Further optical observations of the recurrent nova U Scorpius

ATel #15499; L. N. Kondratyeva , E. K. Denissyuk, I. V. Reva, S. A. Shomshekova, G. K. Aimanova (Fesenkov Astrophysical Institute, Almaty, Kazakhstan)
on 5 Jul 2022; 08:50 UT
Credential Certification: Ludmila Kondratyeva (lu_kondr@mail.ru)

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A new outburst of the recurrent nova U Scorpius has been registered by Masayuki Moriyama on 2022 June 6.720 UT. We have obtained low resolution spectra (range 4300-5400 and 6300-7400 Ang at 1.1 Ang/pix dispersion) of U Scorpius on June 9.840, 11,81, 25,72 and 26.68 UT (on days 3.07-20 after optical maximum) The 70-cm telescope AZT-8, the slit spectrograph and CCD SBIG 3200 were used for observations. Spectrophotometric standard HD 170296 was used for the flux calibration. The spectra exhibit emission lines of the HI, He I, N II, and N III. There are no absorption components on our spectrograms. The spectrum of U Scorpius showed the rapid variations as the nova faded. Radiation fluxes in the lines decreased and their ratio changed. Thus, the Hbeta line dominated in the first spectrum, but two days later the 4660 line became the strongest among the lines. In addition, a significant weakening of the HeI, 4471 line was registered. Table 1 presents observed fluxes (in units of 10^(-12) erg/cm^2/s) and FWHM (km/sec)

 
Dates of  observations (UT)    2022 June 09.84  June 11.81   June 25.72   June 26.68 
Epoch after maximum (in days)	  3.07	          5.10	       19.0	    20.0 
4340, Hgamma	Fabs		                  8.9+/-0.2		 
	        FWHM		                  5740+/-200		 
4471, HeI. 	Fabs	         10.7+/-1.5	  1.3+/-0.2		 
	        FWHM	         5840+/-150	  2200+/-150		 
4660, NIII	Fabs	         28.6+/-2.5	  19.9+/-2.2		 
	        FWHM	         6890+/-200	  6900+/-200		 
4861,Hbeta	Fabs	         46.7+/-2.5	  19.1+/-2.5		 
	        FWHM	         6660+/-250	  6550+/-250		 
5000,HeI,NII	Fabs	         18.7+/-1.1	  10.8+/-1.5		 
	        FWHM	         5820+/-200	  5750+/-200		 
6562, Halpha	Fabs			                       0.56+/-0.05  0.56+/-0.05 
	FWHM			                               1830+/-100   1820+/-100 

Photometry of U Scorpius was carried out with the 1-meter telescope of Carl Zeiss Jena and a sample of B V Rc filters.

 
Dates 2022 UT	JD-2400000	    B	            V	             R 
June. 14.68	59745.170	12.36+/-0.03	12.66+/-0.02	12.67+/-0.06 
June. 16.70	59747.198	13.05+/-0.03	13.16+/-0.02	13.33+/-0.06 
June. 28.67	59757.178	14.41+/-0.03	14.20+/-0.03	14.36+/-0.02