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arXiv · 2103.07204

A New Measurement of the Spin and Orbital Parameters of the High Mass X-ray Binary Centaurus X-3 using AstroSat

Parisee Shirke·Suman Bala·Jayashree Roy·Dipankar Bhattacharya
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Abstract

We present the timing results of out-of-eclipse observations of Centaurus X-3 spanning half a binary orbit, performed on 12-13 December, 2016 with the Large Area X-ray Proportional Counter (LAXPC) on-board AstroSat. The pulse profile was confirmed to exhibit a prominent pulse peak with a secondary inter-pulse. The systemic spin period of the pulsar was found to be $4.80188 \pm 0.000085$ s in agreement with its spin up trend. The spin up timescale seems to have increased to $7709 \pm 58$ yr that points to negative torque effects in the inner accretion disk. We also report the derived values of projected semi-major axis and orbital velocity of the neutron star.

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Parisee Shirke, Suman Bala, Jayashree Roy, Dipankar Bhattacharya. 2021-03-12. A New Measurement of the Spin and Orbital Parameters of the High Mass X-ray Binary Centaurus X-3 using AstroSat. https://doi.org/10.1007/s12036-021-09710-w

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