Title: The Lightweaver 1.5D Spectral Synthesis of an MPI-AMRVAC Solar Prominence/Filament
This seminar is organised by KU Leuven's Center for mathematical Plasma-Astrophysics (CmPA).
Speaker: Jack Jenkins
Abstract: With the ever-increasing complexity of numerical magnetohydrodynamic (MHD) models designed to resemble solar prominences/filaments, equivalent and accurate representations of their corresponding observables are commensurate. In numerous previous works over more than the last decade, the observational proxies derived from MHD simulations have approximated the passband-integrated optically-thin emmissivity (η) as captured with the Atmospheric Imaging Assembly. Some more recent studies have additionally addressed the absorption properties of filaments through the inclusion of the complimentary, but Saha-approximation-limited, absorption coefficient (χ) alongside η so as to constrain the source function within the radiative transfer equation (RTE). The state-of-the-art proxies for semi optically-thick lines like Hydrogen Hα make use of tabulated, linear-approximate relationships between primitive variables and RTE quantities. Derived directly from fully non-LTE (NLTE), but isobaric/isothermal prominence slab, RTE modelling, one can use these tables to translate local conditions within the simulation, ready for any final arbitrary line-of-sight integration. Although each of these approaches/methods aid in the benchmarking of bedrock simulations, none of them do so considering the full NLTE statistical equilibrium within the raw, nonlinear MHD prominence/filament atmospheres. The recently-developed Lightweaver framework is capable of taking such arbitrary atmospheric stratifications, solving for population-specific NLTE statistical equilibrium, and assuming full partial frequency redistribution and charge conservation. We hence present the current state of our efforts to include accurate 1.5D prominence/filament geometries and boundary conditions within Lightweaver, and demonstrate theoretically-consistent formation properties and linecore contrasts for Hydrogen Hα, Calcium II IR, H & K, and Magnesium II h & k.
The seminar will be held in a hybrid mode, in person in building 200B, room 00.07 and transmitted online using the following permanent Blackboard Collaborate link, that can be used for all the upcoming seminars in this academic year:
https://eu.bbcollab.com/guest/6fc7259fc2ba4f29af721ccb6a19eefd
