T. Zwitter, Department of Physics, University of Ljubljana; and U. Munari, Padova and Asiago Astronomical Observatories, write: "High-resolution spectra (range 430-875 nm) of the recurrent nova U Sco (cf. IAUC 7113) were obtained on Feb. 27.2, 28.2, Mar. 1.2, and 2.2 UT with the Asiago 1.82-m telescope (+ CCD echelle spectrograph). The spectra are remarkably similar over the four nights. Only subtle profile changes are seen in N II, N III, C III, C IV, and He I emission lines. On the other hand, Balmer lines changed appreciably from saddle-like to single-peaked profiles. The FWZI of H-alpha has remained constant at 8900 km/s. Narrow emission components have not yet appeared."
International Astronomical Union Circular
- Pub Date:
- March 1999