Science Seminars

12/11/2015- Towards a deeper understanding of solar spectra through forward modelling

Speaker: Tiago M. D. Pereira (Univ. of Oslo)
Date: Saturday, Dec 11, 2021
Time: 11:00 AM
Location: SPSC N100

Seminar Abstract:

Most of our knowledge of the Sun is derived from light emitted in its thin, outer atmospheric layers, from where most photons can reach us unimpeded. Yet extracting physical information from images and spectra
is a task far from simple. One needs a model of the solar atmosphere to calculate synthetic spectra that can be compared with observations. In this talk I will detail how we used 3D MHD simulations to synthesise spectral lines observed by the IRIS mission. IRIS was launched to study the flow of energy through different parts of the solar atmosphere. In  this forward modelling exercise we derive key relations between the IRIS spectral observables and thermodynamic quantities from the atmosphere. But the path is tortuous. Can they be trusted? There are many limitations, from numerical to model dependent. Yet I will argue that this is one of the most reliable methods for extracting information from spectra, and that such work is becoming increasingly relevant as observations get more and more complex.