ABOUT CALIBRATION

1
ABOUT CALIBRATION
2
November/December calibration (1)

• Issues before november
• Free Michelson calibration
• NE 13.74 0.34 µm/V
• WE 12.14 0.30 µm/V
• Recycled ITF calibration line ratio
• NE/WE 1.38 _at_ 100 Hz
• NE/WE 1.43 _at_ 350 Hz

? NE/WE 1.13
3
November/December calibration (2)
Comparison of the currents in the up and down
coils of the WE mirror

• After DAC change
• Both channels within 3.5
• Calibration line ratio WE/NE 0.10,
• compatible with gain calibration

Investigations end of November ? DAC issue !
4
November/December calibration (3)
High Power actuator gain measurements -- Free
Michelson configuration (High Power mode) ? gain
decrease with frequency
NE tower
To do Check new HrecMichelson ? Measure the TF
phase also
5
November/December calibration (4)
Low noise actuator gain measurements -- locked NE
cavity (HP/LN) configuration
? Still to be confirmed and analysed
Variation of actuator gain vs frequency , and
coil driver mode ? ? Understanding of the
coil driver TF ? Other
6
Coil driver synoptics (end towers)
zCorr zCalib
6 kO
7
TF model of the coil drivers

• High power mode (end towers)

10 µs
??
??
10
8
TF model of the coil drivers

• Low noise mode (end towers)

10 µs
??
??
10
WARNING Emphasis/De-emphasis not yet corrected
in the following results !
9
NE TF in High Power mode (1)
Coherence
Measured TF
Corrected TF
Modulus
Modulus
Ca_NE_RM_Coil Vs Sc_NE_zCorr

• White noise injection ? 1 kHz
• Red/black up/down channels
• Modulus compatible with model 10 errors ?
• Phase too much delay

Phase
Phase (rad)
10
NE TF in High Power mode (2)
Coherence
Measured TF
Corrected TF
Modulus
Modulus
Ca_NE_RM_Coil Vs Sc_NE_zCorr

• Reduced the model delay by 140 µs (black channel)
• Phase within 1 from 0
• (should use 150 µs for the red channel)
• ORIGIN of the missing delay ?

Phase (rad)
Phase
11
NE TF in Low Noise mode (1)
Coherence
Measured TF
Corrected TF
Modulus
Modulus
Ca_NE_RM_Coil Vs Sc_NE_zCorr

• Step 12 data
• Red/black up/down channels
• Modulus
• Missing gain 730
• compatible within 10
• Phase missing delay

Phase (rad)
Phase
12
NE TF in Low Noise mode (2)
Coherence
Measured TF
Corrected TF
Modulus
Modulus
Ca_NE_RM_Coil Vs Sc_NE_zCorr

• Additionnal delay 170 µs (black channel)
• Additionnal gain 750
• Phase within 7 from 0
• ORIGIN of the missing delay and gain ?

Phase (rad)
Phase
13
WE TF in Low Noise mode

• Same results for the WE coil TFs
• Additionnal delay 170 µs
• Additionnal gain 750
• (note that the up and down channels are in phase
  opposition...
• Alain corrected it yesterday 11/01/07)

Ca_WE_RM_Coil Vs Sc_WE_zCorr
14
Divers

• Sauvegarde des données de calibration de
  novembre/décembre
• À Cascina /data/procdata/bufferv2/calibration
• À Lyon, sur hpss
• Création dune base de données calibration ?
• temps GPS, configurations des données
• mesures des gains des actionneurs
• Temps GPS des données calibration WSR
• (bruit blanc(NE/WE), données sans
  injection)
• Fréquence/Amplitude lignes de calibration par WSR

15
Divers

• Modifications du module Cali
• Classement des fichiers (TF, sensibilité,
  horizon) par année et par mois dans
  /virgoData/Cali à Cascina
• TF et sensibilité sauvées en ROOT, vect et ASCII
• Possibilité de sauver les fichiers dans un
  répertoire personnel en argument
• ? à mettre online (mais arguments modifiés)
• Note calibration des actionneurs en cours de
  rédaction