Suzaku Detection of Diffuse Hard X-Ray Emission outside Vela X
- Authors: Katsuda, S; Mori, K; Petre, R; Yamaguchi, H; Tsunemi, H; Bocchino, F; Bamba, A; Miceli, M; Hewitt, J; Temim, T; Uchida, H; Yoshii, R
- Publication year: 2011
- Type: Articolo in rivista (Articolo in rivista)
- Key words: ISM: individual (Vela Pulsar Wind Nebula), ISM: supernova remnants, X-rays: ISM
- OA Link: http://hdl.handle.net/10447/65113
Abstract
Vela X is a large, 3ı 2ı, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we have found hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index was measured to be constant at Γ 2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations of relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.