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tokens: ~ 2–3 × 10 12 G) magnetic field strength of SMC X-3 and for cm ( Ghosh et al. 1977 ; Ghosh Lamb 1979a , b , 1992 ), where α is a constant that depends on the geometry of the accretion flow, with α = 0.5 the commonly used value for disk accretion, Ṁ 15 is the mass accretion rate in units of 10 15 g s −1 (estimated for the observed luminosity of ~ 1.5 × 10 38 erg s −1 and assuming an efficiency of 0.2), B 9 is the NS magnetic field in units of 10 9 G, M 1.4 is the NS mass in units of 1.4 times the solar mass, and R 6 is the NS radius in units of 10 6 cm. Three prominent broad emission lines are featured on top of the broadband continuum. Centered at ~ 0.51 keV, ~ 0.97 keV, and ~ 6.64 keV, the lines are consistent with emission from hot ionized plasma. The 6.6 keV line is most likely due to K-shell fluorescence from highly ionized iron, while the 0.5 keV line is most likely the K α line of the N VII – Ly α (500) ion. The 1 keV line is most likely the result of combined Ne K α and Fe L-shell emission lines. Both the 1 keV and 6.6 keV lines appear to be broadened, although as we discuss below, the broadening is most likely artificial and is the result of blending of unresolved emission lines from relevant atoms at different ionization states. Both the 1 kev and the 6.6 keV lines are often detected in the spectra of XRBs and appear to be particularly pronounced in the spectra of X-ray pulsars (e.g., Boirin Parmar 2003 ; Díaz Trigo et al. 2006 ; Ng et al. 2010 ; Kolehmainen et al. 2014 ). While in many XRBs the emission lines (and particularly the iron K α line) are attributed to reflection of the primary emission from the optically thick accretion disk (e.g., Gilfanov 2010 , and references therein), in the case of X-ray pulsars (and in this source), the emission line origin is more consistent with optically thin emission from rarefied hot plasma that is trapped in the Alfvén shell of the highly magnetized NS (e.g., Basko 1978 ). The (apparent) line broadening is consistent with microscopic processes, i.e., Compton scattering for a scattering optical depth of 0.5–1 (e.g., Eq. (30) in Basko 1978 ), rather than macroscopic motions, such as the rotation of the accretion disk or the surface of the donor star. The measured width of the two lines corresponds to line-of-sight velocities of ~ 1.6 × 10 4 km s −1 . For the disk inclination of ≲45°, expected for SMC X-3 ( Townsend et al. 2017 ), this corresponds to a 3D velocity of ≳ 2.3 × 10 4 km s −1 . Assuming Keplerian rotation, these velocities would correspond to a distance of ≲ 350 km from the NS, which is almost an order of magnitude smaller than the estimated magnetospheric radius. Furthermore, the phase-resolved pn spectra and the RGS spectra (discussed below) indicate that the line broadening may be an artifact, resulting from the blending of unresolved thin emission lines at different centroid energies. 4.3 Short-term evolution of the spectral continuum and emission lines The timing analysis of