Detection of relativistic orbital deformation from improved timing of PSR J1757−1854
Abstract
PSR~J1757−1854, a 21.5\,ms pulsar, is a highly relativistic double neutron star (DNS) system in a tight eccentric (e = 0.61) 4.4\,hr orbit. With extremely large gravitational wave luminosity and one of the fastest orbital decay rates of any known DNS system, it is ideal for testing general relativity (GR) in the strong-field regime. Here we present results from a high-precision timing campaign combining archival data from the Murriyang telescope and Green Bank Telescope (GBT) with new high-sensitivity observations from the MeerKAT radio telescope and additional observations from the GBT. The extended baseline and superior sensitivity of MeerKAT have yielded substantial improvements to previously measured post-Keplerian parameters by a factor of around ∼2 or more. We report the first detection of the relativistic angular deformation, δθ in this system, making PSR~J1757−1854 only the third DNS system for which δθ has been measured, achieved here in just 9 yrs compared to the decades of timing required for both the double pulsar and the Hulse-Taylor binary. We demonstrate how δθ can be used to constrain the spin-orbit geometry of the system, ruling out two of the four geometric solutions previously identified, while remaining consistent with GR. We also evaluate higher-order contributions to the periastron advance ω̇, including the second post-Newtonian correction and the Lense-Thirring term, and show that these have a measurable systematic effect on the inferred total system mass. The observed orbital period derivative, Ṗb remains consistent with the GR prediction for gravitational-wave damping across a wide range of plausible distances.
Versions
Related
- Complete Second-Order Relativistic Derivation of the Observed Pulsar Timing Modulations
- High-precision Relativistic Timescales for Mars Surface and Orbital Clocks
- High-Precision Relativistic Time Scales for Mars Surface and Orbital Clocks
- X-ray Comptonization in an Accreting Kerr Black Hole System with a Tilted Disc and Thermal Corona; A General-Relativistic Monte Carlo Simulation: I. Model, Radiative Transfer and Spectral-Timing Properties
- An improved self-gravity treatment in general relativistic smoothed particle hydrodynamics
BibTeX
@misc{singha2026detection,
title = {{Detection of relativistic orbital deformation from improved timing of PSR J1757$-$1854}},
author = {Jaikhomba Singha and Vivek Venkatraman Krishnan and Marisa Geyer and Victoria Blackmon and Paulo Freire and Norbert Wex and Maura McLaughlin and Michael Kramer and Amanda Weltman and David Champion and Matthew Bailes and Sarah Buchner and Fernando Camilo and Andrea Possenti and Maciej Serylak},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2606.23926},
eprint = {2606.23926},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2606.23926},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Detection of relativistic orbital deformation from improved timing of PSR J1757−1854
AU - Jaikhomba Singha
AU - Vivek Venkatraman Krishnan
AU - Marisa Geyer
AU - Victoria Blackmon
AU - Paulo Freire
AU - Norbert Wex
AU - Maura McLaughlin
AU - Michael Kramer
AU - Amanda Weltman
AU - David Champion
AU - Matthew Bailes
AU - Sarah Buchner
AU - Fernando Camilo
AU - Andrea Possenti
AU - Maciej Serylak
PY - 2026
DA - 2026/10/06
PB - arXiv
DO - 10.48550/arxiv.2606.23926
UR - https://arxiv.org/abs/2606.23926
AB - PSR~J1757−1854, a 21.5\,ms pulsar, is a highly relativistic double neutron star (DNS) system in a tight eccentric (e = 0.61) 4.4\,hr orbit. With extremely large gravitational wave luminosity and one of the fastest orbital decay rates of any known DNS system, it is ideal for testing general relativity (GR) in the strong-field regime. Here we present results from a high-precision timing campaign combining archival data from the Murriyang telescope and Green Bank Telescope (GBT) with new high-sensitivity observations from the MeerKAT radio telescope and additional observations from the GBT. The extended baseline and superior sensitivity of MeerKAT have yielded substantial improvements to previously measured post-Keplerian parameters by a factor of around ∼2 or more. We report the first detection of the relativistic angular deformation, δ_θ in this system, making PSR~J1757−1854 only the third DNS system for which δ_θ has been measured, achieved here in just 9 yrs compared to the decades of timing required for both the double pulsar and the Hulse-Taylor binary. We demonstrate how δ_θ can be used to constrain the spin-orbit geometry of the system, ruling out two of the four geometric solutions previously identified, while remaining consistent with GR. We also evaluate higher-order contributions to the periastron advance ω̇, including the second post-Newtonian correction and the Lense-Thirring term, and show that these have a measurable systematic effect on the inferred total system mass. The observed orbital period derivative, Ṗ_b remains consistent with the GR prediction for gravitational-wave damping across a wide range of plausible distances.
ER -