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Radiative losses evaluated for all significant ions present in interplanetary gas from 4 to 215 radii - solar corona energy balance
Cometary tails relationship to interplanetary gas properties and solar wind velocities deduced from observation of type I ionic cometary tails
Observations of the interplanetary medium are considered together with the structure of the solar atmosphere and the kinetic properties of the interplanetary plasma. Methods of gas kinetics and continuum flows are examined, taking into account microscopic and macroscopic representations, the kinetic flow equations, the formal solution of the Vlasov equation, and the continuum flow equations. The collective particle behavior of that interplanetary gas is discussed along with the hydrodynamic coronal expansion, a wave-pump problem, the free expansion phenomenon, and a generalized free expansion problem.
Interplanetary gas and solar wind plasma velocities from orientations of ionic comet tails
Dimensional analysis for interplanetary gas motion during solar flares
Possible relationships of cometary brightness outbursts with the solar wind and interplanetary magnetic field are examined. Two types of outburst are distinguished: those which involve a significant brightening of both the head and the tail in a comet with a conspicuous plasma tail (Class I), and those involving the brightening of the central condensation of a previously faint comet with no detectable plasma tail (Class II). Class I bursts, as exemplified by Comet Morehouse 1908c, are attributed to the generation in the head of enhanced amounts of ions and their injection into the tail shortly before it disconnects, with ionization provided by sector boundary crossings. Class II events, as exhibited by Comet P/Tuttle-Giacobini-Kresak 1973b, are interpreted as the result of the bombardment of the nucleus by disturbed solar wind near corotated high-speed streams and sector boundaries, leading to highly exothermic chemical reactions.
Shock wave radio emission near earth and in interplanetary gas
Type I comet tails orientations dispersion attributed to nonradial plasma waves and discontinuities in interplanetary gas, calculating solar angular momentum loss rate
Studies of the solar wind on the basis of cometary plasma tail observations are considered. Niedner and Brandt (1978, 1979) have concluded that the plasma tail frequently disconnects from the cometary head, and that these disconnection events (DEs) are produced by magnetic reconnection at sector boundary passages. They proposed that the disconnections are a natural combination of Alfven's model and the solar-wind sector structure first discovered by Wilcox and Ness (1965). The DEs can be utilized as probes of interplanetary sector structure. Correlations between DEs and sector boundaries observed at earth are considered, and sector boundary properties deduced from DEs are discussed. Attention is given to a review of the warped sheet model, the latitude extent of sector structure, the sector boundary tilt, and specific sources of error in the tilt angles derived from DEs.
The reconnection process in the cometary ionosphere believed responsible for the disconnecting plasma tails phenomenon is studied through the basic equations of reconnection theory and current sheet instability criteria. It is proposed that reconnection occurs when the interplanetary magnetic fields incident on a comet that has gone just past a sector boundary are pressed into the fields captured from the previous sector. The fields are of opposite polarity, and the previously captured fields constitute the 'roots' of the plasma tail. An estimated duration of reconnection during a disconnection event (DE) of 0.75 days is used along with estimates of other cometary parameters to construct fusion region dimensions and resistivity with the adopted time scale.
Attention is focused on a form of cometary activity which has been known for some time but is poorly understood: the discarding of a plasma tail by a comet. A link is found between plasma-tail rejections and conditions in the solar wind. A model is presented in which a disconnected tail is the end result of magnetic-field-line reconnection in the cometary ionosphere caused by the traversal of a magnetic sector boundary. Observations of plasma tails appear to be the best and only method at present of mapping the interplanetary sector structure out of the ecliptic plane.
Radiative losses for all ions in the extended solar corona
Super-Alfvenic point or distance of effective corotation for loss of angular momentum in solar wind plasma
Quiet solar wind model with magnetic field numerically calculated, obtaining coronal electron densities and angular momentum near earth
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Velocity distribution functions of solar-wind protons obtained by the Vela 3 satellites have been analyzed to obtain a microscopic determination of the momentum flux along magnetic field lines with respect to a reference frame moving at the bulk speed. The determination from macroscopic parameters allows the calculation of an effective mean free path for protons at 1 AU which averages 0.06 AU and is relatively independent of solar-wind velocity w. For quiet times when w is from 300 to 400 km/sec, the experimental mean free path is 2 to 3 times smaller than the value from plasma theory. For w greater than 400 km/sec, the experimental value is 10 to 100 times smaller than the theoretical value.