Tidal contributions to neutron star orbital precession around Sgr A*
Abstract
We investigate tidal contributions to the orbital precession of neutron stars around the supermassive black hole Sgr A*, using stellar configurations described by the Tolman - Oppenheimer - Volkoff equations. We examine the dependence of tidal precession on stellar compactness, pericentre distance, and the quadrupolar tidal Love number k2, and compare its magnitude with general relativistic orbital precession. The calculated tidal angular shift decreases strongly with increasing pericentre distance and, for the stellar configurations considered, with increasing compactness. Larger Love numbers enhance the tidal contribution. This behaviour reflects the strong dependence of tidal precession on the stellar-radius-to-pericentre-distance ratio, (R/rp)5. Despite the enhancement during closer encounters, the predicted tidal shifts remain extremely small, reaching approximately 3.5 × 10−18,μas within the displayed parameter range. The ratio of tidal to general relativistic precession spans approximately 10−33 - 10−28, indicating that relativistic precession overwhelmingly dominates. Our results suggest that direct detection of the neutron-star tidal contribution through orbital precession around Sgr A* would be exceptionally challenging under the assumptions of the adopted model.
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BibTeX
@misc{lalrinfela2026tidal,
title = {{Tidal contributions to neutron star orbital precession around Sgr $A^*$}},
author = {H Lalrinfela and P. C. Lalremruati and Zodinmawia and N Malsawmtluangi},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.35776},
eprint = {2610.35776},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.35776},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Tidal contributions to neutron star orbital precession around Sgr A^*
AU - H Lalrinfela
AU - P. C. Lalremruati
AU - Zodinmawia
AU - N Malsawmtluangi
PY - 2026
DA - 2026/10/26
PB - arXiv
DO - 10.48550/arxiv.2610.35776
UR - https://arxiv.org/abs/2610.35776
AB - We investigate tidal contributions to the orbital precession of neutron stars around the supermassive black hole Sgr A*, using stellar configurations described by the Tolman - Oppenheimer - Volkoff equations. We examine the dependence of tidal precession on stellar compactness, pericentre distance, and the quadrupolar tidal Love number k_2, and compare its magnitude with general relativistic orbital precession. The calculated tidal angular shift decreases strongly with increasing pericentre distance and, for the stellar configurations considered, with increasing compactness. Larger Love numbers enhance the tidal contribution. This behaviour reflects the strong dependence of tidal precession on the stellar-radius-to-pericentre-distance ratio, (R/r_p)^5. Despite the enhancement during closer encounters, the predicted tidal shifts remain extremely small, reaching approximately 3.5 × 10^−18,μas within the displayed parameter range. The ratio of tidal to general relativistic precession spans approximately 10^−33 - 10^−28, indicating that relativistic precession overwhelmingly dominates. Our results suggest that direct detection of the neutron-star tidal contribution through orbital precession around Sgr A* would be exceptionally challenging under the assumptions of the adopted model.
ER -