status of the virgo commissioning g.losurdo – infn firenze/urbino for the virgo collaboration

Status of the Virgo Commissioning

G.Losurdo – INFN Firenze/Urbino

for the

Virgo Collaboration

ILIAS WG1 – Perugia, September 19, 2005 G.Losurdo – INFN Firenze-Urbino 2

Since last meeting…

‘Jumps’ disappeared

Two runs:– C6 run: 29 Jul-12 Aug – C7 run: 14-19 Sep

Big improvement in stability and sensitivity

C6 and before

(June-July 05)


Actions before C6

IB aligned on the position of May 19-26 (when no jumps were present). No more changes since then (except ABP offset during C6)

B2_3f phase detuned by 75° from “optimal” phase Photodiode centering

Jumps disappeared

NE autoalignment using B1p (HH talk) Alignment drift control Improvement of SSFS loop

ITF more stable

‘ technique’ implemented


Laser0

+

-

Control of the differential mode

B5

BS

B5_ACp

B5_ACq

B1_ACp

B2_3f_ACp

Subtraction of BS control noise by the correction sent to the end mirrors

+

-

” technique”


Actions during C6

C6 sensitivity has been improved twice:

Spurious beam damped on NE bench

Change of power stabilization setup (use error signal after MC)


0 5 10 14days

Recycling cavity power

C6


C6 vs C5

(PR pwr *BS_AR)/(injected pwr*10)

C5 (no drift control)

C6 (drift control)


Duration: 336h

Locking: 89.3%

Science mode: 86.2%

C6 Duty cycle


C6 lock statistics


C6 sensitivity


C6 inspiral range

04/08(15:00 LT):

spurious beams damped on NE bench

04/08(15:00 LT):


10/08 (14:00LT):

laser beam re-aligned on the IMC

10/08 (14:00LT):


11/08 (15:30LT):

laser power stabilization reconfigured

11/08 (15:30LT):


GPS: 807818236 ( 297kPc)

GPS: 807842186 ( 300kPc)

GPS: 807818236 ( 297kPc)

GPS: 807842186 ( 300kPc)

04/08(15:00 LT):


04/08(15:00 LT):


10/08 (14:00LT):


10/08 (14:00LT):


11/08 (15:30LT):


11/08 (15:30LT):


GPS: 807818236 ( 297kPc)

GPS: 807842186 ( 300kPc)

GPS: 807818236 ( 297kPc)

GPS: 807842186 ( 300kPc)

04/08(15:00 LT):


04/08(15:00 LT):


10/08 (14:00LT):


10/08 (14:00LT):


11/08 (15:30LT):


11/08 (15:30LT):


GPS: 807818236 ( 297kPc)

GPS: 807842186 ( 300kPc)

GPS: 807818236 ( 297kPc)

GPS: 807842186 ( 300kPc)

0.14

0.42

0.28

Best range: 0.4 Mpc


Improvements during C6

Sensitivity from Jul 29 Sensitivity from Aug 12

Suppression of the non stationary

bumpPower noise

reduction

• Improvement of B1 optical gain (better alignment conditions ?)

• B1 electronic noise reduced by 2 (all the power sent to only one photodiode)

• Slight reduction of frequency noise (alignment ?)


Stray light

Stray beams in the NE external bench.

3 dumped, the bump disappeared !

Effect of stray beams dumping on B1_ACp RMS (in the bump region)

Coherence of dark fringe and NE bench photodiode:before and after dumping


Mode Cleaner transmission

Power stabilisation loopJuly 29 : Sensitivity limited by power noise due to beam jitter before the IMC

Improvement of the beam alignment on the IMC

Improvement of the power stabilisation loop (error signal taken after the IMC)

End of the run : the coherence between B1 & angular error signals of MC mirror disappears.

Jul 29 Vs Aug 12

Power noise


Noise budget

After C6

(mid Aug-mid Sep 05)


Actions after C6

10 AA loops closed (HH talk)

Full hierarchical control implemented

New B5 setup (more power on B5, less frequency noise)

Tidal control on BS

Coil driver upgraded to reduce DAC noise

New PR control filter

Important achievements:

Anderson technique demonstrated

SA control design demonstrated

ITF left locked during night !


Frequency noise limits the sensitivity above 1kHz It is due to B5_d1 shot+electronic noise which is introduced by the SSFS This noise can be reduced if a bigger fraction of B5 is sent to B5_d1

Sensitivity Aug 12thB1 shot noise

B1 elec noiseFrequency noiseIncoherent sum

Frequency noise


B5 setup modification

50 %

2f

50 %

Data in WPr_B5_DC,AC

d1

d2

50 %

50 %

90 %

quadrants10 %

Data in WPr_B5_2f

10 %

2f

90 %

Data in WPr_B5_DC,AC

d1

d2

90 %

10 %

95 %

quadrants5 %

Data in WPr_B5_2f

Old setup New setup

Now B5_d2 is used for SSFS, with 3 times more power (80% instead of 25%) Expected reduction of the frequency noise by a factor 2


B5 electronic and shot noise converted into a laser frequency noise by the SSFS loop

New optical setup : the SSFS error signal receives 3 times more power

Laser frequency noise should be decreased by 2 wrt C6

- B1_ACp, end of C6- B1_ACp, Aug 23 (new setup)- Shot + electronic noise- Electronic noise

Edwige Tournefier Aug 27

Laser frequency noise has been reduced but coherence with B1 still visible

Laser

0B5_ACp

Laser frequency control loop (SSFS)

B5: results


DAC noise

“Simple” DAC noise estimation does not explain the noise (50-150 Hz) in the 27 Aug sensitivity

DAC noise larger when correction applied

R.Gouaty


Hierarchical control


zCorr reduction

Marionette/RM crossover @5 Hz

After reallocation zCorr rms reduced by 100

Without marionette700 nm rms

With marionette7 nm rms


Automation

5 mins

Lock to DF variable finesse

AA ONOMC lock

MarionetteLow noise CD

techniqueLines ON


M9 – Aug 25

Marionette +NE/WE coil driver upgrade

New PR filter

New B5 setup

Turbo pump DETswitched OFF


BS DAC noise

BS DAC noise limits the sensitivity

Reduction of coil driver gain requires tidal control

Tidal control required!


M9 inspiral range

0.2

0.4

0.6MPc

Best range: 0.6 Mpc


Reliability

ITF stayed locked for 28 hrs with 10 dof AA ON, full hierarchical control, tidal control on BS


After M9

BS coil driver upgrade

Low gain LC

Aug 27


27 Aug inspiral range

0.6

0.8

0.7

Best range: 0.85 MpcMpc


Non stationarity

Probably due to diffused light on the end benches


Sensitivity from Aug 12 (End of C6)

Sensitivity from Aug 27Improvement due to Linear Alignment (4 loops closed

instead of 2)

DAC noise reduction

PR z control noise reduction (Neo

filter with roll-off @ 100 Hz)

BS z control noise : alpha tuning

New optical setup for B5 Reduction of laser frequency noise

2kHz bump due to detection tower pump (exciting external bench resonances)

August summary


Modulation depth

Modulation depth has been increased by a factor 2 (now m = 0.3)

PRCL control noise reduction expected

Tuning of the locking parameters needed

C7 run

14-19 September


C7 run

Many new features:– AA– Hierarchical control– Tidal control on BS– Coil driver upgraded– New B5 setup– Modulation depth increased

We decided to make a short run (5 days) before shutdown


C7 vs C6 sensitivity


C7 inspiral range

Best range: 1.65 Mpc


C7 duty cycle

Locked: 70%Science mode: 64%


C7 lock statistics


Hardware injections


Progress summary

status of the virgo commissioning g.losurdo – infn firenze/urbino for the virgo collaboration

Documents

losurdo infn firenzeurbino

ilias wg1 perugia

c6 sensitivity slide

c6 c6 sensitivity

kpc gps

losurdo infn firenzeurbino

laser beam re

mc slide