abell 1758 (A1758, z = 0.278) supported by hydrodynamical simulations. This cluster is composed of two main structures, called A1758N and A1758S. The Northern structure is composed of A1758NW & A1758NE, with lensing determined masses of 7.90_{-1.55}^{+1.89} X 10^{14} M_ \odot and 5.49_{-1.33}^{+1.67} X 10^{14} M_ \odot , respectively. They show a remarkable feature: while in A1758NW there is a spatial agreement among weak lensing mass distribution, intracluster medium and its brightest cluster galaxy (BCG) in A1758NE the X-ra…
Weak-lensing Analysis of Intracluster Filaments in Abell 2744: Matched-filter Scans and Stepwise 2D Tracing
Yonsei University（延世大学）；California Institute of Technology（加州理工学院）；University of California, Davis（加州大学戴维斯分校）；INAF–Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）
Hubble Frontier Fields : A High-Precision Strong-Lensing Mass Model of the Massive Galaxy Cluster Abell 2744 using 180 Multiple Images
我们提出了一个高精度的星系团阿贝尔2744的质量模型，强引力透镜分析的基础上的\emph{Hubble Space Telescope Frontier Fields}（HFF）的成像数据，现在包括两个\emph{Advanced Camera for Surveys}和\emph{Wide-Field Camera 3}观测到的最终深度。利用可见光和近红外数据前所未有的深度，我们确定了34个新的多重成像星系，使总数达到61个，包括181个单独的透镜图像。在这个过程中，我们纠正以前的错误识别和位置的集群核心的北部的多个系统。使用\textsc{Lenstool}软件和新的多组图像，我们使用两个星系团规模的暗物质晕和星系团成员的星系团规模的晕来模拟星系团。我们的最佳拟合模型预测图像的位置与\emph{RMS}的误差为0.69 $\arcsec$，这构成了一个改进的几乎是一个因素的两个在以前的参数模型，这个集群。我们测量了200 kpc口径内的总投影质量（$2.162\pm 0.005$）$\times 10^{14}M_{\odot}$，从而继最近的HFF测量MACSJ 0416.1 -2403之后，第二次达到1级精度。重要的是，质量模型的更高质量转化为导出的放大因子的4倍的总体改进。%的高红移透镜背景星系。与我们以前的HFF引力透镜分析一起，这项工作表明，HFF数据能够对大质量星系…
Weak lensing and spectroscopic analysis of the nearby dissociative merging galaxy cluster Abell 3376
The galaxy cluster Abell~3376 is a nearby (z=0.046) dissociative merging cluster surrounded by two prominent radio relics and showing an X-ray comet-like morphology. The merger system is comprised of the subclusters A3376W & A3376E. Based on new deep multi-wavelength large-field images and published redshifts, we bring new insights about the history of this merger. Despite the difficulty of applying the weak lensing technique at such low redshift, we successfully recovered the mass distribution in the cluster field. Moreover, with the application of a two-body model, we have addressed the dyna…
The ALMA Frontier Fields Survey. VI. Lensing-corrected 1.1mm number counts in Abell 2744, MACSJ0416.1-2403, MACSJ1149.5+2223, Abell 370 and Abell S1063
本文利用 ALMA 对五个哈勃前沿场星系团的观测，通过统计透镜校正和蒙特卡洛模拟，推导出低至 0.01 mJy 的 1.1mm 计数，证实了计数平坦化趋势并支持其对应高红移红外光度函数拐点的解释。
The Grism Lens-Amplified Survey from Space (GLASS). IV. Mass reconstruction of the lensing cluster Abell 2744 from frontier field imaging and GLASS spectroscopy
Improved strong lensing modelling of galaxy clusters using the Fundamental Plane: Detailed mapping of the baryonic and dark matter mass distribution of Abell S1063
Improved strong lensing modelling of galaxy clusters using the Fundamental Plane: detailed mapping of the baryonic and dark matter mass distribution of Abell S1063
Stellar dynamics in the strong-lensing central galaxy of Abell 1201: A low stellar mass-to-light ratio, a large central compact mass, and a standard dark matter halo
On the correlation between globular clusters and the distribution of dark matter in galaxy clusters: the case of Abell 2744
Canadian Institute for Theoretical Astrophysics (CITA), University of Toronto（多伦多大学理论天体物理研究所 (CITA)）；Department of Physics & Astronomy, McMaster University（麦克马斯特大学物理与天文系）；Instituto Galego de Física de Altas Enerxías, Universidade de Santiago de Compostela（圣地亚哥-德孔波斯特拉大学加利西亚高能物理研究所）；Department of Statistical Sciences, University of Toronto（多伦多大学统计科学系）；David A. Dunlap Department of Astronomy & Astrophysics, University of Toronto（多伦多大学大卫·A·邓普克天文与天体物理学系）；Dunlap Institute for Astronomy & Astrophysics, University of Toronto（多伦多大学邓普克天文与天体物理研究所）；Data Sciences Institute, University of Toronto（多伦多大学数据科学研究院）
Chandra Lensing-cluster Ultradeep Extragalactic Survey (CLUES) I: A 2 Ms Point-Source Catalog of the Abell 2744 Field
Peking University（北京大学）；Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）；University of Michigan（密歇根大学）；Nanjing University（南京大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；Institute for Gravitation and the Cosmos, The Pennsylvania State University（宾夕法尼亚州立大学引力与宇宙学研究所）
