Poster abstract details

It has been established earlier that sharp features like the
base of the convective zone or the second helium ionisation zone inside
a star give rise to sinusoidal oscillations in the frequencies of
pulsation. The acoustic depth of such features can be estimated from
this oscillatory signal in the frequencies. We apply this technique for
the CoRoT frequencies of the solar-type star HD49933. This is the first
time that such analysis has been done of seismic data for any star other
than the Sun. We are able to determine the acoustic depth of the base
of the convective zone of HD49933 within 10% error from the second
differences of the frequencies. The acoustic depth of the HeII
ionisation zone can also be determined, but with a larger error. The
locations of these layers using this technique is in agreement with the
current seismic models of HD49933.