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Chemical fractionation and alteration trends between five nakhlites
Probing the primordial power spectra with inflationary priors
We investigate constraints on power spectra of the primordial curvature and
tensor perturbations with priors based on single-field slow-roll inflation
models. We stochastically draw the Hubble slow-roll parameters and generate the
primordial power spectra using the inflationary flow equations. Using data from
recent observations of CMB and several measurements of geometrical distances in
the late Universe, Bayesian parameter estimation and model selection are
performed for models that have separate priors on the slow-roll parameters. The
same analysis is also performed adopting the standard parameterization of the
primordial power spectra. We confirmed that the scale-invariant
Harrison-Zel'dovich spectrum is disfavored with increased significance from
previous studies. While current observations appear to be optimally modeled
with some simple models of single-field slow-roll inflation, data is not enough
constraining to distinguish these models.Comment: 23 pages, 3 figures, 7 tables, accepted for publication in JCA
Reconstruction of the Primordial Power Spectrum using Temperature and Polarisation Data from Multiple Experiments
We develop a method to reconstruct the primordial power spectrum, P(k), using
both temperature and polarisation data from the joint analysis of a number of
Cosmic Microwave Background (CMB) observations. The method is an extension of
the Richardson-Lucy algorithm, first applied in this context by Shafieloo &
Souradeep. We show how the inclusion of polarisation measurements can decrease
the uncertainty in the reconstructed power spectrum. In particular, the
polarisation data can constrain oscillations in the spectrum more effectively
than total intensity only measurements. We apply the estimator to a compilation
of current CMB results. The reconstructed spectrum is consistent with the
best-fit power spectrum although we find evidence for a `dip' in the power on
scales k ~ 0.002 Mpc^-1. This feature appears to be associated with the WMAP
power in the region 18 < l < 26 which is consistently below best--fit models.
We also forecast the reconstruction for a simulated, Planck-like survey
including sample variance limited polarisation data.Comment: 8 pages, 5 figures, comments welcom