Laser Interferometer Space Antenna

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Laser Interferometer Space Antenna

• 12.409
• Arya Tafvizi

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LISA

• Its objective is to detect gravitational waves
  emitted from galactic binaries and extra-galactic
  massive black holes
• Planned to be
• launched in 2015
• It will operate for
• at least 5 years

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• Consists of 3 separate spacecrafts shaped like
  hockey pucks
• Fly 5 million km apart in a equilateral triangle
• The center of the triangle is 50 million km far
  from Earth. Orbits sun 20 degrees behind Earth

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Gravitational Waves

• Resemble Electromagnetic waves
• Contain information about their source
• Produced when a mass is accelerated
• They are propagating distortions in space-time
• Propagate with the
• speed of light

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Binaries

• Consists of a pair of objects, either or both can
  be black holes, neutron stars, white dwarfs or
  ordinary stars
• Einsteins theory of General Relativity predicts
  that the motion
• of these binary systems
• causes ripples in the
• curvature of spacetime

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Black holes

• Massive objects that nothing can escape them
• Their mass ranges from 3 to millions solar masses
• Merging black holes are huge sources of
  Gravitational Waves

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Interferometry

• Floating masses reflect light beams from one of
  the three spacecrafts
• Reflected beams are in initially in phase
• GWs cause disturb their phase by changing the
  distance between the masses and the detector in
  only one direction
• The photodector measures the intensity of the
  incoming beam

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courtesy of Professor
Scott Hughes