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A 2.5-dimensional MHD Alfvén-wave-driven solar wind model
Habbal, S. R.; Li, X.; Hu, Y. Q.
A 2.5-dimensional MHD analysis of Alfvén-wave-driven solar wind in the heliospheric meridional plane is presented in order to extend the one-dimensional model proposed by [1967] to the two-dimensional case. In our model, no energy input is applied to the helmet streamer, while the solar wind along open field lines is assumed to be driven by Alfvén…
Star Formation and X-Ray Emission in Distant Star-Forming Galaxies
Cohen, Judith G.
About 45% of the point sources detected in the 2 Ms Chandra exposure of the Hubble Deep Field-North (HDF-N) can be matched with moderately bright galaxies with z<1.4 that have been studied by the Caltech Faint Galaxy Redshift Survey. Although the optical spectra of these galaxies appear normal, based on their X-ray properties ~20% of them appea…
Model for vortex turbulence with discontinuities in the solar wind
Tsurutani, B. T.; Verkhoglyadova, O. P.; Dasgupta, B.
A model of vortex with embedded discontinuities in plasma flow is developed in the framework of ideal MHD in a low b plasma. Vortex structures are considered as a result of 2-D evolution of nonlinear shear Alfvén waves in the heliosphere. Physical properties of the solutions and vector fields are analyzed and the observational aspects of the model…
Atomic Data and Emission-Line Intensities for Ca VII
Bhatia, A. K.; Landi, E.
In the present work we calculate energy levels, transition probabilities, and electron-ion collisional excitation rates for the 3s23p2, 3s3p3, and 3s23p3d configurations of the silicon-like ion Ca VII. The total number of intermediate coupling levels considered is 27. Collision strengths are calculated a…
Strong interplanetary field enhancements at Ulysses—evidence of dust trails' interaction with the solar wind?
Balogh, André; Jones, Geraint H.; MacDowall, Robert J. +1 more
Interplanetary field enhancements were first discovered in the vicinity of Venus. These events are characterised by an increase in the magnitude of the heliospheric magnetic field with a near-symmetrical, sometimes thorn-shaped profile, and last from minutes to hours. Surveys of the events near Venus and Earth indicated clustering of the events in…
On ion-cyclotron-resonance heating of the corona and solar wind
Tu, C. -Y.; Marsch, E.; Vocks, C.
This paper concisely summarizes and critically reviews recent work by the authors on models of the heating of the solar corona by resonance of ions with high-frequency waves (up to the proton cyclotron frequency). The quasi-linear theory of pitch angle diffusion is presented in connection with relevant solar wind proton observations. Hybrid fluid-…
The Orion nebula (M42) Herbig-Haro object, HH 201, within the tip of a molecular finger
Redman, M. P.; Meaburn, J.; Graham, M. F.
The most prominent Herbig-Haro (HH) object, HH 201, in the Orion nebula is investigated using optical spectroscopy along with optical and infrared images. An infrared Subaru H2v= 1-0 S(1) image of the region surrounding the optical line emission of HH 201 has yielded the discovery of a faint H2 finger associated with HH 201. …
Mars atmospheric water vapor abundance: 1996-1997
Doose, L. R.; Hunten, D. M.; Sprague, A. L. +1 more
Measurements of martian atmospheric water vapor made throughout Ls = 18.0°-146.4° (October 3, 1996-July 12, 1997) show changes in Mars humidity on hourly, daily, and seasonal time scales. Because our observing program during the 1996-1997 Mars apparition did not include concomitant measurement of nearby CO 2 bands, high north…
Interaction of an Erupting Filament with the Ambient Magnetoplasma and Escape of Electron Beams
Vršnak, Bojan; Warmuth, Alexander; Otruba, Wolfgang +2 more
A huge filament eruption of 12 September 2000 associated with a two-ribbon spotless flare is described. During the acceleration phase the shape of the filament changed, and signatures of topological restructuring of large-scale coronal magnetic fields were inferred by tracking changes of nearby coronal holes. At the same time electron beams associ…
High Spectral Resolution H2 Measurements of Herbig-Haro Objects 38, 46/47, and 120
Schwartz, Richard D.; Greene, Thomas P.
We report high spectral resolution (R~=20,000) measurements of the H2 1-0S(1) line in Herbig-Haro objects 38, 46/47, and 120. The long-slit spectra reveal complex velocity structure with evidence for bow-shock structures, as well as prompt entrainment and shock heating of ambient molecular gas. Individual knots within HH 38 show distinc…