Spatial shell structure of the novas DQ Her and HR Del     

L. S. Pilyugin 《Astrophysics》1985,23(2):527-533

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The response of the mid-latitude thermospheric wind to magnetic activity     

T. Yagi  P.L. Dyson 《Planetary and Space Science》1985,33(4):461-467

Observations of the thermospheric wind at a mid-latitude station have been made using a Fabry-Perot interferometer to measure the Doppler shift of the nighttime OI emission at 630 nm. The results from 12 summer nights show that the zonal wind has a distinct feature associated with magnetic activity. The zonal wind first reverses and becomes westward. The maximum strength of the westward wind, its duration, and the maximum strength of the subsequent eastward wind all increase with increasing magnetic activity. The meridional wind is less consistent in its behaviour. It is normally equatorward but during magnetic activity it can increase, decrease, or even reverse, although it is consistently equatorward and of increased strength after 02.00 L.T. The initial reversal of the zonal wind is consistent with changes in the wind expected as a result of convective electric fields penetrating to mid-latitudes indicating that these electric fields modify the mid-latitude wind pattern before effects due to auroral heating reach mid-latitudes. The reversal of the zonal wind back to eastward may also be the result of electric field effects. The large variability of the meridional wind, to the extent that it becomes poleward at times, indicates the importance of wind sources equatorward of the observatory.  相似文献   

Spatially resolved spectrophotometry of comet P/Stephan-Oterma     

Anita L. Cochran  Edwin S. Barker 《Icarus》1985,62(1):72-81

Observations of Comet P/Stephan-Oterma were made with an Intensified Dissector Scanner spectrograph on the McDonald Observatory 2.7-m telescope during the period from July 1980 to February 1981. These spectra cover a range of heliocentric distances from 2.3 AU preperihelion to 1.8 AU postperihelion. A small aperture was used to map the spatial distributions of the gases in the coma. Column densities of the observed cometary emissions (CN, C₃, CH, and C₂) were calculated and it is shown that Stephan-Oterma appeared nearly spherically symmetric. These date are used by Cochran (1985, Icarus62, 82–92) to constrain chemical models of Stephan-Oterma.  相似文献   

Preface     

R L D  J H L  P K S 《Celestial Mechanics and Dynamical Astronomy》1985,37(3):vii-vii

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On 'The relationship between the magnitude and direction of the geomagnetic field during the late Tertiary in Eastern Iceland' by N. Roberts and J. Shaw     

L. Kristánsson 《Geophysical Journal International》1985,80(2):555-559

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Estimation of the frequency dependence of Q from ScP and ScS phases     

L. J. Burdick 《Geophysical Journal International》1985,80(1):35-55

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Metals in tissues and skeleton of Fungia fungites from Phuket, Thailand     

L.S. Howard  B.E. Brown   《Marine pollution bulletin》1986,17(12):569-570

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Petrogenesis of andalusite–kyanite–sillimanite veins and host rocks, Sanandaj-Sirjan metamorphic belt, Hamadan, Iran     

A. A. Sepahi  D. L. Whitney  A. A. Baharifar 《Journal of Metamorphic Geology》2004,22(2):119-134

Quartz‐rich veins in metapelitic schists of the Sanandaj‐Sirjan belt, Hamadan region, Iran, commonly contain two Al₂SiO₅ polymorphs, and, more rarely, three coexisting Al₂SiO₅ polymorphs. In most andalusite and sillimanite schists, the types of polymorphs in veins correlate with Al₂SiO₅ polymorph(s) in the host rocks, although vein polymorphs are texturally and compositionally distinct from those in adjacent host rocks; e.g. vein andalusite is enriched in Fe₂O₃ relative to host rock andalusite. Low‐grade rocks contain andalusite + quartz veins, medium‐grade rocks contain andalusite + sillimanite + quartz ± plagioclase veins, and high‐grade rocks contain sillimanite + quartz + plagioclase veins/leucosomes. Although most andalusite and sillimanite‐bearing veins occur in host rocks that also contain Al₂SiO₅, kyanite‐quartz veins crosscut rocks that lack Al₂SiO₅ (e.g. staurolite schist, granite). A quartz vein containing andalusite + kyanite + sillimanite + staurolite + muscovite occurs in andalusite–sillimanite host rocks. Textural relationships in this vein indicate the crystallization sequence andalusite to kyanite to sillimanite. This crystallization sequence conflicts with the observation that kyanite‐quartz veins post‐date andalusite–sillimanite veins and at least one intrusive phase of a granite that produced a low‐pressure–high‐temperature contact aureole; these relationships imply a sequence of andalusite to sillimanite to kyanite. Varying crystallization sequences for rocks in a largely coherent metamorphic belt can be explained by P–T paths of different rocks passing near (slightly above, slightly below) the Al₂SiO₅ triple point, and by overprinting of multiple metamorphic events in a terrane that evolved from a continental arc to a collisional orogen.  相似文献   

Simultaneous XMM–Newton and ESO VLT observations of supernova 1995N: probing the wind–ejecta interaction     

L. Zampieri  P. Mucciarelli  A. Pastorello  M. Turatto  E. Cappellaro  S. Benetti 《Monthly notices of the Royal Astronomical Society》2005,364(4):1419-1428

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Direct mid-IR images of Gl 2591,W51-IRS2 and S140     

P. Persi  M. Ferrari-Toniolo  A. R. Marenzi  M. Busso  L. Corcione  M. Marengo  M. Tapia 《Astrophysics and Space Science》1995,224(1-2):535-536

We present the results of direct mid-IR images of the luminous young stellar objects GL 2591, S140-IRS1, and W51-IRS2. The sources show an extended mid-IR emission at the limit of our spatial resolution indicating the presence of dense circumstellar dust disks.  相似文献