Michele Punturo ET scientific Coordinator INFN Perugia and EGO On behalf of the ET design study team 1ET-Michele Punturo

E.M. Astronomy visibleInfrared 408MHz WMAP X-ray  -ray GRB Current e.m. telescopes are mapping almost the entire Universe Keywords: Map it in all the accessible wavelengths See as far as possible Galaxy UDFy in Ultra Deep Field image (Hubble Telescope)  13.1 Gly 2ET-Michele Punturo M. Trenti, Nature 467, 924–925 (21 October 2010)

GW Astronomy ? visibleInfrared 408MHz WMAP X-ray  -ray GRB Enlarge as much as possible the frequency range of GW detectors Pulsar Timing Arrays Hz Space based detectors (LISA, DECIGO) Hz Ground based detectors Hz Improve as much as possible the sensitivity to increase the detection volume (rate) and the observation SNR 3ET-Michele Punturo GW ?

Detection distance (a.u.) GW interferometer past evolution Evolution of the GW detectors (Virgo example): 2003 Infrastructu re realization and detector assembling 2008 Same infrastructure Proof of the working principle Commissioning & first runs 4 ET-Michele Punturo year Upper Limit physics

GW interferometer present evolution Evolution of the GW detectors (Virgo example): 2003 Infrastructu re realization and detector assembling 2008 Same infrastructure Proof of the working principle Upper Limit physics 2011 enhanced detectors Same infrastructure Test of “advanced” techs UL physics 2017 Same infrastructure Advanced detectors First detection Initial astrophysics Commissioning & first runs 5 ET-Michele Punturo Detection distance (a.u.) year

Advanced detectors 6 ET-Michele Punturo Advanced detectors are, for example, promising: An increase of the BNS detection distance up to 200 MPc 10 8 ly Enhanced LIGO/Virgo+Virgo/LIGO Credit: R.Powell, B.Berger Adv. Virgo/Adv. LIGO Universe in 1 Gly arXiv: v2arXiv: v2 [astro-ph.HE]

3 rd generation? Evolution of the GW detectors (Virgo example): 2003 Infrastructu re realization and detector assembling 2008 Same infrastructure Proof of the working principle Upper Limit physics 2011 enhanced detectors Same infrastructure Test of “advanced” techs UL physics 2017 Same infrastructure Advanced detectors First detection Initial astrophysics 2022 Same Infrastructure (  20 years old for Virgo, even more for LIGO & GEO600) Commissioning & first runs Precision Astrophysics Cosmology 7 ET-Michele Punturo Detection distance (a.u.) year Limit of the current infrastructures

Beyond Advanced Detectors GW detection is expected to occur in the advanced detectors. The 3 rd generation should focus on observational aspects: Astrophysics: Measure in great detail the physical parameters of the stellar bodies composing the binary systems NS-NS, NS-BH, BH-BH Constrain the Equation of State of NS through the measurement of the merging phase of BNS of the NS stellar modes of the gravitational continuous wave emitted by a pulsar NS Contribute to solve the GRB enigma Relativity Compare the numerical relativity model describing the coalescence of intermediate mass black holes Test General Relativity against other gravitation theories Cosmology Measure few cosmological parameters using the GW signal from BNS emitting also an e.m. signal (like GRB) Probe the first instant of the universe and its evolution through the measurement of the GW stochastic background Astro-particle: Contribute to the measure the neutrino mass Constrain the graviton mass measurement 8 ET-Michele Punturo

Target Sensitivity Target sensitivity of a new, 3 rd generation “observatory” (the Einstein Telescope, ET) is the result of the trade off between several requirements ET-Michele Punturo9 1.Science targets 2.Available technologies (detector realization) 3.Infrastructure & site costs 1.Infrastructure & site costs 2.Available technologies (detector realization) 3.Science targets As starting point of our studies we defined two rough requirements: Improvement by a factor 10 the advanced sensitivities Access, as much as possible, to the 1-10Hz frequency range Let see few of the new possibilities open by such as observatory

Gamma Ray Bursts Recent satellite missions shown a series of explosive events in the Universe generating a huge quantity of energy : GRB ET-Michele Punturo10 The origin of GRB is still unknown but some model has been developed

BNS & GRB ET-Michele Punturo11 Simultaneous detection of GW from BNS and GRB by a specialized detector will allow: to solve the GRB enigma Understand the Universe geometry (Cosmology) To measure the contribution of dark matter and dark energy to the Universe model

Supernova Explosions Mechanism of the core-collapse SNe still unclear Shock Revival mechanism(s) after the core bounce TBC ET-Michele Punturo12 GWs generated by a SNe should bring information from the inner massive part of the process and can constrains on the core-collapse mechanisms

The Einstein Telescope The Einstein Telescope project is currently in its conceptual design study phase, supported by the European Community FP7 from May 2008 to July ET-Michele Punturo 13 Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK INFN (Istituto Nazionale di Fisica Nucleare) has a leading role in the definition of the seismic filtering design (WP2), cryogenics requirements (WP1-WP2) and seismic noise requirements (WP1)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK MPG (Max-Planck-Institut für Gravitationsphysik) has a leading role in the definition of the QND technologies for the optical design (WP3) and an effective management support (WP5)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK CNRS (Centre National de la Recherche Scientifique) has a leading role in the definition of the optics for ET (WP3) and contributes to the ET science case definition (WP4)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK UNIBHAM (University of Birmingham) has a leading role in the definition of the optical design of ET (WP3) and contributes to the ET science case definition (WP4)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK UNIGLASGOW (University of Glasgow) has a leading role in the definition of the overall sensitivity ET (WP3), to the suspension requirements (WP2) and to the science case definition (WP4)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK VU (Nikhef) has a leading role in the definition of ET site requirements and specifications (WP1) and contributes to the science case definition (WP4)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK CU (Cardiff University) has a leading role in the definition of ET science case (WP4)

ET beneficiaries The ET beneficiaries are the core institutes of the GEO600 and Virgo collaborations MTR-Brussels 14/12/ Participant Country EGO Italy France INFN Italy MPG Germany CNRS France University of Birmingham UK University of Glasgow UK Nikhef NL Cardiff University UK EGO (European Gravitational Observatory), thanks to its expertise in the management of the Virgo site it has the (centralized) management (WP5) responsibility of the overall project and it collaborates to the definition of the ET infrastructures (WP1)

Targets of the Design Study Evaluate the science reaches of ET Define the sensitivity and performance requirements Site requirements Infrastructures requirements Fundamental and (main) technical noise requirements Multiplicity requirements Draft the observatory specs Site candidates Main infrastructures characteristics Geometries Size, L-Shaped or triangular Topologies Michelson, Sagnac, … Technologies Evaluate the (rough) cost of the infrastructure and of the observatory ET-Michele Punturo22

How ET goes beyond the 2 nd generation? ET-Michele Punturo h(f) [1/sqrt(Hz)] Frequency [Hz] 1 Hz10 kHz Seismic Thermal Quantum Seismic Newtonian Susp. Thermal Quantum Mirror thermal 3 rd generation ideal target

The ET idea Advanced Virgo will implement already most the cutting edge technologies, but at the end it will be limited by the infrastructure Obviously the realization of ET will push for an intense technology developments in lasers, optics, mechanics, electronics,.. ET-Michele Punturo24 But, to go beyond the infrastructure limitation there are three possibilities: 1. Go in the space 2. Go on the Moon 3. Go underground !!! LISA, DECIGO Crazy (up to now) LCGT, ET

Seismology network In ET we started the investigation using the support and the data of the ORFEUS* Network (>200 sites in Europe) ET-Michele Punturo25 * Observatories and Research Facilities for European Seismology

ET-WP1: Site search Underground sites (mines, labs, …) Seismometer (Nikhef) ET-Michele Punturo26

WP1: Site search: Many sites visited in Europe ET-Michele Punturo27

Underground Seismic noise Measurement ET-Michele Punturo28

Day/Night variability vs population density ET-Michele Punturo29

The infrastructure Schematic view ET-Michele Punturo30 Full infrastructure realized Initial detector(s) implementation 1 detector (2 ITF) Physics already possible in coincidence with the improved advanced detectors Progressive implementation 2 detector (4 ITF) Redundancy and cross- correlation Full implementation 3 detector (6 ITF) Virtual interferometry 2 polarizations reconstruction

ET-Michele Punturo31 Credits Martin Doets

Complex infrastructure Xylophone design and triangular geometry ask for a complex hosting infrastructure ET-Michele Punturo32 The target of the ET project is, in fact, the realization in Europe of a fundamental Research Infrastructure that will host the Gravitational Wave observatory for decades, opening the GW precision astronomy and implementing the technical evolutions in the detectors composing the observatory The realization of the infrastructure should be triggered by the first detection, but the implementation of the full observatory will be diluted in the years (modularity!)

The ET project … an artistic view ET-Michele Punturo33

“Political” achievements ET had a series of “political” important achievements: Scientific initiative is back on this side of the Ocean The whole European GW community is coordinated by EGO in a joint initiative The theoretical and Astrophysics community has been involved in the ET design with reciprocal advantages ET science team is involving more than 220 scientists Some of them are not belonging to the 8 beneficiaries!! ET-Michele Punturo34

ET Timeline ET-Michele Punturo 35 ET Design ET Prep. phase ET needs to be in the ESFRI roadmap (2012 revision?) ET needs to fill the gap ET science team needs a coordination tool

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