Classical nova outburst of the dwarf nova V392 Persei

D. Chochol, AI SAS

The well-known dwarf nova V392 Per bursted as a classical 
nova on April 29, 2018 . Our UBVRCIC postoutburst photometry 
 allowed to estimate absolute magnitude of the nova at maximum 
MVmax = - 9.3±0.57 mag, adopting relations for classical novae 
from Gaia data, as well as to determine the colour excess 
E(B-V) = 0.9±0.1  and distance to the nova d = 3.55±0.6 kpc. 
The optical spectrum obtained in brightness maximum resembles 
that of the F2 supergiant. Its bolometric luminosity computed 
by fitting the continuum by atmospheric and black-body models 
is in agreement with the luminosity found from photometry. 
The CN Per 2018 can be classified as a fast super-Eddington nova 
with an outburst LC of plateau type. Our spectroscopy suggests 
 He/N spectrum classification, large expansion velocities, and 
triple-peaked emission-line profiles during the decline, explained 
by equatorial ring seen nearly face on and a bipolar flow aligned 
almost with the line of sight. The post maximum spectra of CN Per 2018 
and available radio data were used to estimate the inclination angle 
of the system as 9 degrees. The difference in intensity of redward 
and blueward emission bumps is possible to explain by about 1.5 times 
higher density of the receding outtflow. The rapid increase of the 
bipolar outflow radial velocities by   ̴ 300 km/s around the day 5 
after maximum was caused by the fast polar winds from the burning 
white dwarf after shrinking of its pseudophotosphere.