相关论文: Variations of paleointensity in the Paleogene

An Earth-like planetary magnetic field has been widely invoked as a requirement for habitability as it purportedly mitigates the fluxes of ionizing radiation reaching the surface and the escape of neutrals and ions from the atmosphere.…

Observations of $\gamma$-ray from blazars suggest the presence of magnetic fields in the intergalactic medium, which may require a primordial origin. Intense enough primordial magnetic fields can arise from theories of dynamical electroweak…

This letter describes a new phenomenon on the Parker Solar Probe of recurring plasma density enhancements that have $\Delta$n/n ~10% and that occur at a repetition rate of ~5 Hz. They were observed sporadically for about five hours between…

The magnetospheres of the outer planets exhibit turbulent phenomena in an environment which is qualitatively different compared to the solar wind or the interstellar medium. The key differences are the finite sizes of the magnetospheres…

Energy injection into the early universe can induce turbulent motions of the primordial plasma, which in turn act as a source for gravitational radiation. Earlier work computed the amplitude and characteristic frequency of the relic…

Terrestrial planets have been found orbiting Sun-like stars with extremely short periods --- some as short as 4 hours. These "ultra-short-period planets" or "hot Earths" are so strongly irradiated that any initial H/He atmosphere has…

A dispersion equation, which describes the interaction of low density electron beam with a degenerate electron quantum plasma, is derived and examined for some interesting cases. In addition to the instabilities similar to those for…

We report on the use of $^{69,71}$Ga nuclear magnetic resonance to probe spin dynamics in the rare-earth kagom\'{e} system Pr$_3$Ga$_5$SiO$_{14}$. We find that the spin-lattice relaxation rate $^{69}1/T_1$ exhibits a maximum around 30 K,…

We present an extensive study of the time dependence of the magnetization in a polycrystalline and low temperature charge ordered La0.5Ca0.5MnO3 sample. After application and removal of a 5 T magnetic field, a systematic variation of the…

We present a combined observational and theoretical analysis to investigate the nature of plasma turbulence at kinetic scales in the Earth's magnetosheath. In the first decade of the kinetic range, just below the ion gyroscale, the…

(abridged) A detailed examination of the evolution of stochastic magnetic fields between high cosmic temperatures and the present epoch is presented. A simple analytical model matching the results of the 3D MHD simulations allows for the…

The cosmic-ray intensity record from Belgrade muon detectors in the period 2002-2004 is subjected to power spectra analysis. Statistically significant peaks are found in datasets from both ground and underground (25 m w.e.) detectors. The…

Plasma in the earth's magnetosphere is subjected to compression during geomagnetically active periods and relaxation in subsequent quiet times. Repeated compression and relaxation is the origin of much of the plasma dynamics and…

We study the interaction of intense ultrashort laser pulses with cryogenic He jets using 2d/3v relativistic Particle-in-Cell simulations (XOOPIC). Of particular interest are laser intensities $(10^{15}-10^{20})$ W/cm$^2$, pulse lengths $\le…

The Matuyama-Brunhes reversal of Earth's magnetic dipole field took place 0.78 Ma ago, and detailed temporally resolved paleomagnetic data are available for this period. A geomagnetic reversal is expected to impact the cosmic ray flux,…

We report on magnetic field emergences covering significant areas of exploding granules. The balloon-borne mission SUNRISE provided high spatial and temporal resolution images of the solar photosphere. Continuum images, longitudinal and…

Mammoths lived in Arctic East Siberia. In this region there is not sufficient sunlight over the year for the growth of the plants on which these animals feed. Therefore the latitude of this region was lower before the end of the…

During most of the Phanerozoic eon, which began about a half-billion years ago, there were few glacial intervals until the late Pliocene 2.75 million years ago. Beginning at that time, the Earth's climate entered a period of instability…

Geomagnetic field reversals remain as one of the most intriguing problems in geophysics and are regarded as chaotic processes resulting from a dynamo mechanism. In this article, we use the polarity scale data set for the last 170 Myr from…

We study the generation and evolution of density perturbations and peculiar velocities due to primordial magnetic fields. We assume that a random magnetic field was present before recombination and follow the field's effect on the baryon…