Measuring the Universe with Einstein s Gravita3onal Waves Prof. Dr. Karsten Danzmann Albert Einstein Ins-tute (AEI) Max Planck Society and Leibniz Universität Hannover
What are Gravita3onal Waves? Distor3on of space and 3me, propaga3ng at the speed of light 2
The Length Change is Small! Supernova in nearby galaxy Squeezing space by 10-21 1 km baseline changes by 1/1000 of a Proton diameter (10-18 m = 1 AXometer)! For a few milliseconds! 3
Original Interferometer of Michelson and Morley 1887 Sensi'vity 1887: Δl= 600 pm =0, 000 000 000 6 m Laser interferometer today: 0, 000 000 000 000 000 000 1 m/ Hz 4
Gravita3onal Wave Sources Ground- based detectors observe in the audio band The analogue of op3cal astronomy Audio band 1 Hz 10 khz
World- Wide Laser Interferometric Gravita3onal Wave Detector Network LIGO GEO600 (future) LCGT LIGO Virgo 80m / 5 km Source: A. Lazzarini, modified 3 km
LIGO: Two Sites, Three Ifos One interferometer with 4 km Arms, one with 2 km Arms One interferometer with 4 km Arms
VIRGO: The French- Italian Project 3 km armlength near Pisa
GEO600 - German- Bri3sh collabora3on, loca3on Hannover / Germany - Michelson Interferometer with power and signal recycling U Birmingham U Mallorca 9 Glasgow
LIGO Hanford (USA) Largest Dedicated Computer Cluster in the World for GW GEO600 operated by AEI Data Analysis at AEI LIGO Livingston (USA) VIRGO (Pisa)
Crab Pulsar (1054 AD) The Astrophysical Journal, 713, p671 685, 2010: SEARCHES FOR GRAVITATIONAL WAVES FROM KNOWN PULSARS WITH SCIENCE RUN 5 LIGO DATA Mountains on Crab Pulsar are less than 2m high!
Present Sensi3vity (S5 ) 10 M sun - 10 M sun BH - BH binaries Event rates Based on popula3on synthesis [Kalogera s summary of literature] merger Ini3al IFO event rates Range: 100 Mpc 1 / 600yrs to ~3/yr 12
Future Plans : Advanced LIGO with Technology from GEO! Observable volume several thousand 3mes LIGO! Installa3on 2011-15 GEO contribu3ons: New suspensions New Op3cs 200 W lasers Signal Recycling Resonant Sideband Extrac3on
Advanced LIGO and AdVirgo 10 M sun - 10 M sun BH - BH binaries Event rates Based on popula3on synthesis [Kalogera s summary of literature] Ini3al IFO event rates Range: 100 Mpc 1 / 600yrs to ~3/yr Advanced IFO event rates Range: z = 0.45 1 / mo to ~30/day merger merger 14
Interferometer Quantum Noise Quantum Shot Noise Standard Quantum Limit (SQL)
Interferometer Quantum Noise [Unruh 1982] [Jaekel, Reynaud 1990] Shot Noise Optimised Squeezing of Laser Light (SQL)
Squeezed Light in Hannover
12.7 db World Record Squeezing r 0.5 r 1 r 1.5 T. Eberle et al., Phys. Rev. LeX. 104, 251102 (2010). 18
GEO600: The First Gravita3onal Wave Detector using Squeezed Light!
Virgo and GEO Science Run S6e June 3 Sept 5, 2011 Strain [1/sqrt(Hz)] Frequency [Hz] 20
Astrowatch for GEO600 un3l 2015 LIGO and Virgo offline for upgrading GEO600 taking data 24/7 Occasional interrup3ons for commissioning and upgrades 21
The Third Generation: The Einstein Gravitational Telescope E.T. Overall beam tube length ~ 30km Underground loca3on Cryogenic Squeezing LF and HF Ifos 22
Conceptual Design Study in European Union FP7 Program AEI Co- PI Kick- Off May 2008 Final Presenta3on May 20, 2011 in Cascina
Ar3s3c/Schema3c views hxp://www.et- gw.eu/e3mages ET event - May 2011 24
Corner and ancillary halls hxp://www.et- gw.eu/e3mages ET event - May 2011 25
Laser Interferometer Space Antenna 3 Satellites 5 Million km arms 50 Million km behind Earth Einstein 26
LISA: A Mature Concept Aver first studies in 1980s, M3 proposal for 4 S/C ESA/NASA collabora3ve mission in 1993 LISA selected as ESA Cornerstone in 1995 3 S/C NASA/ESA LISA appears in 1997 Baseline concept unchanged ever since!
LISA Pathfinder Tes3ng LISA Technology in Space! 28
LISA Pathfinder Take one LISA link Squeeze it into one spacecrav 29
Electrode Housing and Test Mass: LISA Design 30
Flight Model Units replace EMs
The Spacecrav Wai3ng for a launch in 2014! 32
But then in March 2011... 33
LISA Redefinition Study Redesign for ESA-only mission Cost-cap for ESA cost at 850 M plus member state contributions around 200 M Ø Build on LISA Pathfinder hardware Ø Shorter arms, smaller telescopes, simpler orbits, less mass Ø Can use cheaper launcher Still requires lots of work, but: à We can do it! à A history class science mission! Soyuz Fregat
elisa- NGO Layout 35
evolved LISA (elisa) Science Cosmology Expansion of universe and Dark Energy equa3on of state Black Holes Evolu3on, seismology and bothrodesy Precision tests of strong gravity No- hair theorem Galaxy mergers History and evolu3on Structure of galaxy Complete WD mapping and stellar evolu3on Helioseismology Solar g- modes Big Bang Primordial GW radia3on 36
elisa Science and Astronomy Cosmology Expansion of universe and Dark Energy equa3on of state Black Holes Evolu3on, seismology and bothrodesy Precision tests of strong gravity No- hair theorem Galaxy mergers History and evolu3on Structure of galaxy Complete WD mapping and stellar evolu3on Helioseismology Solar g- modes Big Bang Primordial GW radia3on 37
elisa: 100 Million WD Binaries! elisa will hear every binary system in the Galaxy that has a period < 2 hr About 3 000 resolvable in 2 yr <3 loca3on, 10 inclina3on, distances down to 1 % Of the 50 op3cally known ultra- compact binaries: à 8 are guaranteed calibra3on sources for elisa- NGO 38
elisa Science and Astronomy Cosmology Expansion of universe and Dark Energy equa3on of state Black Holes Evolu3on, seismology and bothrodesy Precision tests of strong gravity No- hair theorem Galaxy mergers History and evolu3on Structure of galaxy Complete WD mapping and stellar evolu3on Helioseismology Solar g- modes Big Bang Primordial GW radia3on 39
Binary Black Holes at large Redshiv! Contours of SNR, equal mass merger (optimal) Redshiftà Massà 40
Trace Galaxy Evolu3on through Black Hole Mergers Hierarchical structure forma3on: many galaxy mergers Most galaxies have BH in center: à Many BH mergers Strong elisa sources
elisa Black Hole Physics at high SNR BBH rest mass 10 4 10 7 Out to redshiv z 7 Redshived mass to 0.1%- 1% Absolute spin to 0.01-0.1 Luminosity distance 1 50 % Sky loca3on 3-10 42
LISA Technology for Gravity Field Missions AEI in close collaboration with IfE Hannover and ZARM in QUEST Cluster of Excellence
Gravity Recovery and Climate Experiment (GRACE) GRACE Mission (UTCSR, GFZ, DLR, JPL). Image credit: NASA GFZ Tiwari et al., Dwindling groundwater resources in northern India, from satellite gravity observa-ons, Geophys. Research LeX. 36, L18401 (2009). Groundwater loss in India Velicogna, Increasing rates of ice mass loss from the Greenland and Antarc-c ice sheets revealed by GRACE Geophys. Research LeX. 36, L19503 (2009). Ice mass loss in Greenland
GRACE Follow- On Mission Approved! USA/Germany, approved in Dec 2011, launch in 2016! Laser interferometer instrument from Germany First- ever intersatellite laser ranging instrument! AEI: Design lead / PI for interferometry!
www.dfg-science-tv.de Einstein 46
http://www.einsteinathome.org/ GEO-600 Hannover LIGO Hanford LIGO Livingston Current search point Current search coordinates Known pulsars Known supernovae remnants Einstein 47