Related papers: The Arrowhead Mini-Supercluster of Galaxies

We considered kinematic and virial parameters of a sample of galaxy triplets from the Local Supercluster (LS). The galaxies were selected from the LEDA database, and their radial velocities are no more than 3100 km/s. The sample contains…

We have mapped the large-scale structure of the Serpens cloud core using moderately optically thick (13CO(1--0) and CS(2--1)) and optically thin tracers (C18O(1--0), C34S(2--1), and N2H+(1--0)), using the 16-element focal plane array…

We study the infrared (K_s band) properties of clusters of galaxies in the Ursa Major supercluster using data from 2MASS (Two-Micron All-Sky Survey) and SDSS (Sloan Digital Sky Survey). We identified three large filaments with mean…

Galaxy superclusters, the largest galaxy structures in the cosmic web, are formed due to the gravitational collapse (although they are not usually gravitationally bound). Their geometrical properties can shed light on the structure…

According to the latest evidence, the Universe is entering an era of exponential expansion, where gravitationally bound structures will get disconnected from each other, forming isolated `island universes'. In this scenario, we present a…

We present 1"-resolution ALMA observations of the circumnuclear disk (CND) and the environment around SgrA*. The images unveil the presence of small spatial scale CO (J=3-2) molecular "cloudlets" within the central pc of the Milky Way,…

We present the result of searching for clusters of galaxies based on weak gravitational lensing analysis of the $\sim 160$~deg$^2$ area surveyed by Hyper Suprime-Cam (HSC) as a Subaru Strategic Program. HSC is a new prime focus optical…

Using the initial peculiar velocity field, we analytically study the hierarchical formation of gravitationally bound objects. The field is smoothed over a scale that corresponds to the mass of a given class of objects. Through the…

We present the spectroscopic confirmation of a $z=2.45$ proto-cluster. Its member galaxies lie within a radius of 1.4Mpc (physical) on the sky and within $\Delta v \pm 700$km/s along the line of sight. We estimate an overdensity of 10,…

We present 3D kinematic observations of stars within the central 0.5 pc of the Milky Way nuclear star cluster using adaptive optics imaging and spectroscopy from the Keck telescopes. Recent observations have shown that the cluster has a…

The cosmic star-formation rate density, molecular gas density and the AGN activity of the Universe peak at z~ 2-3, showing the Universe is most active at this epoch. The nature of the galaxies at these redshifts and their properties as a…

The discovery of the large-scale structure has transformed our view of galaxy formation and evolution. Filaments of the cosmic web provide key environments that channel the growth of structures. Guided by predictions from cosmological…

[OIII] lambda 5007AA emission lines of 16 intracluster planetary nebulae candidates in the Coma cluster were detected with a Multi-Slit Imaging Spectroscopy (MSIS) technique using FOCAS on the Subaru telescope. The identification of these…

The Arcturus stream is an over-density of stars in velocity space and its origin has been much debated recently without any clear conclusion. Resolving the nature of the Arcturus stream can provide clues to the formation history of the…

We quantify the structure of a very large number of Galactic open clusters and look for evidence of mass segregation for the most massive stars in the clusters. We characterise the structure and mass segregation ratios of 1276 clusters in…

We present a simple, self-consistent model to predict the maximum masses of giant molecular clouds (GMCs), stellar clusters and high-redshift clumps as a function of the galactic environment. Recent works have proposed that these maximum…

The hot X-ray emitting plasma in galaxy clusters is predicted to have turbulent motions which can contribute around ten percent of the cluster's central energy density. We report deep Chandra X-ray Observatory observations of the Coma…

We report the discovery of a compact supercluster structure at z=0.9. The structure comprises three optically-selected clusters, all of which are detected in X-rays and spectroscopically confirmed to lie at the same redshift. The Chandra…

The Coma cluster is the richest and most compact of the nearby clusters, yet there is growing evidence that its formation is still on-going. With a new multi-slit imaging spectroscopy technique pioneered at the 8.2 m Subaru telescope and…

Protoclusters represent the most extreme environments in the very early Universe. They form from large-scale dark matter overdensities, harbouring an overabundance of galaxies fed by large gas reservoirs. Their early and accelerated…