Interferometer Parameters
Old parameter sets (before 2010)
(Classical-noise parameters are here)
Parameter |
LCGT VRSE-D1 |
LCGT VRSE-B |
units |
Laser source |
|||
Wave length |
1064 |
|
nm |
Initial Laser Power |
150 |
|
W |
Injecting Laser Power into IFO |
78.48 (in total), 75 (carrier) |
|
W |
Modulation depth |
0.3 for both |
|
|
RF freq 1 |
11.25M (PM) |
|
Hz |
RF freq 2 |
45.00M (PM) |
|
Hz |
MC1 length |
13.324109 |
|
m |
MC2 length |
|
|
m |
MC1 Finesse |
|
|
|
MC2 Finesse |
|
|
|
Parameters of interferometer |
|||
Arm cavity Finesse |
1550 |
|
|
Arm power gain |
|
|
|
Arm power (single arm)2 |
420.5 |
|
kW |
Arm cavity cut-off frequency |
|
|
Hz |
PR gain |
11 |
|
|
PRC power on BS |
|
|
W |
PR cavity cut-off frequency |
|
|
Hz |
PR-Arm cut-off frequency |
|
|
Hz |
SR gain |
11 |
|
|
Signal band |
|
|
Hz |
MICH contrast |
|
|
|
Other losses in PRC |
|
|
|
Other losses in SRC |
|
|
|
Cavity Length |
|||
Arm cavity length |
3006.69 |
|
m |
PR cavity length |
73.2826 |
|
m |
Asymmetry length |
3.33103 |
|
m |
BS-FM length |
25 |
|
m |
SR cavity length |
73.2826 |
|
m |
SRC detuning phase |
86.5 |
90.0 |
degree |
Mirror geometries |
|||
EM mass |
30 |
|
kg |
FM mass |
30 |
|
kg |
PRM mass |
|
|
kg |
SRM mass |
|
|
kg |
BS mass |
|
|
kg |
|
|
|
|
EM ROC |
7113.900 |
|
m |
FM ROC |
7113.900 |
|
m |
FM AR ROC |
|
|
m |
PRM ROC |
|
|
m |
SRM ROC |
|
|
m |
BS ROC |
Infinity |
|
m |
|
|
|
|
EM radius/thickness |
25 / 15 |
|
cm |
FM radius/thickness |
25 / 15 |
|
cm |
PRM radius/thickness |
|
|
cm |
SRM radius/thickness |
|
|
cm |
BS radius/thickness |
|
|
cm |
Mirror optical properties |
|||
EM Reflectivity |
0.999945 |
|
|
FM Reflectivity |
0.996 |
|
|
PRM Reflectivity |
0.9 |
|
|
SRM Reflectivity |
0.8464 = 0.922 |
|
|
BS Reflectivity |
0.5 |
|
|
HR Coating Loss of EM, FM, PRM and SRM |
45e-6 |
|
|
BS Loss |
100e-6 |
|
|
Transmissivity |
1 - R - Loss |
|
|
AR Transmissivity |
0.999 |
|
|
AR Coating Loss |
|
|
|
|
|
|
|
Bulk loss (absorption) (large optics ??? for Sapphire: ???FM, EM) |
|
|
ppm |
Bulk loss (absorption) (small optics ??? for Fused Silica: ???) |
|
|
ppm |
|
|
|
|
Output Mode Cleaner |
|||
OMC length |
1.5 |
|
m |
OMC Finesse |
2000 |
|
|
OMC input/output mirror reflectivity |
|
|
|
OMC end mirror reflectivity |
|
|
|
OMC MC FSR |
??? |
|
MHz |
DC readout phase |
134.7 |
121.8 |
degree |
Control Bandwidth |
|||
Quantum efficiency |
0.9 |
|
|
CARM control band width |
30k |
|
Hz |
DARM control band width |
200 |
|
Hz |
PRC control band width |
50 |
|
Hz |
MICH control band width |
50 |
|
Hz |
SRC control band width |
50 |
|
Hz |
Feed-Forward gain |
-0.97 (openloop), 1/(1-0.97) = 30 (closed loop) |
|
|
To do list to define parameters for 2009
Reference
Arm power was defined by sum of both arm powers. It should be a stored power of single arm. (2)