Overview of future interferometric GW detectors Giovanni Andrea Prodi, University of Trento and INFN, many credits to Michele Punturo, INFN Perugia New perspectives on Neutron Star Interiors Oct.9-13 2017, ECT*, Trento 1
Terrestrial Detectors Advanced detectors 2015-2025 GEO, Hannover, 600 m aligo Hanford, 4 km 2015 ~2024 ~2019 2017 AdV, Cascina, 3 km aligo Livingston, 4 km 2
Detectors sense GW amplitude The amplitude of the GW signal emitted by a mass distribution with quadrupolar moment Q l l h 2G 1 Q 4 c r 10 r r Considering an uniform distribution of GW sources, 10 times more detection range correspond to 10 3 increase of signal rate 3
plans for LIGO-Virgo surveys Performance upgrades by steps, interleaved by scientific observation runs: O1, O2, O3, design arxiv: 1304.0670v4 KAGRA & LIGO & VIRGO Design sensitivity: 1000x gain in surveyed volume of the Universe with respect to first generation detectors Binary BH detection rate: 50-500 /year Binary NS detection rate: 0.3-300 /year Aug. 26, 2017 G.A.Prodi, ICNFP-2017 4
Benefits of adding Virgo sky localization greatly improved e.g. GW170814: PRL 118, 221101 (2017) L1H1: 1200 deg 2 L1H1V1: 100 deg 2 L1H1V1: 60 deg 2 at 90% confidence directional sensitivities + triangulation the more the detectors, the better. comparable peformances for any 3- detector configurations performances vary on waveform morphology, Signal-to-Noise ratio, source direction in the network frame Aug. 26, 2017 G.A.Prodi, ICNFP-2017 5
global 2019+ scenario Light travel times [ms] Two more interferometers will join LIGO and Virgo: KAGRA (Japan, 2019) and LIGO India - IndIGO - (approved in 2016) sky coverage of the whole observatory almost omnidirectional Aug. 26, 2017 G.A.Prodi, ICNFP-2017 6
2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 AdV+ AdV AdV+ A+/Voyager aligo A+ A+ 1.7x gain in range Limited upgrades Squeezed light Improved mirror coating Heavier mirrors KAGRA LIGO India Voyager Voyager Additional 2x gain in range Major upgrade of instruments Cryogenic Silicon or Sapphire optics at 1550nm New mirror coatings Current infrastructures Installation Commissioning Data taking Other 7
from Berry Barish, 2017 Context of G3: Where will we be? 6-July-17 DAWN III G3 Workshop - Syracuse 8
from Berry Barish, 2017 Context of G3: Where will we be? Cryogenic Mirror KAGRA Kamioka Mine Underground Technologies crucial for next-generation detectors; KAGRA can be regarded as a 2.5-generation detector. G-1701270
What Next? Although Advanced GW detectors era just started and although GW have been just detected, the GW scientific community is investigating the long term future What class of 3G instruments? Einstein Telescope LIGO Cosmic Explorer Where? ET possible sites Why? Motivation for a next generation of GW interferometers When? Is it the right time to work on 3G? 10
The Einstein Telescope http://www.et-gw.eu/ 11
The ET design study Design study funded by the EC in FP7 (2008-2011) Involving France, Germany, Italy, the Netherlands, UK Now the ET community includes also Hungary, Poland and Spain Project included in sectorial roadmaps (GWIC, APPEC, OECD,. ) and worldwide recognized as leading 3G project 8th Einstein Telescope Symposium,BMarch 2017, Birmingham 12
The ET idea To realise a 3G GW observatory 3G: Factor 10 better than advanced (2G) detectors Observatory: Wide frequency, with special attention to low frequency (few HZ) Stellar mass Black Holes Capable to work alone (characteristic to be renegotiated) Localization capability High duty cycle: redundancy 50-years lifetime of the infrastructure Capable to host the upgrades of the hosted detectors 13
The ET infrastructure 14
ET Sensitivity Curve: xylophone AdV ET-D 15
Technologies The main ingredients are: Size: 10km vs 3km Xylophone design: ET-LF, ET-HF ET-Low Frequency: Underground Cryogenics Silicon (Sapphire) test masses Large test masses New coatings New laser wavelength Seismic suspensions Frequency dependent squeezing ET-High Frequency: High power laser Large test masses New coatings Thermal compensation Frequency dependent squeezing 16
LIGO Cosmic Explorer see first 3G instrument design targets CQG 34, 044001 (2017) new infrastructure to host also upgrades of 3G instruments on-surface vs underground under discussion 17
from Berry Barish, 2017 G3: Some Big Issues Science Motivations and Goals GWIC Committee (must be done in the context of projected G2) Science Goals Technical Performance Frequency vs Sensitivity Goals? Network Performance Goals (e.g. Pointing Accuracy)? Strategic Issues How many G3 Detectors are required? G3 Detectors: Identical or Different? How Internationally Organized/Funded/Implemented? Present GW Model: Collaboration of Collaborations? Globally Organized, like ILC, SKA? Global w/ Strong Host, like CERN LHC, DUNE? Limited Partnerships, like ALMA, LSST, TMT? 6-July-17 DAWN III G3 Workshop - Syracuse 18
Where ET? 19
ET site(s) In the Design Study several EU sites have been investigated 20
Underground Seismic noise Measurement Underground sites are the candidates for a very quiet site Credits: J.v.d. Brand 21
Underground Seismic noise Measurement Underground sites are the candidates for a very quiet site Credits: J.v.d. Brand 22
Day/Night variability vs population density Credits: J.v.d. Brand 23
Day/Night variability vs population density Credits: J.v.d. Brand 24
Why 3G detectors? 25
Beyond the detection The GW detection is a crucial milestone, but, what kind of physics is possible to do with improved / 3G GW detectors? The Physics of Extreme in: Fundamental physics Gravity Astronomy & Astrophysics Cosmology 26
Extreme matter Neutron Stars (NS) are a laboratory of nuclear physics at densities unreachable in Lab We don t know the state of matter in NS, we need measurements 27
NS Equation of State There is a plethora of possible NS EOS 28
Observing BNS mergers constraining the EOS: Tidal deformability l of the NS under external field is related to its EOS and it affects the binary orbital evolution Post merger remnant emission Crucial: high SNR 29
Disentangle EOS (on Advanced) Agathos+, 2015 30
From Salvatore Vitale, LIGO DAWN III, 2017 For BHs normal modes depend only on mass and spin Meauring at least 2 normal modes allow to check this relation: a smoking gun for BH vs alternatives 31
Extreme Gravity: do we need the darkness? Today we need more matter in the Universe to keep GR G1 R Rg Dark 8 ' T T 4 8 G G G 4 4 T c 2 To verify GR in condition of strong field could test the need of modified gravity theories c c But the Einstein field equations are the simplest solution in a curved spacetime There are a series of alternative theories of the gravity (for example f(r) theories) that could introduce an extra-curvature stressenergy tensor 32
Credit:B.Sathyaprakash Extreme Universe: GRB progenitors Short GRB are probably emitted by BNS In a multi-messenger context, if GRB are observed simultaneously with GW, it is possible to solve the GRB enigma 33
Extreme Universe: GRB progenitors Short GRB are probably emitted by BNS In a multi-messenger context, if GRB are observed simultaneously with GW, it is possible to fit the cosmological model of the Universe GW GRB are localised at high z. Crucial: high rate = huge detection distance To reconstruct Dark Energy parameters with relevant precision it is needed to observe 100 s of BNS coalescences associated with GRB in one year B.S.Sathyaprakas et al, CQG 27 (2010) 2015006 W M : total mass density W L : Dark energy density H 0 : Hubble parameter w: Dark energy equation of state parameter 34
When 35
1985 Virgo AdV aligo ET 1990 White Paper, CDR (1989) 1995 2000 2005 15 years Approval (1994) Final Design, TDR (1995) Beginning Infrastructure (1996) Completion installation Detector (2003) First AdV sensitivity projection (2004) Scientific data taking (2007) AdV White Paper, CDR (2005) Approval (2009) CDR (1999) Funding (2006) Building (2008) First Idea (2005) 2010 2015 Decommissioning (2011) First orders (2010) TDR (2012) Completion Installation (2016) First data taking (2017) Installing completion (2014) Data taking (2015) CDR (2011) 2020 TDR? 2025 Construction? 36
1985 Virgo AdV aligo ET 1990 1995 2000 2005 2010 2015 2020 White Paper, CDR (1989) Approval (1994) Final Design, TDR (1995) Beginning Infrastructure (1996) Completion installation Detector (2003) First AdV sensitivity projection (2004) Scientific data taking (2007) 15 years Decommissioning (2011) AdV White Paper, CDR (2005) Approval (2009) First orders (2010) TDR (2012) Completion Installation (2016) First data taking (2017) CDR (1999) Funding (2006) Building (2008) Installing completion (2014) Data taking (2015) First Idea (2005) CDR (2011) TDR? 2025 Construction? 37
1985 Virgo AdV aligo ET 1990 1995 2000 2005 2010 2015 2020 White Paper, CDR (1989) Approval (1994) Final Design, TDR (1995) Beginning Infrastructure (1996) CDR (1999) Completion installation Detector (2003) First AdV sensitivity projection (2004) AdV White Paper, CDR (2005) Scientific data taking Funding (2006) (2007) Approval (2009) Building (2008) Decommissioning (2011) First orders (2010) TDR (2012) 15 years Completion Installation (2016) First data taking (2017) Installing completion (2014) Data taking (2015) First Idea (2005) CDR (2011) TDR? 2025 Construction? 38
1985 Virgo AdV aligo ET 1990 1995 2000 2005 2010 2015 2020 2025 White Paper, CDR (1989) Approval (1994) Final Design, TDR (1995) Beginning Infrastructure (1996) Completion installation Detector (2003) First AdV sensitivity projection (2004) Scientific data taking (2007) Decommissioning (2011) AdV White Paper, CDR (2005) Approval (2009) First orders (2010) TDR (2012) Completion Installation (2016) First data taking (2017) CDR (1999) Funding (2006) Building (2008) Installing completion (2014) Data taking (2015) 15 years First Idea (2005) CDR (2011) TDR? Construction? 39
2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 AdV+ AdV AdV+ A+/Voyager aligo A+ Voyager KAGRA LIGO India Mission definition Space system development elisa ESFRI Roadmap ET ET Infrastructure Technical Design ET Detector Technical Design ET Observatory & Detector funding ET site construction - detector installation & commissioning Cosmic Explorer CE site&detector installation Installation Commissioning Data taking Other 40