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CONTEXT: The Nova V1405 Cas, which erupted on 18 March 2021, showed a pre-maximum phase of almost two months. After the main maximum, during several month the nova only weakened slightly and showed clear fluctuations in brightness. AIMS: The aim of this work is to investigate the relationship between brightness and half-width (FWHM) and equivalent width (EW) of the H-alpha emission line, and from this to infer possible causes for the abnormal behavior of the Nova. METHODS: Magnitudes and spectra from online databases were used, the H-alpha line of the spectra was measured and 2-day normal values were formed in order to establish a temporal comparison. RESULTS: After the main maximum, during the period investigated by JD 2459292 to 2459305 at intervals of 2-5 weeks secondary maxima with different characteristics. The maxima of the equivalent width were 6-14 days after the respective brightness maxima. The maxima are interpreted as subsequent outbreaks of the nova. Possibly these are subsequent weaker eruptions of the nova or other mechanisms that lead to an increase in density in the envelope.

AR Herculis is an RR Lyrae star of type RRab whose spectral type ranges from A7 to F3. Its visual brightness varies between 10.59 mag and 11.63 mag (V). By analysis of 34,000 measurements from the AAVSO International Database and additional data from the BAV, 116 times of maximum between 2003 and 2015 were derived. For the time span 2009 to 2015, a new period value of P = 0.46999746(145) days was derived from the (O-C) analysis. Furthermore, the derived maximum timings indicate a strong Blazhko effect with a Blazhko period of PB = 32.062(13) days. The evolution of the observed maximum brightness Vmax, which decreased from 2009 to 2015 by 22 mmag/year, is also indicative of a Blazhko effect with PB = 29.528(17) d. The present work investigates the processes in the frequently used (O-C) vs. Vmax diagram by running several simulations based on assumed and observational data., Comment: 9 pages, 13 figures