相关论文: High Velocity Star Formation in the LMC
Context: Supernova 1987A (SN1987A) exploded in the Large Magellanic Cloud (LMC). Its proximity and rapid evolution makes it a unique case study of the early phases in the development of a supernova remnant. One particular aspect of interest…
We analyzed the largest Small Magellanic Cloud (SMC) cluster sample (32) with proper motions and radial velocity measurements, from which we obtained their space velocity components. By adopting as a reference the recent best-fitted…
The processes leading to the birth of low-mass stars such as our Sun have been well studied, but the formation of high-mass (> 8 x Sun's mass) stars has heretofore remained poorly understood. Recent observational studies suggest that…
The Nuclear Stellar Disk has been a highly active star-forming region in the Milky Way for approximately the last 30 million years. Despite hosting prominent clusters like Arches, Quintuplet, and Nuclear Stellar, their combined mass is less…
We present the peculiar in-plane velocities derived from the LAMOST red clump stars. From the variations of the in-plane velocity with the Galactocentric radius for the young and old red clump stars, we are able to identify two types of…
Interferometric observations of the W33A massive star-formation region, performed with the Submillimeter Array (SMA) and the Very Large Array (VLA) at resolutions from 5 arcsec (0.1 pc) to 0.5 arcsec (0.01 pc) are presented. Our three main…
We present a detailed analysis of the kinematics of 112 stars that mostly comprise the high velocity S-cluster and orbit the super massive black hole SgrA* at the center of the Milky Way. For 39 of them orbital elements are known, for the…
The disk galaxy simulated using our chemo-dynamical galaxy formation code, GCD+, is shown to have a thick disk component. This is evidenced by the velocity dispersion versus age relation for solar neighbourhood stars, which clearly shows an…
Nuclear star clusters (NSCs) are located at the photometric and dynamical centers of the majority of galaxies. They are among the densest star clusters in the Universe. The NSC in the Milky Way is the only object of this class that can be…
The galaxy cluster 1E 0657-56 has a bullet-like subcluster that is moving away from the centre of the main cluster at high speed. Markevitch et al. (2004) recently estimated a relative velocity of V_bullet = 4500 +1100/-800 km/s, based on…
We study the velocity distribution of Milky Way disk stars in a kiloparsec-sized region around the Sun, based on ~ 2 million M-type stars from DR7 of SDSS, which have newly re-calibrated absolute proper motions from combining SDSS positions…
Star formation occurs in molecular gas. In previous studies, the structure of the molecular gas has been studied in terms of molecular clouds, but has been overlooked beyond the cloud scale. We present an observational study of the…
The recent re-evaulation of the peculiar velocity field outside the Local Supercluster (Dekel et al. 1999, ApJ 522) has permitted a re-examination of the origins of the peculiar velocity field within the Local Supercluster using the Mark…
Ground-based UBV photometry of two fields in the northern disk of the LMC are presented. A distance modulus of (m-M)_0 = 18.41 +/- 0.04 and an extinction of A_V = 0.30 +/- 0.05 has been calculated for these fields. The measurable star…
We report far-infrared and submillimeter observations of Supernova 1987A, the star that exploded on February 23, 1987 in the Large Magellanic Cloud, a galaxy located 160,000 lightyears away. The observations reveal the presence of a…
Stars within 0.1 pc of the supermassive black hole Sgr A* at the Galactic centre are expected to encounter a cluster of stellar-mass black holes (BHs) that have segregated to that region. Some of these stars will scatter off an orbiting BH…
We have determined chemical abundances and radial velocities for stars in the field of the zeta Sculptoris cluster. We find that the cluster metal deficiency previously found from UBV photometry is too high; the cluster overall metallicity,…
We report results on the radial velocity dispersion profile built out to the outskirts of NGC 4147, a Milky Way globular cluster with detected strong tidal tails. The cluster was chosen to probe, from an observational point of view, recent…
Hypervelocity stars are intriguing rare objects traveling at speeds large enough to be unbound from the Milky Way. Several mechanisms have been proposed for producing them, including the interaction of the Galaxy's super-massive black hole…
We obtain Keck HIRES spectroscopy of HVS5, one of the fastest unbound stars in the Milky Way halo. We show that HVS5 is a 3.62 +- 0.11 Msun main sequence B star at a distance of 50 +- 5 kpc. The difference between its age and its flight…