Open Access Dissertation
Date of Award
Physics and Astronomy
This dissertation describes two topics in high-energy physics. In the first we describe the
extraction of the magnetic radius of the proton. In the second we impose LHC constraints on
the combined anomaly and Z’ mediation mechanisms of supersymmetry breaking.
We combine constraints from analyticity with experimental electron-proton scattering data
to determine the proton magnetic radius without model-dependent assumptions on the shape
of the form factor. We also study the impact of including electron-neutron scattering data,
and ππ ! NN¯ data. Using representative datasets we find for a cut of Q2 ≤ 0:5 GeV2,
−0:06 ± 0:02 fm using just proton scattering data; rMp = 0:87+0 −0: :04 05 ± 0:01 fm adding
neutron data; and rMp = 0:87+0 −0: :02 02 fm adding ππ data. We also extract the neutron magnetic
radius from these data sets obtaining rMn = 0:89+0 −0: :03 03 fm from the combined proton, neutron,
and ππ data. Particle Data Group (PDG) has reported both of these values, rMp = 0:87 ± 0:02
fm and rn
M = 0:89 ± 0:03 fm in their 2016 listing of the magnetic radius of the proton and
Combining anomaly with Z0 mediation allows us to solve the tachyonic problem of the
former and avoid fine tuning in the latter. This model includes an extra U(1)0 gauge symmetry
and extra singlet scalar S which provides a solution to the ‘µ problem’ of the MSSM. The
low-energy particle spectrum is calculated from the UV inputs using the Renormalization
Group Equations. The benchmark points considered in the original model, suggested before
the Higgs discovery, predicted a Higgs mass close to the current measured value of 125 GeV.
We use the current LHC data to update the predictions of the model, its particle spectrum
and in particular the mass of the Z0 gauge boson.
Roy, Joydeep, "Topics In High-Energy Physics: The Proton Magnetic Radius And Phenomenology Of Z0 Mediation Of Supersymmetry Breaking" (2017). Wayne State University Dissertations. 1866.