γ-ray and optical light curves of V1723 Sco (top) and V6598 Sgr (bottom) calculated from the Fermi-LAT data (black and gray) and taken from the AAVSO database in the V-band (green) and unfiltered (orange) respectively. Flux estimates with 1σ statistical uncertainties only are plotted when TS and N_pred > 4 and 95% upper limits otherwise. The blue windows indicate the time periods of the NuSTAR observations. t_disc corresponds to the optical discovery of both novae (Table 1).