Optical Parameters

Parameter

iLCGT

mLCGT

units

Laser source

Wave length

1064

1064

nm

Initial Laser Power

10-20

20

W

Injecting Laser Power into IFO

10-20

20

W

Modulation depth

--

--

RF freq 1

TBD (PM)

11.25 (PM)

MHz

RF freq 2

NA

45 (AM)

MHz

Primary parameters of interferometer

Arm cavity Finesse

1546

1546

Arm cavity power gain

960

960

PR gain

No PR

~10

PRC power on BS

10-20

200

W

Cavity Length

Arm cavity length

3000

3000

m

PR cavity length

No PR

73.2826

m

Asymmetry length

3.33103

3.33103

m

BS-FM length

25

25

m

SR cavity length

No SR

73.2826

m

SRC detuning phase

No SR

86.0

degree

Mirror optical properties

EM Reflectivity

0.999945?

0.999945?

FM Reflectivity

0.996000

0.996000

PRM Reflectivity

No PR

0.77

SRM Reflectivity

No SR

0.85

BS Reflectivity

0.5

0.5

HR Coating Loss of EM and FM

45e-6?

45e-6?

BS Loss

--

--

AR Transmittance

--

--

AR Coating Loss

--

--

MICH contrast

Other losses in PRC

Other losses in SRC

Mirror geometries

EM mass

10.8

10.8

kg

FM mass

10.8

10.8

kg

PRM mass

No PR

10.8

kg

SRM mass

No SR

10.8

kg

BS mass

29.9

29.9

kg

EM ROC

7260 or 7320

7260 or 7320

m

FM ROC

7260 or 7320

7260 or 7320

m

FM AR ROC

Inf

Inf

m

PRM ROC

No PR

TBD

m

SRM ROC

No SR

TBD

m

BS ROC

Inf

Inf

m

EM diameter/thickness

25 / 10

25 / 10

cm

FM diameter/thickness

25 / 10

25 / 10

cm

PRM diameter/thickness

No PR

25 / 10

cm

SRM diameter/thickness

No SR

25 / 10

cm

BS diameter/thickness

38 / 12

38 / 12

cm

Mode Cleaner

MC1 length

--

--

m

MC2 length

26.648218

26.648218

m

MC1 Finesse

--

--

MC2 Finesse

--

--

Output Mode Cleaner

OMC length

No OMC

TBD

m

OMC Finesse

No OMC

TBD

OMC input/output mirror reflectivity

No OMC

TBD

OMC end mirror reflectivity

No OMC

TBD

OMC MC FSR

No OMC

TBD

MHz

DC readout phase

NA

113.4 (BRSE) / 125.8 (DRSE)

degree

Control Bandwidth

Quantum efficiency

0.9

0.9

 

CARM control band width

30k?

--

Hz

DARM control band width

200?

--

Hz

PRC control band width

No PR

--

Hz

MICH control band width

50?

--

Hz

SRC control band width

No SR

--

Hz

Feed-Forward gain

TBD

--