NuSTAR observation of X-ray pulsar 1E 1145.1-6141

In this paper, we report on the hard X-ray observation of the X-ray pulsar 1E 1145.1-6141 performed with the Nuclear Spectroscopic Telescope Array mission (NuSTAR). The coherent pulsation of the source with a period of $\sim 296.653\pm 0.021s$ is detected. The source may be in the equilibrium phase, according to the most recent measurements of its pulse period. The pulse profile reveals a mild energy dependence and generally hints at a pencil-beam pattern. The pulse profile have evolved with time. The Pulse fraction is found to depend on energy with a fall in the value at $\sim 32keV$. The NuSTAR spectra can be approximated by a composite model with two continuum components, a blackbody emission, cut-off powerlaw, and a discrete component in the form of gaussian to account for the emission line of iron. The estimated absorbed flux of the source is $\sim 6\times {10}^{-10}ergc{m}^{-2}{s}^{-1}$ which corresponds to a luminosity of $\sim 5\times {10}^{36}erg{s}^{-1}$. Pulse phase-resolved spectroscopy were performed to understand the evolution of spectral parameters with pulse phase. The estimated blackbody radius is found to be consistent with the size of the theoretical prediction.