advanced virgo giovanni losurdo advanced virgo coordinator for the virgo collaboration
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Advanced Virgo
Giovanni Losurdo
Advanced Virgo Coordinator
for the Virgo Collaboration
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 2
ADVANCED VIRGO (AdV)
PROJECT GOALS Upgrade Virgo to a 2nd generation detector. Sensitivity: 10x better than Virgo Be part of the 2nd generation GW detectors network. Timeline: in data taking
with Advanced LIGO
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 3
MAIN REQUIRED UPGRADES
Signal Recycling (SR)
Non degenerate rec. cavities
200W laser
Higher finesse3km FP cavities
Heavier mirrors
Waist in the cavity center
Larger central linksCryotraps
Monolithicsuspensions
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 4
TUNEABILITY
AdV can be “tuned”. Changing the SR mirror transmittance allows to shape the sensitivity curve
The tuneability can be exploited to optimize the detector for different astrophysical sources (BNS, BBH, millisecond pulsars,supernovae)
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 5
STEPS TOWARDS TARGET
The design sensitivity will be achieved in “steps”:
− The commissioning activity will start in “low power” configuration
− The opportunity of starting without SR will be considered
Even with low input power and without SR AdV can have a relevant science impact
BNS (Mpc)
BBH (Mpc)
h@1 kHz
AdV REF 149 753 1.8e-23
5 W in 117 1374 1.8e-21
30 W in 139 1004 1.6e-22
no SR 107 311 2.2e-23
DESIGN OVERVIEW
See “Advanced Virgo Preliminary Design”, VIR-089A-08
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 7
OPTICAL CONFIGURATION
MAIN FEATURES Signal recycling Non degenerate recycling cavities Larger spot on the mirrors
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 8
OPTICAL CONFIGURATION - SR
SIGNAL RECYCLING WHY?: Allows shaping of the detector sensitivity Requires one more SA (tower base available) Adds complexity, commissioning more difficult
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 9
OPTICAL CONFIGURATION -NDRC
NON DEGENERATE RECYCLING CAVITY WHY?: Avoid high order modes to be resonant
− much “cleaner” ITF dynamics
− reduces sensitivity to misalignments, thermal effects, ROC errors
− provides more control signals
Requires:− larger vacuum links
− extra seismic isolation for injection and detection benches
Promises to simplify commissioning
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 10
OPTICAL CONFIGURATION – SPOT SIZE
LARGER SPOT SIZE WHY?: Reduces mirror thermal noise
and thermal effects on input mirrors Requires larger vacuum links and
larger beam splitter
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AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 11
PRE-STABILIZED LASER
AdV laser to provide up to 200 W High power stage bases on the LZH design for the Adv LIGO laser Pre-stabilized in frequency and amplitude
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 12
INJECTION SYSTEM
Input mode cleaner: 144 m suspended triangular cavity Large Faraday isolator with thermal compensation (DKDP crystal) Non degenerate PR cavity: the matching telescope is moved inside the cavity.
The PRM and the folding mirror must be suspended on the injection bench
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 13
MIRRORS
HEAVIER TEST MASSES WHY? Cope with larger radiation pressure Require payload modification and silica fibers
optimization Reference design:
− 35 cm Ø, 20 cm thick, 42 Kg FP mirrors
− Flatness requirements: 0.5 nm
− Larger BS
− 2010 state of the art coating
Corrective coating might allow to further improve the flatness and give more flexibility
63 kg mirrors considered
− technically feasible, though payload modifications more risky
− science gain limited by newtonian/susp thermal noises
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 14
MIRRORS - FEATURES
All the choices needed to purchase the large test masses have been made. Some features of the small mirrors of the REC cavities TBD/TBC
TBD# 10 ppm
(TBC)# 10 ppm
(TBC)# 100 %50 %
# 10 ppm(TBC)
0.7 % (TBC)
TransmissionReflective side
3 nm RMS (TBC)
20 mm
3 nm RMS (TBC)
20 mm
3 nm RMS (TBC)
100 mm
3 nm RMS (TBC)
150 mm
3 nm RMS (TBC)
250 mm
0.5 nm RMS (TBC) 200 mm
0.5 nm RMS (TBC)
150 mm
RMS Flatness Reflective side
<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMSRoughness
Reflective side
50 mm50 mm50 mm100 mm (TBC)
65 mm200 mm 200 mmThickness
50 mm(TBC)
50 mm(TBC)
150 mm (TBC)
280 mm(TBC)
< 550 mm(TBC)
350 mm350 mmDiameter
Herasil 102Herasil 102Herasil 102Herasil 102Suprasil
3001Suprasil 312
Suprasil3002
Fused Silica Nature
3332244Number of
parts
PRM1/SRM1PRM2/SRM2PRM3/SRM3
Non degenerate Power and Signal recycling Cavities
Compensation PlateCP
Beam SplitterBS
End Mirror EM
Input MirrorIM
TBD# 10 ppm
(TBC)# 10 ppm
(TBC)# 100 %50 %
# 10 ppm(TBC)
0.7 % (TBC)
TransmissionReflective side
3 nm RMS (TBC)
20 mm
3 nm RMS (TBC)
20 mm
3 nm RMS (TBC)
100 mm
3 nm RMS (TBC)
150 mm
3 nm RMS (TBC)
250 mm
0.5 nm RMS (TBC) 200 mm
0.5 nm RMS (TBC)
150 mm
RMS Flatness Reflective side
<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMS<1 Å RMSRoughness
Reflective side
50 mm50 mm50 mm100 mm (TBC)
65 mm200 mm 200 mmThickness
50 mm(TBC)
50 mm(TBC)
150 mm (TBC)
280 mm(TBC)
< 550 mm(TBC)
350 mm350 mmDiameter
Herasil 102Herasil 102Herasil 102Herasil 102Suprasil
3001Suprasil 312
Suprasil3002
Fused Silica Nature
3332244Number of
parts
PRM1/SRM1PRM2/SRM2PRM3/SRM3
Non degenerate Power and Signal recycling Cavities
Compensation PlateCP
Beam SplitterBS
End Mirror EM
Input MirrorIM
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 15
MIRRORS - PRODUCTION PLAN
Detailed revised DRAFT Planning if starting on 01/07/2009: estimation based on real delay for the manufacturing of the silica and on the real time necessary for the VIRGO+ substrates polishing
Overall estimated time: 2 yrs + 9 mts
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 16
THERMAL COMPENSATION
WHY? Compensate for wavefront distorsion and test mass surface deformation
Reference design:
− Ring heater around test masses to correct for ROC
− CO2 laser to correct for wavefront distorsion on recycling cavities
− “Compensation plates” needed in front of input test masses
Compensation plates to be suspended from SA
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 17
DETECTION
DC READOUT WHY? To reduce shot noise by ~20% and the influence
of some technical noises Requires a new high finesse output mode cleaner
SUSPENDED DETECTION BENCH Must host the SR mirror and the folding mirror (with their suspensions) Must host the main photodiodes that need to be under vacuum
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 18
SENSING AND CONTROL
Reference design:
− Auxiliary laser to lock the high finesse cavities
− Extended Variable Finesse technique for full lock
− Requirements, a set of cavity lengths and mod. frequencies defined
− Linear control scheme defined
The reference control strategy requires to move all the long towers in the central building
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 19
SUPERATTENUATOR
Vibration isolation provided by the SA is compliant with AdV sensitivity
Main foreseen change: tilt control of the inverted pendulum (inertial platform controlled in 6 d.o.f.)
Tilt control allows to cope with wind generated tilt noise, that can spoil the inertial damping performance with bad weather conditions
Tilt actuation already foreseen in the inverted pendulum design (room for PZT at the base of the legs)
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 20
PAYLOAD
The heavier mirror requires to modify the payload Constraints:
− keep the payload weight the same as Virgo’s
− low electrical conductivity reference mass
A simplification of the “steering” part is being investigated (MRM)
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 21
MONOLITHIC SUSPENSIONS
Virgo+ fibers
Engineering of Virgo+ fibers well advanced:
− standardized production and reproducible geometry
− welding and clamping optimized
− flexure points controlled
AdV monolithic suspensions
− fiber geometry optimization: use of tapered fibers?
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 22
VACUUM – RESIDUAL PRESSURE
VIRGO RESIDUAL PRESSURE:
10-7 mbar (H2O+H2+HC), 100 worse than LIGO (bake-out)
Residual pressure noise would spoil AdV sensitivity: bake-out needed Need to separate tubes from towers
REFERENCE SOLUTION: CRYOTRAPS WHY? Allow to bakeout the pipes and
not the towers Major upgrade of the vacuum system
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 23
VACUUM – CENTRAL LINKS
NEW VACUUM LINKS IN THE CENTRAL AREA WHY?: lenghts to be changed, diameter to be increased
− the position of the towers will be changed by up to 1 m (ISC requirements)
− larger beam spot on the input test masses, folded beam path in non-degenerate recycling cavities, require larger diameter links
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 24
VACUUM - INFRASTRUCTURES
STRUCTURES INVOLVED IN HEAVY MODIFICATION WORKS
vacuum links
scaffoldings braces
cable trays
clean air ducts of the towers
H beams as links between the frames of the ovens
false ceiling of the CR Towers Gallery
DISPLACEMENT OF THE TOWERS IN THE CENTRAL HALL TO OPTIMIZE THE ITF CONTROL STRATEGY
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 25
INFRASTRUCTURES
Virgo sensitivity is spoiled by machine noise. Hard commissioning/detector work has been done to understand and reduce the couplings
AdV will be 10x as sensitive noise reduction required AdV approach: improve the machines isolation and move them far from the
experimental halls
ORGANIZATION
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 27
AdV STEPS
PHASE 1: AdV Conceptual Design (ended fall 07) PHASE 2: AdV Final Design (to end June 09) PHASE 3: AdV Construction PHASE 4: AdV Installation PHASE 5: AdV Commissioning
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 28
PHASE 2 ORGANIZATION
OSD – A.Freise
AdV coordinator – G.Losurdo
DAQ – R.De Rosa
VAC – A.PAsqualetti IME – A.Paoli
Task Manager
Task Manager
…
PAY – P.Rapagnani
SAT – R.PassaquietiTCS – V.Fafone
MIR – L.PinardDET – E.Tournefier
INJ – E.GeninLAS – N.Man
ISC – F.Bondu
VSCVirgo spokesman/EGO scientific dir.
EGO
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 29
Advanced Virgo Coordinator
From the Virgo Organization Document
The AdV coordinator coordinates the preparation for AdV. More specifically he is responsible of:
− Coordinating the activity of the AdV System Managers (SM)
− Coordinating the R&D activity for AdV.
− Coordinating the elaboration of the final design.
− Making sure that system design issues are worked out.
His goal is to reach a state where the AdV systems are ready for construction (mandate to end in Spring 09)
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 30
Subsystem Managers
OSD (Optical Simulation and Design) A. Freise (B’ham Univ.)
ISC (Interf. Sensing and Control) F.Bondu (OCA Nice)
LAS (Laser) N. Man (OCA Nice)
INJ (Injection system) E. Genin (EGO)
DET (Detection system) E. Tournefier (LAPP Annecy)
MIR (Mirrors) L. Pinard (LMA Lyon)
TCS (Thermal Comp. System) V. Fafone (INFN Rome 2)
SAT (Superattenuators) R. Passaquieti (INFN Pisa)
PAY (Payload) P. Rapagnani (INFN Rome)
DAQ (Data Acq. and Electronics) R. De Rosa (INFN Naples)
VAC (Vacuum) A. Pasqualetti (EGO)
IME (Infrastructures) A. Paoli (EGO)
The SM are responsible, within their subsystem, for:
− preparing the list of tasks, milestones and deliverables
− producing precise requirements/specifications;
− preparing the case for the selection of the open design options, including detailed planning and financial resources required;
− preparing a design and project execution plan, to be integrated in the updated AdV documents, and work out the task breakdown.
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 31
NEXT STEPS
If project approved and funded:
Start Phase 3 placing the order for the mirrors on July 2009
GOALS FOR MAY 09 (NEXT PROJECT REVIEW)
1. Release of the AdV final design
2. Updated cost plan and project execution plan
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 32
AdV COST
In fall 2007 the AdV cost was estimated in the “AdV PEP” (VIR-043A-07)
15.8 MEuro (equipment only)
Since then:
− New organization, subsystem managers in charge
− Relevant changes to the conceptual design
Some of the new design choices may have an important impact on the overall cost (non-degenerate cavities, anthropogenic noise reduction, need for bakeout, …)
Each SM is working to provide an accurate cost plan in the next months (some already have one). The AdV cost plan and spending profile will be presented before the spring review.
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 33
AdL: 2nd ITF accepted
DRAFT PLANNING
08 09 10 11 12 13 14 15 1607
PHASE 1: AdV conceptual design
PHASE 2: AdV final design
PHASE 3: AdV construction
PHASE 4: AdV installation
Commissioning
AdL: 1st ITF accepted
AdL: 3rd ITF accepted
×
place mirrors order
AdV 1st Project Review – Cascina, Nov. 3rd, 2008 G.Losurdo – AdV Coordinator 34
CONCLUSIVE REMARKS
A preliminary design of AdV has been released
The forthcoming talks by the subsystem managers will detail the status of the design and show the important progress achieved in the next months
The Virgo Collaboration will release the AdV final design and the updated cost plan before the spring 09 review
GOAL: being in the position to start the construction of AdV on July 1st 2009