advanced ligo - stanford university

Advanced LIGOthe Laser Interferometer

Gravitational-wave Observatory

The Next

Gravitational-Wave Observatory

Brian Lantz, for the LSC

(40+ institutions, hundreds of people)

SLAC Instrumentation Series, Feb 20, 2008black hole image courtesy of LISA,

http://lisa.jpl.nasa.gov



G080040

A LIGO Instrument Overview

2

This afternoon:- Introduction to Gravitational waves and their detection.- Performance of Initial LIGO (amazing, but...), plans for Enhanced LIGO, and predictions for Advanced LIGO (regular detections?).- Discussion of a few of the new instrument’s subsystems. optics, seismic isolation, laser,

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What is a Gravitational Wave?3

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A stationary electron has an electric field, andaccelerating the electron creates waves.

A stationary mass has a gravitational field, andaccelerating the mass creates waves.

But, gravitational forces are relatively weak

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What is a Gravitational Wave?

(for electron and proton)electricalforce

gravitationalforce≈ 2 · 1039

3




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1000 kg

1000 kg2 m

1 kHz

spinning a barbell in the lab is hopeless, h~10-38

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Astronomy!

• How about Neutron stars?

• Hulse and Taylor ’93.(PSR 1913+16)

• and in 300 MYears...

4

(Weisberg and Taylor)

The Swan-song

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Black Hole Collisions

courtesy of Kip Thorne, G030311, June 2003

35

Binary Black Hole MergersBlack hole collisions

5

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Binary black holes6

Centrella et. al, NASA Goddard Spaceflight center

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Supernovas and remnants7

1987a

1987aCrab Nebula, supernova in 1054,

now a spinning neutron star

HST photo courtesy of ESA

HS

T i

mage f

rom

htt

p://h

ubble

site

.org

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The LIGO concept8

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The LIGO concept9

A few interferometer tricks:- long arms, because h = dL/L- Fabry-Perot cavities in the arms- Power recycling = more power- Signal recycling = tuning to enhanced certain frequencies (new for AdLIGO, already in GEO600)

=dual-recycled Fabry-Perot Michelson Interferometer

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LIGO facilities

Livingston, LA

Hanford, WA

photos from http://www.ligo.caltech.edu

10

LIGO has 2 US sites, funded by NSF.

Part of international network, including GEO600, VIRGO, TAMA, ACIGA

http://www.ligo.caltech.edu

http://www.ligo.caltech.edu

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The LIGO vacuum equipment

drawing courtesy of Oddvar Spjeld

11

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Initial LIGO sensitivity

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Finished “S5”13

We recently completed Science run #5

1 year of triple coincidence data at design sensitivity completed on Sept 30, 2007, 2400 UTC!

Several “upper limit” papers on partial data exist.

Full data set is now being analyzed

No detections.

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image by R. Powell

Initial LIGO NS/NS range ~15 MPc (50e6 lightyears)

The Seeing14

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image by R. Powell

15

image by R. Powell

3 detector network range for NS/NS of 300 MPc

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The Advanced LIGO proposal• Proposal to the NSF to improve the sensitivity of existing

observatories to dramatically enhance the astrophysics.

• Part of an international network: GEO600 (Germany-UK), VIRGO (Italy-France), TAMA (Japan), ACIGA (Australia).

• Same facilities as Initial LIGO, but with new detectors.

• Development is very far along, carried out by many partners.

• Requested construction funding from NSF in FY2008.

• Project cost $186 M (US, 2006$)

• NSF $172 M

• AEI to supply the lasers. Already funded by Max Planck Gesellschaft for development and for $7.1M in 2006$ for fabrication.

• UK/GEO for suspensions and core opticsAlready funded by PPARC for development and for $6.87M in 2006$ for fabrication.

16

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! !

LIGO Scientific Collaboration!Australian Consortiumfor InterferometricGravitational Astronomy!The Univ. of Adelaide!Andrews University!The Australian National Univ.!The University of Birmingham!California Inst. of Technology!Cardiff University!Carleton College!Charles Sturt Univ.!Columbia University!Embry Riddle Aeronautical Univ.!Eötvös Loránd University!University of Florida!German/British Collaboration forthe Detection of Gravitational Waves!University of Glasgow!Goddard Space Flight Center!Leibniz Universität Hannover!Hobart & William Smith Colleges!Inst. of Applied Physics of the Russian Academy of Sciences!Polish Academy of Sciences!India Inter-University Centrefor Astronomy and Astrophysics!Louisiana State University!Louisiana Tech University!Loyola University New Orleans!University of Maryland!Max Planck Institute for Gravitational Physics

!University of Michigan!University of Minnesota!The University of Mississippi!Massachusetts Inst. of Technology!Monash University!Montana State University!Moscow State University!National Astronomical Observatory of Japan!Northwestern University!University of Oregon!Pennsylvania State University!Rochester Inst. of Technology!Rutherford Appleton Lab!University of Rochester!San Jose State University!Univ. of Sannio at Benevento, and Univ. of Salerno!University of Sheffield!University of Southampton!Southeastern Louisiana Univ.!Southern Univ. and A&M College!Stanford University!University of Strathclyde!Syracuse University!Univ. of Texas at Austin!Univ. of Texas at Brownsville!Trinity University!Universitat de les Illes Balears!Univ. of Massachusetts Amherst!University of Western Australia!Univ. of Wisconsin-Milwaukee!Washington State University!University of Washington

G080040

The Advanced LIGO proposal

• Milestones:

• Advanced LIGO funding start in FY2008; fabrication, assembly, and stand-alone testing of detector components

• Advanced LIGO starts decommissioning initial LIGO instruments in early 2011, installing new detector components from stockpile.

• First Advanced LIGO interferometer accepted in early 2013, second and third in mid-2014. Construction project completes!

• Commissioning of instruments, Engineering runs starting in 2014, Science in 2015.

18

Enhanced LIGO upgrade

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Advanced LIGO Preparation

• We are currently installing a “modest” set of upgrades funded with Initial LIGO resources.

• Make the best use the time before 2011.

• Gain experience with Advanced LIGO technology- Take laser from 10 W to 30 W, - Install the new DC readout scheme,- Install 1 new style seismic isolation system,- Try the new computing/ control infrastructure.

• Make a factor of 2 improvement in the sensitivity. (about 6-7 times more galaxies in range).

19

Enhanced LIGO upgrade

Enhanced LIGO

G080040

Courtesy of Kip Thorne

SourcesNeutron star and Black hole binaries inspiral merger

Spinning NS’s LMXB known pulsars unknown?

Birth of NS (supernovas) tumbling convection

Stochastic Background remnants of the big bang

20

NS/NS Inspiral 300Mpc; NS/BH Inspiral 650Mpc

BH/BH Inspiral, z=0.4

10 20 50 100 200 500 1000

10- 24

10- 23

10- 22

Initial L

IGO

NB Adv LIGO

WB Adv LIGO

10 Mo/10M

o BH/BH inspiral 100Mpc

50Mo/50M

oBH/BH Merger, z=2

20Mo/20MoBH/BH Merger, z=1

Ω=10 -9

Ω=10 -11

Ω=10 -7

Sco X-1

LMXBs

Kno

wn

Pul

sar

ε=10

-6 , r=1

0kpc

ε=10

-7r=

10kp

c

frequency, Hz

BH/BH Inspiral 400Mpc

Merger

Merger

h(f

)a

nd

h s(f

) /H

z1/2

Crab SpindownUpper Limit

Vela SpindownUpper Limit

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Advanced LIGO - Technology21



10 20 50 100 200 500 1000

10- 24

10- 23

10- 22

Initial L

IGO

NB Adv LIGO

WB Adv LIGO

10 Mo/10M


50Mo/50M

oBH/BH Merger, z=2


Ω=10 -9

Ω=10 -11

Ω=10 -7

Sco X-1

LMXBs

Kno

wn

Pul

sar

ε=10

-6 , r=1

0kpc

ε=10

-7r=

10kp

c

frequency, Hz


Merger

Merger

h(f

)a

nd

h s(f

) /H

z1/2



Technical Improvements

G080040




10 20 50 100 200 500 1000

10- 24

10- 23

10- 22

Initial L

IGO

NB Adv LIGO

WB Adv LIGO

10 Mo/10M


50Mo/50M

oBH/BH Merger, z=2


Ω=10 -9

Ω=10 -11

Ω=10 -7

Sco X-1

LMXBs

Kno

wn

Pul

sar

ε=10

-6 , r=1

0kpc

ε=10

-7r=

10kp

c

frequency, Hz


Merger

Merger

h(f

)a

nd

h s(f

) /H

z1/2



Environmental Isolation: platforms & pendulums


G080040




10 20 50 100 200 500 1000

10- 24

10- 23

10- 22

Initial L

IGO

NB Adv LIGO

WB Adv LIGO

10 Mo/10M


50Mo/50M

oBH/BH Merger, z=2


Ω=10 -9

Ω=10 -11

Ω=10 -7

Sco X-1

LMXBs

Kno

wn

Pul

sar

ε=10

-6 , r=1

0kpc

ε=10

-7r=

10kp

c

frequency, Hz


Merger

Merger

h(f

)a

nd

h s(f

) /H

z1/2




Thermal Noise control:suspensions & coatings


G080040




10 20 50 100 200 500 1000

10- 24

10- 23

10- 22

Initial L

IGO

NB Adv LIGO

WB Adv LIGO

10 Mo/10M


50Mo/50M

oBH/BH Merger, z=2


Ω=10 -9

Ω=10 -11

Ω=10 -7

Sco X-1

LMXBs

Kno

wn

Pul

sar

ε=10

-6 , r=1

0kpc

ε=10

-7r=

10kp

c

frequency, Hz


Merger

Merger

h(f

)a

nd

h s(f

) /H

z1/2





More Powernew 180 W laser830 kW circulating in arms


G080040




10 20 50 100 200 500 1000

10- 24

10- 23

10- 22

Initial L

IGO

NB Adv LIGO

WB Adv LIGO

10 Mo/10M


50Mo/50M

oBH/BH Merger, z=2


Ω=10 -9

Ω=10 -11

Ω=10 -7

Sco X-1

LMXBs

Kno

wn

Pul

sar

ε=10

-6 , r=1

0kpc

ε=10

-7r=

10kp

c

frequency, Hz


Merger

Merger

h(f

)a

nd

h s(f

) /H

z1/2





More Powernew 180 W laser830 kW circulating in arms


Signal recycling gives tunable response

G080040

Reflections of the Technologyin a piece of glass

22

4km arm cavity

4km arm cavity

corner

en

d s

tati

on

en

d s

tati

on


Optic motion should be limitedby “fundamental” processes - - goal of 10-19 m/!Hz at 10 Hz

G080040

!"!#$%&'()&*+,$!&-*,.-/0.$10)$2345634

7 8')'9,:,)-$10)$-&-*,.-/0.

7 3,-:$'.($*,.&+:/9':,$9'--,-$#$,';<$=>$?@A$B=$;9$C(/'9D$E$F>$;9A$-/+/;'

7 G:<,)$9'--,-#$FF$?@A$FF$?@

7 H/.'+$-:'@,#$I>$;9$-/+/;'$)/JJ0.-A$$$$$$KLK$99$E$>LKK$99A$$$$$$$$$$$$$$$$$$$$$M,):/;'+$J0&.;,$90(,#$NLN$OP$$$$$$$$$$1/)-:$Q/0+/.$90(,#$R=S>$OP

7 GQ,)'++$+,.@:<$C-&-*,.-/0.$*0/.:$:0$0*:/;$;,.:),D$KLIB$9

7 4T3UTV$90(,+$&-,($:0$;09*&:,$:)'.-1,)$1&.;:/0.-$C&*(':,$1)09$4$V'):0.$.0:$W,:$/9*+,9,.:,($X+0.@/:&(/.'+$3H$Y/++$J,$&.'11,;:,(A$Q,):/;'+$3H$Y/++$J,$-+/@<:+W$CZK>[D$+')@,)$:<'.$-<0Y.$0Q,)+,'1D

7 !"!$),\&/),9,.:-$:'?,.$1)09$!"!$]^]$(0;&9,.:$3>K>>>_X>F

8/;:&),$/.$<,),

`30))/, '.($4$8XU+0W(


22

4km arm cavity

4km arm cavity

corner

en

d s

tati

on

en

d s

tati

on



G080040

!"!#$%&'()&*+,$!&-*,.-/0.$10)$2345634

7 8')'9,:,)-$10)$-&-*,.-/0.

7 3,-:$'.($*,.&+:/9':,$9'--,-$#$,';<$=>$?@A$B=$;9$C(/'9D$E$F>$;9A$-/+/;'

7 G:<,)$9'--,-#$FF$?@A$FF$?@


7 GQ,)'++$+,.@:<$C-&-*,.-/0.$*0/.:$:0$0*:/;$;,.:),D$KLIB$9


7 !"!$),\&/),9,.:-$:'?,.$1)09$!"!$]^]$(0;&9,.:$3>K>>>_X>F

8/;:&),$/.$<,),

`30))/, '.($4$8XU+0W(


22

4km arm cavity

4km arm cavity

corner

en

d s

tati

on

en

d s

tati

on


Below 10 Hz: Seismic Isolation


G080040

!"!#$%&'()&*+,$!&-*,.-/0.$10)$2345634

7 8')'9,:,)-$10)$-&-*,.-/0.

7 3,-:$'.($*,.&+:/9':,$9'--,-$#$,';<$=>$?@A$B=$;9$C(/'9D$E$F>$;9A$-/+/;'

7 G:<,)$9'--,-#$FF$?@A$FF$?@


7 GQ,)'++$+,.@:<$C-&-*,.-/0.$*0/.:$:0$0*:/;$;,.:),D$KLIB$9


7 !"!$),\&/),9,.:-$:'?,.$1)09$!"!$]^]$(0;&9,.:$3>K>>>_X>F

8/;:&),$/.$<,),

`30))/, '.($4$8XU+0W(


22

4km arm cavity

4km arm cavity

corner

en

d s

tati

on

en

d s

tati

on




50 - 200 Hz: Coating Noise

G080040

!"!#$%&'()&*+,$!&-*,.-/0.$10)$2345634

7 8')'9,:,)-$10)$-&-*,.-/0.

7 3,-:$'.($*,.&+:/9':,$9'--,-$#$,';<$=>$?@A$B=$;9$C(/'9D$E$F>$;9A$-/+/;'

7 G:<,)$9'--,-#$FF$?@A$FF$?@


7 GQ,)'++$+,.@:<$C-&-*,.-/0.$*0/.:$:0$0*:/;$;,.:),D$KLIB$9


7 !"!$),\&/),9,.:-$:'?,.$1)09$!"!$]^]$(0;&9,.:$3>K>>>_X>F

8/;:&),$/.$<,),

`30))/, '.($4$8XU+0W(


22

4km arm cavity

4km arm cavity

corner

en

d s

tati

on

en

d s

tati

on




50 - 200 Hz: Coating Noise

Above 200 Hz: Shot Noise

G080040 23

Seismic Isolation & Alignment

Isolation of the test mass10 Hz motion test mass 1x10-19 m/!Hz ground ~4x10-10 m/!Hz

rms length variation <1x10-14 m

7 layers of isolation

G080040 23


1x10-19 m/!Hz near 10 Hz4 stage pendulum




G080040 23






2 stage active isolation table

3x10-12 m/!Hz at 10 Hz

G080040 23






2 stage active isolation table

1 stage Hydraulic External Pre-Isolator

~4x10-10 m/!Hz at 10 Hz

G080040 24

> Range of +/- 1 mm> Easily holds 1e3 N (400 lbs) static offset> Quiet (<1 nm/!Hz at 1 Hz)

Seismic Isolation & Alignment - HEPI

G080040 24

> Range of +/- 1 mm> Easily holds 1e3 N (400 lbs) static offset> Quiet (<1 nm/!Hz at 1 Hz)> 1 Vert, 1 Horz per pier for full 6DOF control> springs carry static load> Feed-forward ground sensors and feed-back local sensors for alignment and isolation.> Installed and running at LLO.


G080040

X-arm length disturbance, noisy afternoon

Frequency (Hz)10

-210

-11 10

10-10

10-9

10-8

10-7

10-6

10-5

HEPI on, sensor correction on

", rmsHEPI off

", rms

Vel

oci

ty A

SD

(m

/s/H

z1/2

) or

rms

(m/s

)

rms - HEPI off

rms - HEPI on

rms - lock threshold

25


Run time in S4 increased to 74.5%, from 21.8%

G080040

26

Seismic Isolation & Alignment - platform

• Technology demonstrator designed and installed in Stanford vacuum system (ETF).

! mechanical system designed for approximately LIGO size platform, with approx half-size payload capacity.

! most sensors and actuators as final design.

• True prototype being installed at MIT for full scale, UHV, tests with suspension systems.

! modal frequencies designed to be > 150 Hz to accommodate " 50 Hz servo unity-gain point.

! modeling of 6 x 6 DOF stiffness at low frequencies. We design horizontal-tilt cross coupling < 1/500 rad/m.

! new design for rigid and strong stops, to exactly position stages and restrict motion during earthquakes.

! can accommodate " 800 kg payload. Servo and mechanical design need to tolerate mechanically reactive massive payload

G080040

Ground X

Stage 1 X

Stage 2 X

goal

27


•Isolation requirement: 100 at 1 Hz (met!)3000 at 10 Hz (design mod)

•We modified the LASTI prototype to increase vertical passive isolation at 10 Hz, based on these tests.

G080040

Ground X

Stage 1 X

Stage 2 X

goal

27


•Isolation requirement: 100 at 1 Hz (met!)3000 at 10 Hz (design mod)

•We modified the LASTI prototype to increase vertical passive isolation at 10 Hz, based on these tests.

•LASTI prototype now being tested at MIT.

G080040

Single stage isolatorfor auxiliary optics

28

• Bolted aluminum structure Suspended by 3 blade springs & “wires”• isolation of 50-100 above 1 Hz

• designed for “auxiliary” optics - input and output mode cleaners, - power and signal recycling mirrors, - beam expanding telescope,- GW signal readout bench • to be installed into Enhanced LIGO

G080040

Single stage isolatorfor auxiliary optics

28

• Bolted aluminum structure Suspended by 3 blade springs & “wires”• isolation of 50-100 above 1 Hz

• designed for “auxiliary” optics - input and output mode cleaners, - power and signal recycling mirrors, - beam expanding telescope,- GW signal readout bench • to be installed into Enhanced LIGO next week

G080040 29

Multiple-pendulums for control flexibility & seismic attenuation

Each stage gives ~1/f2 isolation above the natural frequency. More that 1e6 at 10 Hz.

Test masses: Synthetic fused silica, 40 kg, 34 cm dia. » Q # 1e7 » low optical absorption

Final suspensions are fused silica,joined to form monolithic final stages.

Thermal vibrations at the optical surface set the performance limit of the suspension.

!"!#$%&'()&*+,$!&-*,.-/0.$10)$2345634

7 8')'9,:,)-$10)$-&-*,.-/0.

7 3,-:$'.($*,.&+:/9':,$9'--,-$#$,';<$=>$?@A$B=$;9$C(/'9D$E$F>$;9A$-/+/;'

7 G:<,)$9'--,-#$FF$?@A$FF$?@


7 GQ,)'++$+,.@:<$C-&-*,.-/0.$*0/.:$:0$0*:/;$;,.:),D$KLIB$9


7 !"!$),\&/),9,.:-$:'?,.$1)09$!"!$]^]$(0;&9,.:$3>K>>>_X>F

8/;:&),$/.$<,),

`30))/, '.($4$8XU+0W(

(Bas

ed o

n G

EO

600 d

esig

n)

Drawings courtesy of Calum Torrie and GEO600

Pendulum SuspensionSuspensions material from N. Robertson, GEO600, and the SUS team

G080040 30!"!#$%&'()&*+,$!&-*,.-/0.$10)$2345634

7 8')'9,:,)-$10)$-&-*,.-/0.

7 3,-:$'.($*,.&+:/9':,$9'--,-$#$,';<$=>$?@A$B=$;9$C(/'9D$E$F>$;9A$-/+/;'

7 G:<,)$9'--,-#$FF$?@A$FF$?@


7 GQ,)'++$+,.@:<$C-&-*,.-/0.$*0/.:$:0$0*:/;$;,.:),D$KLIB$9


7 !"!$),\&/),9,.:-$:'?,.$1)09$!"!$]^]$(0;&9,.:$3>K>>>_X>F

8/;:&),$/.$<,),

`30))/, '.($4$8XU+0W(

(Bas

ed o

n G

EO

600 d

esig

n)

Drawings courtesy of Calum Torrie and GEO600

Pendulum Suspension

silicate bonding creates a monolithic final stage

Multiple-pendulums for control flexibility & seismic attenuation

Each stage gives ~1/f2 isolation above the natural frequency. More that 1e6 at 10 Hz.

G080040 31

Quadruple pendulum now installed at MIT with “metal mirrors”.

Interaction tests between pendulum and platform have begun

Pendulum Suspension

Ribbon pulling machine at the University of Glasgow

G080040

Mass 40 kg, fused silica

Dimensions 340 mm x 200 mm

Surface figure < 1 nm rms

Micro-roughness < 0.1 nm rms

Double-pass optical homogeneity < 20 nm rms,

Bulk absorption (Heraeus Suprasil 311) < 3 ppm/cm

Bulk mechanical loss < 3x10-9

Optical coating: Titania doped Tantala/ silica

Optical coating absorption < 0.5 ppm(required) < 0.2 ppm(goal)

Optical coating mechanical loss < 2x10-4 (required) < 3x10-5 (goal)

Optical coating scatter < 2 ppm(required) < 1 ppm(goal)

Arm cavity optical loss / round trip < 75 ppm

Test Mass Requirements32

courtesy of G. Harry, S. Rowan, and the optics working group

G080040















good enough for Thermal Comp. System

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good enough for Thermal Comp. System

samples at 0.4 ppm

measured 8.5x10-5

not yet...

G080040 33

Motion of the Test Mass with Proposed Mods to ASI design

freq (Hz)

equiv

ale

nt sin

gle

mass m

otion, (m

/rtH

z)

cre

ate

d b

y s

ho

w_

pe

rf o

n 0

3!

Au

g!

20

05

courtesy of Brian Lantz

cre

ate

d b

y s

ho

w_

pe

rf o

n 0

3!

Au

g!

20

05

courtesy of Brian Lantz

6 7 8 9 10 11 12 13 14 1510

!21

10!20

10!19

10!18

10!17 95% noise (max)

50% noise (max)95% noise ! worst case50% noise ! worst caselong. motion from SEI totallong. motion from SEI Zlong. motion from SEI Xlong. from SUS Thermal

Predicted motion of the Advanced LIGO Test Mass

1e-19 m/!Hz

thermal

seismic

NewtonianBackground

Pendulum Suspension

G080040

Power, Optics, and Interferometers

34

G080040

Power, Optics, and Interferometers

34

180 W laser

G080040

High Power Laser

35

•180 W with good beam shape

•1064 nm (YAG)

•very low intensity and frequency noise

•Developed by AEI(Max-Planck Institute, Hanover) & Laser Zentrum Hanover (LZH)

•stable front end determines laser frequency andfrequency fluctuations.(NPRO & 4 rod Nd:YVO)

•high power stage, Injection seeded ring oscillatordetermines power, power fluctuations, and beam shape.

30 w

att

seed

las

er

high-power injection-locked oscillator

Laser material from B. Wilke, P. Wessels, GEO600, AEI, LZH

G080040

High Power Laser

36

•180.5 W output power (91.5% in TEM00)

• good spatial profile

• power fluctuations close to requirement.

• 37 W “seed” laser installed at one and about to be installed at second site for Enhanced LIGO.

Still to Verify:• RIN at low frequency

• preparing to build Engineering Prototype

Power fluctuationsBeam profile of high power beam

G080040

14LIGO-G060226-00-M

Interferometer performance estimate

101

102

103

10-24

10-23

10-22

Frequency (Hz)

Str

ain

no

ise (

Hz

-1/2

)

mirror thermal

quantum

suspension thermal

residual gas

newtonian

background

seismic

total

Tuning37

Instrument noise floor set bythermal noise (coatings) &unified quantum noise (above 10 Hz)

G080040

Tuning38

moving bumppick your favorite source!

15LIGO-G060226-00-M

101

102

103

10-24

10-23

10-22

Frequency (Hz)

Str

ain

no

ise (

Hz

-1/2

)

Interferometer performance estimate

mirror thermal

quantum

suspension thermal

residual gas

newtonian

background

seismic

total

tuned for

higher

frequencies

lower power &

tuned for low

frequencies

fake curves for tightly tuned pulsar searches

Signal recycling mirror makes it possibleto tune the response to your favorite source.

When we start measuring gravitational waves, this flexible instrument can be directed towards many different astrophysical goals.

G080040

and more...39

• End-to-end model

• Sensing and control for all length and angle DOFs

• Big computing pipeline for both instrument control and for data analysis.

• output mode cleaner (CIT 40 meter lab)

• high power input optics (Univ. Florida)

• 40 m lab & Thermal noise interferometer at Caltech, LASTI at MIT, high-power test facility at Gingin, 10 meter lab at Univ. Glasgow, ETF at Stanford, the LIGO and GEO observatories...

G080040

in Conclusion...40

• LIGO science collaboration is large and active,

• We’ve developed a tremendous amount of new technology,

• We now have the technology in hand to make a fantastic new instrument, and

• We are ready to start the construction.

The astrophysics will be great!

G080040

Data Rate41

Advanced LIGO Initial LIGO

channel cnt.(LHO, LLO, total)

5464+3092 =8556

1224 + 714 =1938

Acquisition rate29.7 + 16.3 =

46 MB/s11.3 + 6.1 =17.4 MB/s

Recorded rate12.9 + 7.7 =20.6 MB/s

6.3 + 3.5 =9.9 MB/s

advanced ligo - stanford university

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