English

Adaptive Langevin Sampler for Separation of t-Distribution Modelled Astrophysical Maps

Instrumentation and Methods for Astrophysics 2015-03-17 v1 Cosmology and Nongalactic Astrophysics

Abstract

We propose to model the image differentials of astrophysical source maps by Student's t-distribution and to use them in the Bayesian source separation method as priors. We introduce an efficient Markov Chain Monte Carlo (MCMC) sampling scheme to unmix the astrophysical sources and describe the derivation details. In this scheme, we use the Langevin stochastic equation for transitions, which enables parallel drawing of random samples from the posterior, and reduces the computation time significantly (by two orders of magnitude). In addition, Student's t-distribution parameters are updated throughout the iterations. The results on astrophysical source separation are assessed with two performance criteria defined in the pixel and the frequency domains.

Keywords

Cite

@article{arxiv.1101.1396,
  title  = {Adaptive Langevin Sampler for Separation of t-Distribution Modelled Astrophysical Maps},
  author = {K. Kayabol and E. E. Kuruoglu and J. L. Sanz and B. Sankur and E. Salerno and D. Herranz},
  journal= {arXiv preprint arXiv:1101.1396},
  year   = {2015}
}

Comments

12 pages, 6 figures