搜索结果: 1-15 共查到“天体物理学 dwarf”相关记录52条 . 查询时间(0.058 秒)
Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA)have discovered that a dim, cool dwarf star is generating a surprisingly powerful magnetic field, one that rivals the most...
Dark matter is called "dark" for a good reason. Although they outweigh particles of regular matter by more than a factor of 5, particles of dark matter are elusive. Their existence is inferred by thei...
The Search for High-Mass X-ray Binaries in the Phoenix Dwarf Galaxy
High-Mass X-ray Binaries Phoenix Dwarf Galaxy
2012/2/23
We report on the first X-ray images of the Phoenix dwarf galaxy, taken with \emph{XMM-Newton} in July 2009. This local group dwarf galaxy shares similarities with the Small Magellanic Cloud (SMC) incl...
Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars. IV. Two bulge populations
Gravitational lensing: micro—Galaxy: bulge —Galaxy: formation —Galaxy: evolution —Stars: abundances
2011/10/20
Based on high-resolution (R~42000 to 48000) and high signal-to-noise (S/N~50 to 150) spectra obtained with UVES/VLT, we present detailed elemental abundances (O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn...
Substellar Objects in Nearby Young Clusters (SONYC) II: The Brown Dwarf Population of Rho Ophiuchi
Substellar Objects Nearby Young Clusters
2011/1/11
SONYC - Substellar Objects in Nearby Young Clusters - is a survey program to investigate the frequency and properties of brown dwarfs down to masses below the Deuterium burning limit in nearby star fo...
An abundance study of red-giant-branch stars in the Hercules dwarf spheroidal galaxy
red-giant-branch stars the Hercules dwarf spheroidal galaxy
2011/1/11
Using high-resolution spectroscopy, we provide a determination of [Fe/H] and [Ca/H] for confirmed red-giant branch member stars of the Hercules dwarf spheroidal galaxy. Based on this we explore the ag...
Spectroscopic observations of a sample of dwarf spirals galaxies. I.Oxygen abundances
Spectroscopic observations dwarf spirals galaxies
2011/1/13
The oxygen abundances for four dwarf spiral galaxies have been determined using long-slit spectroscopy. The abundances of these galaxies have not previously reported in the literature. Several HII reg...
The central slope of dark matter cores in dwarf galaxies: Simulations vs. THINGS
Galaxies dark matter halos – galaxies cosmological N-body+SPH simulations –galaxies kinematics and dynamics
2010/11/15
We make a direct comparison of the derived dark matter (DM) distributions between hydrody-
namical simulations of dwarf galaxies assuming a CDM cosmology and the observed dwarf galaxies sample from ...
The orbital and superhump periods of the dwarf nova HS 0417+7445 in Camelopardalis
bital and superhump periods Camelopardalis
2010/11/11
We present the 2005–2010 outburst history of the SUUMa-type dwarf HS 0417+7445,along with a detailed analysis of extensive time-series photometry obtained in March 2008 during the second recorded supe...
Dark and luminous matter in THINGS dwarf galaxies
Galaxies dark matter – galaxies kinematics and dynamics – galaxies
2010/11/10
We present mass models for the dark matter component of seven dwarf galaxies taken from “The
Hi Nearby Galaxy Survey” (THINGS) and compare these with those from numerical Cold Dark
Matter (CDM) s...
The First Ultra-Cool Brown Dwarf Discovered by the Wide-field Infrared Survey Explorer
(stars:) brown dwarfs (Galaxy:)solar neighborhood infrared
2010/11/12
We report the discovery of the first new ultra-cool brown dwarf found with the Wide-field Infrared Survey Explorer (WISE). The object’s preliminary designation is WISEPC J045853.90+643451.
Spectroscopic observations of a sample of dwarf spiral galaxies. II- Abundance gradients
dwarf spiral galaxies Abundance gradients
2010/11/10
The oxygen gradient of four dS galaxies has been determined using abundances for several
Hii regions determined with four different methods. The gradient slopes of the three non-barred
galaxies in t...
The evolution of dwarf galaxies in the Coma supercluster
galaxies clusters general galaxies clusters individual Coma galaxies dwarf
2010/11/10
We employ spectroscopic and photometric data from SDSS DR7, in a 500 square degree
region, to understand the evolution of dwarf (M+2
Formation and evolution of dwarf early-type galaxies in the Virgo cluster I. Internal kinematics
Galaxies clusters individual Virgo Galaxies dwarf Galaxies elliptical and lenticular cD Galaxies
2010/11/12
We present new medium resolution kinematic data for a sample of 21 dwarf early-type galaxies (dEs) mainly in the Virgo cluster,obtained with the WHT and INT telescopes at the Roque de los Muchachos Ob...
A white dwarf companion to the relativistic pulsar PSR J1141-6545
methods photometry – binaries close – pulsars general – stars neutron white dwarfs – individual PSRJ1141− 6545
2010/11/10
Pulsars with compact companions in close eccentric orbits are unique laboratories for testing general relativity and alternative theories of gravity. Moreover, they are excellent targets for future gr...