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Progress on the practical integration of cryogenics to gravitational wave detectors

Edgard Bonilla,

with the help of the Stanford LIGO group

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Questions?

About me!

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Quick Intro:

Gravitational Waves

What are they?

Ripples in spacetime!

Predicted by General Relativity

How do they look?

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Quick Intro:

Gravitational Waves

Real effect is 1/10,000 times the size of a proton!

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Quick Intro:

Gravitational Waves

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Quick Intro:

GW Observation

2015

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GW Observatories

LIGO Hanford Observatory (LHO)

Hanford, WA

LIGO Livingston Observatory (LLO)

Livingston, LA

Virgo Interferometer

near Pisa, Italy

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Test Masses

How do we improve

the detectors?

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Complicated!

How do we improve

the detectors?

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Quick Intro:

Gravitational Waves

What do we want to observe in the future?

Compact binary collisions

(colliding black holes or neutron stars)

Continuous

(accretion disks, black hole systems)

Bursts

(supernovae)

Background

(echoes from the Big Bang)

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How do we improve

the detectors?

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Advanced LIGO Noise budget

How do we improve

the detectors?

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Advanced LIGO Noise budget (realistic)

How do we improve

the detectors?

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Heavier masses

Better optical coatings

More laser power

Lower temperature

Squeezed Light

Longer detector

Advanced LIGO Noise budget

How do we improve

the detectors?

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Heavier masses

Better optical coatings

More laser power

Longer detector

Squeezed Light

Better thermal conduction

No point absorbers

Different mass material

Different wavelength

More suspensions

Better suspensions

Low-frequency control

Better angular control

Better sensors

Cryo sensors

Lower temperature

Cryogenics

How do we improve

the detectors?

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How do we improve

the detectors?

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Stanford LIGO group

(and friends)

Support and improve the current detectors

Research technology for future detectors

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Stanford LIGO group

(and friends)

Support and improve the current detectors

Research technology for future detectors

  • Suspension modelling
  • Electromechanical modelling
  • Johnson Noise estimates
  • Testing control schemes
  • Reduced order models

​

  • Cryogenics
    • Noise estimates
    • Technology demonstrations
  • Electro-Optic calculations
  • Longitudinal baffling

​

​

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Newtonian

Scattered Light

Noise Estimation

Coupling paths studied

Displacement:

Density:

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From prototyping experience

From density Newtonian modelling:

From scattered light modelling:

Technology demonstrations

  • Suppress boiling in operation
  • Isolate the inner shields

Cryo shield

prototype

Subcooled nitrogen

operation

Test Mass

124 K

Heat Sink

SEISMICALLY ISOLATED PLATFORM

Follow

77 K

Nitrogen chiller

65 K

  • Faster iteration time

Exchange gas

cooldown

Test Mass

124 K