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[vsnet-obs 6446] V723 Cas

Dear Dr. T. Kato
This text will be published in an IAU circular.

T. Iijima and L. Rosino, Asiago Astrophysical Observatory.

                       Nova Cas 1995  (V723 Cas)
A spectrum of Nova Cas 1995 (V723 Cas) covering the range from 460 to 710 
nm with a resolution 0.06 nm was taken at Asiago Observatory on 1997 July 
1.09 U.T. using an Echelle spectrograph mounted on the 182 cm reflector. In 
the spectrum prominent emission lines of [Fe VII] at 572.1 nm (eq.w.=-2.76 
nm) and at 608.6 nm (eq.w.=-7.04 nm) were detected. These lines were not 
seen in a spectrum taken on 1997 May 30.1 U.T. with the same instruments. 
The intensity of the emission line He II 468.6 nm relative to H-beta 
increased from 0.16 to 0.54 during the same period, while [O III] 500.7 nm 
was nearly stable and its intensity was about 0.15 of H-beta in both 
spectra. Prominent emission lines in the last spectrum by the order of 
decreasing intensity are: H-alpha, H-beta, He II 468.6, He I 587.6, He I 
706.5, [N II] 575.5, [Fe VII] 608.6, [O III] 500.7, He I 667.8, [Fe VII] 
572.1, Si II 504.1, He II 541.2, [Fe VI] 517.7, [Fe II] 464.0, [Fe III] 
527.0, He I 501.6, [S III] 631.0, [Ca V] 530.9, [Fe II] 497.3, [O III] 
495.5, Si II 505.6, Si II 637.1, [Fe VII] 515.8, etc. About two years after 
the explosion this slowest classical nova seems to have entered in the 
nebular stage. The high intensities of Si II lines, however, are fairly 
unusual for spectra of classical novae in this stage.