ASCA observations of deep ROSAT fields - III. The discovery of an obscured Type 2 AGN at z=0.67

We report on the discovery of a narrow-emission-line object at z = 0.672 detected in a deep ASCA survey. The object, AXJ0341.4-4453, has a flux in the 2-10 keV band of 1.1 +/- 0.27 x 10(-13) erg s(-1) cm(-2), corresponding to a luminosity of 1.8 x 10(44) erg s(-1) (q(0) = 0.5, H-0 = 50 km s(-1) Mpc(-1)). It is also marginally detected in the ROSAT 0.5-2 keV band with a flux 5.8 x 10(-15) erg s(-1) cm(-2). Both the ASCA data alone and the combined ROSAT/ASCA data show a very hard X-ray spectrum, consistent with either a flat power law (alpha < 0.1) or photoelectric absorption with a column of n(H) > 4 x 10(22) cm(-2) (alpha = 1). The optical spectrum shows the high-ionization, narrow emission lines typical of a Seyfert 2 galaxy. We suggest that this object may be typical of the hard sources required to explain the remainder of the X-ray background at hard energies.