Hierarchical Bayesian detection algorithm for early-universe relics in the cosmic microwave background

File Description SizeFormat 
Hierarchical-Bayesian-detection-algorithm.pdfPublished version2.59 MBAdobe PDFView/Open
Title: Hierarchical Bayesian detection algorithm for early-universe relics in the cosmic microwave background
Authors: Feeney, SM
Johnson, MC
McEwen, JD
Mortlock, DJ
Peiris, HV
Item Type: Journal Article
Abstract: A number of theoretically well-motivated additions to the standard cosmological model predict weak signatures in the form of spatially localized sources embedded in the cosmic microwave background (CMB) fluctuations. We present a hierarchical Bayesian statistical formalism and a complete data analysis pipeline for testing such scenarios. We derive an accurate approximation to the full posterior probability distribution over the parameters defining any theory that predicts sources embedded in the CMB, and perform an extensive set of tests in order to establish its validity. The approximation is implemented using a modular algorithm, designed to avoid a posteriori selection effects, which combines a candidate-detection stage with a full Bayesian model-selection and parameter-estimation analysis. We apply this pipeline to theories that predict cosmic textures and bubble collisions, extending previous analyses by using: (1) adaptive-resolution techniques, allowing us to probe features of arbitrary size, and (2) optimal filters, which provide the best possible sensitivity for detecting candidate signatures. We conclude that the WMAP 7-year data do not favor the addition of either cosmic textures or bubble collisions to Λ CDM , and place robust constraints on the predicted number of such sources. The expected numbers of bubble collisions and cosmic textures on the CMB sky within our detection thresholds are constrained to be fewer than 4.0 and 5.2 at 95% confidence, respectively.
Issue Date: 26-Aug-2013
Date of Acceptance: 1-Aug-2013
URI: http://hdl.handle.net/10044/1/73490
DOI: https://doi.org/10.1103/PhysRevD.88.043012
ISSN: 2470-0010
Publisher: American Physical Society
Journal / Book Title: Physical Review D
Volume: 88
Issue: 4
Copyright Statement: © 2013 American Physical Society.
Sponsor/Funder: Science and Technology Facilities Council (STFC)
Science and Technology Facilities Council [2006-2012]
Science and Technology Facilities Council [2006-2012]
Funder's Grant Number: ST/K001051/1
ST/K001051/1
ST/K001051/1
Keywords: Science & Technology
Physical Sciences
Astronomy & Astrophysics
Physics, Particles & Fields
Physics
PROBE WMAP OBSERVATIONS
GLOBAL TEXTURE
EFFICIENT
NEEDLETS
SPOT
Science & Technology
Physical Sciences
Astronomy & Astrophysics
Physics, Particles & Fields
Physics
PROBE WMAP OBSERVATIONS
GLOBAL TEXTURE
EFFICIENT
NEEDLETS
SPOT
astro-ph.CO
astro-ph.CO
gr-qc
hep-th
Publication Status: Published
Article Number: 043012
Online Publication Date: 2013-08-26
Appears in Collections:Physics
Astrophysics



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commons