eprintid: 10190848
rev_number: 6
eprint_status: archive
userid: 699
dir: disk0/10/19/08/48
datestamp: 2024-04-17 08:54:32
lastmod: 2024-04-17 08:54:32
status_changed: 2024-04-17 08:54:32
type: article
metadata_visibility: show
sword_depositor: 699
creators_name: Long, David M
creators_name: Baker, Deborah
creators_name: To, Andy SH
creators_name: van Driel-Gesztelyi, Lidia
creators_name: Brooks, David H
creators_name: Stangalini, Marco
creators_name: Murabito, Mariarita
creators_name: James, Alexander W
creators_name: Mathioudakis, Mihalis
creators_name: Testa, Paola
title: Identifying Plasma Fractionation Processes in the Chromosphere Using IRIS
ispublished: pub
divisions: UCL
divisions: B04
divisions: C06
divisions: F63
note: Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
abstract: The composition of the solar corona differs from that of the photosphere, with the plasma thought to fractionate in the solar chromosphere according to the first ionization potential (FIP) of the different elements. This produces a FIP bias, wherein elements with a low FIP are preferentially enhanced in the corona compared to their photospheric abundance, but direct observations of this process remain elusive. Here, we use a series of spectroscopic observations of active region AR 12759 as it transited the solar disk over a period of 6 days from 2020 April 2–7 taken using the Hinode Extreme ultraviolet Imaging Spectrometer and Interface Region Imaging Spectrograph (IRIS) instruments to look for signatures of plasma fractionation in the solar chromosphere. Using the Si x/S x and Ca xiv/Ar xiv diagnostics, we find distinct differences between the FIP bias of the leading and following polarities of the active region. The widths of the IRIS Si iv lines exhibited clear differences between the leading and following polarity regions, indicating increased unresolved wave activity in the following polarity region compared to the leading polarity region, with the chromospheric velocities derived using the Mg ii lines exhibiting comparable, albeit much weaker, behavior. These results are consistent with plasma fractionation via resonant/nonresonant waves at different locations in the solar chromosphere following the ponderomotive force model, and indicate that IRIS could be used to further study this fundamental physical process.
date: 2024-04-08
date_type: published
publisher: American Astronomical Society
official_url: http://dx.doi.org/10.3847/1538-4357/ad3234
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 2268071
doi: 10.3847/1538-4357/ad3234
lyricists_name: Long, David
lyricists_name: Baker, Deborah
lyricists_name: James, Alexander William
lyricists_id: DMLON63
lyricists_id: DBAKE94
lyricists_id: AWJAM85
actors_name: Kalinowski, Damian
actors_id: DKALI47
actors_role: owner
full_text_status: public
publication: The Astrophysical Journal
volume: 965
number: 1
article_number: 63
issn: 0004-637X
citation:        Long, David M;    Baker, Deborah;    To, Andy SH;    van Driel-Gesztelyi, Lidia;    Brooks, David H;    Stangalini, Marco;    Murabito, Mariarita;             ... Testa, Paola; + view all <#>        Long, David M;  Baker, Deborah;  To, Andy SH;  van Driel-Gesztelyi, Lidia;  Brooks, David H;  Stangalini, Marco;  Murabito, Mariarita;  James, Alexander W;  Mathioudakis, Mihalis;  Testa, Paola;   - view fewer <#>    (2024)    Identifying Plasma Fractionation Processes in the Chromosphere Using IRIS.                   The Astrophysical Journal , 965  (1)    , Article 63.  10.3847/1538-4357/ad3234 <https://doi.org/10.3847/1538-4357%2Fad3234>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10190848/1/Long_Identifying%20Plasma%20Fractionation%20Processes%20in%20the%20Chromosphere%20Using%20IRIS_VoR.pdf