HR: 1330h
AN: SM43C-06 [Abstracts]
TI: Rocket observations of auroral Z-mode emissions above and below fpe
AU: * LaBelle, J
EM: jlabelle@einstein.dartmouth.edu
AF: Dartmouth College, Department of Physics and Astronomy, Hanover, NH 03755 United States
AU: Samara, M
EM: marilia.samara@dartmouth.edu
AF: Dartmouth College, Department of Physics and Astronomy, Hanover, NH 03755 United States
AU: Kintner, P M
EM: pmk1@cornell.edu
AF: Cornell University, School of Electrical Engineering, Ithaca, NY 14153 United States
AU: Klatt, E
EM: klatt@memphis.ece.cornell.edu
AF: Cornell University, School of Electrical Engineering, Ithaca, NY 14153 United States
AU: Lynch, K A
EM: kristina.lynch@dartmouth.edu
AF: Dartmouth College, Department of Physics and Astronomy, Hanover, NH 03755 United States
AU: MacDonald, E A
EM: elizabeth.macdonald@unh.edu
AF: University of New Hampshire, Department of Physics, Durham, NH 03824 United States
AB:
The SIERRA sounding rocket was launched into an active substorm aurora north of Poker Flat, Alaska, on Jan 14, 2002,
achieving an apogee of 735 km. Instrumentation included continuous waveform measurements
of 100 kHz--5 MHz electric fields detected with a single 6-m double
probe antenna which rotated in a plane containing the ambient magnetic field.
A host of high frequency plasma waves occurred along
the trajectory, including structured whistler mode waves at 250--500 kHz,
Langmuir waves, and Z-mode waves both above and below fpe.
A particularly striking example of Z-mode waves extending well below fpe
occurred during the downleg,
640-690 s into the flight, at altitudes 651-584 km. In this paper,
we report the amplitude, frequency range, and polarization (δ E||/
δ E⊥) of these waves inferred from the measurements of
electric field using the spinning antenna and investigate the
The relation of the signals to the local electron distribution function
measured by particle instruments on the payload.
Measurements of Z-mode signals well below fpe are somewhat rare at
rocket altitudes. We interpret this observation in context
of previous low-altitude in-situ wave measurements as well as the possible relation
of these Z-mode emissions to MF-burst, a broadband
radio emissions observed at ground level at 1-4 MHz.
DE: 0689 Wave propagation (4275)
DE: 2407 Auroral ionosphere (2704)
DE: 2471 Plasma waves and instabilities
DE: 2487 Wave propagation (6934)
DE: 2704 Auroral phenomena (2407)
SC: SPA-Magnetospheric Physics [SM]
MN: 2005 Joint Assembly