THE EMISSION-LINE KNOT IN THE SEYFERT 2 GALAXY NGC 5347

We report on narrow-band H alpha imaging and long-slit spectroscopy at intermediate resolution from [Ne v] lambda 3425 Angstrom to [S III] l ambda 9532 Angstrom at PA=25.degrees 5 through the nucleus of the Seyf ert 2 galaxy NGC 5347. The nucleus shows very-high-excitation lines, s uch as [Ne v], He Ir, [Fe VII] and [Fe x]. At 3 arcsec to the north-ea st there is a high-excitation emission knot which also shows the Ca II infrared triplet in absorption, with an equivalent width of 8.2 Angst rom, indicating the presence of red supergiant stars. We find, however , that the spectrum of this knot has emission-line intensities charact eristic of photoionization by a hard AGN-like continuum. This continuu m emission seems to be emitted anisotropically by the nucleus. Evidenc e for the anisotropic radiation field comes from photon deficit argume nts, whereby the flux of ionizing photons emitted by the nucleus in th e direction of the knot and in the line of sight to the Earth is calcu lated, The knot is located perpendicular to the stellar bar, and just inside the inner Lindblad resonance.