A young stellar group associated with HD 199143 (d=48 pc)

We present new optical and ultraviolet spectroscopy of the anomalous EUV em itter HD 199143 (F8V). High resolution spectra in the Her and NaID waveleng th regions show evidence for very rapid (a few hundred km s(-1)) rotation o f the stellar photosphere. Using archive IRAS data we also show that the st ar has excess emission above photospheric levels at 12 mum. IUE data of HD 199143 reveal the presence of emission lines of Mg II, C I, C Ir, C III, C IV, Si IV, He II and N V and show a large variability, both in the continuu m and line fluxes. We propose that all available data of HD 199143 can be e xplained by assuming that is has been spun up by accretion of material from a close T Tauri like companion, responsible for the emission lines, the ul traviolet variability and the excess infrared emission. The bursting or fla ring nature of this object, mostly in high energies, could be explained as episodic mass transfer between the star and its close companion. We show th at HD 199143 and the Li-rich late-type dwarf BD-17 degrees 6128 form a phys ical pair and suggest that both may be part of a new nearby (48 pc) young ( similar to 10(7) yr) stellar association in Capricornius.