搜索结果: 1-15 共查到“天文学 radiation”相关记录41条 . 查询时间(0.502 秒)
We examine the cooling radiation from forming galaxies in hydrodynamic simulations of the LCDM model (cold dark matter with a cosmological constant), focusing on the Lyα line luminosities of high-reds...
Enrichment of the intergalactic medium by radiation pressure-driven dust efflux
intergalactic medium abundances
2014/12/26
The presence of metals in hot cluster gas and in Lyα absorbers, as well as the mass-metallicity relation of observed galaxies, suggest that galaxies lose a significant fraction of their metals to the ...
Transition Radiation from the Neutrino-Photon Interaction in Matter
Transition Radiation the Neutrino-Photon Interaction Matter
2012/2/23
We show that, because of their effective electromagnetic interaction in matter, transition radiation is emitted whenever neutrinos goes across the boundary between two media with different indices of ...
CMB radiation in an inhomogeneous spherical space
CMB radiation in an inhomogeneous spherical space
2011/10/20
We analyse the CMB radiation in spherical 3-spaces with non-trivial topology. The focus is put on an inhomogeneous space which possesses observer dependent CMB properties. The suppression of the CMB a...
Emission geometry, radiation pattern, and magnetic topology of the magnetar XTE J1810-197 in its quiescent state
pulsars: general – stars: neutron – X-rays: individual: XTE J1810− 197
2011/10/17
The return to the quiescent state of the Anomalous X-ray pulsar XTE J1810-197 following its 2003 outburst represents a unique opportunity to probe the surface emission properties of a magnetar. The qu...
Recent cosmological observations, including measurements of the CMB anisotropy and the primordial helium abundance, indicate the existence of an extra radiation component in the Universe beyond the st...
Photon noise limited radiation detection with lens-antenna coupled Microwave Kinetic Inductance Detectors
Photon noise limited radiation Microwave Kinetic Inductance Detectors
2011/10/13
Microwave Kinetic Inductance Detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here we demonstrate for the first time in the su...
X-rays and hard UV radiation From the First Galaxies: Ionization Bubbles and 21 cm Observations
stars: Population III. galaxies: high-redshift. (galaxies:) quasars: general. galaxies: star formation. cosmology: theory. (cosmology:) dark ages, reionization, rst stars
2011/10/9
The first stars and quasars are known sources of hard ionizing radiation in the first billion years of the Universe. We examine the joint effects of X-rays and hard UV radiation from such first-light ...
Helicity and dynamo action in magnetized stellar radiation zones
magnetohydrodynamics (MHD) – instabilities – stars: magnetic fi elds – stars: interiors
2011/10/8
Helicity and \alpha effect driven by the nonaxisymmetric Tayler instability of toroidal magnetic fields in stellar radiation zones are computed. In the linear approximation a purely toroidal field alw...
Coherent Cherenkov Radiation from Cosmic-Ray-Induced Air Showers
Coherent Cherenkov Radiation Cosmic-Ray-Induced
2011/9/27
Very energetic cosmic rays entering the atmosphere of the Earth will create a plasma cloud moving with almost the speed of light. The magnetic field of the Earth induces an electric current in this cl...
Radiation-driven winds of hot luminous stars. XVI. Expanding atmospheres of massive and very massive stars and the evolution of dense stellar clusters
Radiation mechanisms: general – Methods: numerical – Radiative transfer – early Universe – Stars: early-type – mass- loss – stellar winds – very massive stars – stellar evolution
2011/9/27
Context: Starbursts, and particularly their high-mass stars, play an essential role in the evolution of galaxies. The winds of massive stars not only significantly influence their surroundings, but th...
Extremal energy shifts of radiation from a ring near a rotating black hole
Extremal energy rotating black hole
2011/1/11
Radiation from a narrow circular ring shows a characteristic double-horn profile dominated by photons having energy around the maximum or minimum of the allowed range, i.e. near the extremal values of...
Extremal energy shifts of radiation from a ring near a rotating black hole
Extremal energy shifts radiation black hole
2011/1/11
Radiation from a narrow circular ring shows a characteristic double-horn profile dominated by photons having energy around the maximum or minimum of the allowed range, i.e. near the extremal values of...
Macroscopic Geo-Magnetic Radiation Model; Polarization effects and finite volume calculations
Macroscopic Geo-Magnetic Radiation Model Polarization effects finite volume calculations
2011/1/11
An ultra-high-energy cosmic ray (UHECR) colliding with the Earth's atmosphere gives rise to an Extensive Air Shower (EAS). Due to different charge separation mechanisms within the thin shower front co...
Macroscopic Model of Geomagnetic-Radiation from Air Showers, II
Macroscopic Model Geomagnetic-Radiation Air Showers, II
2011/1/11
The generic properties of the emission of coherent radiation from a moving charge distribution are discussed. The general structure of the charge and current distributions in an extensive air shower a...