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Einstein Telescope! in 1916 Einstein Predicted Gravitational Waves As a Consequence of His Theory of General Relativity

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Einstein Telescope! in 1916 Einstein Predicted Gravitational Waves As a Consequence of His Theory of General Relativity The Einstein-Telescope Listening to the murmurs of the Universe (Status and Prospects) Harald Lück AEI Hannover Max-Planck Institute for Gravitational physics Leibniz Universität Hannover, 17.3.2021 Institute for Gravitational physics Content • Gravitational waves • What are we talking about? • What have we detected so far? • What do we intend to measure? aLIGO + KAGRA • GW Detectors • How do they work? • What have we got? aLIGO+ INDIA AdV+ • How to improve? aLIGO + 3G south • Einstein Telescope! In 1916 Einstein predicted Gravitational Waves as a consequence of his Theory of General Relativity The problem is: ∆퐿 2 퐺 푑2푄 1 ℎ = = 퐿 푐4 푑푡2 푑 with Gravitational waves are ripples 2퐺 = ퟏퟎ−ퟒퟒ푠2푘−1푚−1 in space and time caused by changing 푐4 gravitational fields How big is DL caused by a Gravitational wave? Effect of a gravitational wave on a length of 4km h = h10= -22 Gravitational waves C.Carreau propagate – at the speed of light : ESA and cause Credit measurable changes in the distance between objects “Plus” polarization “Cross” polarization The Gravitational Wave Spectrum Cosmic Strings BH and NS Binaries Supernovae Relic radiation Extreme Mass Ratio Inspirals Supermassive BH Binaries Binaries coalescences Spinning NS 10-16 Hz 10-9 Hz 10-4 Hz 100 Hz 103 Hz Inflation Probe Pulsar timing Space detectors Ground based Source Giles Hammond: Adapted from M. Evans (LIGO G1300662-v4); adapted by H. Lück Working principle of a GW Detector: Michelson Interferometer Credit: MIT/Caltech LIGO Laboratory Lots of external disturbances Power lines Molecule Humans crossing Laser beam Seismic disturbance Wind/Weather Thermal Bath Quantum Back-Action noise Magnetic fields Planes Lightning The advanced GW Network Advanced LIGO Hanford, GEO600, 2011 2015 Advanced LIGO INDIA, 2024 Advanced Virgo 2016 KAGRA 2018 Advanced LIGO Livingston, 2015 Sensitivity improvement LIGO <-> aLIGO 11 “Observation of THE Detection Gravitational Waves from a GW150914 Binary Black Hole Merger” 14. September Detection of a 2015 transient signal in 09:50:45 UTC both advanced LIGO = 11:50:45 CEST detectors • Breakthrough Prize fundamental Physics 3M$ • Shaw Prize in Astronomy 1.2 M$ Preise • Gruber Cosmology Prize 0.5 M$ • Kalvi Prize 1 M$ • OSA team engineering award • Niedersächsische Staatspreis 25 k€ • Wissenschaftspreis Behrens Stiftung 30k€ • Körber Preis 0.75 M€ • Otto Hahn Preis 50 k€Nobel Preis 2017 ! Presidents Medal of Royal Society of Edinburgh LVK Observation runs Median O3a: LHO: 108MPc (1.64xO2) LLO: 135 MPc (1.53xO2) Virgo: 45 MPc (1.73XO2) GW150914 https://arxiv.org/pdf/2010.14527.pdf GW170817: A Binary Neutron star merger Electromagnetic follow-up Led to largest astronomical observation campaign Localisation by Trilateration Virgo, Cascina, Italy LIGO, Livingston, LA LIGO, Hanford, WA Slide: Stefan Hild (modified) LVK Observation runs Median O3a: LHO: 108MPc (1.64xO2) LLO: 135 MPc (1.53xO2) Virgo: 45 MPc (1.73XO2) GW150914 https://arxiv.org/pdf/2010.14527.pdf O4 („not before June 2022“) O3aO3a O3bO3b Observing plans and public alerts: https://www.ligo.org/scientists/GWEMalerts.php https://dcc.ligo.org/LIGO-G2001862/public Gravitationswellendetektionen Coalescing binaries observed so far O1 – O3a 150M⊙ plot/index.html - NS? BH? LIGO-P2000061-v14 https://ligo.northwestern.edu/media/mass Source: Detection Highlights from O3a GW190425 - 2nd neutron star merger Astrophys. J. Lett. 892, L3 (2020) • Only measured by two detectors (LLO and Virgo) • Poorer localisation compared to GW170817 1.61-2.52 M⊙ • No EM counterpart found 1.12-1.68 M⊙ • Unexpectedly heavy pair: total mass of 3.4+0.3 -0.1 M⊙ is 5σ from galactic mean Image: T. Dietrich (Nikhef), S. Ossokine, A. Buonanno (MPI for Gravitational Physics), W. Tichy (Florida Atlantic University) and the CoRe-collaboration 22 Slide from David Wu, AEI GW190412 & GW190814 – the “odd couples” Phys. Rev. D 102, 043015 (2020) Astrophys. J. Lett. 896, L44 (2020) • First detections of a large GW190412 mass imbalance, mass 24.4 – 34.7 M⊙ ratio (q ~ 0.28 and 0.11) 7.4 – 10.1 M • First evidence of higher ⊙ order GW modes. Dominant Higher quadrupole order • Additional info from multipoles higher order modes GW190814 allowed better parameter 22.2 – 24.3 M constraints ⊙ • GW190814: what was the smaller object? 2.50 – 2.67 M⊙ Images: N. Fischer et al. Max Planck Institute for Gravitational Physics, Simulating eXtreme Spacetimes project 23 Slide from David Wu, AEI GW190521 – the “big fish” [1] Phys. Rev. Lett. 125, 101102 (2020) [2] • Most massive system observed: objects (1) 85 and 66 M⊙ • Remnant intermediate mass black hole - first direct observation of IMBH • One or both components in the pair instability mass gap (50 - 120 M⊙) Image: LIGO/Caltech/MIT/R. Hurt (IPAC) 24 Slide from David Wu, AEI, modified Sensitivities of the 2nd Generation aLIGO ET Advanced LIGO GEO600, 2011 Voyager CE Hanford, 2015 Advanced LIGO INDIA, 2024 Advanced Virgo KAGRA 2018 2016 Advanced LIGO Livingston, 2015 Infrastructure will reach an end of lifetime and a limit in performance (self noise, size) → New infrastructures Design Pläne 2008 – 2011 Increase size 4km → 10 km Advanced LIGO ET 4 km 10 km Cosmic Explorer will have 40 km arms → gain a factor 10 w.r.t. advanced LIGO 3 Detektoren in Dreiecksanordnung rel. Längenänderung : DL/L = 2% Noise Budget (aLIGO example) Noise Sources: ▪ High Frequencies ShotHigh laser Noisepower/squeezing ▪ Mid Frequencies ShotSqueezing noise, rad. press. Noise EURegio Thermal noise of Coatings Meuse-Rhine Better coatings/ cryogenic operation ▪ Low frequencies Rad.Low Laser press. Power noise SeismicBetter suspensions ThermalLonger suspensions suspension noise Newtonian noise ControlNew control noisesignals LIGO-T1800044-v3 Sensitivities of the 2nd Generation aLIGO ET Current aLIGO Advanced LIGO GEO600, 2011 Voyager CE Hanford, 2015 Advanced LIGO INDIA, 2024 Advanced Virgo KAGRA 2018 2016 10x Advanced LIGO Livingston, 2015 10x Infrastructure will reach an end of lifetime and a limit in performance (self noise, size) → New infrastructures Challenge: Low Frequency improvement factor Newtonian Noise ▪ The Virgo suspension is almost good enough for filtering the seismic disturbances and keeping the mirrors quiet enough A longer suspension is needed to improve filtering at low frequencies Newtonian Noise circumvents this isolation chain → Go underground SEISMIC WAVE Credit M.Lorenzini ET - Xylophone Concept ET - LF ET – HF 300 K low-power, cryogenic high-power, room-temperature ET-HF: low-frequency detector high-frequency detector • High power laser • High circulating light power • Thermal compensation • Large test masses • New coatings • Frequency dependent squeezing ET-LF: 10 – 20 K • Cryogenics • Seismic suspensions • Silicon (Sapphire) test masses • Large test masses • New coatings • New laser wavelength • Frequency dependent squeezing, Filter cavities ET Xylophone Sensitivity ET - HF ET - LF ET-LF ET-HF ET Total ET – LF Subdividing the ET - HF task Detector Subsystems ETMy Cryo Cold Cooler Vacuum link Chain Ly tank ITMy Mirror suspension chain LASER sideview L displayed only x for one mirror PR ITMx ETMx for clarity SR Control Faraday IMC Faraday Isolator Filter Cavity Colours for subsystems: Isolator Core optics, coatings Light sources Plot(data) Squeezer Quantum Enhancements Auxiliary optics Computer OMC Sensing Sensing and Control PD Seismic Isolation & Suspensions Cryogenics Cosmic Explorer (USA) Oberirdisch Empfindlichkeit 10x advanced Det. 2 Phasen Sensitivities in the 3G era aLIGO+ KAGRA aLIGO+ INDIA AdV+ aLIGO + 3G south/ NEMO Reaching for the „whole universe“… Horizon distance CBC Sources throughout the universe Credit: E. Hall (MIT) Slide layout: Sheila Rowan, modified 3G Gravitational Wave Science Sub-slides credit: B. Sathyaprakash, Dawn III Workshop, https://wiki.ligo.org/LSC/LIGOworkshop2017/WebHome Einstein Telescope Where are we? ESFRI Roadmap Proposal submitted by: • Italy (Lead Country) • Netherlands • Belgium • Spain • Poland 40 Slide: Michele Punturo 2020 ET ESFRI Proposal: the consortium level • The ET ESFRI consortium is composed by the institutions signing the ET consortium agreement (CA) • Very light CA at this level • 41 Institutions signed the ET consortium • The ET consortium is coordinated by INFN and Nikhef (Stan Bentvelsen, Antonio Zoccoli) From LKV Sept2020, modified https://www.google.com/maps/d/edit?mid=1ljTBCqTyCmVncbYaeUVcpQA3udceyg2b&usp=sharing 41 Slide: Michele Punturo ESFRI Phases: 3G Enabling technologies development idea Design Sites qualification Preparatory Costs evaluation Implementation Building the ET collaboration ET Operation CDR Building ET consortium Raising Construction Raising initial funds funds Site Decisi ET RI construction ESFRI proposal ESFRI on decision Opera ET detectors -tion construction RI operative TDR Pre-engineering studies ET Installation Detector Operative TDR 2004 2010 2008 2018 2019 2020 2021 2022 2023 2024 2025 2026 2030 2032 2028 42 ET Governance Scheme (proposal) ET Boards ESFRI Proposal: • The Instrument Science Board (ISB) • deliver the ET Technical Design Report (ET-TDR) for infrastructure and detectors • identify the missing technologies and suggest a (living) plan for R&D activities. first version ca. March 2021. • The Observational Science Board (OSB) • will detail the ET science case • will prepare the data analysis requirements • will indicate the computing requirements for ET • The Site Preparation Board (SPB) • will coordinate the effort on the site related activities • formulate the site specifications for Einstein Telescope
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