Mathematics – Probability
Scientific paper
Jun 1986
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1986p%26ss...34..543k&link_type=abstract
Planetary and Space Science (ISSN 0032-0633), vol. 34, June 1986, p. 543-553. Research supported by the Academy of Finland.
Mathematics
Probability
25
Extremely Low Radio Frequencies, Geomagnetic Micropulsations, Geomagnetism, Sudden Storm Commencements, Alaska, Finland, Magnetometers, Radio Spectra, Solar Terrestrial Interactions, Time Dependence
Scientific paper
A survey of ULF emissions associated with sudden compressions of the magnetosphere due to sudden impulses (SI or ssc) is conducted on the basis of induction coil magnetometer recordings collected in Finland and Alaska during 1976-1979. Several examples are presented to illustrate the utility in classifying the emissions according to their spectral characteristics. The most common emissions are Pc1 pulsations. These show a maximum occurrence in the noon-afternoon sector and may undergo drastic variations in form as a function of latitude along one meridian. Pulsations which occur both in Finland and Alaska, at the same latitude separated by 175 deg, show very little similarity. A SI amplitude threshold of approximately 10 nT is necessary for the stimulation of Pc1 pulsations, however, if there is previous Pc1 activity this threshold is lowered. AS SI amplitudes rise above 25 nT, the probability of observing ULF emissions rises dramatically. It is noted that SI often trigger band-limited bursts of ULF emissions near 1 Hz. These bursts are short-lived with durations of a few minutes and occur a few minutes after the SI. They are most common during years of high solar activity. It is concluded that the stimulation of different types of ULF emissions by SIs reflects the state of the magnetosphere at the time of the SI.
Aikio Anita
Kangas Jorma
Olson John V.
No associations
LandOfFree
Multistation correlation of ULF pulsation spectra associated with sudden impulses does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Multistation correlation of ULF pulsation spectra associated with sudden impulses, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multistation correlation of ULF pulsation spectra associated with sudden impulses will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1833964