Observations of optical aurora modulated by resonant Alfven waves

Journal Article · Thu Jul 01 04:00:00 EDT 1993 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/93JA00435· OSTI ID:233043

Xu, B L; Samson, C; Liu, W W ^[1]

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1. Univ. of Alberta (Canada); and others

The authors present a study of the modulation behavior of optical aurora, done using the CANOPUS array to look at the optical lines 5577 and 4709{angstrom}, along with magnetometer data. They looked for modulation in the range 1 to 4 mHz, which would be an indication of Alfven wave modulation by resonant waves propagating along field lines. The authors show by several examples that such modulation is seen over an array of latitudes, and that they typically see spectral peaks near 1.3, 1.9, and 3.1 mHz, and in addition large phase shifts are observed when the effects are looked at across the latitude maximum where they are observed. These observations support resonant Alfven waves as the origin of such modulation effects.

• Sponsoring Organization: USDOE
• OSTI ID: 233043
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: A7 Vol. 98; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ALFVEN WAVES
AURORAE
MILLI HZ RANGE
MODULATION
POLAR REGIONS