The One-Loop H^2R^3 and H^2(DH)^2R Terms in the Effective Action

TL;DR

This paper analyzes one-loop string amplitudes to identify specific higher-derivative terms in the effective action involving the NS-NS two-form and graviton fields, revealing their structure and coefficients.

Contribution

It determines the explicit form and structure of H^2R^3 and H^2(DH)^2R terms in the one-loop effective action of type II string theory, including their multiplicative factors.

Findings

Identified H^2R^3 and H^2(DH)^2R terms in the effective action.

Both terms are multiplied by the (t_8t_8 ± 1/8 ε_{10}ε_{10}) factor.

Confirmed the structure of these terms at one-loop order.

Abstract

We consider the one-loop B^2h^3 and B^4h amplitudes in type II string theory, where B is the NS-NS two-form and h the graviton, and expand to lowest order in alpha'. After subtracting diagrams due to quartic terms in the effective action, we determine the presence and structure of both an H^2R^3 and H^2(DH)^2R term. We show that both terms are multiplied by the usual (t_8t_8\pm{1/8}\epsilon_{10}\epsilon_{10}) factor.