Oskar Möller & Tobias Berstler
During the Lab Course “Photometry “ the star with the rather incompact name “ASASSN-V J061111.16+395420.2 “ was observed. This δ-Scuti star is variable and therefore changes its magnitude periodically. Unlike the more widely known δ-Cepheids this class of stars usually has a much shorter period and is therefore easier to measure in a single night.
After the uncooperative weather over Spain ceased to interfere with our plans, the observation took place during the night from 15th to 16th December 2023. Besides the visible underlying (surprisingly symmetric) sine wave, an additional mode of oscillation or a disturbance was visible.
Fitting one Fourier series with a periodicity P wasn’t enough to describe the complexity of the oscillation in an acceptable way. So a Fourier series with an additional periodicity P2 was fitted to the light curve. This yields two periodicities P1 = (0.0935 ± 0.0002) d and P2 = (0.505 ± 0.007) d. The first periodicity differs from the theoretical value by only 0.32%. Since the second periodicity is longer than the observation time, this result has to be taken with a grain of salt. Several observations over several nights could clarify the result and quantify the second period more precisely.
Both plots show the measured data with different overlayed functions: on the left the final combination of the two Fourier series, on the right both Fourier series for P1 (orange) and P2 (red) are plotted separately.
In addition to the planned observation target, three other variable stars could be identified in the recorded part of the sky. In particular a rather faint variable star was found, which could be identified as the eclipsing binary star system ZTF J061158.93+395851.8. Observing this star with adjusted telescope settings could yield interesting results.