Study of the X-ray Pulsar IGR J21343+4738 Based on NuSTAR, Swift, and SRG Data

We present the results of our study of the X-ray pulsar IGR J21343+4738 based on NuSTAR, Swift, and SRG observations in the wide energy range 0.3-79 keV. The absence of absorption features in the energy spectra of the source, both averaged and phase-resolved ones, has allowed us to estimate the upper and lower limits on the magnetic field of the neutron star in the binary system, $B<2.5× 10^{11}$ and $B>3.4× 10^{12}$ G, respectively. Our spectral and timing analyses have shown that IGR J21343+4738 has all properties of a quasi-persistent X-ray pulsar with a pulsation period of $322.71±{0.04}$ s and a luminosity $L_x∼eq 3.3× 10^{35}$ erg s${}^{-1}$. Our analysis of the long-term variability of the object in X-rays has confirmed the possible orbital period of the binary system ${∼}34.3$ days previously detected in the optical range.