Four telescopes dedicated primarily to observing gamma rays, which are high-energy electromagnetic waves, have been completed. They are expected to contribute to exploring the nature of dark matter by observing the universe up to 12 billion years ago.

The Cherenkov Telescope Array Observatory (CTAO), an international joint astronomical observation facility, announced that it will hold a completion ceremony on the 15th (local time) for the "LST Array," an observation facility composed of four Large-Sized Telescopes (LSTs) at the Roque de los Muchachos Observatory on La Palma Island, Spain.

The newly completed LST Array is the core facility of "CTAO-North," which is currently under construction in the Northern Hemisphere. By adding the newly constructed LST-2, LST-3, and LST-4 to LST-1, which was built earlier in 2018, it observes high-energy gamma rays simultaneously from multiple directions. It is designed to observe gamma rays in the range of approximately 20 GeV (gigaelectronvolts, a unit of energy) to several TeV (teraelectronvolts, where 1 TeV is 1,000 GeV).

Given that gamma rays are mainly generated in extreme celestial bodies and phenomena in the universe such as black holes, neutron stars, and supernova explosions, they will be used to understand extreme cosmic phenomena. Although high-energy gamma rays are absorbed through interactions with other light while traveling, LSTs are advantageous for observing distant celestial bodies because they can capture relatively low-energy gamma rays. Researchers expect that through the LST Array, they will be able to observe celestial bodies from about 12 billion years ago, when the age of the universe—currently 13.8 billion years—was less than 2 billion years.

Each telescope is equipped with a 23-meter diameter reflector and an ultra-high-speed camera. They operate by capturing "Cherenkov light," which appears in "particle showers"—a chain reaction caused when gamma rays coming from space collide with the Earth's atmosphere. Cherenkov light is a faint light instantaneously emitted as particles move faster than the speed of light in the atmosphere.

The CTAO stated, "Following test operations and system integration, we plan to prepare for official operations," adding, "We intend to build the world's largest gamma-ray astronomical observation facility by installing more than 60 telescopes."

[ⓒ Global Economic Times. 무단전재-재배포 금지]