Analytical model for gyro-phase drift arising from abrupt inhomogeneity. (June 2014)

• Record Type: Journal Article
• Authors: Walker, Jeffrey J.; Koepke, M. E.; Zimmerman, M. I.; Farrell, W. M.; Demidov, V. I.
• Is Part Of: Journal of plasma physics. Volume 80:Number 3(2014:Jun.)
• Page Start: 395
• Page End: 404
• Publication Date: 2014-06
• Subjects: Plasma (Ionized gases) -- Periodicals; 530.4405
• DOI: 10.1017/S0022377813001359
• Languages: English
• ISSNs: 0022-3778

Abstract

<abstract abstract-type="normal"> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <p>If a magnetized-orbit-charged grain encounters any abrupt inhomogeneity in plasma conditions during a gyro-orbit, such that the resulting <italic>in-situ</italic> equilibrium charge is significantly different between these regions (<italic>q</italic>₁/<italic>q</italic>₂ ~ 2, where <italic>q</italic>₁ is the <italic>in-situ</italic> equilibrium charge on one side of the inhomogeneity, <italic>q</italic>₂ is the <italic>in-situ</italic> equilibrium charge on the other side, and <italic>q</italic>₁ &lt; <italic>q</italic>₂ &lt; 0), then the capacitive effects of charging and discharging of the dust grain can result in a modification to the orbit-averaged grain trajectory, i.e. gyro-phase drift. The special case of <italic>q</italic>₁/<italic>q</italic>₂ is notioned for the purpose of illustrating the utility of the method. An analytical expression is derived for the grain velocity, assuming a capacitor approximation to the OML charging model. For cases in which a strong electric field suddenly appears in the wake or at the space-plasma-to-crater interface from solar wind and/or ultraviolet illumination and in which a magnetic field permeates an asteroid, comet, or moon, this model could contribute to the interpretation of the distribution of fields and particles.</p> </abstract>