Abstract Accreting X-ray pulsars (XRPs) undergo luminous outbursts during which the spectral and timing behavior of neutron star can be studied in detail. We analyze a NuSTAR observation XRP XTE J1858+034 its outburst 2019. The spectrum is fit with phenomenological, semiempirical, physical model. A candidate cyclotron line found at 48 keV, implying magnetic field 5.4 × 10 12 G site emission. Th...