ABSTRACT This work is devoted to the study of broad-band 0.8–79 keV spectral and timing properties poorly studied X-ray pulsar XTE J1859+083 during its 2015 outburst based on data from NuSTAR Swift observatories. We show that source pulse profile has complex shape depends energy band. Pulse fraction constant value around 35 per cent in broad band, this behaviour atypical for pulsars. At same ti...