A note on Gravitational radiation in generalized Brans-Dicke theory: compact binary systems

TL;DR

This paper revises previous constraints on Brans-Dicke coupling parameters using binary system data, clarifying the role of scalar field mass in gravitational radiation within generalized Brans-Dicke theories.

Contribution

It corrects earlier bounds on the Brans-Dicke parameter and analyzes the impact of scalar field mass on gravitational radiation constraints.

Findings

Revised lower bounds on the Brans-Dicke coupling parameter $oldsymbol{\omega_0}$.

Identified the issue causing inverted constraints in previous analyses.

Showed the dependence of bounds on the scalar field mass $oldsymbol{m_f}$.

Abstract

This note revisits and corrects a previous analysis on gravitational radiation in compact binary systems within the framework of Brans-Dicke-f(R) theories-models featuring both massless and effectively massive scalar fields. We correct the lower bound on the Brans-Dicke coupling parameter $\omega_0$ presented in prior work, identifying teh issue that led to inverted constraints. By reanalyzing data from the binary system PSR J1012+5307, we present revised bounds on $\omega_0$ as a function of the geometrical scalar field mass $m_f$, emphasizing that the role of $\omega_0$ differs from its traditional interpretation in standard BD theory.