相关论文: Back-in-time dynamics of the cluster IE 0657-56 (t…
We present semi-analytical constraint on the amount of dark matter in the merging bullet galaxy cluster using the classical Local Group timing arguments. We consider particle orbits in potential models which fit the lensing data. {\it…
The Bullet Cluster (1E0657-56) is well-known as providing visual evidence of dark matter but it is potentially incompatible with the standard $\Lambda$CDM cosmology due to the high relative velocity of the two colliding clusters. Previous…
To quantify how rare the bullet-cluster-like high-velocity merging systems are in the standard LCDM cosmology, we use a large-volume 27 (Gpc/h)^3 MICE simulation to calculate the distribution of infall velocities of subclusters around…
Deep Chandra exposures of the hot galaxy cluster 1E0657-56 have revealed that the cluster is observed shortly after the first core-passage of a massive infalling subcluster, which is preceded by a prominent bow shock with Mach number M~3.…
We present high resolution N-body/SPH simulations of the interacting cluster 1E0657-56. The main and the sub-cluster are modeled using extended cuspy LCDM dark matter halos and isothermal beta-profiles for the collisional component. The hot…
The Bullet Cluster (1E0657-56) merger is of exceptional interest for testing the standard cold-dark-matter plus cosmological constant cosmological model, and for investigating the possible existence of a long- or short-range "fifth-force"…
A key uncertainty in interpreting observations of bimodal merging galaxy clusters is the unknown angle between the subcluster separation vector and the plane of the sky. We present a new method for constraining this key parameter. We find…
Shock waves driven in the intergalactic medium during the merging of galaxy clusters have been observed in X-ray imaging and spectroscopy. Fluid motions inferred from the shock strength and morphology can be compared to the cold dark matter…
We present a new strong lensing mass reconstruction of the Bullet cluster (1E 0657-56) at z=0.296, based on WFC3 and ACS HST imaging and VLT/FORS2 spectroscopy. The strong lensing constraints underwent substantial revision compared to…
We present a phenomenological model of the dynamics of buoyant bubbles in the atmosphere of a cluster of galaxies. The derived equations describe velocity, size, mass, temperature and density of the buoyant bubbles as functions of time…
We present the results of a new spectroscopic and photometric survey of the hot X-ray cluster 1E0657-56, at z=0.296. We determine the presence of a low velocity dispersion subcluster, which is offset from the main cluster position by 0.7…
It has been recently shown that the observed morphological properties of the Bullet Cluster can be accurately reproduced in hydrodynamical simulations only when the infall pairwise velocity V_{c} of the system exceeds 3000km/s (or at least…
We use hydrodynamical/N-body simulations to interpret the newly discovered Bullet-cluster-like merging cluster, ZwCl 0008.8+5215 (ZwCl 0008 hereafter), where a dramatic collision is apparent from multi-wavelength observations. We have been…
Mergers between galaxy clusters are an important stage in the formation of the large-scale structure of the Universe. Some of the mergers show a spectacular bow shock that formed as a result of recent passage of a smaller cluster through a…
Merging galaxy clusters have become one of the most important probes of dark matter, providing evidence for dark matter over modified gravity and even constraints on the dark matter self-interaction cross-section. To properly constrain the…
We show that the fast moving component of the "bullet cluster" (1E0657-56) can induce potentially resolvable redshift differences between multiply-lensed images of background galaxies. The moving cluster effect can be expressed as the…
We model the electrons/positrons produced by dark matter annihilations in the colliding galaxy cluster system 1E0657-56 (the bullet cluster). These charged particles, confined by the Magnetic field, clearly trace the path of the bullet,…
We compare new maps of the hot gas, dark matter, and galaxies for 1E0657-56, a cluster with a rare, high-velocity merger occurring nearly in the plane of the sky. The X-ray observations reveal a bullet-like gas subcluster just exiting the…
Since the discovery of the "bullet cluster" several similar cases have been uncovered suggesting relative velocities well beyond the tail of high speed collisions predicted by the concordance LCDM model. However, quantifying such…
The unique properties of dark matter are revealed during collisions between clusters of galaxies, like the bullet cluster (1E 0657-56) and baby bullet (MACSJ0025-12). These systems provide evidence for an additional, invisible mass in the…