A Light Z' Heterotic-String Derived Model

Understand

The existence of an extra Z' inspired from heterotic-string theory at accessible energy scales attracted considerable interest in the particle physics literature.

• Surprisingly, however, the construction of heterotic--string derived models that allow for an extra Z' to remain unbroken down to low scales has proven to be very difficult.
• The main reason being that the U(1) symmetries that are typically discussed in the literature are either anomalous or have to be broken at a high scale to generate light neutrino masses.
• In this paper we use for that purpose the self duality property under the spinor vector duality, which was discovered in free fermionic heterotic-string models.