Time-resolved XUV opacity measurements of warm-dense aluminium
The free-free opacity in plasmas is fundamental to our understanding of energy transport in stellar interiors and for inertial confinement fusion research. However, theoretical predictions in the challenging dense plasma regime are conflicting and there is a dearth of accurate experimental data to a...
| Main Authors: | , , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
American Physical Society
2020
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| _version_ | 1797098176035946496 |
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| author | Vinko, S Vozda, V Andreasson, J Ciricosta, O Hollebon, P Kasim, MF Rackstraw, DS Wark, JS |
| author_facet | Vinko, S Vozda, V Andreasson, J Ciricosta, O Hollebon, P Kasim, MF Rackstraw, DS Wark, JS |
| author_sort | Vinko, S |
| collection | OXFORD |
| description | The free-free opacity in plasmas is fundamental to our understanding of energy transport in stellar interiors and for inertial confinement fusion research. However, theoretical predictions in the challenging dense plasma regime are conflicting and there is a dearth of accurate experimental data to allow for direct model validation. Here we present time-resolved transmission measurements in solid-density Al heated by an XUV free-electron laser. We use a novel functional optimization approach to extract the temperature-dependent absorption coefficient directly from an oversampled pool of single-shot measurements, and find a pronounced enhancement of the opacity as the plasma is heated to temperatures of order of the Fermi energy. Plasma heating and opacity enhancement are observed on ultrafast timescales, within the duration of the femtosecond XUV pulse. We attribute further rises in the opacity on ps timescales to melt and the formation of warm dense matter. |
| first_indexed | 2024-03-07T05:05:51Z |
| format | Journal article |
| id | oxford-uuid:d9e38d12-37f2-4f64-967c-9ec53a5cf3b2 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T05:05:51Z |
| publishDate | 2020 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | oxford-uuid:d9e38d12-37f2-4f64-967c-9ec53a5cf3b22022-03-27T08:59:16ZTime-resolved XUV opacity measurements of warm-dense aluminiumJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:d9e38d12-37f2-4f64-967c-9ec53a5cf3b2EnglishSymplectic ElementsAmerican Physical Society2020Vinko, SVozda, VAndreasson, JCiricosta, OHollebon, PKasim, MFRackstraw, DSWark, JSThe free-free opacity in plasmas is fundamental to our understanding of energy transport in stellar interiors and for inertial confinement fusion research. However, theoretical predictions in the challenging dense plasma regime are conflicting and there is a dearth of accurate experimental data to allow for direct model validation. Here we present time-resolved transmission measurements in solid-density Al heated by an XUV free-electron laser. We use a novel functional optimization approach to extract the temperature-dependent absorption coefficient directly from an oversampled pool of single-shot measurements, and find a pronounced enhancement of the opacity as the plasma is heated to temperatures of order of the Fermi energy. Plasma heating and opacity enhancement are observed on ultrafast timescales, within the duration of the femtosecond XUV pulse. We attribute further rises in the opacity on ps timescales to melt and the formation of warm dense matter. |
| spellingShingle | Vinko, S Vozda, V Andreasson, J Ciricosta, O Hollebon, P Kasim, MF Rackstraw, DS Wark, JS Time-resolved XUV opacity measurements of warm-dense aluminium |
| title | Time-resolved XUV opacity measurements of warm-dense aluminium |
| title_full | Time-resolved XUV opacity measurements of warm-dense aluminium |
| title_fullStr | Time-resolved XUV opacity measurements of warm-dense aluminium |
| title_full_unstemmed | Time-resolved XUV opacity measurements of warm-dense aluminium |
| title_short | Time-resolved XUV opacity measurements of warm-dense aluminium |
| title_sort | time resolved xuv opacity measurements of warm dense aluminium |
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