We report results of the spectral and timing analysis of the Be/X-ray pulsar SXP 4.78 using the data obtained during its recent outburst with NuSTAR , Swift , Chandra and NICER observatories .
Using an overall evolution of the system luminosity , spectral analysis and variability power spectrum we obtain constraints on the neutron star magnetic field strength .
We found a rapid evolution of the variability power spectrum during the rise of the outburst , and absence of the significant changes during the flux decay .
Several low frequency quasi-periodic oscillation features are found to emerge on the different stages of the outburst , but no clear clues on their origin were found in the energy spectrum and overall flux behaviour .
We use several indirect methods to estimate the magnetic field strength on the neutron star surface and found that most of them suggest magnetic field B \lesssim 2 \times 10 ^ { 12 } G. The strictest upper limit comes from the absence of the cyclotron absorption features in the energy spectra and suggests relatively weak magnetic field B < 6 \times 10 ^ { 11 } G .