Non-tachyonic open descendants of the 0B string theory

TL;DR

This paper constructs non-tachyonic open string descendants of the 0B string theory compactified on specific orbifolds, resulting in consistent models with chiral fermions and particular gauge groups in four dimensions.

Contribution

It introduces a method using the crosscap constraint to build tachyon-free open descendants of the 0B string on orbifolds, with explicit gauge groups and chiral matter content.

Findings

Tachyon-free open string models on $T^6/Z_3$ and $T^4/Z_2$.

Chiral fermions with three generations in the constructed models.

Specific gauge group $U(8) imes U(12) imes U(12)$ in four dimensions.

Abstract

We use the crosscap constraint to construct open descendants of the 0B string compactified on $T^6 /Z_3$ and on $T^4/Z_2$ free of tachyons both in the closed and in the open unoriented sectors. In four dimensions the construction results in a Chan-Paton gauge group $U(8)\otimes U(12)\otimes U(12)$ with three generations of chiral fermions in the representations $(\overline{8},1,\overline{12}) +(8,12,1)+(1,\overline{66},1)+(1,1,66)$.