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Piero Rapagnani Department of Physics, La Sapienza & INFN, Sez. Roma On behalf of the Virgo Collaboration LIGO-G060281-00-Z. Status of Virgo. EGO. LAPP - Annecy INFN - Firenze/Urbino INFN - Frascati IPN - Lyon INFN - Napoli OCA - Nice. ESPCI - Paris LAL - Orsay INFN - Perugia
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Piero Rapagnani Department of Physics, La Sapienza & INFN, Sez. Roma On behalf of the Virgo Collaboration LIGO-G060281-00-Z Status of Virgo ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
EGO • LAPP - Annecy • INFN - Firenze/Urbino • INFN - Frascati • IPN - Lyon • INFN - Napoli • OCA - Nice • ESPCI - Paris • LAL - Orsay • INFN - Perugia • INFN - Pisa • INFN – Roma NIKHEF – Amsterdam (joining) Inaugurated July 2003 ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Plan of the talk Virgo layout Activity after C6/C7 and present status Next VIRGO runs VIRGO+ Advanced VIRGO ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Input Mode Cleaner 3 km long Fabry-Perot cavities: to lengthen the optical path to 100 km Output Mode Cleaner Virgo Optical Scheme Laser 20 W Power recycling mirror: to increase the light power to ~1 kW ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Thermal noise Free falling test masses ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Keep the FP cavities in resonance Maximize the phase response Keep the PR cavity in resonance Minimize the shot noise Keep the output on the “dark fringe” Reduce the dependence on power fluctuations Keep the armlength constant within 10-12 m ACTIVE CONTROLS NEEDED ITF Operation Conditions…see also Losurdo talk on Wednesday LOCKING ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
IP displacement Hierarchical Control DC-0.01 Hz Tide control 0.01-5 Hz 5-50 Hz • Force reallocation over three actuation stages. • Allows strong reduction of the force exerted on the mirror • After reallocation, reduce the actuators gain ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Shut down: end of September 05 New injection bench: Toward the nominal power Full redesign Faraday isolator New Input Mode cleaner alignment scheme New Recycling mirror Go to a monolithic mirror (flat geometry) Change the input telescope Use parabolic mirror on the “injection bench” Adjusting the reflectivity (92%-95%) increase of the recycling factor 750W expected on the beam splitter x30 compared to C7 Back to vacuum: end of November 05 Activity after C6/C7 Old New ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
December: Realign the injection system Restart the local controls January Relock the input mode cleaner (5 Jan 06) Realign the input telescope Measure TF for the new recycling mirror. February Relock the long cavity 95% beam matching up to now Relock the reference cavity March Relock the full Virgo Slow down by the usual problems: Alignment, broke a translation stage, pico-motors, faulty electronics,… Virgo re-commissioning (see also H.Heitmann talk…) ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Virgo locking scheme: Variable finesse technique (described in detail in Heitmann talk): Lock on the half fringe Used transmitted beam to lock the cavities Start the frequency stabilization servo Align PR mirror Fringe offset adiabatically reduced Use different error signals At present ITF relock: PR aligned Dark fringeachieved Power in the arms greater by a factor 10 than before shutdown still a factor ~3 to go B8p L1 Starting Step Recycling Misaligned ITF on Grey Fringe L2 B2_3f_ACp l1 B7p l0 l2 B1p_DC Virgo status now ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Interferometer control ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Virgo commissioning started in 2003: fast progress, approaching design sensitivity NS/NS maximum range 1.5 Mpc ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
2006 Interferometer restart: next month Noise hunting (see the talks by E.Cuoco and F.Paoletti) First Science Run in autumn (NS-NS horizon around 15/2.5 Mpc?) 2007 A possible shutdown to fix problems Commissioning and noise hunting Nominal sensitivity Data taking > 50% of the time ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
-18 10 -19 10 h (Hz-1/2) Pulsars hmax – 1 yr integration LIGO -20 10 Virgo -21 10 Resonant antennas GEO BH-BH Merger Oscillations -22 10 @ 100 Mpc Core Collapse QNM from BH Collisions, @ 10 Mpc QNM from BH Collisions, 100 - 10 Msun, 150 Mpc 1000 - 100 Msun, z=1 -23 10 BH-BH Inspiral, 100 Mpc NS-NS Merger Oscillations @ 100 Mpc BH-BH Inspiral, z = 0.4 -24 10 -6 e NS, =10 , 10 kpc 4 1 10 100 1000 10 NS-NS Inspiral, 300 Mpc Hz First Generation Detectors ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Waveform accurately predicted: VIRGO/LIGO can detect a NS/NS event as far as 30 Mpc Uncertain event rates. Calculated by: statistical analysis (observed binary systems) theoretical investigations (population synthesis, evolution models) How Many Events? COALESCING COMPACT BINARIES [Burgay et al., 2003 - Nutzman et al., 2004] ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Seismic Thermal Shot After 2007: Expanding the Accessible Universe: Where and how can we reduce the detector noise? ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Virgo will be upgraded with a set of medium scale, low cost (~1-2 MEuro), incremental improvements with: Compatibility with the main Virgo subsystems (“plug and play”), same optical layout Limitedshutdown Limited commissioning time Four independent items have been identified: Monolithic payloads with fused silica suspensions New laser, 50 W Mirror thermal compensation Electronics and control system upgrades To be installed after design sensitivity has been reached and a long data taking has been performed Virgo+(see also M.Punturo Talk on Wednesday) ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Depending on thermal noise model Newtonian noise Virgo+ Sensitivity (a) fbulk= 10-7 [Virgo design model] (b) fbulk= 10-9[Penn et al. 2005] Inspiral Range: averaged orientation (optimal orientation)[Mpc] ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
GOAL: pendulum thermal noise reduction Fused silica fibers technology well established and adopted at GEO Change of reference mass material from metal to dielectric Engineering started: Fibers production facilities being installed @EGO (H2O2 Perugia, CO2 laser Glasgow) Installation of the payload infrastructure for assembly (Roma) Production of a dummy payload (Perugia,Roma) Definition of a safe hanging procedure to be defined Safe control strategy to avoid fatal shocks to be defined Payload handling: cleaness and transport 1. Monolithic payload ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
GOAL: reduce shot noise / reduce laser unlocks rate Limited power increase (50 W) allowed if input optics unchanged (in any case we need to analyse carefully the input optics response in view of the increase) Technology for high power laser suitable for advanced detectors almost ready ( collaboration with GEO is crucial for VIRGO) 2. Laser 3. Thermal compensation • GOAL: improve the spatial overlap between the carrier and sidebands spots spoiled by mirror thermal deformation • Technology is mature: heating rings used at GEO, CO2 laser at LIGO • VIRGO-Napoli et al. coordinate the construction effort 4. Electronics • GOALS: • Reduce control noise • Cope with the increasing complexity of the needed control strategies • Pisa/Annecy/EGO R&D project in progress: • New DSP board • New ADC with higher sampling frequency (60 kHz) and more bits • New actuation electronics (DAC with more bits, low noise coil drivers) • New communication board (10x faster), New timing board ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
2005-2007 Possible implementation of some short term upgrades (electronics, thermal compensation) Working groups activity Technical design (end 2007) 2008 Implementation of Virgo+ Provisional schedule ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
2006-2007 Working groups activity Signal Recycling High Power New optics and optical configuration Technical design 2008-2009 Engineering activities for Advanced Virgo > 2010 Advanced Virgo upgrades Advanced VIRGO ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
Advanced VIRGO vs VIRGO+ Plaser after IMC = 100 W, mirror weight = 40 kg, PR gain = 50, finesse = 600 Credit: M.Punturo NS-NS NS-BH BH-BH SNe Event Rate (per year) 0.025-10 10-3-15 3 10-2-90 1 Range (Mpc)114 230 584 10 ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
h (Hz-1/2) Next Decade Network ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop
A hope for the near future: The Beginning of a New Astronomy… LIGO - Virgo LIGO+ - Virgo+ AdvLIGO - AdvVirgo ELBA GWDAW-VESF Meeting Gravitational Wave Advanced Detector Workshop