On the recent detection of new oscillations in rapidly oscillating Ap star HD 137949 - 1st result

We report the 39h of high-speed photometry of HD 137949 using the 0.5-m optical telescope of the South African Astronomical Observatory (SAAO). The Johnson-B photometric data were obtained between 2013 June 12 and July 11, in search of frequency solutions for the oscillations in HD 137949. Frequency analysis of our nightly data sets reveals that its known principal frequency of oscillation (ν=2.01478 mHz) is amplitude modulated on nightly basis. Frequency analysis of the entire data set also reveals that the known principal frequency of oscillation has slightly shifted from its earlier known value of ν=2.014781±0.000003 mHz to ν1=2.014834±0.000006 mHz; with a secured detection of new frequency at ν2=2.013001±0.000014 mHz. We discuss the possible implication of the presence of this new frequency (ν2) vis-a-vis finding an explanation for the new behaviour in the oscillation of HD 137949.