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We present the analysis of 200-ks NuSTAR observation of the Vela pulsar andthe pulsar wind nebula (PWN). The phase-resolved spectra corresponding to thetwo main peaks in the folded pulse profile differ significantly. The spectrumof Peak 1 is significantly harder than that of Peak 2 in qualitative agreementwith the earlier RXTE results. However, for both spectra, the best-fit valuesof photon indices for the power-law (PL) fit are noticeably larger than thepreviously reported values. The hardest (Peak 1) spectrum has a photon index of$1.10\pm0.15$ which is close to those measured for the bright inner jets of thePWN. We used the off-pulse interval to isolate pulsar emission and measure thecompact pulsar wind nebula (PWN) spectrum in hard X-rays. We also measured thespectrum from the south-western (SW) region of the PWN which is resolved byNuSTAR from the compact PWN. For both regions, we fit the NuSTAR spectra bythemselves and together with the Chandra X-ray Observatory spectra. We foundthat the compact PWN spectrum requires a more complex model than a simple PLwith evidence for exponential cutoff in 50-80 keV. We do not find such evidencefor the spectrum extracted from the SW PWN region, located farther from thepulsar, implying the energies over 600 TeV for the pulsar wind particles. Thismay indicate in-situ particle acceleration in that region.

NuSTAR observation of the Vela pulsar and its nebula