* Astronomy

Title: Discovery of hybrid gamma Dor and delta Sct pulsations in BD+18 4914 through MOST spacebased photometry
Authors: J.F. Rowe, J.M. Matthews, C. Cameron, D.A. Bohlender, H. King, R. Kuschnig, D.B. Guenther, A.F.J. Moffat, S.M. Rucinski, D. Sasselov, G.A.H. Walker, W.W. Weiss

We present a total of 57 days of contiguous, high-cadence photometry (14 days in 2004 and 43 in 2005) of the star BD+18 4914 obtained with the MOST satellite. We detect 16 frequencies down to a signal-to-noise of 3.6 (amplitude \~ 0.5 mmag). Six of these are less than 3 cycles/day, and the other ten are between 7 and 16 cycles/day. We interpret the low frequencies as g-mode gamma Doradus-type pulsations and the others as delta Scuti-type p-modes, making BD+18 4914 one of the few known hybrid pulsators of its class. If the g-mode pulsations are high-overtone non-radial modes with identical low degree l, we can assign a unique mode classification of n={12, 20, 21, 22, 31, 38} based on the frequency ratio method.

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