1 / 80

Gravitational Wave Detectors: Resonator and Interferometer

This lecture explains the basics of gravitational wave detectors, focusing on the resonator and interferometer types. It covers the fundamental noise of interferometers and provides an introduction to the field of gravitational wave detection.

burksm
Download Presentation

Gravitational Wave Detectors: Resonator and Interferometer

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Detectors Kazuhiro Yamamoto Insitute for Cosmic Ray Research, The University of Tokyo KAGRA Summer School Lectures 30 July 2014 @University of Toyama, Toyama, Japan

  2. References (English book) P.R. Saulson, “Fundamentals of Interferometric Gravitational Wave Detectors” World Scientific Pub Co Inc (1994) M. Maggiore, “Gravitational Waves: Volume 1 : Theory and Experiments”, Oxford University Press (2007) Edited by D.G. Blair, E.J. Howell, L. Ju, C. Zhao, “Advanced Gravitational Wave Detectors” Cambridge University Press (2012)

  3. Reference (Japanese book) 中村　卓史、三尾　典克、大橋　正健　編 “重力波をとらえる ---存在の証明から検出へ” 京都大学出版会 (1998).

  4. Reference (Review paper) R. X. Adhikari, “Gravitational radiation detection with laser interferometry” Review of Modern Physics 86 (2014) 121-151.

  5. 0.Abstract I would like to explain … (1) Resonator as oldest type of detector (2) Interferometer as commonest type detector (3) Fundamental noise of interferometer

  6. Contents 1. Introduction 2. Resonator 3. Interferometer 4. Fundamental noise of interferometer 5. Summary

  7. 1.Introduction What is the gravitational wave ? 1915 A. Einstein : General theory of Relativity “Gravitation is curvature of space-time.” 1916 A. Einstein : Prediction of gravitational wave “Gravitational wave is ripple of space-time.” A. Einstein, S. B. Preuss. Akad. Wiss. (1916) 688. Wikipedia (A. Einstein, English)

  8. 1.Introduction Gravitational wave Speed is the same as that of light. Transverse wave and two polarizations http://spacefiles.blogspot.com

  9. 1.Introduction Interaction of gravitational wave is too weak ! Artificial generation is impossible ! Noexperiment which corresponds to Hertz experiment for electromagnetic wave Astronomical events Strain [(Change of length)/(Length)] : h ~ 10-21 (Hydrogen atom)/(Distance between Sun and Earth) No direct detection until now

  10. 1.Introduction There are a lot of kinds of detectors ! Resonant detector Interferometer (on Earth) Interferometer (Space) Doppler tracking Pulsar timing Polarization of cosmic microwave background and so on … Frequency range : 10-18 Hz – 108 Hz

  11. 2.Resonator Resonant detector Gravitational wave excites resonant motion of elastic body. Weber bar (commonest one) “300 years of gravitation” (1987) Cambridge University Press Fig. 9.8 Diameter : several tens cm Length : a few meters Resonant frequency : about 1 kHz

  12. 2.Resonator Joseph Weber (1919-2000) Pioneer of gravitational wave detection He is one of persons who proposed the concept of laser. Other persons (C.H. Townes, N.G. Basov, A.M. Prokhorov) won Nobel prize in Physics (1964). He started development of resonant detector. J. Weber, Physical Review 117 (1960) 306.

  13. 2.Resonator Weber event J. Weber, Physical Review Letters 22 (1969) 1302. “Evidence for discovery of gravitational radiation” Coincidence between two detectors (Distance is 1000 km) Direction of sources : Center of our galaxy

  14. 2.Resonator However, … Theorists pointed out that our galaxy disappears in short period if center of galaxy emits so large energy. No experimentalists could confirm Weber event even if they used detectors with better sensitivity ! We do not know what caused Weber event, but gravitational wave did not.

  15. 2.Resonator List of resonators First generation (room temperature) University of Maryland (U.S.A.) … Second generation (4 K) Explorer (Italy, CERN), Allegro (U.S.A.), Niobe (Australia), Crab (Japan) … Third generation (< 100 mK) Nautilus (Italy), Auriga (Italy), Mini-Grail (Netherlands), Mario Schenberg (Brazil) … This is not a perfect list !

  16. 2.Resonator List of resonators First generation (room temperature) University of Maryland (U.S.A.) … Second generation (4 K) Explorer (Italy, CERN), Allegro (U.S.A.), Niobe (Australia), Crab (Japan) … Third generation (< 100 mK) Nautilus (Italy), Auriga (Italy), Mini-Grail (Netherlands), Mario Schenberg (Brazil) …

  17. Exploler G. Pizzella, ET first general meeting (2008)

  18. NAUTILUS INFN - LNF G. Pizzella, ET first general meeting (2008)

  19. 2.Resonator AURIGA Padova G. Pizzella, ET first general meeting (2008)

  20. 2.Resonator About 3 kHz Mini-Grail Mario Schenberg O.D. Aguiar et al., Classical and Quantum Gravity 25 (2008) 114042. http://www.minigrail.nl/

  21. 2.Resonator Old but original resonators in Japan (Not bar and sphere) One of examples : Torsion detector (60 Hz) “Gravitational wave detection” Kyoto University Press (1998) Fig. 5-6. (Japanese) Best upper limit of continuous gravitational wave from Crab pulsar h<2*10-22 (Until 2008) T. Suzuki, “Gravitational Wave Experiments” World Scientific p115 (1995). S. Kimura et al., Physics Letters A 81 (1981) 302.

  22. 3.Interferometer Interferometer (on Earth) Gravitational wave changes length difference of two arms. Frequency : 10 Hz – 10 kHz

  23. 3.Interferometer Brief early history of interferometer “300 years of gravitation”(1987) Cambridge University Press Idea or suggestion F.A.E. Pirani (1956), Gertsenshtein and Pustovoit (1962), J. Weber (mid-1960’s) First interferometric detector G.E. Moss, L.R. Miller, R.L. Forward, Applied Optics 10 (1971) 2495. Detailed design and feasibility study R. Weiss (1972) https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=38618

  24. 3.Interferometer Longer baseline is better. However, budget is larger ! At most, baseline is on the order of km … km km How can we enhance effective baseline length ?

  25. 3.Interferometer Effective baseline length enhancement R.W.P. Drever, in Lecture Notes in Physics (Springer-Verlag, Berlin), Vol 124, p 321-338 (1983). R.W.P. Drever, in The Detection of Gravitational Waves (Cambridge University Press), p 306 (1991). D.R. Herriott, H.J. Schulte, Applied Optics 4 (1965) 883. D.Shoemaker et al., Physical Review D 38 (1988) 423.

  26. 3.Interferometer Effective baseline length enhancement All current interferometers have Fabry-Perot cavities. Issues of Delay-line : Larger mirror, Scattered light Issues of Fabry-Perot (control of mirror) was solved by Drever himself (Pound-Drever-Hall method for Fabry Perot cavity control, Applied Physics B 31(1983)97) and followers.

  27. 3.Interferometer Trivia Pound-Drever-Hall method, Applied Physics B 31(1983)97. Web site of Nobel foundation

  28. 3.Interferometer Ronald W.P. Drever Rainer Weiss Wikipedia (English) They shared Einstein Prize (2007, American Physical Society) “For fundamental contributions to the development of gravitational wave detectors based on optical interferometry, leading to the successful operation of the Laser Interferometer Gravitational Wave Observatory.” http://www.aps.org/programs/honors/prizes/einstein.cfm

  29. 3.Interferometer Power recycling (reduction of shot noise) Power recycling mirror R.W.P. Drever et al., in Quantum Optics, Experimental Gravity, and Measurement Theory, (Plenum, New York, 1983), p. 503. 29

  30. 3.Interferometer Signal Recycling and Resonant Sideband Extraction (change of interferometer response to gravitational wave) Signal recycling mirror B. J. Meers, Physical Review D 38 (1988) 2317. J. Mizuno et al., Physics Letters A 175 (1993) 273. 30

  31. 3.Interferometer List of interferometers First generation (past) LIGO (U.S.A.), VIRGO (Italy and France), GEO (Germany and U.K.), TAMA (Japan), CLIO (Japan) Second generation (present or near future, first detection) Advanced LIGO (U.S.A.), Advanced VIRGO (Italy and France), GEO-HF(Germany and U.K.), KAGRA (Japan) Third generation Einstein Telescope (Europe), LIGO III(U.S.A.)

  32. 3.Interferometer Sensitivity of km scale interferometer This graph is old one. 1st generation 10 times 2nd generation 10 times 3rd generation

  33. First and second generation interferometers LIGO (4 km) GEO (600 m) GEO-HF TAMA (300 m) Advanced LIGO KAGRA (3 km) CLIO (100 m) LIGO (4 km) Virgo (3 km) Advanced Virgo Advanced LIGO 33 33 33 33 33

  34. 3.Interferometer First generation : LIGO (U.S.A.) 4 km, Hanford and Livingston (3000 km distance) (U.S.A.) S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001.

  35. 3.Interferometer First generation : VIRGO (Italy and France) 3 km, Pisa (Italy) S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001.

  36. 3.Interferometer First generation : GEO (Germany and U.K.) 600 m, Hannover (Germany) S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001.

  37. 3.Interferometer First generation : TAMA (Japan) 300 m, Tokyo (Japan) S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001.

  38. 3.Interferometer First generation : CLIO (Japan) 100 m, Kamioka (Japan) S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001.

  39. 3.Interferometer Second generation Observation (km scale) : Soon ! We can expect first detection ! Advanced LIGO, Advanced VIRGO Upgrade of LIGO and VIRGO GEO-HF(Germany and U.K.), Upgrade of GEO (Now GEO-HF is only one interferometer in operation) KAGRA (Japan) Cryogenic technique Underground site (small seismic motion)

  40. Location of KAGRA 3 km, Kamioka (Japan) KAGRA is planed to be built underground at Kamioka, where the prototype CLIO detector is placed. By K. Kuroda (2009 May Fujihara seminar)

  41. 3.Interferometer CLIO (Japan) Prototype for KAGRA (cryogenic technique, same underground site) S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001. 41

  42. 3.Interferometer Third generation Einstein Telescope (Europe) 30 km vacuum tube in total Cryogenic technique Underground site (small seismic motion) LIGO Scientific Collaboration study : LIGO III (U.S.A.)

  43. 3.Interferometer Schedule M. Punturo et al., Classical and Quantum Gravity 27 (2010) 084007.

  44. 4.Fundamental noise of interferometer Interferometric gravitational wave detector Mirrors must be free and are suspended. S. Kawamura, Classical and Quantum Gravity 27 (2010) 084001. 44

  45. 4.Fundamental noise of interferometer Typical example of sensitivity of 2nd generation interferometer (KAGRA old one) http://spacefiles.blogspot.com

  46. 4.Fundamental noise of interferometer Seismic noise Vibration of ground shakes mirrors.

  47. 4.Fundamental noise of interferometer Thermal noise Mirrors and suspension are in heat bath. Random energy flow from heat bath Limit from statistical mechanics

  48. 4.Fundamental noise of interferometer Quantum noise Quantum amplitude and phase fluctuations of light Limit from quantum mechanics 48

  49. 4.Fundamental noise of interferometer Seismic noise Vibration of ground shakes mirrors. How can we reduce seismic noise ? (1) Small seismic motion site (2) Good vibration isolation system

  50. 4.Fundamental noise of interferometer Seismic noise (1) Small seismic motion site Where is silent sites ? Underground ! Kamioka mine M. Punturo, GWDAW Rome 2010 BFO (Black Forest Observatory): -162m BRG (Berggieshübel seism Observatory): -36m GRFO (Graefenberg borehole station): -116m Kamioka (Kamioka mine): -1000m

More Related