Skip to Main content Skip to Navigation
Journal articles

First measurement of the total gravitational quadrupole moment of a black widow companion

Abstract : We present the first measurement of the gravitational quadrupole moment of the companion star of a spider pulsar, namely the black widow PSR J2051$-$0827. To this end we have re-analysed radio timing data using a new model which is able to account for periastron precession caused by tidal and centrifugal deformations of the star as well as by general relativity. The model allows for a time-varying component of the quadrupole moment, thus self-consistently accounting for the ill-understood orbital period variations observed in these systems. Our analysis results in the first detection of orbital precession in a spider system at $\dot{\omega} = -68.6_{-0.5}^{+0.9}$ deg/yr and the most accurate determination of orbital eccentricity for PSR J2051$-$0827 with $e = (4.2 \pm 0.1) \times 10^{-5}$. We show that the variable quadrupole component is about 100 times smaller than the average quadrupole moment $\bar{Q} = -2.2_{-1}^{+0.6} \times 10^{41} \si{kg.m^2}$ . We discuss how accurate modelling of high precision optical light curves of the companion star will allow its apsidal motion constant to be derived from our results.
Complete list of metadatas

Cited literature [44 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-02427662
Contributor : Guillaume Voisin <>
Submitted on : Thursday, April 2, 2020 - 12:33:19 PM
Last modification on : Saturday, April 11, 2020 - 1:56:47 AM

Identifiers

  • HAL Id : hal-02427662, version 2
  • ARXIV : 2004.01564

Collections

Citation

Guillaume Voisin, C Clark, R Breton, V. Dhillon, M Kennedy, et al.. First measurement of the total gravitational quadrupole moment of a black widow companion. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, In press, 000, pp.1 - 5. ⟨hal-02427662v2⟩

Share

Metrics

Record views

23

Files downloads

20