Seeing-limited radial velocity field mapping of extended emission line sources using a new imaging Fabry–Perot system

Abstract

<scp>TAURUS,</scp> a new Fabry–Perot imaging device, designed to obtain complete seeing–limited radial velocity field maps of extended emission-line sources, is described. A servo-controlled Fabry–Perot is used with a focal reducer and a two-dimensional photon-counting (area detector) system, to obtain the velocity information. The system has been fully tested and the first observations of the highly complex velocity field of the irregular galaxy, M82, are used to illustrate the power of the instrument.