Download Advanced LIGO—the Next Generation

Advanced LIGO
The Next Generation
Philip Lindquist, Caltech
XXXVIII Moriond Conference
Gravitational Waves and Experimental Gravity
March 23, 2003
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The LIGO Mission
To develop the field

LIGO infrastructure is in place
» Designed to support the evolving field of gravitational wave
science
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The LIGO Mission
To develop the field

LIGO infrastructure is in place
» Designed to support the evolving field of gravitational wave
science

Initial LIGO is in operation
» Sensitivity is improving steadily, approaching goal
» Observations are yielding first astrophysical results
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Livingston 4km Sensitivity History
May 01
Jan 03
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The LIGO Mission
To develop the field

LIGO infrastructure is in place
» Designed to support the evolving field of gravitational wave
science

Initial LIGO is in operation
» Sensitivity is improving steadily, approaching goal
» Observations are yielding first astrophysical results


One year of integrated observation time is planned
Detection is plausible with the initial LIGO
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The LIGO Mission
To develop the field

LIGO infrastructure is in place
» Designed to support the evolving field of gravitational wave
science

Initial LIGO is in operation
» Sensitivity is improving steadily, approaching goal
» Observations are yielding first astrophysical results



One year of integrated observation time is planned
Detection is plausible with the initial LIGO
With or without detection, astrophysical community will
want/demand more sensitive detectors
Advanced LIGO
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Advanced LIGO Reach

Next Detector
» Must be relevant for
astrophysics
» Should approach limits of
reasonable extrapolations for
detector physics and
technologies
» Should lead to realizable,
practical, reliable instrument
» Should exist neither too early
nor too late
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Advanced LIGO Reach

Next Detector
» Must be relevant for
astrophysics
» Should approach limits of
reasonable extrapolations for
detector physics and
technologies
» Should lead to realizable,
practical, reliable instrument
» Should exist neither too early
nor too late

Advanced LIGO
» >10 X sensitivity, ~ 3000 in
rate (population density
dependent)
» ~2.5 hours = 1 year of
initial LIGO
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Astrophysical Reach




Neutron Star
and Black Hole
Binaries
Spinning
Neutron Stars
NS Birth (Super
Novae, AIC)
Stochastic
Background
(Chart by Kip Thorne)
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Projected Advanced LIGO Performance


Suspension thermal noise
Optical noise
Int. thermal
Susp. thermal
Total noise
Internal thermal noise
Initial LIGO
-22
10-2210
Newtonian background,
estimate for LIGO sites
h(f) / Hz1/2

10-2310

Seismic “cutoff” at 10 Hz
-23
h(f), Hz-1/2
10-2410
-24

Unified quantum noise
dominates at
most frequencies for full- 10-25
10
power, broadband tuning
10
1 Hz
-25
0
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10 Hz
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10
10
f / Hz
100 Hz
3
10
1 KHz
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Advanced LIGO Basic Configuration
Current LIGO
Power recycled
Fabry-Perot to
increase storage time
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Advanced LIGO Basic Configuration
Current LIGO
Power recycled
Fabry-Perot to
increase storage time
Advanced LIGO
Increased Power
Heavier Test Masses
Quad Suspensions
Improved Isolation
Signal Recycling
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Signal Recycling
Can focus sensitivity
where needed
» Sub-wavelength
adjustments of
resonance in signal
recycling cavity

Allows optimization
» Technical constraints
» Astrophysical
signatures
-21
10
-22
10
h(f) /Hz1/2

-23
10
Su
bst
-24
10
rat
et
he
rm
al n
ois
e
-25
10
1
10
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3
10
10
Frequency (Hz)
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Limits to Sensitivity--Thermal Noise
Thermal motion is
proportional to
Lmechanical
Low-loss materials
and techniques
needed

» Test masses:
crystalline sapphire,
40 kg, 32 cm diameter
» Suspensions: fused
silica
» Monolithic final stages
» Multiple pendulums
for control and
seismic attenuation
(GEO 600)
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Optical coating also source
of mechanical loss,
development underway
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Limits to Sensitivity--External Forces

Coupling of seismic noise
through isolation system
suppressed using active
servo controls, passive
“pendulum” isolation
» Two 6-degree-of-freedom
platforms stabilized from
0.03 to 30 Hz
» Net suppression of motion
in gravitational-wave band
is 13 orders of magnitude
or more
» Suppression of motion
below the band also critical
to hold sensing system
(control) in linear domain,
avoid up-conversion
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Low-Frequency Limit

Newtonian background is limit for ground-based
detectors (~10 Hz)
» Time-varying distribution of mass in vicinity of test mass
» Seismic compression, rarefaction of earth dominates
» Advanced LIGO targeted to reach this limit for our sites

For GW astrophysics below 10 Hz, space-based
instruments needed  LISA
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Advanced LIGO Proposal

Submitted February 2003 (NSF PHY-0328418)
Prepared a “bottoms up” cost estimate
(approximately 5000 detailed line items)
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Advanced LIGO Proposal


Submitted February 2003 (NSF PHY-0328418)
Prepared a “bottoms up” cost estimate
(approximately 5000 detailed line items)
Total Cost Estimate: $240,000,000
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Advanced LIGO Proposal



Submitted February 2003 (NSF PHY-0328418)
Prepared a “bottoms up” cost estimate
(approximately 5000 detailed line items)
Total Cost Estimate: $240,000,000
Proposed LIGO Cost $122,000,000 (fabrication plus
some salaries for installation, specialty engineering,
added outreach)
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Advanced LIGO Proposal




Submitted February 2003 (NSF PHY-0328418)
Prepared a “bottoms up” cost estimate
(approximately 5000 detailed line items)
Total Cost Estimate: $240,000,000
Proposed LIGO Cost $122,000,000 (fabrication plus
some salaries for installation, specialty engineering,
added outreach)
$25.5 million provided by collaborators
» GEO (Hanover, Birmingham, Rutherford, Glasgow)
» ACIGA
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Advanced LIGO Timeline

Initial LIGO Observation 2002 – 2006
» 1+ year observation within LIGO Observatory
» Significant networked observation with GEO, LIGO, TAMA

Structured R&D program to develop technologies 1998 2005
» Conceptual design developed by LSC in 1998
» Current Cooperative Agreement carries R&D to Final Design, 2005


Proposal submitted in Feb 2003 for fabrication,
installation
Long-lead purchases planned for 2004
» Sapphire Test Mass material, seismic isolation fabrication
» Prepare a ‘stock’ of equipment for minimum downtime, rapid installation

Start installation in 2007
» Baseline is a staged installation, Livingston followed by Hanford Observatories

Start coincident observations in 2009
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Proposed Funding Profile



Long lead procurements begin in 2004
Procurements peak in 2006
Installation begins in 2007
70.00
$ Millions
60.00
Escalation
50.00
Fabrication
40.00
Fab Labor
30.00
Development
20.00
10.00
-
00 001 002 003 004 005 006 007 008 009 010
0
2
2
2
2
2
2
2
2
2
2
2
Fiscal Year
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The Advanced LIGO Community



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Scientific impetus, expertise, and development provided by LIGO
Scientific Collaboration (LSC)
» Synergy, critical mass (400+ individuals, 100+ graduate
students, 40+ institutions)
» International support and significant material participation
» Especially strong collaboration with German-UK GEO group,
capital partnership
Advanced LIGO design, R&D, and fabrication shared with
participants
» LIGO laboratory leads, coordinates, is responsible for
observatories
Continuing support from NSF at all levels
International network growing: VIRGO, GEO-600, TAMA, ACIGA
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Advanced LIGO Status Summary

Initial LIGO is in operation
»
»
»
»

We are preparing publications from first science run
Second science run underway
Third science run at target sensitivity scheduled to begin next year
Discovery plausible
Advanced LIGO on the horizon
» Advanced R&D and baseline design proceeding
» Strong international partnership—GEO, ACIGA
» Plan supports start of installation in 2007
Gravitational Waves:
new tool for understanding the Universe,
complementary to other observational methods,
becoming a reality
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Acknowledgements

National Science Foundation
» NSF PHY-9210038 (Construction and Initial Operations)
» NSF PHY-0107417 (Current Operations)


Gary Sanders, LIGO Deputy Director
David Shoemaker, Advanced LIGO Project Lead
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