Complex Velocity Fields in the Shell of T Pyxidis

Abstract

We present spatially-resolved, moderate-resolution spectrophotometry of the recurrent nova T Pyx and a portion of the surrounding shell. The spectrum extracted from a strip of width 10'' centered on the star shows well-known, strong emission lines typical of old novae, plus a prominent, unfamiliar emission line at 6590 Angstroms. This line, and a weaker companion at 6540 Angstroms which we also detect, have been previously reported by Shahbaz et al., and attributed to Doppler-shifted H alpha emission from a collimated jet emerging from T Pyx. We demonstrate that these lines are instead due to [NII] 6548, 6584 from a complex velocity field in the surrounding nebula. The comments of past workers concerning the great strength of HeII 4686 in T Pyx itself are also reiterated.