dc.date.accessioned | 2022-01-25T18:20:50Z | |
dc.date.available | 2022-01-25T18:20:50Z | |
dc.date.created | 2021-12-21T09:09:53Z | |
dc.date.issued | 2021 | |
dc.identifier.citation | Mulay, Sargam M. Fletcher, Lyndsay . Evidence of chromospheric molecular hydrogen emission in a solar flare observed by the IRIS satellite. Monthly notices of the Royal Astronomical Society. 2021, 504(2), 2842-2852 | |
dc.identifier.uri | http://hdl.handle.net/10852/90059 | |
dc.description.abstract | We have carried out the first comprehensive investigation of enhanced line emission from molecular hydrogen, H2 at 1333.79 Å, observed at flare ribbons in SOL2014-04-18T13:03. The cool H2 emission is known to be fluorescently excited by Si iv 1402.77 Å UV radiation and provides a unique view of the temperature minimum region (TMR). Strong H2 emission was observed when the Si iv 1402.77 Å emission was bright during the flare impulsive phase and gradual decay phase, but it dimmed during the GOES peak. H2 line broadening showed non-thermal speeds in the range 7–18 kms−1, possibly corresponding to turbulent plasma flows. Small red (blue) shifts, up to 1.8 (4.9) kms−1 were measured. The intensity ratio of Si iv 1393.76 Å and Si iv 1402.77 Å confirmed that plasma was optically thin to Si iv (where the ratio = 2) during the impulsive phase of the flare in locations where strong H2 emission was observed. In contrast, the ratio differs from optically thin value of 2 in parts of ribbons, indicating a role for opacity effects. A strong spatial and temporal correlation between H2 and Si iv emission was evident supporting the notion that fluorescent excitation is responsible. | |
dc.language | EN | |
dc.rights | Attribution 4.0 International | |
dc.rights.uri | https://creativecommons.org/licenses/by/4.0/ | |
dc.title | Evidence of chromospheric molecular hydrogen emission in a solar flare observed by the IRIS satellite | |
dc.type | Journal article | |
dc.creator.author | Mulay, Sargam M. | |
dc.creator.author | Fletcher, Lyndsay | |
cristin.unitcode | 185,15,3,40 | |
cristin.unitname | Rosseland senter for solfysikk | |
cristin.ispublished | true | |
cristin.fulltext | original | |
cristin.qualitycode | 1 | |
dc.identifier.cristin | 1970854 | |
dc.identifier.bibliographiccitation | info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Monthly notices of the Royal Astronomical Society&rft.volume=504&rft.spage=2842&rft.date=2021 | |
dc.identifier.jtitle | Monthly notices of the Royal Astronomical Society | |
dc.identifier.volume | 504 | |
dc.identifier.issue | 2 | |
dc.identifier.startpage | 2842 | |
dc.identifier.endpage | 2852 | |
dc.identifier.doi | https://doi.org/10.1093/mnras/stab367 | |
dc.identifier.urn | URN:NBN:no-92745 | |
dc.subject.nvi | VDP::Astrofysikk, astronomi: 438 | |
dc.type.document | Tidsskriftartikkel | |
dc.type.peerreviewed | Peer reviewed | |
dc.source.issn | 0035-8711 | |
dc.identifier.fulltext | Fulltext https://www.duo.uio.no/bitstream/handle/10852/90059/1/stab367.pdf | |
dc.type.version | PublishedVersion | |
dc.relation.project | NFR/262622 | |