ANISOTROPIC EMISSION, STELLAR POPULATION AND X-RAY SOURCES IN THE SEYFERT-2 GALAXY ESO-138-G01

We present narrow-band CCD images of the high-excitation Seyfert 2 gal axy ESO138-G01, centred on the emission lines [O III] lambda 5007, H a lpha + [N II] lambda lambda 6548, 6584 and adjacent continua. The cont inuum-subtracted [O nr] image presents an elongated jet-like structure to the west of the nucleus which is only weakly visible in the Ha ima ge, and which we conclude is ionized by the nuclear source. The ioniza tion map shows high excitation at the nucleus and at the 'jet'. The co ntinuum ratio map shows that this galaxy is very blue for its morpholo gical type, consistent with the large contribution of a young stellar population up to 3 kpc from the nucleus. We also propose that ESO 138- G01 is the hard X-ray source previously identified with the nearby gal axy NGC 6621.