INVESTIGADORES
BERTUCCI Cesar
artículos
Título:
Titan's near magnetotail from magnetic field and electron plasma observations and modeling: Cassini flybys TA, TB, and T3
Autor/es:
NEUBAUER, F. M.; BACKES, H.; DOUGHERTY, M. K.; WENNMACHER, A.; RUSSELL, C. T.; COATES, A.; YOUNG, D.; ACHILLEOS, N.; ANDRÉ, N.; ARRIDGE, C. S.; ; BERTUCCI, C.; JONES, G. H.; KHURANA, K. K.; KNETTER, T.; LAW, A.; LEWIS, G. R.; SAUR, J.
Revista:
JOURNAL OF GEOPHYSICAL RESEARCH
Editorial:
AMER GEOPHYSICAL UNION
Referencias:
Año: 2006
ISSN:
0148-0227
Resumen:
The first close Titan encounters TA, TB, and T3 of the Cassini mission
at almost the same Saturnian local time ?1030 and in the same
spatial region downstream of Titan have enabled us to study the
formation of the tail of its induced magnetosphere. The study is based
on magnetic field and electron plasma observations as well as
three-dimensional modeling. Our most important findings are the
following: (1) No crossings of a bow shock of Titan were observed, and
all encounters occurred at high plasma beta > 1 for transsonic and
trans-Alfvénic Mach numbers. (2) The magnetic draping signature
of the induced magnetosphere often shows a sharp outer boundary called
the draping boundary (DB) in the near-tail region. (3) The DB is often
occurring as a discontinuity in magnetic field spatial derivatives, and
therefore the DB is a discontinuity in the spatial distribution of
plasma currents. (4) Perpendicular to the incident flow direction the DB
shows an approximately elliptic cross section elongated along the
incident magnetic field direction and a displacement toward the Sun. (5)
We argue that the DB in the magnetic tail region corresponds to the
boundary of a structure which is analogous to an Alfvén wing at
very small beta and in our case of larger beta contains
Alfvénic and slow mode features. It forms a tail like a delta
wing in aerodynamics. (6) For the two less disturbed flybys, TA and T3,
a polarity reversal layer has been observed with thicknesses of
?320 km and ?230 km, respectively.