Wave structure of magnetic substorms at high latitudes

Клейменова, Н. Г.; Антонова, Е. Е.; Козырева, О. В.; Малышева, Л. М.; Корнилова, Т. А.; Kornilov, I. A.

doi:10.1134/s0016793212060059

Cited by 32 publications

(14 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is because sharp increases or decreases in the magnetic field components contain a broad range of frequencies, including those which are kept by the filtering process. Also, the subcategories Pip (polar irregular pulsations) and Psc5 (storm sudden commencement Pc5) of Pi3 oscillations are frequently observed at high latitudes during substorms [ Saito , ; Kleimenova et al , ]. It appears in this example that the auroral‐latitude CNA data variations correlate well with the ones of the ULF index, both when they are due to substorms and to the presence of ULF pulsations.…”

Section: Data Analysis and Resultsmentioning

confidence: 74%

Cosmic radio noise absorption in the high‐latitude ionosphere during solar wind high‐speed streams

et al. 2017

View full text Add to dashboard Cite

The effect of solar wind high‐speed streams (HSSs) on energetic particle precipitation at auroral and subauroral latitudes (L = 3.8–5.7) is studied by using cosmic noise absorption (CNA) data measured by the Finnish riometer chain during 95 HSS events occurring between 2006 and 2008. The data are divided into “long” and “short” HSS events, depending on whether the maximum solar wind speed is reached within 24 h or later after the arrival of the corotating interaction region (CIR) at the bow shock. We find that CNA is more frequent during long events and extends to subauroral latitudes, unlike during short events. CNA is observed for at least 4 days after the CIR arrival during long events, and only 3 days during short events. In addition, CNA is divided into three categories, depending on whether it is associated with local substorm activity, with ultralow frequency (ULF) wave activity, or neither of these. Substorm‐type CNA dominates in the 21–06 magnetic local time (MLT) sector, while ULF‐type CNA dominates from morning to afternoon and follows the daily SYM‐H index variations. This indicates the importance of having energetic (E > 30 keV) electrons available for interacting with the very low frequency (VLF) chorus waves, which may be modulated by ULF waves. Finally, we find a correlation between ULF‐type CNA on the dayside and substorm activity on the nightside with a 30 min delay, suggesting that substorm injections energize electrons, which then drift to the morning and dayside, where they precipitate into the ionosphere.

show abstract

Section: Data Analysis and Resultsmentioning

confidence: 74%

Cosmic radio noise absorption in the high‐latitude ionosphere during solar wind high‐speed streams

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The aim of our work is to consider three special types of substorms, which are only recently identified: extremely intense substorms [Tsurutani B.T., et al, 2015] and substorms observed at very high latitudes [Kleimenova N.G., et al, 2012;Despirak I.V., et al, 2014]. 1) First type represents extremely intense substorms (supersubstorms -SSS) which are typically observed at auroral latitudes.…”

Section: C) Three Special Types Of Magnetic Substormsmentioning

confidence: 99%

Book of Proceedings Tenth Workshop Primorsko, Bulgaria 2019

Nikitenko¹,

Lebed²,

Fedorenko³

et al. 2019

View full text Add to dashboard Cite

The Catalogues of the solar proton events [Logachev, ed., 1982-2016] provide the homogeneous data series of events with maximum intensity of > 10 MeV solar protons J ≥ 1 cm-2 s-1 sr-1 beginning from 1970 up to now. The event rates behavior is rather smooth: the total number of such events, relative to accumulated sunspot number, is almost constant in the solar cycles 21-23 and even slightly growing in the solar cycle 24. Contrary, the total number of the most powerful (GLE) events per cycle was constant within statistical errors in the cycles 21-23, and it fell abruptly in cycle 24. Considering the conventional sources of GLEs we found that production of GLEs by X-class bursts was 3 times less in cycle 24 than in cycle 23, while production of GLEs by the >1000 km/s halo-type CMEs was 5 times lower.

show abstract

“…The DMSP data of precipitating particles show that 20 minutes before T 0 the poleward edge of the auroral oval (b5e-boundary in Fig.3b) was near BJN. For this reason, following Kleimenova et al (2012), we attributed the event to the subclass "polar substorms".…”

Section: Summary Of Pre-breakup Observationsmentioning

confidence: 99%

Polar substorm on 7 December 2015: pre-onset phenomena and features of auroral breakup

Safargaleev¹,

Kozlovsky²,

Mitrofanov³

2019

Preprint

View full text Add to dashboard Cite

Abstract. Comprehensive analysis of a moderate 600-nT substorm was performed with using simultaneous optical observations inside the auroral oval and in the polar cap, combined with data from satellites, radars, and ground magnetometers. The onset took place near the poleward boundary of the auroral oval that is not typical for classical substorms. The substorm onset was preceded by two negative excursions of the IMF Bz component with 15-min interval between them, two enhancements of the antisunward convection in the polar cap with the same repetition period, and 15-minute oscillations in geomagnetic H-component in the auroral zone. The distribution of the pulsation intensity along meridian has two local maxima – at equatorial and poleward boundaries of the auroral oval where pulsations occurred in the out-of-phase mode resembling the field-line resonance. At initial stage, the auroral breakup developed as auroral torch stretching and expanding poleward along the meridian. Some later it took a form of the large-scale coiling structure that also distinguishes the considered substorm from classical one. Magnetic, radar and AMPERE satellite data show that before the collapse the coiling structure was located between two field-aligned currents: downward at poleward boundary of structure and upward at equatorial boundary. The set of GEOTAIL satellite and ground data fits to the near-tail current disruption scenario of the substorm onset. We suggest that the 15-min oscillations might play a role in the substorm initiation.

show abstract

Wave structure of magnetic substorms at high latitudes

Cited by 32 publications

References 23 publications

Cosmic radio noise absorption in the high‐latitude ionosphere during solar wind high‐speed streams

Cosmic radio noise absorption in the high‐latitude ionosphere during solar wind high‐speed streams

Book of Proceedings Tenth Workshop Primorsko, Bulgaria 2019

Polar substorm on 7 December 2015: pre-onset phenomena and features of auroral breakup

Contact Info

Product

Resources

About