Exploring β-symmetry in heterotic theory at order α′ with boundary term.

This paper investigates the β-symmetry of the heterotic string theory at order α′ in the context of open spacetime manifolds. Our analysis reveals that the parity-odd component of the effective action at this order remains invariant under β-transformations. Furthermore, we demonstrate that the corresponding β-transformations leave the Gibbons-Hawking boundary term invariant. [ABSTRACT FROM AUTHOR]