Since their discovery as VHE emitters by H.E.S.S. in 2004, the high-energy peaked BL Lacs PKS 2005-489 and H 2356-309 have been monitored at VHE to study their flux and spectral variability. To sample their SED, several multiwavelength campaigns with X-ray satellites have been performed, showing important spectral changes. Here we present the results of 3 years of H.E.S.S. observations together with multiwavelength data, in the context of the SED evolution and in comparison with the historical states.

HESS Collaboration

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 3 (OG part 2), pages 945-948