Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections
This work focuses on the interaction of a Coronal Mass Ejection (CME) with the ambient solar corona, by studying the spatial and temporal evolution of the density fluctuations observed by the SOHO/UV Coronagraph Spectrometer (UVCS) during the CME. The investigation is performed by applying a wavelet...
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| Language: | English |
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MDPI AG
2019-08-01
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| Series: | Atmosphere |
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| Online Access: | https://www.mdpi.com/2073-4433/10/8/468 |
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| author | Daniele Telloni Francesco Carbone Alessandro Bemporad Ester Antonucci |
| author_facet | Daniele Telloni Francesco Carbone Alessandro Bemporad Ester Antonucci |
| author_sort | Daniele Telloni |
| collection | DOAJ |
| description | This work focuses on the interaction of a Coronal Mass Ejection (CME) with the ambient solar corona, by studying the spatial and temporal evolution of the density fluctuations observed by the SOHO/UV Coronagraph Spectrometer (UVCS) during the CME. The investigation is performed by applying a wavelet analysis to the HI Ly<inline-formula> <math display="inline"> <semantics> <mi>α</mi> </semantics> </math> </inline-formula> 1216 Å line intensity fluctuations observed with UVCS during the CME occurred on 24 December 2006. Strong and coherent fluctuations, with a significant spatial periodicity of about 84 Mm <inline-formula> <math display="inline"> <semantics> <mrow> <mo>≃</mo> <mn>0.12</mn> </mrow> </semantics> </math> </inline-formula> R<inline-formula> <math display="inline"> <semantics> <msub> <mrow></mrow> <mo>⊙</mo> </msub> </semantics> </math> </inline-formula>, are shown to develop in about an hour along the front of the CME. The results seem to indicate the Rayleigh-Taylor (RT) instability, susceptible to the deceleration of the heavier fluid of the CME front into the lighter surrounding coronal plasma, as the likely mechanism underlying the generation of the observed plasma fluctuations. This could be the first inference of the RT instability in the outer solar corona in UV, due to the transit of a CME front in the quiet coronal plasma; this interpretation is also supported by a linear magnetohydrodynamic analysis of the RT instability. |
| first_indexed | 2024-04-13T21:44:18Z |
| format | Article |
| id | doaj.art-413c6ee17bce416e91fefdb2417943b7 |
| institution | Directory Open Access Journal |
| issn | 2073-4433 |
| language | English |
| last_indexed | 2024-04-13T21:44:18Z |
| publishDate | 2019-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Atmosphere |
| spelling | doaj.art-413c6ee17bce416e91fefdb2417943b72022-12-22T02:28:39ZengMDPI AGAtmosphere2073-44332019-08-0110846810.3390/atmos10080468atmos10080468Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass EjectionsDaniele Telloni0Francesco Carbone1Alessandro Bemporad2Ester Antonucci3National Institute for Astrophysics, Astrophysical Observatory of Torino, Via Osservatorio 20, 10025 Pino Torinese, ItalyNational Research Council, Institute of Atmospheric Pollution Research, c/o University of Calabria, 87036 Rende, ItalyNational Institute for Astrophysics, Astrophysical Observatory of Torino, Via Osservatorio 20, 10025 Pino Torinese, ItalyNational Institute for Astrophysics, Astrophysical Observatory of Torino, Via Osservatorio 20, 10025 Pino Torinese, ItalyThis work focuses on the interaction of a Coronal Mass Ejection (CME) with the ambient solar corona, by studying the spatial and temporal evolution of the density fluctuations observed by the SOHO/UV Coronagraph Spectrometer (UVCS) during the CME. The investigation is performed by applying a wavelet analysis to the HI Ly<inline-formula> <math display="inline"> <semantics> <mi>α</mi> </semantics> </math> </inline-formula> 1216 Å line intensity fluctuations observed with UVCS during the CME occurred on 24 December 2006. Strong and coherent fluctuations, with a significant spatial periodicity of about 84 Mm <inline-formula> <math display="inline"> <semantics> <mrow> <mo>≃</mo> <mn>0.12</mn> </mrow> </semantics> </math> </inline-formula> R<inline-formula> <math display="inline"> <semantics> <msub> <mrow></mrow> <mo>⊙</mo> </msub> </semantics> </math> </inline-formula>, are shown to develop in about an hour along the front of the CME. The results seem to indicate the Rayleigh-Taylor (RT) instability, susceptible to the deceleration of the heavier fluid of the CME front into the lighter surrounding coronal plasma, as the likely mechanism underlying the generation of the observed plasma fluctuations. This could be the first inference of the RT instability in the outer solar corona in UV, due to the transit of a CME front in the quiet coronal plasma; this interpretation is also supported by a linear magnetohydrodynamic analysis of the RT instability.https://www.mdpi.com/2073-4433/10/8/468sun: coronasun: coronal mass ejections (CMEs)sun: oscillationsinstabilitiesplasmasturbulence |
| spellingShingle | Daniele Telloni Francesco Carbone Alessandro Bemporad Ester Antonucci Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections Atmosphere sun: corona sun: coronal mass ejections (CMEs) sun: oscillations instabilities plasmas turbulence |
| title | Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections |
| title_full | Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections |
| title_fullStr | Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections |
| title_full_unstemmed | Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections |
| title_short | Evidence for Rayleigh-Taylor Plasma Instability at the Front of Solar Coronal Mass Ejections |
| title_sort | evidence for rayleigh taylor plasma instability at the front of solar coronal mass ejections |
| topic | sun: corona sun: coronal mass ejections (CMEs) sun: oscillations instabilities plasmas turbulence |
| url | https://www.mdpi.com/2073-4433/10/8/468 |
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