A search for pulsations in four late-type giants

I observed four late-type giant stars to search for oscillations similar to those observed on Arcturus. For these observations, I used the Kitt Peak National Observatory Coude Feed telescope and Fiber Optic Echelle spectrograph. I observed alpha Ari, gamma Per, epsilon Tau, and alpha Aur (a close binary composed of two G giants) for 12 nights, observing each star similar to 5 times per night in order to detect oscillations with periods on the order of 2 days. I chose these stars, which range in spectral types from G8 III to K2 III, because of their spectral similarity to Arcturus (alpha Boo, K1 III), for which earlier observations revealed oscillations. No oscillations were detected on any of the four stars observed in this campaign. The upper limits of the oscillation amplitudes at periods comparable to those seen on Arcturus fall well below those observed for Arcturus. Continued observations of Arcturus are required to determine whether the observed period and amplitude are stable, or if the structure of Arcturus is different from the late-type giants observed in this campaign.