SAT Plans for System R&D Signal Recycling Construction and A&I Short Suspension Upgrade Roberto Passaquieti Università di Pisa and INFN-Pisa AdV Review – Cascina, Nov. 3rd, 2008

AdV Review - November 3rd, The Virgo Superattenuator VIRGO Thermal Noise Filter Zero Standard Filters Inverted Pendulum Filter Seven Payload: Marionette Ref. Mass Mirror GROUND

AdV Review - November 3rd, SA Passive Attenuation Vertical Horizontal VIRGO Thermal Noise Measured Upper Limit

AdV Review - November 3rd, SA Passive Performance vs AdV VERTICAL HORIZONTAL 6 x m Hz -1/2 Upper limits of residual seismic vibrations along the beam are close to the VIRGO thermal noise Final systematic check in VIRGO +

AdV Review - November 3rd, Payload Swing Ground Seismic Noise Residual Mirror Seismic Noise Inertial Damping

AdV Review - November 3rd, Swing induced by resonances < 0.1  m Inertial Damping ADCDSPDAC Coil-Magnet actuators Acceleromters LVDT Ground Frame

AdV Review - November 3rd, Payload Swing Reduction Performance  Wide payload swing during windy days, when seismic noise below 200 mHZ is dominated by ground tilt  Too large correction dynamics for AdV requirements WIND SEA MARIONETTA CORRECTION  For principle reasons the ACC can not distinguish tilt affecting ID  A sensitive tilt-meter (≈ rad/ Hz 1/2 at ≈ 30 mHz) would be important  As demonstrated during VRS1 payload swing is ok during normal conditions but..

AdV Review - November 3rd, Present Marionette and Ref. Mass DAC Noise  Reference mass actuator noise is compliant with AdV AdV VIRGO  Marionette actuator noise has to be reduced for AdV by about a factor 10 in the Hz region (SAT R&D)

AdV Review - November 3rd, Marionette Actuation Range Optimization Calm Any  Marionette actuation range (and thus noise) can be already reduced by a factor 5, loosing only 1% of duty cycle  If tilt-meters will be put in action a calm condition on top-stage can be recovered, allowing at least a factor 8 reduction (by less 1% duty cycle) Volt

AdV Review - November 3rd, Marionette DAC Noise Reduction AdV starting point with a factor 5 DAC noise reduction AdV VIRGO

AdV Review - November 3rd, Present Performances vs AdV Specifications  Passive attenuation is OK  a new confirming test will be made in the next months  Payload swing is OK during normal environmental conditions  ID performance need to be enhanced during windy periods:  Tilt control as direct solution to reduce mirror swing below 200 mHz by a factor 10:  Operate high sensitive tilt-meters (difficult task) and piezo actuators  Investigate the possibility to extract the tilt signal combining the error signals of more SAs  Reduce actuation noise:  Selecting new low noise DAC (R&D: preliminary factor 1.5 obtained)  Splitting the action from only one to both cavity mirrors (factor 2)  Advanced filtering (enphaisis-de emphasis already tested on RM-Mirror)  Actuation optimization (factor 5 now)  Adaptive control strategy (new coil drivers with switch HN/LN config)

AdV Review - November 3rd, SAT Activities  SAT is called to make plans for the following activities:  Upgrade of the SA system (R&D activities):  Tilt Control:  Tilt-meters, piezoelectric actuators  Actuation noise:  ADC-DSP-DAC, Coil drivers  Upgrades:  Inverted Pendulum (IP)  Filter Zero (F0)  ACC, LVDT boards  Deliver plans for:  SR SA construction, assembly and integration  MC-DB-IB SAs upgrade

AdV Review - November 3rd, Tilt-Meter Status  Two Prototypes have been already assembled.  No problem in the electronics chain  Serious problems in the yielding of the flex joints (robustness).  New flex joint system mounted  Tests are being performed and will continue in the next months.

AdV Review - November 3rd, Piezoelectric Actuators Room for PZT accommodation Bottom ring Tilt meter  Tilt compensation was already addressed before VIRGO construction  Space for Piezos operation is already available on the bottom of IP platform

AdV Review - November 3rd, Piezoelectric Actuators Status  The three piezos P have been purchased.  The driving board is being prepared.  The installation in SA Facility at EGO (SAFE) is progressing

AdV Review - November 3rd, Inverted Pendulum  A new IP has been conceived.  Monolithic Al legs:  higher structural modes, more robust and safe for piezos operation  First IP prototype built and on site, ready to be assembled in SAFE

AdV Review - November 3rd, Filter Zero and Accelerometers  The F0 design is being investigated to displace to higher frequency the crossbar resonances (benefit to vertical ID)  Analysis of the F0 crossbar resonance effects is in progress to understand the impact on the interferometer  The ACC sensitivity ( a few m/s 2 / (Hz )1/2 above 1 Hz) is adequate for AdV VIRGO but a few actions are required  Obsolete electronics upgrades  Spares preparation  New digital control boards  New monolithic ACC is being investigated by the Napoli-Salerno Group

AdV Review - November 3rd, SAT R&D Activities Implementation Plan

AdV Review - November 3rd, SAT R&D Manpower

AdV Review - November 3rd, SR Construction, Assembly and Integration  The SR SA chain will be a complete long Superattenuator.  preliminary specs: (G. Vajente, “Requirements for the Advanced Virgo Length Sensing and Control System”, VIR-083-A, 2008)  VIRGO design + R&D upgrades  PBS, WBS, cost estimates and manpower plan has been conceived: SAT MANAGEMENT PLAN (Issue 1 ready): (“SAT AdV Plan for R&D, SR Construction and Short SA Upgrade” VIR-091A-,2008)

AdV Review - November 3rd, SR Construction, Assembly and Integration SR SA ITEM 1 St. Filt. ITEM 2 F0 ITEM 3 F7 ITEM 4 IP ITEM 5 Safety Frame ITEM 6 Susp. Wires ITEM 7 Cabling ITEM 8 Acceler ITEM 9 Tools

AdV Review - November 3rd, SR Production and Manpower Plan

AdV Review - November 3rd, SR Installation Plan

AdV Review - November 3rd, SR Costs Evaluation

AdV Review - November 3rd, MC-IB-DB Systems Upgrade  OPTION 1: One extra filter stage  1 FS, F0 blades, IP Flex joint, Cabling Reshuf.  OPTION 2: More than one extra filter stage (up to 4)  Opt.1 +n. FS, IP Legs, Safety Struct., Full Cabling.

AdV Review - November 3rd, MC-IB-DB Systems Upgrade Plans

AdV Review - November 3rd, MC-IB-DB System Costs

AdV Review - November 3rd, Summary of Management Plan SIGNAL RECYCLING SUSPENSION  Time: 9 Months for item preparation + 13 weeks for assembly  Persons: minimum of 7 physicists/engineers + 5 technicians  Costs: 327 k€ + electronics (130 k€ - detailed plan in progress) SHORT TOWER UPGRADES  Time: 7-11 months for items preparation + 13 – 17 weeks  Persons: minimum of 7 physicists/engineers + 5 technicians  Costs: 216 k€ (option1), 359 k€ (MC:1FS, IB 2FS, DB 2FS) 398 k€ (MC:1FS, IB 3FS, DB 3FS), 437 k€ (MC:1FS, IB 2FS, DB 2FS) + electronics (300 k€ TBD)