Some 250 scientists and officials have attended a ceremony today to mark the completion of a giant telescope complex in La Palma, Spain.
The construction of four 23 m-diameter telescopes belong to the Large-Sized Telescope (LST) array at the Roque de los Muchachos Observatory in La Palma, Spain.
The telescopes are designed to detect the faint Cherenkov light flashes when very high-energy gamma rays interact with the Earth’s atmosphere.
The LSTs are the most sensitive instruments in the world for observing gamma rays at energies between approximately 20 GeV and 3 TeV.
The first LST-1 telescope was built in 2020 and has already completed observations of pulsars, studies of active galactic nuclei at cosmological distances and rapid follow-up observations of transient phenomena such as novae and gamma-ray bursts.
The three other telescopes now join LST-1 and by observing the same gamma-ray showers simultaneously from multiple directions, it will provide improved sensitivity, angular resolution and energy reconstruction.
Their sensitivity to the lowest-energy gamma rays will enable astronomers to detect and study bright gamma-ray bursts at high redshift, potentially extending gamma-ray observations to sources at redshifts of around z∼4 to provide new insights into the early universe.
“The completion of the LST sub-array is the culmination of more than 15 years of international collaboration and technological innovation,” says Japanese astrophysicist Masahiro Teshima, who is principal investigator of the LST collaboration. “These telescopes will allow us to explore some of the most extreme environments in the universe, including supermassive black holes, neutron stars and the nature of dark matter.”
North-south divide
The telescope will form part of the Cherenkov Telescope Array Observatory (CTAO), which when operational in 2028 will operate between 20 GeV and 300 TeV and be the world’s most powerful observatory for gamma-ray astronomy.
The CTAO will consist of six LST telescopes as well as two other arrays: 23 telescopes belonging to the Medium-Sized Telescope (MST), which will operate between 80 GeV and 50 TeV, and 37 telescopes for the Small-Sized Telescope (SST) that will work between 2 TeV and 300 TeV.
The 66 telescopes will be distributed between CTAO-North at La Palma and CTAO-South at the Paranal Observatory in the Atacama Desert in Chile.
The LSTs form the low-energy core of CTAO-North and over the coming years they will undergo commissioning and be integrated into CTAO operations.
