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D12a-4Be1-A0c8-2707De442dbb.Txt Dépôt Institutionnel de l’Université libre de Bruxelles / Université libre de Bruxelles Institutional Repository Thèse de doctorat/ PhD Thesis Citation APA: Lopez Honorez, L. (2007). Dark matter: signs and genesis (Unpublished doctoral dissertation). Université libre de Bruxelles, Faculté des Sciences – Physique, Bruxelles. Disponible à / Available at permalink : https://dipot.ulb.ac.be/dspace/bitstream/2013/210692/4/e07112e3-d12a-4be1-a0c8-2707de442dbb.txt (English version below) Cette thèse de doctorat a été numérisée par l’Université libre de Bruxelles. L’auteur qui s’opposerait à sa mise en ligne dans DI-fusion est invité à prendre contact avec l’Université ([email protected]). Dans le cas où une version électronique native de la thèse existe, l’Université ne peut garantir que la présente version numérisée soit identique à la version électronique native, ni qu’elle soit la version officielle définitive de la thèse. 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D 03486 Université Libre de Bruxelles Faculté des Science Service de Physique Théorique Dark Matter SiGNS AND GENESIS Thèse présentée en vue de l’obtention du Grade Légal de Docteur en Sciences Physique Laura Lopez Honorez Mai 2007 Université Libre de Bruxelleb 0033BB021 Université Libre de Bruxelles Faculté des Science Service de Physique Théorique Dark Matter SiGNS AND GENESIS Thèse présentée en vue de l’obtention du Grade Légal de Docteur en Sciences Physique Laura LoPEZ Honorez Mai 2007 1 Contents Table of contents iii Abbreviation List v Introduction 4 1 Dark matter tools 5 1.1 Friedman-Lemaître-Robertson-Walker model .................................................. 5 1.2 The evidence for dark matter............................................................................. 7 1.3 Thermodynamics in the Early universe.............................................................. 9 1.3.1 Boltzmann équations................................................................................. 10 1.3.2 Annihilations and relie abundance: approximate solution ................. 12 1.3.3 Coannihilation.......................................................................................... 15 1.4 History of the universe.......................................................................................... 17 1.4.1 Thermal History of the universe.............................................................. 17 1.4.2 Add-on to Big Bang Cosmology; Baryogenesis...................................... 25 2 Constraints on dark matter and some particle physics candidates 31 2.1 Constraints from Direct and Indirect détection ............................................... 31 2.1.1 Direct Détection....................................................................................... 32 2.1.2 Indirect détection....................................................................................... 34 2.2 Constraint from unitarity .................................................................................... 36 2.3 Hot and Cold dark matter: distinction from structure formation................... 38 2.3.1 Jeans length and free streaming length.................................................. 38 2.3.2 The power spectrum................................................................................. 40 2.3.3 The “Standard Model” neutrino: a hot dark matter candidate .... 42 2.3.4 The WIMPs from the MSSM: popular cold dark matter candidates 44 3 The Inert Doublet Model 47 3.1 The model................................................................................................................ 49 3.1.1 Scalar potential ....................................................................................... 49 3.1.2 Constraints................................................................................................ 50 3.2 Dark Matter abundance....................................................................................... 51 3.3 Inert scalars détection.......................................................................................... 53 3.3.1 Indirect détection....................................................................................... 53 3.3.2 Direct détection.......................................................................................... 54 3.3.3 Détection at colliders ?.............................................................................. 55 3.4 Analysis of the IDM............................................................................................. 56 CONTENTS 3.4.1 Low mass régime, Mhq around Mw .................................................... 57 3.4.2 The high mass régime, Mfj » Mw....................................................... 60 3.5 Concluding discussion on the IDM.................................................................. 63 4 MeV right-handed neutrîno as dark matter 69 4.1 The L-R symmetric model ................................................................................ 70 4.2 Constraints............................................................................................................ 73 4.2.1 Stability of the right-handed neutrinos................................................. 74 4.2.2 Constraint on the decay rate from INTEGRAL and COMPTEE ... 75 4.2.3 Constraints from neutrino experiments................................................. 77 4.3 Cosmological abundance ; low reheating température scénario..................... 79 4.4 The link with Intégral ?...................................................................................... 82 4.4.1 The 511 keV signal ................................................................................ 82 4.4.2 Light dark matter annihilation as a source for positrons.................. 84 4.4.3 The MeV right-handed neutrino at the origin of the 511 keV signal? 86 4.5 Concluding discussion on MeV right handed neutrino .................................. 87 5 Matter Genesis Mechanism 89 5.1 The Model............................................................................................................... 90 5.1.1 Symmetry breaking and Residual Z2 symmetry.................................. 91 5.1.2 Fermion masses......................................................................................... 92 5.1.3 Gauge boson masses................................................................................ 93 5.2 The Matter Genesis mechanism.......................................................................... 93 5.2.1 Initial B-L asymmetry............................................................................. 94 5.2.2 Annihilation of the messengers and first
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