Flaminio Commissioning latest opearation

CITF Commissioning:latest operations: 

CITF Commissioning: latest operations Raffaele Flaminio

CITF configuration during E3: 

CITF configuration during E3

E3E4: Injection integration: 

E3E4: Injection integration

Injection integration: goals: 

Injection integration: goals Learn how to work with the full system Improve the sensitivity (if possible) Check if there are bugs in the injection-interferometer interfaces are there changes to be made for Virgo ?

Injection system control: 

Injection system control Sc_IB_zErrGC Bs_LA_MaFrqCorr Sc_IB_TxErrGC Sc_IB_TyErrGC Sc_MC_tyCorr Sc_MC_txCorr Sc_MC_zCorr IMPORTANT: recent changes in injection electronics  some of the IMC signals are under Sc_IC and Sc_MC

Injection beam alignment: 

Injection beam alignment Decision to mount detection Brewster on injection tower (to speed up planning) Picomotors reliability: decision to leave injection system in air during alignment Main problems: difficulties with injection locking while in air picomotors remote control not available Main findings: He-Ne laser very useful during alignment (need to have it permanently) several cameras looking at the input bench very useful (need to have them permanently)

Injection beam alignmentvsInjection system alignment: 

Injection beam alignment vs Injection system alignment Standard injection system alignment procedure: 1) manual alignment of laser beam to input bench (using reference cavity) 2) optimization of IMC transmission using mode-cleaner mirror alignment 3) mode-cleaner mirror automatically aligned with wave-front sensor 4) laser beam automatically aligned to reference cavity with wave-front sensor Main result: injection beam alignment can change by 100-300 mrad if standard injection alignment procedure was applied  decision to change injection alignment procedure: no manual re-alignment of reference cavity

Injection sensitivity to Interferometer reflection: 

Injection sensitivity to Interferometer reflection Injection system de-locks when PR mirror is aligned ! Spurious signals visible on reference cavity and mode-cleaner error signals (cavities reflected beam) Fringes visible on input mode-cleaner transmitted beam (no fringes visible on reference cavity transmission) Due to diffused light on mode-cleaner mirror or on input bench ? (beam incident on mode-cleaner mirror at 500 mrad) Problem never observed on other experiments (LIGO, TAMA, GEO) thanks to presence of one or more Faraday isolators

Interferometer locking: 

Interferometer locking Interferometer locked acting only on mirrors (mid June) - lock acquisition improved with stronger (and noiser*) qx feedback on PR - bandwidth ~ 30 Hz on WI, 70 Hz on PR * See E.Majorana talk Pr_B5_ACp Pr_B1p_ACq Pr_B1_ACq

Double loop trials: 

Several schemes proposed (Ex: standard VIRGO topology, TAMA like topology, …) 1) all large bandwidth’s ruled out by mode-cleaner bench resonance’s 2) trials with small bandwidth feedback to mode-cleaner bench fails One of the reasons to change Mode-Cleaner bench into a standard suspension Double loop trials

Linear alignment: 

WI mirror alignment control using quadrant on dark fringe beam Noise performances better than before (see E.Majorana talk) Feedback characterization unity gain ~ 5-10 Hz Instability at 17 Hz (seen during E3 and identified as a qz resonance) corrected with notch New linear alignment matrix measurements performed (see G.Giordano talk) Linear alignment Qr_B1p_q2_ACqh Qr_B1p_q2_ACqv

OMC locking: 

OMC locking OMC locking gain adjusted to larger power (~50 mW on dark fringe) OMC lock acquisition problem due to bad polarization in dark fringe beam c2 good even if OMC not resonant on TEM00 mode Effect due to p-polarized light - corrected by adding polarizer in front of the photodiode

Dark fringe control switch: 

Dark fringe control switch Dark fringe control switched from B1p to B1 Offset between B1p and B1 dark fringe on B1p  dark fringe on B1 Lock was lost during switch need to improve the switch in the software Problem empirically solved with misalignment of PR mirror before switch

Interferometer characterization: 

Interferometer characterization Input power ~ 2 - 2.5 Watts Recycled power (maximum) ~ 240 Watts Not coupled light ~ 30 % (~20% due to beam mismatching/misalignment, ~10% due to reflectivity mismatching) Modulation index ~ 0.04 (0.1 expected) Losses inside the interferometer ~ 0.8 % Interferometer contrast ~ 5 10-4 (B1p) , ~ 5 10-5 (B1)

Sensitivity: first result: 

Sensitivity: first result Noise due to frequency noise

Effect of injection local controls: 

Effect of injection local controls Local control OFF on input bench (x, y, z) and mode-cleaner mirror (x, y, qz) Control gain reduced on mode-cleaner automatic alignment

Sensitivity: OMC locked anddark fringe locked to B1: 

Sensitivity: OMC locked and dark fringe locked to B1

E4 run: sensitivity: 

E4 run: sensitivity Frequency noise To be investigated

Conclusions: 

Conclusions Integration of injection system into the CITF achieved A lot of experience made, many bugs discovered Final sensitivity: 10-13 m/Hz @ 10 Hz and better than 10-16 m/Hz @ 1 kHz Limiting noise identified over a large part of the spectrum (off-line removal in progress) Use of injection reduced considerably duty cycle Sources of lock losses are identified (see M.Barsuglia talk) More detailed results expected from this meeting

Agenda: 

Agenda 9h15 CITF commissioning: last results R.Flaminio (20') 9h35 Summary of E4 run M.Barsuglia (20') 9h55 Data conditioning B.Mours (20') 10h15 Calibration & Recostruction O.Veziant (25') 10h40 Break 11h10 Noise stationarity and gaussianity E.Chassande-Mottin (20') 11h30 Locking performances I M.Barsuglia (15') 11h45 Locking performances II S.Braccini (15') 12h00 Alignment performances I E.Majorana (15') 12h15 Alignment performances II G.Giordano (15') 12h30 Suspension performances I S.Braccini (15') 12h45 Suspension performances II V.Dattilo (15') 13h00 Lunch 14h30 Photodiode noise R.Flaminio (15') 14h45 Environmental noise I R.DeRosa (15') 15h00 Environmental noise II I.Ferrante (20') 15h20 Laser noise R.Barrile (20') 15h40 Glitches identification I E.Tournefier (15') 15h55 Glitches identification II D.Verkindt (15') 16h10 Lines identification A.Pai (20')