CTAO

CTAO

Cherenkov Telescope Array Observatory

SHORT DESCRIPTION

CTAO will be the most powerful observatory in the world for the study of the universe through the ground-based detection of very high-energy gamma rays. It is a project involving countries and researchers from all over the world for the construction of two large astronomical observatories (arrays), one in the southern hemisphere and one in the northern hemisphere. Gamma rays are emitted by some of the most extreme and powerful objects in the Universe, such as supermassive black holes and supernovae.

CTAO, with its large collecting area and wide sky coverage, will be the world’s largest and most sensitive high-energy gamma-ray observatory. The two arrays will detect gamma rays with unprecedented precision and together will be up to 10 times more sensitive than existing instruments.

To provide the required high sensitivity over a wide energy range, from a few tens of GeV up to a few hundred TeV, CTAO is composed of three different types of telescopes: the LSTs (Large Size Telescopes) with a diameter of 23 m, the MSTs (Medium Size Telescopes) with a diameter of 12 m and the SSTs (Small Size Telescopes) with a diameter of 4 m. In particular the SSTs are the most numerous and will provide sensitivity at the highest energies from ~0.5 up to ~300 TeV.

According to the current approved layout, the so-called Alpha Configuration, CTAO will comprise 64 telescopes worldwide, with 13 telescopes in the Northern Hemisphere (4 LST and 9 MST) and 51 telescopes in the Southern Hemisphere (14 MST and 37 SST) to which 2 additional LSTs have been added, funded by the Italian PNRR. The Northern Hemisphere site (CTAO-North) is located at the Instituto de Astrofísica de Canarias Observatorio del Roque de los Muchachos, on the island of La Palma in the Canary Islands. The Southern site (CTAO-South) is located at ESO’s Paranal Observatory, about ten kilometres south-east of the Very Large Telescope. This is one of the driest and most isolated regions on Earth: an astronomical paradise. The integration of CTAO into the existing Paranal-Armazones infrastructure will allow the exploitation of ESO’s state-of-the-art facilities.

ROLE OF THE OBSERVATORY

The SST telescopes are developed by an international consortium of a few hundred people and is coordinated by INAF, which provides more than 60% of the funds needed for their construction. The Brera Astronomical Observatory coordinates the participation of the various INAF institutes in the project, under the responsibility of Gianpiero Tagliaferri who also chairs the international committee that manages the project. Therefore, our institute has a fundamental role in the construction of this international observatory having the responsibility of building the SST telescopes, which in turn are based on the ASTRI telescopes, which are a sort of precursor of the SSTs, also developed by the Brera Astronomical Observatory under the guidance of Giovanni Pareschi (see link to the ASTRI project).

The Brera Astronomical Observatory also coordinates, under the leadership of Giovanni Pareschi, the development and construction of the optics of the two LST telescopes that will be built at the southern site of CTAO thanks to the contribution of Italian funds from the PNRR.

OBSERVATORY STAFF INVOLVED
  • Stefano Basso
  • Maria Grazia Bernardini
  • Andrea Bianco
  • Alessandro Caccianiga
  • Massimiliano Casiraghi
  • Stefano Covino
  • Paolo D’Avanzo
  • Roberto Della ceca
  • Dino Fugazza
  • Giancarlo Ghirlanda
  • Simone Iovenitti
  • Giuseppe Malaspina
  • Alida Marchetti
  • Rachele Millul
  • Lara Nava
  • Giovanni Pareschi
  • Gabriele Ponti
  • Marco Riva
  • Patrizia Romano
  • Giorgia Sironi
  • Daniele Spiga
  • Gianpiero Tagliaferri
  • Fabrizio Tavecchio
  • Stefano Vercellone
  • Anna Wolter
TIMELINE

2010 –

WEBSITE

CTAO

CONTACT

gianpiero.tagliaferri AT inaf.it

CREDIT

Web page content: G. Tagliaferri.

Insight: Science with CTAO

CTAO will be the first “open” gamma-ray observatory: its data and analysis software will be made available worldwide (after a proprietary period), involving a large research community in astronomy and high-energy physics.

Its scientific potential is extremely broad, from understanding the role of relativistic cosmic particles to the search for dark matter. Observations carried out with CTAO will aim to understand the influence of high-energy particles in the evolution of cosmic systems and to study some of the most extreme and violent events occurring in the high-energy Universe. CTAO will explore environments from the immediate vicinity of black holes to cosmic voids on the largest scales. It could also lead to entirely new physics as it studies the nature of matter and forces beyond the standard model.

Although Earth’s atmosphere prevents gamma rays from reaching the surface, their interactions with the atmosphere create extremely high-energy particles. These particles travel faster than the speed of light in air and as a result emit a flash of blue radiation (Cherenkov light), similar to a sonic boom created by a plane traveling faster than the speed of sound. CTAO’s mirrors and high-speed cameras will capture these very short-duration (nanosecond) flashes and pinpoint their direction. This will allow each gamma ray to be traced back to its cosmic source, allowing astronomers to tackle some of the most enduring mysteries in astrophysics.

CTAO will have the ability to detect gamma rays in the energy range from a few tens of GeV to hundreds of TeV. At the lowest energies, CTAO will investigate time-varying events (transients) in the distant Universe; at the highest energies, it will push observational astronomy into a previously unexplored part of the electromagnetic spectrum to offer a completely new view of the sky.

CTAO will see the sky at higher energy resolution than ever before, allowing it to search for annihilating dark matter particles, and it will also be able to rapidly repoint to catch gamma-ray bursts as they explode.