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 (AM)

Hz

Primary parameters of interferometer

Arm cavity Finesse

1546

Arm cavity power gain

960

PR gain

10.4

Arm power (single arm)²

374k = 75 * 10.4 * 960 /2

W

PRC power on BS

780 = 75 * 10.4

W

Cavity Length

Arm cavity length

3000

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 optical properties

EM Reflectivity

0.999945

FM Reflectivity

0.996000

PRM Reflectivity

0.900000

SRM Reflectivity

0.846400 = 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

1000e-6

Bulk loss (absorption) (large optics ??? for Sapphire: ???FM, EM)

20

ppm

Bulk loss (absorption) (small optics ??? for Fused Silica: ???)

2.5

ppm

Arm cavity cut-off frequency

Hz

PR cavity cut-off frequency

Hz

PR-Arm cut-off frequency

Hz

SR gain

24

Signal band

Hz

MICH contrast

Other losses in PRC

Other losses in SRC

Mirror geometries

EM mass

30

kg

FM mass

30

kg

PRM mass

TBD

kg

SRM mass

TBD

kg

BS mass

TBD

kg

EM ROC

1900

m

FM ROC

1900

m

FM AR ROC

Flat

m

PRM ROC

TBD

m

SRM ROC

TBD

m

BS ROC

Infinity

m

EM radius/thickness

25 / 15

cm

FM radius/thickness

25 / 15

cm

PRM radius/thickness

TBD

cm

SRM radius/thickness

TBD

cm

BS radius/thickness

TBD

cm

Mode Cleaner

MC1 length

10.0

m

MC2 length

13.324109

m

MC1 Finesse

TBD

MC2 Finesse

TBD

Output Mode Cleaner

OMC length

1.5

m

OMC Finesse

2000

OMC input/output mirror reflectivity

TBD

OMC end mirror reflectivity

TBD

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)