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Three Types Of Extreme-Energy Space Particles May Have Unified Origin（图）
Three Types Extreme-Energy Space Particles Unified Origin
2018/2/1
One of the biggest mysteries in astroparticle physics has been the origins of ultrahigh-energy cosmic rays, very high-energy neutrinos, and high-energy gamma rays. Now, a new theoretical model reveals...
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 Origin of the Primordial Fluctuation Spectrum and its Statistics
Quantum Origin Primordial Fluctuation Spectrum Statistics
2011/10/9
The account of the origin of cosmic structure, as provided by the standard inflationary paradigm, is not fully satisfactory, as has been argued in Perez et al 2006. The central point of that work is t...
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...
The Atlas3D project - X. On the origin of the molecular and ionised gas in early-type galaxies
Atlas3D project - X origin of the molecular ionised gas early-type galaxies
2011/8/24
We make use of interferometric CO and HI observations, and optical integral-field spectroscopy to probe the origin of the molecular and ionised interstellar medium (ISM) in local early-type galaxies (...
Statistical mechanics of collisionless orbits. I. Origin of central cusps in dark-matter halos
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Statistical Mechanics (cond-mat.stat-mech)
2010/12/23
We present an equilibrium statistical mechanical theory of collisionless self-gravitational systems with isotropic velocity distributions.
Homochirality through Photon-Induced Melting of RNA/DNA: the Thermodynamic Dissipation Theory of the Origin of Life
Homochirality Photon-Induced Melting RNA/DNA
2011/1/13
The homochirality of the molecules of life has been a vexing problem with no generally accepted solution to date. Since a racemic mixture of chiral nucleotides frustrates the extension and replication...
The Absence of Cold Dust and the Mineralogy and Origin of the Warm Dust Encircling BD +20 307
Cold Dust the Mineralogy the Warm Dust Encircling
2011/1/13
Spitzer Space Telescope photometry and spectroscopy of BD +20 307 show that all of the dust around this remarkable Gyr-old spectroscopic binary arises within 1 AU. No additional cold dust is needed to...
The origin of the Broad Line Region in Active Galactic Nuclei
the Broad Line Active Galactic Nuclei
2011/1/13
Although broad emission lines are the most reliable signature of the nuclear activity of a galaxy and the location of the emitting material is well measured by the reverberation method, the physical ...
Galactic cirrus emission at far-infrared wavelengths affects many extragalactic observations. Separating this emission from that associated with extragalactic objects is both important and difficult. ...
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 ...
A geometric solution to the coincidence problem, and the size of the landscape as the origin of hierarchy
coincidence problem size origin of hierarchy
2010/11/16
Without assuming necessary conditions for observers such as galaxies or entropy production, we
show that the causal patch measure predicts the coincidence of vacuum energy and present matter
density...
Origin and Dynamical Evolution of Neptune Trojans - II: Long Term Evolution
Kuiper Belt celestial mechanics minor planets asteroids – Solar system
2010/11/10
Following our earlier work studying the formation of the Neptunian Trojan population during the
planet’s migration, we present results examining the eventual fate of the Trojan clouds produced in tha...
Origin and Dynamics of the Mutually Inclined Orbits of Upsilon Andromedae c and d
Origin Dynamics Mutually Inclined Orbits
2010/11/12
We evaluate the orbital evolution and several plausible origins scenarios for the mutually inclined orbits of υ And c and d. These two planets have orbital ele-ments that oscillate with large amplitud...
The Origin of [OII] Emission in Recently Quenched AGN Hosts
galaxies active — galaxies clusters general — galaxies evolution X-rays galaxies
2010/11/11
We have employed emission-line diagnostics derived from DEIMOS and NIRSPEC spectroscopy to
determine the origin of the [OII] emission line observed in six AGN hosts at z 0.9. These galaxies are a s...