Approximating the Likelihood Function of CMB Experiments

J. G. Bartlett; A. Blanchard; M. Douspis; M. Le Dour

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Approximating the Likelihood Function of CMB Experiments

J. G. Bartlett·A. Blanchard·M. Douspis·M. Le Dour

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Abstract

We discuss the problem of constraining cosmological parameters with cosmic microwave background band--power estimates. Because these latter are variances, they do not have gaussian distribution functions and, hence, the standard $χ^2$--approach is not strictly applicable. A general purpose approximation to experimental band--power likelihood functions is proposed, which requires only limited experimental details. Comparison with the full likelihood function calculated for several experiments shows that the approximation works well.

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J. G. Bartlett, A. Blanchard, M. Douspis, M. Le Dour. 1998-10-20. Approximating the Likelihood Function of CMB Experiments. https://arxiv.org/abs/astro-ph/9810316

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