Abstract We present the evolution of optical spectra and lightcurves of the fast nova V1674 Herculis during 150 days past its eruption. Using the post-eruption AAVSO light curve, we have calculated the orbital period of V1674 Her to be 0.153 days. There is no unambiguous white dwarf spin period in our data. The optical spectra show that the ionisation increases with time. A morpho-kinematic analysis of the Hα line profile indicates a bipolar morphology with polar blobs and an equatorial ring. Lyman beta fluorescence is found to be the dominant mechanism for the excitation of neutral oxygen. On day 19.87, Ne III this spectrum is accretion-dominated.
Rawat et al. (Sat,) studied this question.