Reflection Component in the Hard X-Ray Emission from the Seyfert 2 Galaxy Mrk 1210

The Seyfert 2 galaxy Mrk 1210 was found to exhibit a flat hard X-raycomponent by ASCA, although ASCA could not distinguish whether it is anabsorbed direct component or a reflected one. We then observed Mrk 1210 withBeppoSAX, and found that the X-ray spectral properties are quite different fromthose of ASCA, as have been confirmed with XMM-Newton; the flux issignificantly higher than that in the ASCA observation, and a clear absorptioncut-off appears below 5 keV. A bright hard X-ray emission is detected up to 100keV. The reflection component is necessary to describe the BeppoSAX PDSspectrum, and represents the ASCA hard component very well. Therefore, the hardcomponent in the ASCA spectrum is a reflected one, whose intensity is almostconstant over 6 years. This indicates that a dramatic spectral variability isattributed to a large change of the absorption column density by a factor of>5, rather than the variability of the nuclear emission. The change in theabsorption-column density means that the torus is not homogeneous, but has ablobby structure with a typical blob size of < 0.001Comment: 9 pages, 5 figures, accepted for Pablications for the Astronomical Society of Japa