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dc.date.accessioned2019-04-17T10:38:48Z
dc.date.available2019-04-17T10:38:48Z
dc.date.created2019-01-18T16:58:19Z
dc.date.issued2018
dc.identifier.citationLeenarts, Jorrit de la Cruz Rodriguez, Jaime Danilovic, Sanja Scharmer, Göran B. Carlsson, Mats . Chromospheric heating during flux emergence in the solar atmosphere. Astronomy and Astrophysics. 2018, 612
dc.identifier.urihttp://hdl.handle.net/10852/67718
dc.description.abstractContext: The radiative losses in the solar chromosphere vary from 4 kW m−2 in the quiet Sun, to 20 kW m−2 in active regions. The mechanisms that transport non-thermal energy to and deposit it in the chromosphere are still not understood. Aim: We aim to investigate the atmospheric structure and heating of the solar chromosphere in an emerging flux region. Methods: We have used observations taken with the CHROMIS and CRISP instruments on the Swedish 1-m Solar Telescope in the Ca II K , Ca II 854.2 nm, Hα, and Fe I 630.1 nm and 630.2 nm lines. We analysed the various line profiles and in addition perform multi-line, multi-species, non-local thermodynamic equilibrium (non-LTE) inversions to estimate the spatial and temporal variation of the chromospheric structure. Results: We investigate which spectral features of Ca II K contribute to the frequency-integrated Ca II K brightness, which we use as a tracer of chromospheric radiative losses. The majority of the radiative losses are not associated with localised high-Ca II K-brightness events, but instead with a more gentle, spatially extended, and persistent heating. The frequency-integrated Ca II K brightness correlates strongly with the total linear polarization in the Ca II 854.2 nm, while the Ca II K profile shapes indicate that the bulk of the radiative losses occur in the lower chromosphere. Non-LTE inversions indicate a transition from heating concentrated around photospheric magnetic elements below log τ500 = −3 to a more space-filling and time-persistent heating above log τ500 = −4. The inferred gas temperature at log τ500 = −3.8 correlates strongly with the total linear polarization in the Ca II 854.2 nm line, suggesting that that the heating rate correlates with the strength of the horizontal magnetic field in the low chromosphere.en_US
dc.languageEN
dc.publisherEDP Sciences
dc.titleChromospheric heating during flux emergence in the solar atmosphereen_US
dc.typeJournal articleen_US
dc.creator.authorLeenarts, Jorrit
dc.creator.authorde la Cruz Rodriguez, Jaime
dc.creator.authorDanilovic, Sanja
dc.creator.authorScharmer, Göran B.
dc.creator.authorCarlsson, Mats
cristin.unitcode185,15,3,40
cristin.unitnameRosseland senter for solfysikk
cristin.ispublishedtrue
cristin.fulltextoriginal
cristin.qualitycode2
dc.identifier.cristin1660646
dc.identifier.bibliographiccitationinfo:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Astronomy and Astrophysics&rft.volume=612&rft.spage=&rft.date=2018
dc.identifier.jtitleAstronomy and Astrophysics
dc.identifier.volume612
dc.identifier.pagecount12
dc.identifier.doihttp://dx.doi.org/10.1051/0004-6361/201732027
dc.identifier.urnURN:NBN:no-70876
dc.type.documentTidsskriftartikkelen_US
dc.type.peerreviewedPeer reviewed
dc.source.issn0004-6361
dc.identifier.fulltextFulltext https://www.duo.uio.no/bitstream/handle/10852/67718/2/aa32027-17.pdf
dc.type.versionPublishedVersion
cristin.articleidA28
dc.relation.projectNFR/262622


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