Exploring the X-ray and gamma-ray properties of the redback millisecond pulsar PSR J1723-2837

Abstract

We have investigated the X-ray and $γ$-ray properties of the redback millisecond pulsar PSR J1723-2837 with XMM-Newton, Chandra and Fermi. We have discovered the X-ray orbital modulation of this binary system with the minimum that coincides with the phases of radio eclipse. The X-ray emission is clearly non-thermal in nature which can be well described by a simple power-law with a photon index of $\sim1.2$. The phase-averaged luminosity is $\sim9\times10^{31}$ erg/s in 0.3-10 keV which consumes $\sim0.2\%$ of the spin-down power. We have detected the $γ-$ray emission in $0.1-300$ GeV from this system at a significance of $\sim6σ$ for the first time. The $γ-$rays in this energy range consumes $\sim2\%$ of the spin-down power and can be modeled by a power-law with a photon index of $\sim2.6$. We discuss the high energy properties of the new redback in the context of a intrabinary shock model.

13 pages, 3 figures, accepted for publication in ApJ Letter