搜索结果: 1-8 共查到“高能天体物理学 Origin”相关记录8条 . 查询时间(0.385 秒)
Constraints on the origin of ultra-high-energy cosmic rays from cosmogenic neutrinos and photons
Astroparticle physics Acceleration of particles Abundances Neutrinos Gamma-rays Relativistic processes
2011/10/11
We study the production of cosmogenic neutrinos and photons during the extragalactic propagation of ultra-high-energy cosmic rays (UHECRs). For a wide range of models in cosmological evolution of sour...
Quantum fluctuations in planar domain-wall space-times: A possible origin of primordial preferred direction
Quantum fluctuations planar domain-wall space-times possible origin primordial preferred direction
2011/10/18
We study the gravitational effects of a planar domain wall on quantum fluctuations of a massless scalar field during inflation. By obtaining an exact solution of the scalar field equation in de Sitter...
Origin of the Ultrahigh-Energy Cosmic Rays and their Spectral Break
Ultrahigh-Energy Cosmic Rays Spectral Break
2010/11/15
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 ...
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 ...
The Origin of Dust in the Early Universe: Probing the Star Formation History of Galaxies by their Dust Content
galaxies evolution high-redshift starburst - quasars individ-ual
2010/11/11
Two distinct scenarios for the origin of the ∼ 4 × 108 M⊙ of dust observed in the high-redshift (z = 6.4) quasar J1148+5251 have been proposed. The first assumes that this galaxy is much younger...
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...
On the Origin of Ultraviolet Emission and the Accretion Model of Low-luminosity AGNs
accretion accretion disks — black hole physics — galaxies active — quasars general — Ultraviolet general
2010/11/12
Low-luminosity active galactic nuclei (LLAGNs) are generally believed to be powered by an inner radiatively inefficient, advection-dominated accretion flow (ADAF), an outer truncated thin disk, and a ...
On the origin of variable gamma-ray emission from the Crab Nebula
ISM supernova remnants MHD shock waves gamma-rays theory radiation mechanisms non-thermal
2010/11/12
The oblique geometry of pulsar wind termination shock ensures that the Doppler beaming has a strong impact on the shock emission. We illustrate this using recent relativistic MHD simulations of the Cr...