[Michimura, Komori]
We worked on the input mode cleaner (IMC), mainly wave front sensor (WFS).
Firstly slight works are reported.
1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.
3. Alignment of IMC mirrors are adjusted toward increasing the transmitting power, which results to be 0.46 from 0.35.
At that time the values of IN_MON were as below.
Pitch Yaw
MCI -11.5 0.2
MCO 9.5 4.4
MCE 1.0 -2.9
We tried to control mirrors of IMC by oplev, but the lock is down when oplev control turns on with drift.
Secondly we report working on WFS.
The signal of alignment of IMC mirrors is taken by two QPDs for reflective light from MCI.
We take the error signal with modulation of the alignment and demodulation.
The values “R” of four ports of each QPD, which means whole phase rotating, is set so that I (Q) phase signal gets maximum (minimum) as below.
Modulation frequency was 12 Hz and the amplitude was 500 counts.
QPDA1 1 : 35 deg
2 : 0 deg
2 : 0 deg
QPDA1 1 : 35 deg
2 : 0 deg
Se
Secondly we report working on WFS.
3 : -25 deg
4 : 15 deg
QPDA2 1 : 15 deg
2 : -50 deg
3 : -175 deg
Secondly we report working on WFS.
4 : 50 deg
At each QPD, phase of four ports are not inverse but the same.
The ratio of power spectrum was 1.5 ~ 2 orders on 12 Hz peak.
Next, the gain of MCO coil actuators are balanced with referring oplev signal.
Peak value on 12 Hz (count/sqrt(Hz)) were as follows.
H1 H2 H3 H4
Pitch 0.136 0.144 0.143 0.156
Yaw 0.187 0.200 0.192 0.199
The gain of H2, H3 and H4 are multiplied by 0.94, 0.96 and 0.87 respectively with making H1 reference.
We also did this measurement at modulation frequency of 1 Hz and 2 Hz, but the ratio was totally different.
It is maybe because these low frequency are close to resonant frequency of mechanical modes.
Moreover, we derived sensing matrix for MCI and MCO from this modulation measurement.
The peak values of each signal are as follows.
Amplitude of modulation is shown next to the name of mirrors.
Pitch
MCO (2000 counts) MCI (5000 counts)
oplev 0.899 rad/sqrt(Hz) 0.253 rad/sqrt(Hz)
QPDA1 -269 count/sqrt(Hz) 173 count/sqrt(Hz)
QPDA2 94.6 count/sqrt(Hz) -148 count/sqrt(Hz)
Yaw
MCO (500 counts) MCI (2000 counts)
oplev 0.0965 rad/sqrt(Hz) 0.0611 rad/sqrt(Hz)
QPDA1 139 count/sqrt(Hz) 670 count/sqrt(Hz)
QPDA2 97.5 count/sqrt(Hz) 453 count/sqrt(Hz)
The sensing matrix can be calculated as below. The unit is count/rad.
Pitch
MCO MCI
A1 -299 684
A2 105 -585
Yaw
MCO MCI
A1 1440 10949
A2 1010 7414
We can diagonalize the sensing matrix for common and differential mode of MCI and MCO from this matrix.
However, the sensing gain of WFS has to be diagonalized before that.
However, the lock looks relatively short.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.
2. K1: IMC-MCL_SERVO_OFFSET
However, the lock looks relatively short.
1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.
1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.
Firstly slight works are reported.
We worked on the input mode cleaner (IMC), mainly wave front sensor (WFS).
Firstly slight works are reported.
We worked on the input mode cleaner (IMC), mainly wave front sensor (WFS).
Firstly slight works are reported.
1. Oplev calibration is turned on.
We worked on the input mode cleaner (IMC), mainly wave front sensor (WFS).
Firstly slight works are reported.
1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.
3. Alignment of IMC mirrors are adjusted toward increasing the transmitting power, which results to be 0.46 from 0.35.
At that time the values of IN_MON were as below.
Pitch Yaw
MCI -11.5 0.2
MCO 9.5 4.4
MCE 1.0 -2.9
We tried to control mirrors of IMC by oplev, but the lock is down when oplev control turns on with drift.
Secondly we report working on WFS.
The signal of alignment of IMC mirrors is taken by two QPDs for reflective light from MCI.
We take the error signal with modulation of the alignment and demodulation.
The values “R” of four ports of each QPD, which means whole phase rotating, is set so that I (Q) phase signal gets maximum (minimum) as below.
Modulation frequency was 12 Hz and the amplitude was 500 counts.
QPDA1 1 : 35 deg
2 : 0 deg
3 : -25 deg
4 : 15 deg
QPDA2 1 : 15 deg
2 : -50 deg
3 : -175 deg
4 : 50 deg
At each QPD, phase of four ports are not inverse but the same.
The ratio of power spectrum was 1.5 ~ 2 orders on 12 Hz peak.
Next, the gain of MCO coil actuators are balanced with referring oplev signal.
Peak value on 12 Hz (count/sqrt(Hz)) were as follows.
H1 H2 H3 H4
Pitch 0.136 0.144 0.143 0.156
Yaw 0.187 0.200 0.192 0.199
The gain of H2, H3 and H4 are multiplied by 0.94, 0.96 and 0.87 respectively with making H1 reference.
We also did this measurement at modulation frequency of 1 Hz and 2 Hz, but the ratio was totally different.
It is maybe because these low frequency are close to resonant frequency of mechanical modes.
Moreover, we derived sensing matrix for MCI and MCO from this modulation measurement.
The peak values of each signal are as follows.
Amplitude of modulation is shown next to the name of mirrors.
Pitch
MCO (2000 counts) MCI (5000 counts)
oplev 0.899 rad/sqrt(Hz) 0.253 rad/sqrt(Hz)
QPDA1 -269 count/sqrt(Hz) 173 count/sqrt(Hz)
QPDA2 94.6 count/sqrt(Hz) -148 count/sqrt(Hz)
Yaw
MCO (500 counts) MCI (2000 counts)
oplev 0.0965 rad/sqrt(Hz) 0.0611 rad/sqrt(Hz)
QPDA1 139 count/sqrt(Hz) 670 count/sqrt(Hz)
QPDA2 97.5 count/sqrt(Hz) 453 count/sqrt(Hz)
The sensing matrix can be calculated as below.
The unit is count/rad.
Pitch
MCO MCI
A1 -299 684
A2 105 -585
Yaw
MCO MCI
A1 1440 10949
A2 1010 7414
We can diagonalize the sensing matrix for common and differential mode of MCI and MCO from this matrix.
However, the sensing gain of WFS has to be diagonalized before that.We worked on the input mode cleaner (IMC), mainly wave front sensor (WFS).
Firstly slight works are reported.
1. Oplev calibration is turned on.
2. K1: IMC-MCL_SERVO_OFFSET is changed from -0.44 to -1.6 for keeping the lock of IMC longer.
However, the lock looks relatively short.
3. Alignment of IMC mirrors are adjusted toward increasing the transmitting power, which results to be 0.46 from 0.35.
At that time the values of IN_MON were as below.
Pitch Yaw
MCI -11.5 0.2
MCO 9.5 4.4
MCE 1.0 -2.9
We tried to control mirrors of IMC by oplev, but the lock is down when oplev control turns on with drift.
Secondly we report working on WFS.
The signal of alignment of IMC mirrors is taken by two QPDs for reflective light from MCI.
We take the error signal with modulation of the alignment and demodulation.
The values “R” of four ports of each QPD, which means whole phase rotating, is set so that I (Q) phase signal gets maximum (minimum) as below.
Modulation frequency was 12 Hz and the amplitude was 500 counts.
QPDA1 1 : 35 deg
2 : 0 deg
3 : -25 deg
4 : 15 deg
QPDA2 1 : 15 deg
2 : -50 deg
3 : -175 deg
4 : 50 deg
At each QPD, phase of four ports are not inverse but the same.
The ratio of power spectrum was 1.5 ~ 2 orders on 12 Hz peak.
Next, the gain of MCO coil actuators are balanced with referring oplev signal.
Peak value on 12 Hz (count/sqrt(Hz)) were as follows.
H1 H2 H3 H4
Pitch 0.136 0.144 0.143 0.156
Yaw 0.187 0.200 0.192 0.199
The gain of H2, H3 and H4 are multiplied by 0.94, 0.96 and 0.87 respectively with making H1 reference.
We also did this measurement at modulation frequency of 1 Hz and 2 Hz, but the ratio was totally different.
It is maybe because these low frequency are close to resonant frequency of mechanical modes.
Moreover, we derived sensing matrix for MCI and MCO from this modulation measurement.
The peak values of each signal are as follows.
Amplitude of modulation is shown next to the name of mirrors.
Pitch
MCO (2000 counts) MCI (5000 counts)
oplev 0.899 rad/sqrt(Hz) 0.253 rad/sqrt(Hz)
QPDA1 -269 count/sqrt(Hz) 173 count/sqrt(Hz)
QPDA2 94.6 count/sqrt(Hz) -148 count/sqrt(Hz)
Yaw
MCO (500 counts) MCI (2000 counts)
oplev 0.0965 rad/sqrt(Hz) 0.0611 rad/sqrt(Hz)
QPDA1 139 count/sqrt(Hz) 670 count/sqrt(Hz)
QPDA2 97.5 count/sqrt(Hz) 453 count/sqrt(Hz)
The sensing matrix can be calculated as below.
The unit is count/rad.
Pitch
MCO MCI
A1 -299 684
A2 105 -585
Yaw
MCO MCI
A1 1440 10949
A2 1010 7414
We can diagonalize the sensing matrix for common and differential mode of MCI and MCO from this matrix.
However, the sensing gain of WFS has to be diagonalized before that.
MCO MCI
A1 -299 684
A2 105 -585