Towards Advanced Virgo Plus Raffaele Flaminio on behalf

+ Towards Advanced Virgo Plus Raffaele Flaminio on behalf the Virgo collaboration • • Introduction Content of Phase I Preparation for Phase II Summary March 15 th, 2019 1

+ Introduction March 15 th, 2019 2

+ Ad. V+: what? l Upgrade of Advanced Virgo l Goal in units of BNS range u From 100’s Mpc to more than 200’s Mpc (up to 300 Mpc) l Two phases project l Phase I u Moderate upgrade (no test masses change) l Phase II u More invasive upgrade (larger test masses) March 15 th, 2019 3

+ l Ad. V+: how? Phase I u Signal recycling (not done in Ad. V yet) u Higher laser power (Ad. V run with 20 W so far) u Frequency dependent squeezing (frequency independent squeezing already done in Ad. V) u Newtonian noise cancellation l Phase II u High power laser (200 W) u Larger beams » ~10 cm on end test masses, TBD on input masses u 100 Kg test masses » End test masses, TBC on input test masses u Better coatings: lower mechanical losses, less point defects, better uniformity » Depending on R&D results at the end of Phase I March 15 th, 2019 4

+ l Ad. V+: when? Phase I implemented between O 3 and O 4 u We need to know the downtime (depends on LIGO-Virgo-KAGRA joint plan) l Phase II implemented between O 4 and O 5 Phase I March 15 th, 2019 Phase II 5

+ l Ad. V+: how good? Potential sensitivities March 15 th, 2019 6

+ l Ad. V+: how good? Phase I: “hitting thermal noise wall” March 15 th, 2019 7

+ l Ad. V+: how good? Phase II: “pushing thermal noise wall” March 15 th, 2019 8

+ l l Ad. V+: how much? Budget (only Phase I shown): 11. 4 M€ Phase II estimation: 25 M€ March 15 th, 2019 9

+ l Ad. V+: who? The Virgo Collaboration (with contribution from AEI) 8 European countries: Italy, France, The Netherlands, Spain, Germany, Belgium, Hungary, Poland March 15 th, 2019 10

Ad. V+: management? + Virgo Steering Committee EGO consortium Project Supervisor Board Convener: G. Gemme EGO director Virgo Spokesperson Project Leader Technical Manager Quality responsible Commissioning coordinator Operations coordinator 3 Country representatives Ad. V+ Management Team Project Leader: R. Flaminio Technical Manager: H. Heitmann ITF: M. Was, SUM: H. Vocca, ESC: B. Swinkels, ENV: TBD, QNR: J. P. Zendri OSD J. Degallaix MIR L. Pinard ISC M. Mantovani NNC TBD SGD M. De Laurentis PSL N. Christensen TCS V. Fafone SRC N. Leroy INF A. Paoli SVS F. Sorrentino INJ A. Chiummo PAY E. Majorana DAQ A. Masserot VAC A. Pasqualetti SIN R. Bonnand SLC A. Chiummo SAT R. Passaquieti CAL L. Rolland EMS R. De Rosa FLT M. Tacca DET R. Gouaty VCRD G. Cagnoli SBE 15 th, March A. Bertolini 2019 11

+ More details on Phase I March 15 th, 2019 12

+ l Signal Recycling Signal recycling payload installed for Ad. V (telescope lens) u Lens to be replaced with mirror u Mirror: substrate available, coating to be done l Ring Heater to be added around Signal Recycling Mirror l Two options for signal recycling control u “Variable finesse technique” (Virgo-like) u Auxiliary lasers to lock the long cavities independently (LIGO-like) u Decision to be made by June March 15 th, 2019 13

+ l Higher Laser Power Moderate power increase in O 4 u Probably < 50 W (TBD) l Options u Stay with present laser » 100 W solid state amplifier installed in 2018 u New fully fibered laser » New fiber developed recently (unknown), phospho-silicate → photo-darkening free March 15 th, 2019 14

+ l Frequency Dependent Squeezing Squeezed vacuum source: two options u In air source (in kind contribution from AEI) u In vacuum source (developed by CNRS/LKB) l l 300 m filter cavity Two suspended injection benches March 15 th, 2019 15

+ l l Newtonian Noise Cancellation Use array of seismic sensors to cancel Newtonian noise Arrays deployed on site and in the end stations Main results: seismic noise near the test masses dominated by infrastructure noise Need to work on the HVAC system (part of the Ad. V+ project) March 15 th, 2019 16

+ Preparation work for Phase II March 15 th, 2019 17

+ l High Power Laser High power laser in O 5: 200 W u Two options based on fiber lasers » Coherent Beam Combination (CBC) » Amplifier based tapered fiber March 15 th, 2019 18

+ l Large beams Two options u Enlarge beams both on End Mirrors and on Input Mirrors u Enlarge beams on End Mirrors only l First option has strong impact on many subsystems u Vacuum, Injection, Detection, Bench suspensions, etc l Cavities stabilities is also an issue to consider March 15 th, 2019 19

+ l Large mirrors & LMA upgrade Large mirrors u 55 cm diameter (like the Virgo BS), 20 cm thick, 100 kg l Several changes to be done at LMA u New bench for measuring roughness and defects u Clean room extension u New handling tools u New mirrors mounts u Cleaning machine modification u Absorption and CASI modification u New spherical reference l Coating machine OK but u Uniformity on Ø 500 mm u Single rotation u Mirrors made one by one March 15 th, 2019 20

+ l Large payloads Payload installation u Handling tools for large mirror l Super-Attenuators load capability to be increased u Filter structure load capability to be checked u Blade springs and wires to be resize March 15 th, 2019 21

+ l l Coating R&D Alliance of LMA and several laboratories of the collaboration Goal: reduce coating losses by factor of three March 15 th, 2019 22

+ Status of the project l Advanced Virgo+ proposed in 2017 Now under review First funds expected in the second half of 2019 Phase I to be funded in 2019, 2020 and 2021 l Project management just established l An ambitious schedule Many works to be done Plan of priorities to be established l l l March 15 th, 2019 23