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arXiv · hep-ph/9311300

Supersymmetry and Light Quark Masses in a Realistic Superstring Model

Edi Halyo
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Abstract

We examine the light quark masses in a standard--like superstring model in the four dimensional free fermionic formulation. We find that the supersymmetry constraints in the observable and hidden sectors eliminate all large contributions to $m_u$ and $m_d$ and force them to be much smaller than the other quark masses. The requirement for an acceptable Higgs doublet spectrum results in $m_u<<m_d$. In these models a realistic $m_d$ can always be obtained whereas $m_u$ is at most $10^{-5}~MeV$. For particular choices of flat directions or vacua $m_u$ can be as small as $10^{-7}~MeV$ but cannot vanish.

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Edi Halyo. 1993-11-16. Supersymmetry and Light Quark Masses in a Realistic Superstring Model. https://doi.org/10.1016/0550-3213(94)90087-6

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