Abstract

We present a new asteroseismic analysis of KIC 6048106, a Kepler Algol-type eclipsing binary star in a circularized orbit with P-orb = 1.559361 +/- 0.000036 d. Based on a physical model for the binary and its corresponding set of fundamental parameters (T-eff= 7033 +/- 187 K, M-1 = 1.55 +/- 0.11 M-circle dot , R-1 = 1.58 +/- 0.12 R-circle dot and T-eff = 4522 +/- 103 K, M-2 = 0.33 +/- 0.07 M-circle dot , R-2 = 1.78 +/- 0.16 R-circle dot , respectively for the primary and the secondary component), we obtained the residual light curve after removal of the full binary model, including a 290-d activity cycle for the secondary component. In this work, we used the method of Fourier analysis of the residual light curve in combination with least squares optimization for the frequency analysis. We detected seven dominant, independent gravity (g) modes as well as 34 low-amplitude acoustic (p) modes. The g modes in the range of 1.96-2.85 d(-1 )have a mean spacing of Delta Pi(mean) = 1517.92 +/- 131.54 s. Though of much lower amplitude, additional significant frequencies were detected in the intervals 7.49-15.2 d (-1) and 19-22.5 d(-1) (i.e., in the p mode region), with corresponding dominant modes V maxi = 11.745 +/- 0.001 d(-1) and v., = 20.960 +/- 0.002 d(-1) . From its position in the HR diagram, we conclude that the primary component is the source of the detected hybrid pulsations. Consequently, the pulsation constants, Q, of the high frequencies cover the range of 0.028-0.064 d. Furthermore, v(43) (19.037 +/- 0.002 d(-1)) might correspond to the fundamental radial mode (Q = 0.033 +/- 0.007 d). The other frequencies in the range of 19-22.5 d (-1)could be radial or non-radial overtone modes. Moreover, the low-amplitude p modes show an equidistant splitting by f(orb) ,which we interpret as tidal splitting following theoretical predictions.