Artículo
Abstract:
Magnetic clouds are the interplanetary manifestation of coronal mass ejections, which are transient expulsions of major quantities of magnetized plasma, from the Sun toward the heliosphere. The magnetic flux and helicity are two key physical magnitudes to track solar structures from the photosphere-corona to the interplanetary medium. To determine the content of flux and helicity in magnetic clouds, we have to know their 3D structure. However, since spacecrafts register data along a unique direction, several aspects of their global configuration cannot be observed. We present a method to estimate the magnetic flux and the magnetic helicity per unit length in magnetic clouds, directly from in situ magnetic observations, assuming only a cylindrical symmetry for the magnetic field configuration in the observed cross-section of the cloud. We select a set of 20 magnetic clouds observed by the spacecraft Wind and estimate their magnetic flux and their helicity per unit length. We compare the results obtained from our direct method with those obtained under the assumption of a helical linear force-free field. This direct method improves previous estimations of helicity in clouds. © 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.
Registro:
| Documento: | Artículo |
| Título: | Model-independent large-scale magnetohydrodynamic quantities in magnetic clouds |
| Autor: | Dasso, S.; Gulisano, A.M.; Mandrini, C.H.; Démoulin, P. |
| Filiación: | Instituto de Astronomía y Física del Espacio (IAFE), Conicet, cc 67, 1428 Buenos Aires, Argentina Departamento de Física, FCEN, UBA, Buenos Aires, Argentina Observatoire de Paris, LESIA, UMR 8109 (CNRS), F-92195 Meudon Cedex, France |
| Palabras clave: | Astrophysical plasmas; Interplanetary medium; Magnetic clouds; Magnetic helicity; Magnetohydrodynamics; Solar wind; Astrophysics; Magnetic flux; Mathematical models; Plasmas; Solar system; Spacecraft; Wind; Astrophysical plasmas; Interplanetary medium; Magnetic clouds; Magnetic helicity; Solar wind; Magnetohydrodynamics |
| Año: | 2005 |
| Volumen: | 35 |
| Número: | 12 |
| Página de inicio: | 2172 |
| Página de fin: | 2177 |
| DOI: | http://dx.doi.org/10.1016/j.asr.2005.03.054 |
| Título revista: | Advances in Space Research |
| Título revista abreviado: | Adv. Space Res. |
| ISSN: | 02731177 |
| CODEN: | ASRSD |
| Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02731177_v35_n12_p2172_Dasso |
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Citas:
---------- APA ----------
Dasso, S., Gulisano, A.M., Mandrini, C.H. & Démoulin, P. (2005) . Model-independent large-scale magnetohydrodynamic quantities in magnetic clouds. Advances in Space Research, 35(12), 2172-2177.http://dx.doi.org/10.1016/j.asr.2005.03.054
---------- CHICAGO ----------
Dasso, S., Gulisano, A.M., Mandrini, C.H., Démoulin, P. "Model-independent large-scale magnetohydrodynamic quantities in magnetic clouds" . Advances in Space Research 35, no. 12 (2005) : 2172-2177.http://dx.doi.org/10.1016/j.asr.2005.03.054
---------- MLA ----------
Dasso, S., Gulisano, A.M., Mandrini, C.H., Démoulin, P. "Model-independent large-scale magnetohydrodynamic quantities in magnetic clouds" . Advances in Space Research, vol. 35, no. 12, 2005, pp. 2172-2177.http://dx.doi.org/10.1016/j.asr.2005.03.054
---------- VANCOUVER ----------
Dasso, S., Gulisano, A.M., Mandrini, C.H., Démoulin, P. Model-independent large-scale magnetohydrodynamic quantities in magnetic clouds. Adv. Space Res. 2005;35(12):2172-2177.http://dx.doi.org/10.1016/j.asr.2005.03.054
