2018/08/31 by Hector O. Silva, Nicolás Yunes
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics #Classical mechanics #Curvature #Gamma-ray bursts and supernovae #General relativity #Geometry #Gravitation #Gravitational field #Neutron star #Physics #Pulsars and Gravitational Waves Research #Pulse (music) #Quantum mechanics #Scalar (mathematics) #Scalar field #astro-ph.HE #gr-qc
paper · pdf · doi:10.1103/physrevd.99.044034
published as Phys. Rev. D 99, 044034 (2019) · 15 pages, 8 figures; v2. updated to match published version
openalex publication_date 2019/02/19 · arxiv created 2019/02/27 · arxiv updated 2019/03/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
The observation of the x-ray pulse profile emitted by hot spots on the surface of neutron stars offers a unique tool to measure the bulk properties of these objects, including their masses and radii. The x-ray emission takes place at the star's surface, where the gravitational field is strong, making these observations an incise probe to examine the curvature of spacetime generated by these stars. Motivated by this and the upcoming data releases by x-ray missions, such as NICER (Neutron star Interior Composition Explorer), we present a complete toolkit to model pulse profiles of rotating neutron stars in scalar-tensor gravity. We find that, in this class of theories, the presence of the scalar field affects the pulse profile's overall shape, producing strong deviations from the general relativity expectation. This finding opens the possibility of potentially using x-ray pulse profile data to obtain new constraints on scalar-tensor gravity if the pulse profile is found to be in agreement with general relativity.