Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/24513
Title: | Determination of Coronal Mass Ejection Physical Parameters from a Combination of Polarized Visible Light and UV Lyα Observations | Authors: | SUSINO, ROBERTO BEMPORAD, Alessandro |
Issue Date: | 2016 | Journal: | THE ASTROPHYSICAL JOURNAL | Number: | 830 | Issue: | 2 | First Page: | 58 | Abstract: | Visible-light observations of Coronal Mass Ejections (CMEs) performed with coronagraphs and heliospheric imagers (in primis on board the Solar and Heliospheric Observatory and STEREO missions) have offered the best way to study the kinematics and geometrical structure of these fundamental events so far. Nevertheless, it has been widely demonstrated that only combination of multi-wavelength data (including X-ray spectra, EUV images, EUV-UV spectra, and radio dynamic spectra) can provide complete information on the plasma temperature and density distributions, non-thermal motions, magnetic fields, and other physical parameters, for both CMEs and CME-related phenomena. In this work, we analyze three CMEs by combining simultaneous data acquired in the polarized visible light by the LASCO-C2 coronagraph and in the UV H I Lyα line (1216 Å) by the UVCS spectrometer, in order to estimate the CME plasma electron density (using the polarization-ratio technique to infer the 3D structure of the CME) and temperature (from the comparison between the expected and measured Lyα intensities) along the UVCS field of view. This analysis is primarily aimed at testing the diagnostic methods that will be applied to coronagraphic observations of CMEs delivered by the Metis instrument on board the next ESA-Solar Orbiter mission. We find that CME cores are usually associated with cooler plasma (T∼ {10}<SUP>6</SUP> K), and that a significant increase of the electron temperatures is observed from the core to the front of the CME (where T\gt {10}<SUP>6.3</SUP> K), which seems to be correlated, in all cases, with the morphological structure of the CME as derived from visible-light images. | URI: | http://hdl.handle.net/20.500.12386/24513 | URL: | https://iopscience.iop.org/article/10.3847/0004-637X/830/2/58 | ISSN: | 0004-637X | DOI: | 10.3847/0004-637X/830/2/58 | Bibcode ADS: | 2016ApJ...830...58S | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
Susino_2016_ApJ_830_58.pdf | pdf editoriale | 14.36 MB | Adobe PDF | View/Open |
24513-Susino_2016_ApJ_830_58_P01.pdf | Miur | 6.82 MB | Adobe PDF | |
24513-Susino_2016_ApJ_830_58_P02.pdf | Miur | 7.6 MB | Adobe PDF |
Page view(s)
58
checked on Mar 19, 2024
Download(s)
15
checked on Mar 19, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.