## Response of a star to gravitational waves
^{1} Institute for Advanced Studies in Basic Sciences, P.O.
Box 45195-159, Zanjan, Iran
(iasbsgz1@rose.ipm.ac.ir, sobouti@rose.ipm.ac.ir)^{2} Department of physics, Shiraz University, Shiraz,
Iran^{3} Center for Theoretical Physics and Mathematics, AEOI,
Tehran, Iran
We investigate the possibility of the excitation of the oscillation modes of polytropic stars by gravitational waves. We decompose the displacement vector field of a normal mode into its irrotational and solenoidal components and show that the interaction with the gravitational waves takes place through the irrotational component. We calculate the absorption cross section of the waves for different modes and find that the cross section for modes are orders of magnitudes larger than the modes. In the sequence the cross section is largest for the fundamental mode and decreases with increasing mode order.
## Contents- 1. Introduction
- 2. Normal modes of a star
- 3. The Hilbert space of the displacement field
- 4. The
*g*and*p*components of the displacement field - 5. Interaction with gravitational waves
- 5.1. Energy absorption
- 5.2. Absorption cross section
- 6. The overlap integrals
- 7. Concluding remarks
- Acknowledgements
- References
© European Southern Observatory (ESO) 1997 Online publication: June 30, 1998 |