How does a LIGO interferometer work?

How does a LIGO interferometer work?

Gravitational waves cause space itself to stretch in one direction and simultaneously compress in a perpendicular direction. In LIGO, this causes one arm of the interferometer to get longer while the other gets shorter, then vice versa, back and forth as long as the wave is passing.

What type of interferometer is LIGO?

At their cores, LIGO’s interferometers are Michelson Interferometers, the same sort of device that was invented in the 1880’s: They are L-shaped (not all interferometers are this shape) Mirrors at the ends of the arms reflect light in order to create an interference pattern called ‘fringes’

Is LIGO is an laser interferometer?

LIGO stands for “Laser Interferometer Gravitational-wave Observatory”. It is the world’s largest gravitational wave observatory and a marvel of precision engineering.

Where is the LIGO interferometer?

The two primary research centers are located at the California Institute of Technology (Caltech) in Pasadena, California, and the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts. The detector sites in Hanford and Livingston are home to the interferometers that make LIGO an “observatory”.

How does an interferometer detect gravitational waves?

Changes in the distance along the arms are detected by looking at the interference pattern of light sent along the arms. A change would send the two beams out of phase and so would cause interference. The changes in space-time are very slight.

How does LIGO detect black holes?

As an antenna able to detect vibrations in the ‘medium’ of space-time, LIGO is akin to a human ear able to detect vibrations in a medium like air or water. This is the way in which LIGO has opened a new ‘window’ on the universe. Things like colliding black holes are utterly invisible to EM astronomers.

What is the main purpose of an interferometer in astronomy?

In astronomy, interferometers combine the light collected by more than one telescope. This lets telescopes act together as one bigger ‘virtual telescope’. The waves of light from each telescope are added together which makes them brighter. Interferometry makes it possible to see fainter objects in more detail.

What frequency can LIGO detect?

The Laser Interferometer Gravitational Wave Observatory (LIGO) consists of two widely separated 4 km laser interferometers designed to detect gravitational waves from distant astrophysical sources in the frequency range from 10 Hz to 10 kHz.

How accurate is an interferometer?

How accurate are interferometers? A state-of-the-art interferometer can measure distances to within 1 nanometer (one billionth of a meter, which is about the width of 10 hydrogen atoms), but like any other kind of measurement, it’s subject to errors.

How is LIGO so accurate?

Each houses a large-scale interferometer, a device that uses the interference of two beams of laser light to make the most precise distance measurements in the world. The animation begins with a simplified depiction of the LIGO instrument.

Is LIGO still operating?

LIGO resumes work in 2023 and will catch gravitational wave signals fainter than ever. The gravitational wave detector will be able to spot neutron star mergers as distant as 620 million light-years away.

How many countries have LIGO?

The LIGO Scientific Collaboration Established in 1997, the LSC includes over 1200 scientists from over 100 institutions in 18 different countries.