Year: 2008
Type: article
Abstract: We calculate the strength of the electroweak phase transition in a supersymmetric model with four chiral generations. The additional chiral fermions (and scalar partners) lower the critical temperature and thus strengthen the first-order phase transition. The scalar partners stabilize the potential, leading to an effective theory that is bounded from below. We identify the ensemble of parameters where ${\ensuremath{\phi}}_{c}/{T}_{c}\ensuremath{\gtrsim}1$ simultaneous with obtaining a large enough Higgs mass. Our calculations focus on a subset of the full four generational supersymmetric parameter space: We take the pseudoscalar heavy, $\mathrm{tan}\ensuremath{\beta}=1$, and neglect all subleading contributions to the effective potential. We find that the region of parameter space with a strong first-order phase transition requires ${m}_{{\stackrel{\texttildelow{}}{q}}^{\ensuremath{'}}}/{m}_{{q}^{\ensuremath{'}}}\ensuremath{\lesssim}1.1$ while the constraint on the lightest Higgs mass requires ${m}_{{\stackrel{\texttildelow{}}{q}}^{\ensuremath{'}}}/{m}_{{q}^{\ensuremath{'}}}\ensuremath{\gtrsim}1$ with ${m}_{{q}^{\ensuremath{'}}}\ensuremath{\gtrsim}300\text{ }\text{ }\mathrm{GeV}$. We are led to an intriguing prediction of quarks and squarks just beyond the current Tevatron direct search limits that are poised to be discovered quickly at the LHC.
Authors: Ricky Fok, Graham D. Kribs
Institution: University of Oregon
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: U.S. Department of Energy, CERN
OpenAlex ID: W2001560451