Experimental tests of SA simulation Irene Fiori – Simulation Workshop – March 18, 2004 Virgo dataSiesta simulation 1. Inertial Damping simulation  test with Real Seism (the Sea-storm) 2. Marionetta  Mirror TF  ITF Lock from marionette

Inertial Damping Seism Reduce the SA motion below  2Hz (in particular at resonances …. IP resonance  30mHz, chain resonances  200mHz ) Helps for Lock acquisition (together with mirror Local Controls) F0 ACCELEROMETERS POSITION SENSORS (LVDTs) COIL-MAGNET C Corr Lvdt_x Acc_x (similar on z,  y ) x z F0 top view: yy (force on F0_x) + x z F0 top view: Err

H L L+H=1 5 Hz Open loop gain: Filters:

The code : MIsa SuNI 0 Sisma.out "ni_tuned.sad 0 dampTotal damping.out "defaults" UJclock masterClocks UFrIFile input 1../mareggiata_guralp/guralpdispl_full_200hz.gwf UFrDump 1 input.frameH UFrUnpack Sisma_mare 0 proc.Guralp_displ input.frameH US6Set Sisma 0 Sisma_mare.out Sisma_mare.out Sisma_mare.out NULL NULL NULL /* */ /* NEW Inertial damping GENERIC tower (A.Vicere, I.Fiori, G.Losurdo) */ /* */ USfilterZPK hp1_acc_s0 SuNI.dxyzt.s USfilterZPK …. US6Set damping 0 viscous_s0.out NULL viscous_s2.out NULL viscous_s4.out NULL USadder error_s2 0 2 lvdt_notched_s2.out hp_acc_s2.out …..

Mirror motion ID on / off, with nominal seism (…only with Simulation!)

SA modes Real vs Siesta Resonances F0 cross bar Siesta “nominal” SA tower (not simulated yet)

F0 horizontal modes (poles) [ Hz ] BS towerSiesta (% deviation) (+3%) (+2%) (+7%) (-2.5%) (-2%) (+2.5%) (+1.9%) (+1%)

Ground Seism in Siesta Real Seism (SEA-STORM) Nov. 16, 2003 (C1 run) y x z

Inertial damping (C1) Simulation fed with REAL SEISM of SEA-STORM on Nov. 16, 2004 (C1) Quiet seism (data) F0 position sensor Sensor electronic noise

Inertial damping (C1) Real data Siesta F0 cross-bar Simulation fed with REAL SEISM of SEA-STORM on Nov. 16, 2004 (C1) F0 accelerometer m/s^2/sqrt(Hz) Accelerometer Noise not Simulated, here

New local controls reading marionette position: a tilted mirror couples a  z resonance to  y (300 mHz). This resonance is not controllable: we do not have  z actuators A storm during C1 caused an increase of seismic mHz of about 100  Big excitation of the  z resonance (coupled with  y )  Loss of lock A new mathematical solution (L5 damping) has been found that allows to: –Move the blending down to 70 mHz preserving the phase margin –Rolling off the LVDT as 1/f 3 New Inertial Damping for C2 run (from G.Losurdo) …..

New Inertial Damping (C2) Siesta prediction F0 accelerometer response, with Nov. 16 SEA-STORM Seism Accelerometer electronics noise

New Inertial Damping (C2) “fortunately” a new, even bigger, sea-storm occured during C2 … C2 C1 Ground seism

Marionetta  Mirror A good simulation of the Marionetta 2 Mirror mechanical TFs is important for implementing simulation of: mirrors Local Controls (  x and  y ) ITF Linear Alignement (  x and  y ) ITF Lock acting from the Marionette (z)

Marionetta  Mirror (z) Siesta, since v3r88 1/ f 4 Measured (Luciano)

Marionetta  Mirror (  y) Siesta Measured

Marionetta  Mirror (  x) Siesta  TM wires: 400  m 200  m Measured NOW

Marionetta Z modes [Hz] MeasuredSiesta (P) (+1%) (Z) (+1.5%) (P) (+0.5%) (Z) (-2%) (P) (+0%) (ZP) (-0%) (ZP) (+0.7%) (P) (+0.5%) (Z) (P) (Z) (-4%) (P) (-2%) -(Z) (P) 1.08 (Z) (0%) (P) (0.8%) (Z) (P)  y modes [Hz] MeasuredSiesta (P) (+0.3%) (Z) (-0.9%) (P) (-0.6%) (Z) (-2%) (P) (-0.7%) (Z) (-0.3%) (P) (-1%) (P) (-3%)  x modes [Hz] MeasuredSiesta (P) (+1.7%) (Z) (-0.2%) (P) (+1%) (Z) (+0.5%) (P) (-3.8%) (Z) (+7%)

ITF Lock with Marionetta What is there :What is still missing : C Noise DAC  dL B1p_quad B7_DC Seismic noise (5.E-8 / f 2 ) Inertial Damping (v.C2) Actuators (F7): 8.8Hz pole, DAC noise, saturation Higher modes (now TEM00) Control mirror Tx, Ty Noises: shot, thermal, laser tuning of Mario resonances B7 B1 seism F7 coil (I.Fiori, A.Gennai, G.Losurdo)

Compensator f 4 25 Hz G  2E+5  45°  f -2 (f 3 )

Linear Locking (from Marionetta) 0.1% “Lock Quality” similar to standard-lock simulation

Lock Transition: Mirror  Mario Err Coil RM 480 Hz) Anti- TRIGGER Coil F7 8.8 Hz) x TRIGGER Ramp 10s x DAC noise (300nV/sqrt(Hz)) DAC noise (300nV/sqrt(Hz)) Err_mario Err_lisa RM coils DAC noise turned OFF

Lock Transition: Mirror  Marionetta 10s RAMP

Sensitivity curve Can improve the compensator (lower unity gain)

Conclusions SA Siesta simulation being tested against data, with good results most SA resonant modes reproduced within < few % tower by tower tuning, in progress. Implementation/validation of SA control loops, in progress: SA Inertial Damping Mirror local angular controls Mirror Linear Alignement (Tidal control) More complex Siesta simulations (ITF locking) also demonstrate SA simulation works satisfactory Siesta simulation being used to test/design Virgo controls