HESS J0632 + 057 is a gamma-ray binary composed of a compact object orbiting a Be star with a period of about 315 days .
Extensive X-ray and TeV gamma-ray observations have revealed a peculiar light curve containing two peaks , separated by a dip .
We present the results of simultaneous observations in hard X-rays with NuSTAR and in TeV gamma-rays with VERITAS , performed in November and December 2017 .
These observations correspond to the orbital phases \phi \approx 0.22 and 0.3 , where the fluxes are rising towards the first light-curve peak .
A significant variation of the spectral index from 1.77 \pm 0.05 to 1.56 \pm 0.05 is observed in the X-ray data .
The multi-wavelength spectral energy distributions ( SED ) derived from the observations are interpreted in terms of a leptonic model , in which the compact object is assumed to be a pulsar and non-thermal radiation is emitted by high-energy electrons accelerated at the shock formed by the collision between the stellar and pulsar wind .
The results of the SED fitting show that our data can be consistently described within this scenario , and allow us to estimate the magnetization of the pulsar wind at the location of the shock formation .
The constraints on the pulsar-wind magnetization provided by our results are shown to be consistent with those obtained from other systems .