In this paper, we adopt the use of the wavelet transform as a new tool to investigate the time behavior at different scales of reduced magnetic helicity, cross-helicity, and residual energy in space plasmas. The main goal is a better characterization of the fluctuations in which interplanetary flux ropes are embedded. This kind of information is still missing in the present literature, and our tool can represent the basis for a new treatment of in situ measurements of this kind of event. There is a debate about the origins of small-scale flux ropes. It has been suggested that they are formed through magnetic reconnection in the solar wind, such as across the heliospheric current sheet. On the other hand, it has also been suggested that they are formed in the corona, similar to magnetic clouds. Thus, it looks like that there are two populations, one originating in the solar wind via magnetic reconnection across the current sheet in the inner heliosphere and the other originating in the corona. Small-scale flux ropes might be the remnants of the streamer belt blobs formed from disconnection; however, a one-to-one observation of a blob and a small-scale flux rope in the solar wind has yet to be found. Within this panorama of possibilities, this new technique appears to be very promising in investigating the origins of these objects advected by the solar wind.

WAVELET ANALYSIS AS A TOOL TO LOCALIZE MAGNETIC AND CROSS-HELICITY EVENTS IN THE SOLAR WIND

PIETROPAOLO, Ermanno;
2012

Abstract

In this paper, we adopt the use of the wavelet transform as a new tool to investigate the time behavior at different scales of reduced magnetic helicity, cross-helicity, and residual energy in space plasmas. The main goal is a better characterization of the fluctuations in which interplanetary flux ropes are embedded. This kind of information is still missing in the present literature, and our tool can represent the basis for a new treatment of in situ measurements of this kind of event. There is a debate about the origins of small-scale flux ropes. It has been suggested that they are formed through magnetic reconnection in the solar wind, such as across the heliospheric current sheet. On the other hand, it has also been suggested that they are formed in the corona, similar to magnetic clouds. Thus, it looks like that there are two populations, one originating in the solar wind via magnetic reconnection across the current sheet in the inner heliosphere and the other originating in the corona. Small-scale flux ropes might be the remnants of the streamer belt blobs formed from disconnection; however, a one-to-one observation of a blob and a small-scale flux rope in the solar wind has yet to be found. Within this panorama of possibilities, this new technique appears to be very promising in investigating the origins of these objects advected by the solar wind.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11697/524
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 26
  • ???jsp.display-item.citation.isi??? 27
social impact