We present in this paper the hard X-ray view of the pulsar wind nebula in G11.2-0.3 and its central pulsar PSR J1811-1925 as seen by NuSTAR .
We complement the data with Chandra for a more complete picture and confirm the existence of a hard , power-law component in the shell with photon index \Gamma = 2.1 \pm 0.1 , which we attribute to synchrotron emission .
Our imaging observations of the shell show a slightly smaller radius at higher energies , consistent with Chandra results , and we find shrinkage as a function of increased energy along the jet direction , indicating that the electron outflow in the PWN may be simpler than that seen in other young PWNe .
Combining NuSTAR with INTEGRAL , we find that the pulsar spectrum can be fit by a power-law with \Gamma = 1.32 \pm 0.07 up to 300 keV without evidence of curvature .