A 2D numerical study of explosive events in the solar atmosphere     

S.-P. Jin  B. Inhester  D. Innes 《Solar physics》1996,168(2):279-295

Two-dimensional (2D) compressible magnetohydrodynamic simulations are performed to explore the idea that the asymmetric reconnection between newly emerging intranetwork magnetic field flux and pre-existing network flux causes the explosive events in the solar atmosphere. The dependence of the reconnection rate as a function of time on the density and temperature of the emerging flux are investigated. For a Lundquist number of L _u= 5000 we find that the tearing mode instability can lead to the formation and growth of small magnetic islands. Depending on the temperature and density ratio of the emerging plasma, the magnetic island can be lifted upward and convected out of the top boundary, or is suppressed downward and convected out of the top boundary, or is suppressed downward nad submerged below the bottom boundary. The motions of the magnetic islands with different direction are accompanied respectively with upward or downward high velocity flow which might be associated with the red- and blue-shifted components detected in the explosive events.  相似文献   

Radon global simulations with the multiscale chemistry and transport model MOCAGE   总被引：2，自引：0，他引：2  

B. JOSSE  P. SIMON  V.-H. PEUCH 《Tellus. Series B, Chemical and physical meteorology》2004,56(4):339-356

  相似文献   

Simulating colour variations in pulsating sdB stars     

B. Ramachandran  C.S. Jeffery 《Astrophysics and Space Science》2004,289(3-4):441-444

After briefly recalling basic facts about the metallicity gradients inspiral galaxies, we summarize two recent N-body gas-dynamical modelsthat implement a non-instantaneous gas recycling and point our their potential for an improved treatment of the chemical evolution ingalactic disks.  相似文献   

Foraminifer zones of the callovian stage in the lower Volga region     

V. F. Saltykov 《Doklady Earth Sciences》2006,407(2):356-360

  相似文献   

Comet formation in molecular clouds     

S.V.M. Clube  W.M. Napier 《Icarus》1985,62(3):384-388

The observed properties of the long-period comet system, and its periodic disturbance by galactic forces manifesting as terrestrial impact episodes, may be indicative of a comet capture/escape cycle as the Solar System orbits the Galaxy. A mean number density of comets in molecular clouds of ～10^?1±1 AU^?3 is implied. This is sufficient to deplete metals from the gaseous component of the interstellar medium, as observed, but leads to the problem of how stars are formed nevertheless with solar metal abundances. Formation of comets prior to stars in dense systems of near-zero energy may be indicated, and isotope signatures in cometary particles may be diagnostic of conditions in young spiral arm material.  相似文献   

The new polymict eucrite Dar al Gani 983: Petrography,chemical composition,noble gas record,and evolution     

Andrea PATZER  Jochen SCHLÜTER  Ludolf SCHULTZ  Dolores H. HILL  William V. BOYNTON 《Meteoritics & planetary science》2005,40(6):869-879

Abstract— Mineralogical and chemical studies of Dar al Gani 983 show that this meteorite is a eucrite. Its texture is that of an impact breccia. It contains cumulate pyroxene and feldspar megacrysts, a variety of recrystallized melt clasts, clasts of subophitic basalt, and mesostasis. These components are embedded in a matrix of fragmental pyroxene and plagioclase. In addition, the entire rock is penetrated by glassy melt veins and patches, and displays features of strong shock. The mineralogical and chemical evidence obtained for DaG 983 indicates that this meteorite experienced a complex evolutionary history. The presence of cumulate silicate crystals implies substantial, large scale cratering events on the HED asteroid. As a result of these impacts, rocks from different intrusive bodies to extrusive surface layers were laterally and vertically transported to form a thoroughly mixed megaregolith. DaG 983 represents a sample of this megabreccia.  相似文献   

Origin of fluids responsible for the formation of Au-bearing rodingites based on isotope data: Evidence from the Karabash Alpine-type Ultramafic Massif, the southern Urals     

V. V. Murzin 《Doklady Earth Sciences》2006,407(1):254-257

  相似文献   

Thermodynamic proof of Rosseland's theorem     

A. M. Sobolev  V. S. Strel'nitskii  N. N. Chugai 《Astrophysics》1985,22(3):363-366

  相似文献   

Eclipsing binaries in extrasolar planet transit surveys: the case of SuperWASP     

B. Willems  U. Kolb  S. Justham 《Monthly notices of the Royal Astronomical Society》2006,367(3):1103-1112

  相似文献   

Infrared spectrophotometry of Comet IRAS-Araki-Alcock (1983d): a bare nucleus revealed?     

M.S. Hanner  D.K. Aitken  R. Knacke  S. McCorkle  P.F. Roche  A.T. Tokunaga 《Icarus》1985,62(1):97-109

Spectra of the central core and surrounding coma of Comet IRAS-Araki-Alcock (1983d) were obtained at 8–13 μm on 11 May and 2–4 μm on 12 May 1983. Spatially resolved measurements at 10 μm with a 4-arcsec beam showed that the central core was more than 100 times brighter than the inner coma only 8 arcsec away; for radially outflowing dust, the brightness ratio would be a factor of 8. The observations of the central core are consistent with direct detection of a nucleus having a radius of approximately 5 km. The temperature of the sunlit hemisphere was > 300 K. Spectra of the core are featureless, while spectra of the coma suggest weak silicate emission. The spectra show no evidence for icy grains. The dust producton rate on 11.4 May was ～ 10⁵ g/sec, assuming that the gas flux from the dust-producing areas on the nucleus was ～ 10^?5 g/cm²/sec.  相似文献