Warm absorbers around the nucleus of the active galaxy UGC 11763

M.V. CARDACI, M. SANTOS-LLEÓ, Y. KRONGOLD, G.F. HÄGELE, A.I. DÍAZ, P. RODRÍGUEZ-PASCUAL

ESA, Villafranca del Castillo, Madrid, Spain

Workshop; Inter-Departmental Science Workshop; 2009

European Space Astronomy Centre (ESAC), European Space Agency (ESA)

We present a detailed analysis of all data taken by the XMM-Newton satellite of UGC11763 to characterize the different components that are emitting and absorbing radiation in the vicinity of the active nucleus. The continuum emission was studied through the EPIC spectra taking profit of the spectral range of these cameras. The high resolution RGS spectra were analyzed in order to characterize the absorbing features and the emission line features that arise in the spectra of this source. A power law with a photon index Gamma = 1.72(+0.03,−0.01) accounts for the continuum emission of this source in the hard X-rays from 10 down to 1 keV. At lower energies, a black body model with kT = 0.100±0.003 keV provides a good description of the observed soft excess. The absorption signatures in the spectra of UGC11763 are consistent with the presence of a two phase ionized material (log U = 1.65[+0.07,−0.08]; 2.60 ± 0.009 and log N_H = 21.2 ± 0.2; 21.51 ± 0.01 cm−2, respectively) in the line of sight. The physical conditions found are consistent with the two phases being in pressure equilibrium. The low ionization component is more ionized than typically found for warm absorbers in other Seyfert 1 galaxies. There are also signatures of some emission lines: OVII He(r), OVII He(f), a blend of the NeIX He triplet and FeXVIII at lambda 17.5 Å.