2002MNRAS.331..284T

The centre of NGC4151 has been observed in the J band with the SMIRFS integral field unit (IFU) on the UK Infrared Telescope. A map of [Feii] emission is derived, and compared with the distributions of the optical narrow-line region and radio jet. We conclude that, because the [Feii] emission is associated more closely with the visible narrow-line region than with the radio jet, it arises mainly through photoionization of gas by collimated X-rays from the Seyfert nucleus. The velocity field and strength with respect to Paβ are found to be consistent with this argument. The performance of the IFU is considered briefly, and techniques for observation and data analysis are discussed.