Ruprecht-Karls-Universität Heidelberg


Montag, 1. Juli 2013 - 11:00

Richard Hanson:

"Using Bayes to compute and map Galactic extinction in 3D"

Zusammenfassung. Combining multi-band photometry from SDSS and UKIDSS and training a forward model to emulate the colour-change of stellar photometry due to temperature and extinction we simultaneously solve for the astrophysical parameters extinction, temperature and distance (modulus). We introduce an HRD prior to account for previous knowledge about the distribution of stars in the temperature-absolute magnitude plane. I will detail how we can include this information and combine it with our underlying models in a consistent Bayesian framework and obtain full PDFs of the desired stellar parameters. Using these for all the stars in a given field, extinction profiles as a function of distance modulus are computed and compared. Influences of colour information, priors and model parameters are explored. Residual mean absolute errors on extinction and temperature are ~0.2mag and ~300K, respectively. Further extensions and upcoming methods to create self-consistent 3D maps will be highlighted.

Verantwortlich: , letzte Änderung am 05.04.2013 11:50 CEST
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