搜索结果: 121-135 共查到“理学 COSMIC”相关记录249条 . 查询时间(0.046 秒)
Constraints on cosmic-ray propagation models from a global Bayesian analysis
astroparticle physics—diffusion—methods statistical—cosmic rays—ISM general—Galaxy: general
2010/11/9
Research in many areas of modern physics such as, e.g., indirect searches for dark matter and particle acceleration in SNR shocks, rely heavily on studies of cosmic rays (CRs) and associated diffuse e...
Observational Constraints on Interacting Model of New Agegraphic Dark Energy and Alleviation of Cosmic Age Problem
Interacting Model New Agegraphic Dark Energy Alleviation of Cosmic Age Problem
2010/12/21
Many dark energy models fail to pass the cosmic age test via the old quasar APM 08279+5255 at
redshift z = 3.91, even the CDM model and the holographic dark energy model are not exception.In this pa...
A central theme in cosmology is the perplexing fact that the Universe is undergoing
an accelerating expansion. The latter, one of the most important and challenging current
problems in cosmology, re...
Probing the course of cosmic expansion with a combination of observational data
cosmic expansion combination of observational data
2010/11/16
We study the cosmic expansion history by reconstructing the deceleration parameter q(z)
from the SDSS-II type Ia supernova sample (SNIa) with two different light curve fits (MLCS2k2
and SALT-II), th...
Examining the cosmic acceleration with the latest Union2 supernova data
latest Union2 supernova data
2010/11/16
In this Letter, by reconstructing the Om diagnostic and the deceleration parameter q from
the latest Union2 Type Ia supernova sample with and without the systematic error along with
the baryon acous...
p, He, and C to Fe cosmic-ray primary fluxes in diffusion models: Source and transport signatures on fluxes and ratios
Methods statistical – ISM cosmic rays
2010/11/10
Context. The source spectrum of cosmic rays is not well determined by diffusive shock acceleration models. The prop-agated fluxes of proton, helium, and heavier primary cosmic-ray species (up to Fe) a...
It is shown that Born-Infeld gravity –a high energy deformation of Einstein gravity– removes
the singularities of a cosmic string. The respective vacuum solution results to be free of conical singula...
Cosmic acceleration and the challenge of modifying gravity
Cosmic acceleration challenge of modifying gravity
2010/11/10
I briefly discuss the challenges presented by attempting to modify general relativity to obtain an explanation for the observed accelerated expansion of the universe. Foremost among these are the ques...
Constraints on the Cosmic-Ray Density Gradient beyond the Solar Circle from Fermi gamma-ray Observations of the Third Galactic Quadrant
cosmic rays – gamma rays ISM – ISM general
2010/11/10
We report an analysis of the interstellar-ray emission in the third Galactic quadrant measured
by the Fermi Large Area Telescope. The window encompassing the Galactic plane from longitude 210◦ ...
In this concise, albeit subjective review of structure formation, I shall introduce the cosmological standard model and its theoretical and observational underpinnings. I will focus on recent results ...
MHD Simulations of Parker Instability Undergoing Cosmic-Ray Diffusion: Effect of the Initial Equilibrium Conditions on Mixing
cosmic rays magnetohydrodynamics instability numerical simulation
2010/11/9
Parker instability arises from the presence of magnetic fields in a plasma such as the interstellar medium (ISM),wherein the magnetic buoyant pressure expels the gas and causes the gas to move along t...
Cosmic Jets
Cosmic Jets
2010/12/20
We discuss time-dependent gravitational elds that \accelerate" free test particles to the speed of light resulting in cosmic double-jet con gurations. It turns out that complete gravitational collaps...
How to use molecular clouds to study the propagation of cosmic rays in the Galaxy
cosmic rays:origin and propagation gamma rays molecular clouds
2010/11/12
Observations of molecular clouds in the gamma ray domain provide us with a tool to study the distribution of cosmic rays in the Galaxy. This is because cosmic rays can penetrate molecular clouds, unde...
Common origin for radio relics and halos: galaxy cluster-wide, homogeneous cosmic-ray distribution, and evolving magnetic fields
galaxies clusters general — galaxies clusters intracluster medium —X-rays galaxies: clusters
2010/11/10
Some galaxy clusters show diffuse radio emission in the form of peripheral relics (so
far attributed to primary, shock-(re)accelerated electrons) or central halos. Analysing
radio and X-ray data fro...
Probing the course of cosmic expansion with a combination of observational data
cosmic expansion combination of observational data
2010/12/20
We study the cosmic expansion history by reconstructing the deceleration parameter q(z)
from the SDSS-II type Ia supernova sample (SNIa) with two different light curve fits (MLCS2k2
and SALT-II), th...