Initial LIGO, Advanced LIGO and the HAMSAS Procurement

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Initial LIGO, Advanced LIGOand the HAM-SAS
Procurement

• Dennis Coyne
• HAM-SAS Bidders Conference
• _at_ LIGO Laboratory, Caltech
• 25 October 2005

Livingston, LA
Hanford, WA
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Initial LIGO

• LIGO is an NSF Sponsored Large Science Project
• Start the field of Gravitational Wave Observation
  in the U.S.
• Join the international array of gravitational
  wave interferometers
• Give plausible detection with an initial detector
  sensitivity
• 300M for 2 Observatories including 3
  Interferometers
• Caltech and MIT organizations comprise the LIGO
  Laboratory (Caltech has contractual and financial
  responsibility)
• Initial LIGO
• Each Interferometer is L-shaped with 4 km long
  arms comprised of 1.2 m diameter vacuum tubes
  plus 3 m diameter chambers
• Each Observatory has one of the worlds largest
  Ultra-High Vacuum (UHV) systems

Radiation of Gravitational Waves from binary
inspiral system
Leslie is an applicant
LISA (Space-based version of LIGO)
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Interferometry for Detection
Suspended mass Michelson-type interferometers on
earths surface detect distant astrophysical
sources International network (LIGO, Virgo, GEO,
TAMA) enable locating sources and decomposing
polarization of gravitational waves.
The effect is greatly exaggerated!! If the ring
were 4.5 light years in diameter, it would change
by only a hairs width LIGO (4 km), stretch
(squash) 10-18 m will be detected at
frequencies of 10 Hz to 104 Hz. It can detect
gravitational waves from a distance of 600 106
light years
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Initial LIGO Going into Continuous Operations

• Continuous Observatory Operations to Start
  November
• _at_ design sensitivity of 10-19 m/rHz
• 18 month duration
• Modest upgrades before Advanced LIGO also planned

Seismic Noise
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Initial LIGO Seismic Isolation Systems

• Reduce in-band seismic motion by 4 - 6 orders of
  magnitude
• Little or no attenuation below 10Hz
  amplification at stack mode resonances
• Large range actuation for initial alignment and
  drift compensation
• Quiet actuation to correct for Earth tides and
  microseism at 0.15 Hz during observation

BSC Chamber
HAM Chamber
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Seismic System Performance
HAM stack in air
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Advanced LIGO

• Advanced LIGO
• Factor 10 in amplitude sensitivity
• Factor 4 lower frequency
• Tunable

Sky map showing locations of superclusters,
walls, and voids of galaxies within about 500
million light years. Superimposed circles show
the range of LIGO (orange inner circle) and the
10 times larger range of AdvLIGO (purple outer
circle). The milky way is at the center in this
representation. Credit the underlying black and
white image with names of clusters and voids is
by Richard Powell the superimposed color circles
were added by Beverly Berger, Division of
Physics, NSF.
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Construction Project Status

• NSB endorsed the Advanced LIGO construction
  proposal (Oct 04)
• Contingent upon an integrated year of observation
  with Initial LIGO
• Requested 185M, plus 25M from International
  Partner Contributions (UK, Ger, Aus)
• NSF Presidential Out-year Budget includes LIGO!
• LIGO is one of 3 proposed new start projects in
  the next 3 years
• NSF has proposed an FY08 funding start

• Construction Schedule (for NSF FY08 funding
  start)
• Start fabrication in FY2008
• Shutdown Livingston in FY10, but continue Hanford
  operations
• Shutdown Hanford in FY11
• Resume coincidental observations in FY13

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SEISMIC ISOLATION DEVELOPMENT
STIFF APPROACH
SOFT APPROACH
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HAM-SAS Mechanical FabricationStatement Of Work
(SOW)

• Fabricate the parts lists in the BOM
• Machining
• large aluminum parts, stainless steel, PEEK,
  maraging steel
• Machining fluids must be water soluble free of
  sulfur, chlorine and silicone
• Weldments full penetration
• Heat treat maraging steel blades
• Assembly
• dirty assembly fit check
• tune Geometric Anti-Spring (GAS) assemblies
  Inverted Pendulula
• Test assist LIGO Personnel
• horizontal and vertical transfer functions
  measured using calibrator setups
• Disassemble
• Clean and Bake parts
• Clean Assembly
• Package Ship

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HAM-SAS MechanicalFabrication Challenges
Unique Aspects

• Build to Print (no design work), except
• UHV restrictions on machining, welding, handling
• Drawings are dimensioned properly, but tolerances
  are only indicative, e.g. at maximum material
  conditions parts may not fit
• Expect contractor to match parts as part of the
  assembly process
• Coil winding potting
• Maraging steel
• Heat treatment
• Handling highly stressed blades
• Assembly requires tuning/adjustment (with
  guidance from LIGO Staff)
• Host and facilitate performance testing by LIGO
  personnel
• UHV cleaning, air baking, contamination control
  and packaging
• Final Assembly in Clean Room (Class 100)