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Title: Prospecting for new physics in the Higgs and flavor sectors

We explore two directions in beyond the standard model physics: dark matter model building and probing new sources of CP violation. In dark matter model building, we consider two scenarios where the stability of dark matter derives from the flavor symmetries of the standard model. The first model contains a flavor singlet dark matter candidate whose couplings to the visible sector are proportional to the flavor breaking parameters. This leads to a metastable dark matter with TeV scale mediators. In the second model, we consider a fully gauged SU(3)3 flavor model with a flavor triplet dark matter. Consequently, the dark matter multiplet is charged while the standard model fields are neutral under a remnant Z3 which ensures dark matter stability. We show that a Dirac fermion dark matter with radiative splitting in the multiplet must have a mass in the range [0:5; 5] TeV in order to satisfy all experimental constraints. We then turn our attention to Higgs portal dark matter and investigate the possibility of obtaining bounds on the up, down, and strange quark Yukawa couplings. If Higgs portal dark matter is discovered, we find that direct detection rates are insensitive to vanishing light quark Yukawa couplings. We then review flavor models and give the expected enhancement or suppression of the Yukawa couplings in those models. Finally, in the last two chapters, we develop techniques for probing CP violation in the Higgs coupling to photons and in rare radiative decays of B mesons. While theoretically clean, we find that these methods are not practical with current and planned detectors. However, these techniques can be useful with a dedicated detector (e.g., a gaseous TPC). In the case of radiative B meson decay B0 → (K* → Kππ) γ, the techniques we develop also allow the extraction of the photon polarization fraction which is sensitive to new physics contributions since, in the standard model, the right(left) handed polarization fraction is of O( ΛQCD=mb) for $$\bar{B}^{0}$$(B0) meson decays.
Authors:
 [1]
  1. Univ. of Cincinnati, OH (United States)
Publication Date:
OSTI Identifier:
1212175
Report Number(s):
FERMILAB-THESIS--2015-10
TRN: US1601302
DOE Contract Number:
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; B NEUTRAL MESONS; FLAVOR MODEL; RADIATIVE DECAY; NONLUMINOUS MATTER; HIGGS MODEL; C QUARKS; D QUARKS; S QUARKS; U QUARKS; HIGGS BOSONS; CP INVARIANCE; KAONS; PIONS; PHOTONS; TEV RANGE; COUPLINGS; SYMMETRY BREAKING; POLARIZATION; PROBES; STABILITY; TRIPLETS; LIMITING VALUES; DETECTION; INHIBITION; MASS; SYMMETRY; SU-3 GROUPS; YUKAWA NONLOCAL THEORY