Online Program Home
My Program

Abstract Details

Activity Number: 291 - Astrostatistics Interest Group: Student Paper Award
Type: Topic Contributed
Date/Time: Tuesday, July 30, 2019 : 8:30 AM to 10:20 AM
Sponsor: Astrostatistics Special Interest Group
Abstract #304795 Presentation
Title: Incorporating Uncertainties in Atomic Data into the Analysis of Solar and Stellar Observations: a Case Study in FeXIII
Author(s): Xixi Yu* and Giulio Del Zanna and David Craig Stenning and David A van Dyk and Harry P. Warren and Mark A. Weber
Companies: Imperial College of Science & Technology and University of Cambridge and Imperial College London and Imperial College London and Naval Research Laboratory and Harvard-Smithsonian Center for Astrophysics
Keywords: methods: statistica; Sun: corona
Abstract:

Physical properties of astrophysical objects cannot be measured directly but inferred by interpreting spectroscopic observations under atomic physics calculations. Intensity ratios of emission lines can be used to infer electron density and temperature structure of plasma. It is critical to understand how uncertainties in underlying atomic physics propagate to uncertainties in inferred plasma parameters. At present atomic physics databases do not include uncertainties on atomic parameters and there is no established methodology for using them. We develop models for uncertainties in emissivities for FeXIII and apply them to the interpretation of observed density sensitive lines. Incorporating these uncertainties in a Bayesian framework, we have both a pragmatic Bayesian method where atomic physics information is unaffected by observed data, and a fully Bayesian method where the data can be used to probe physics. The former generally increases the uncertainty in inferred density 5 times more than those incorporate only statistical uncertainties. The latter reduces the uncertainty in densities but identifies areas of possible systematic problems with atomic physics or intensities.


Authors who are presenting talks have a * after their name.

Back to the full JSM 2019 program