HIGH-ENERGY PARTICLES IN THE WIND NEBULA.OF PULSAR B1509-58 AS SEEN BY INTEGRAL

摘要

We present observations with the INTEGRAL IBIS telescope of the wind nebula powered by the young pulsar B1509—58, and we discuss the spatial and spectral properties of the unpulsed emission in the 20-200 keV energy band. The source extension and orientation along the northwest-southeast axis correspond to the jet emission seen at keV and TeV energies. The hard X-ray spectrum is consistent with the earlier BeppoSAX measurements. It follows a power law with a photon index α = -2.12 ± 0.05 up to 160 keV. A possible break at this energy is found at the 2.9 σ confidence level. The 0.1-100 keV data are consistent with synchrotron aging of pairs in the jet and yield a magnetic field strength of 22-33 μG for a bulk velocity of 0.3c-0.5c. The synchrotron cutoff energy thus corresponds to a maximum electron energy of 400-730 TeV.