The Energetic Charged Particle Absorption Signature of Mimas.
Abstract
Data are presented for a one-minute dip in electron intensity that was observed coherently by four different detectors at 1546:51 ERT on DOY 244/1979 as Pioneer 11 crossed the orbit of Mimas inbound during its encounter with the Saturn system. By a detailed analysis, we show that this absorption microsignature in electron intensity is plausibly attributable to the particle sweeping effect of Mimas; the radial width of the signature is caused primarily by energy dispersion in the longitudinal drift rate of electrons and not by radial diffusion; the spectrum of trapped electrons at Mimas is nearly monoenergetic, centered at kinetic energy E = 1.59 MeV with a spread delta E approx. 0.1 MeV; this narrow spectrum, which is unique in magnetospheric physics, is caused by the band-pass filtering action of the successive inner satellites, most importantly Enceladus, on an inward diffusing population of electrons; and the radial diffusion coefficient D of electrons E = 1.0 MeV is 1.0 x 10 to the -10 power R(subs)-squared at L = 4 and and probably in the range 37 to 8.3 10 to the -12 power R(subs)-squared at L = 3. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 19, 1980
- Accession Number
- ADA087941
Entities
People
- B. A. Randall
- James A. van Allen
- M. F. Thomsen
Organizations
- University of Iowa