Brief Summary of "Advanced Gravitational Wave Detectors"

1. Brief Summary of"Advanced Gravitational Wave Detectors" Tao Yi

3. Contents An introduction to gravitational wave astronomy and detectors Current laser interferometer detectors - three case studies Technology for advanced gravitational wave detectors Technology for third generation gravitational wave detectors

4. LIGO

5. Outline • General introduction of gravitational waves • Einstein equation • Luminosity • Field force & energy flux • Wave function • Sources of gravitational waves

6. Einstein equation an enormous number of order 1043 leading to the weak coupling of gravitational waves to matter （k below） General Introduction of gravitational waves T: the stress energy tensor G: the Einstein curvature tensor c: the speed of light G: Newton's gravitational constant

7. General Introduction of gravitational waves The Luminosity of gravitational waves （BH）

8. z z x x y y General Introduction of gravitational waves Gravitational wave field force lines: (a) '+' polarisation; (b)'×' polarisation

9. General Introduction of gravitational waves Any source can be characterised by an amplitude h and flux F detected at the Earth or by luminosity LG This value represents a considerable energy flux, 3% of the solar intensity on Earth, although such high flux densities can only sustained in short bursts. Hence, the energy of a gravitational wave is extremely high for a very small amplitude.

10. (W.F.A) General Introduction of gravitational waves transverse-traceless gauge

11. General Introduction of gravitational waves

12. The output from a single gravitational wave detector consists of a time series F+,× are the dimensionless detector antenna pattern functions for the two polarisation. n(t) is the detector noise. General Introduction of gravitational waves

13. Sources of gravitational waves Supernovae Neutron star coalescence Rates of coalescing compact binaries Gravitational wave standard sirens Gravitational waves and gamma-ray bursts Continuous gravitational wave sources Low-frequency sources Stochastic background from the era of early star formation Cosmological gravitational waves from the Big Bang

14. Sources of gravitational waves Low-frequency sources Theoretically, the wave forms for the coalescence of BHs are identical at high or low frequency - only the masses must increease. The real case for astrophysics is different. We are interested in BHs of 105--109 solar masses, since there is an opportunity to obscure extreme mass ratio binaries, where a low-mass object behaves more like a test mass as it samples and traces the extreme curvature of a massive black hole. The frequency set by high-mass BH, the amplitude set by the low-mass object.

15. Sources of gravitational waves • Many hypotheses • Many mechanisms Cosmological gravitational waves from the Big Bang

16. Bonus Some information about the detectors • The LIGO are being rebuilt to create the first advanced detectors • The Virgo will shut down for its upgrade • The GEO 600 will continue to listen to the universe

17. Thanks for listening!