2009ApJ...699L.153Z

We study nonthermal photon emission properties from Vela X in both a leptonic and a hadronic-leptonic model. In the leptonic model, it is difficult to reproduce the observed photon spectrum from X-ray to TeV bands using reasonable model parameters; the model results can compare with either the observed data at the TeV band (the total energy of electrons required to match the observations is W_e~ 6.1x10⁴⁵ erg) or those at the X-ray band (W_e~ 1.3x10⁴⁵ erg). In the hadronic-leptonic model, however, the observed photon spectrum can be reproduced in the hadronic-leptonic model and TeV photons are mainly from π⁰ decay in proton-proton interaction. The energy required for iron nuclei released in the pulsar wind is W_Fe ~ 2.1x10⁴⁸ erg and the energy of iron nuclei transferred to positrons is W_e+ ~ 8.4x10⁴⁵ erg in this case.