Intersections of Astrophysics, Cosmology and Particle Physics Luiz Henrique Moraes Da Silva University of Wisconsin-Milwaukee
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University of Wisconsin Milwaukee UWM Digital Commons Theses and Dissertations May 2016 Intersections of Astrophysics, Cosmology and Particle Physics Luiz Henrique Moraes da Silva University of Wisconsin-Milwaukee Follow this and additional works at: https://dc.uwm.edu/etd Part of the Physics Commons Recommended Citation da Silva, Luiz Henrique Moraes, "Intersections of Astrophysics, Cosmology and Particle Physics" (2016). Theses and Dissertations. 1132. https://dc.uwm.edu/etd/1132 This Dissertation is brought to you for free and open access by UWM Digital Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of UWM Digital Commons. For more information, please contact [email protected]. INTERSECTIONS OF ASTROPHYSICS, COSMOLOGY AND PARTICLE PHYSICS by Luiz Henrique Moraes da Silva A Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Physics at University of Wisconsin-Milwaukee May 2016 ABSTRACT INTERSECTIONS OF ASTROPHYSICS, COSMOLOGY AND PARTICLE PHYSICS by Luiz Henrique Moraes da Silva The University of Wisconsin-Milwaukee, 2016 Under the Supervision of Professor Anchordoqui and Professor Raicu With the success of the Large Hadron Collider (LHC) at CERN, a new era of discovery has just begun. The SU(3)C ×SU(2)L ×U(1)Y Standard Model (SM) of electroweak and strong interactions has once again endured intensive scrutiny. Most spectacularly, the recent discovery of a particle which seems to be the SM Higgs has possibly plugged the final remaining experimental hole in the SM, cementing the theory further. Adding more to the story, the IceCube Collaboration recently reported the discovery of extraterrestrial neutrinos, heralding a new era in astroparticle physics. The collaboration was able to isolate 36 events in 3 years of data, with energies between 30 TeV . Eν . 2 PeV. These events are consistent with an isotropic distribution in the sky, and a purely atmospheric explanation of the data can be excluded at 5.7σ. However, problems still exist. Cosmological observations concerning dark matter and the expansion rate of the Universe have shown us our picture of the basic constituents of the Universe and the interactions among them are not fully understood. In addition, the determination of the origin of high energy neutrinos has proven to be a quite formidable problem, with many possible candidates for sources. Motivated by these problems, we study and impose constraints on a dark matter model, and consider the idea of starburts and Galatic microquasars as possible astrophysical sources for the high energy neutrino events observed at IceCube. In addition, dark matter decay is considered as a way to explain high-energy neutrino events and reconcile the tension between measurements of the Hubble constant by different observation methods. ii TABLE OF CONTENTS List of Figures viii List of Tables xiii Acknowledgements xiv 1 Introduction 1 1.1 Natural Units . 5 2 U(1)Y × SU(2)L × SU(3)C 6 2.1 Historical Introduction . 6 2.2 Canonical Quantization . 7 2.2.1 The Harmonic Oscillator . 7 2.2.2 Canonical quantization of scalar fields . 8 2.2.3 The Pauli exclusion principle . 13 2.2.4 Canonical quantization of spin-half fields . 14 2.3 Symmetry breaking . 15 2.3.1 The Abelian case and the Goldstone Theorem . 15 2.3.2 Symmetry breaking with a non-Abelian group . 18 2.4 The Standard Model of Particle Physics . 20 2.4.1 The Electroweak sector . 20 2.4.2 Leptons and Quarks . 28 3 Elementary Topics in Quantum Field Theory 35 3.1 Non-relativistic perturbation theory . 35 3.2 Invariant amplitude . 40 3.3 Decay rates and cross-sections . 40 3.4 VEV's, path integrals and matrix elements . 49 3.5 Quantum Electrodynamics . 54 3.6 A comment on renormalization . 61 iii 4 Electroweak Physics 63 4.1 Super selection rules, CPT and violations . 63 4.1.1 Super selection rules . 63 4.1.2 The CPT theorem . 64 4.1.3 Violations . 69 4.2 Weak currents . 69 4.3 Neutrino flavor mixing . 73 4.4 Parity violation and helicity . 77 4.5 The Glashow resonance . 82 5 Cosmology 84 5.1 The Homogeneous, Isotropic Universe . 84 5.2 An overview of the physics in the Early Universe . 92 5.2.1 The first moments . 93 5.2.2 An overview of Thermodynamics . 96 5.2.3 Degrees of freedom . 102 5.2.4 The Boltzmann equation . 104 5.3 Dark matter, dark energy and the ΛCDM model . 107 5.3.1 Observational evidence . 107 5.3.2 The Planck spacecraft and cosmological parameters . 108 6 Beyond the Standard Model 110 6.1 Introduction . 110 6.2 Minimal Higgs Portal Model . 112 6.3 Constraints from experiment . 118 6.3.1 Constraints from direct DM searches . 118 6.3.2 Constraints from heavy meson decay . 122 6.3.3 Constraints from LHC and SN1987A . 123 6.3.4 Constraints from cosmology . 125 6.4 RG Evolution Equations . 128 iv 6.5 Vacuum Stability Constraints . 129 6.5.1 Light scalar singlet . 129 6.5.2 Heavy scalar singlet . 131 6.6 Conclusions . 136 7 Astrophysical Neutrino Production and multi-messenger search 138 7.1 Astrophysical accelerators . 138 7.2 Proton-proton, proton-photon interactions . 141 7.3 Particle decays . 143 7.4 On the astrophysical flavor ratio . 147 7.5 Solar and atmospheric neutrinos . 148 7.6 Neutrinos and Cosmic Rays . 149 7.6.1 The Waxman - Baccal bound . 149 7.6.2 γ-rays and Fermi - LAT . 150 8 The IceCube experiment 151 8.1 An overview of the experiment . 151 8.1.1 Next generations and upgrades . 151 8.2 Cherenkov radiation . 152 8.3 Cross sections for interactions at the detector . 152 8.4 Neutrino tracks . 154 8.5 Event maps . 156 9 Looking for high energy neutrino sources 158 9.1 Astrophysical sources: Galactic microquasars . 158 9.1.1 IceCube neutrinos as the smoking ice of LS 5039 engine . 160 9.1.2 Generalities of the microquasar population in the Galaxy . 166 9.1.3 High energy Neutrinos from Galactic microquasars . 169 9.1.4 Constraints from gamma rays and baryonic cosmic rays . 175 9.1.5 Final remarks . 176 9.2 Astrophysical sources: Starbursts . 178 v 9.3 Insufficiencies of astrophysical models . 186 10 Reconciling the Hubble constant measurements 187 10.1 Decaying dark matter and the Hubble parameter . 187 10.1.1 Connecting the dots . 188 10.1.2 Bump-Hunting . 189 References 197 11 Appendix A - 4-momentum and Mandelstam variables 226 11.1 Special Relativity . 226 11.2 4-momentum . 238 11.3 Mandelstam variables . 242 12 Appendix B - Gauge Theories 246 12.1 Gauging the symmetry . 246 12.2 Yang- Mills Theory . 254 12.2.1 The non-Abelian case . 254 12.3 Gravity . 258 12.3.1 Gravity as a Gauge Theory . 259 12.3.2 The metric and the Levi-Civita connection . 262 12.3.3 Killing vector fields and Lie algebras . 264 13 Appendix C - Gamma matrices 269 13.1 Dirac representation . 269 13.2 Identities . 270 13.3 Traces . 270 14 Appendix D - Effective coupling 272 15 Appendix E - Obtaining RG equations 273 16 Appendix F - Stability 276 vi 17 Curriculum Vitae 279 17.1 Research Experience . 279 17.2 Education . 279 17.3 Refereed Journal Publications . 279 17.4 Conference Talks . 280 17.5 Awards . 280 vii LIST OF FIGURES 1 Potential before and after symmetry breaking . 16 2 Feynman diagrams at tree level for the Compton scattering. 60 3 Charged Current (CC) . 72 4 Weak interaction . 79 5 The relation in Eq. (510). 120 6 Excluded regions of the (j θ j; mh) parameter space from interactions in- volving SM particles in the initial state and the CP -even scalar in the final state, as well from DM direct detection experiments. The horizontal bands indicate bounds are from heavy meson decays with missing energy (no sig- nificant excess of such decays over background has been observed yielding bounds on the processes Υ ! γh; B+ ! K+h; K+ ! π+h) as well as from LEP limits on the production of invisibly-decaying Higgs bosons σZh/σZH . The diagonal bands represent bounds from DM direct detection experiments (Super-CDMS and LUX), for different values of the WIMP mass. Note that all bounds other than the LEP bound can be smoothly extrapolated to the smallest mh ∼ 35MeV stipulated by cosmology. 122 0 7 Bounds on the (jθj; mh) including invisible Higgs decays and α emission in a post-collapse supernova core for different assumptions about the value of the quartic coupling λ2. 124 8 Comparison of vacuum stability requirements in the (θ; mh) plane (blue curve) with the upper limit set by SN1987A observations. 132 9 The red area shows the allowed parameter space in the mh2 vs. θ plane under the vacuum stability constraint of Eq. (482), with Λ =.