Context: The MACE telescope in Hanle, Ladakh, represents a significant leap in India’s gamma-ray astronomy capabilities, building on over five decades of involvement in this field. MACE is poised to answer fundamental questions in high-energy astrophysics and particle physics, particularly regarding the nature of dark matter and WIMPs.

About MACE

• The Major Atmospheric Cherenkov Experiment (MACE) telescope, inaugurated in Hanle, Ladakh, is a state-of-the-art gamma-ray telescope designed to study high-energy cosmic phenomena.

• Highest Imaging Cherenkov Telescope: Located at around 3 km above sea level, MACE is the highest of its kind in the world.

• Largest Dish in Asia: With a 21-meter-wide dish, it is the largest imaging Cherenkov telescope in Asia and the second-largest globally.

Key Features

• Gamma Rays and Cherenkov Radiation: Gamma rays have the shortest wavelength and highest energy in the electromagnetic spectrum. While they are harmful to living organisms, Earth's atmosphere blocks most gamma rays. When these rays hit the atmosphere, they produce Cherenkov radiation—a faint blue light—caused by charged particles traveling faster than light in air.

• Imaging Atmospheric Cherenkov Telescope (IACT): MACE is an IACT, capable of detecting Cherenkov radiation to study high-energy gamma rays from cosmic sources.

• Collaboration and Construction: The facility was built by major Indian institutions, including the Bhabha Atomic Research Centre (BARC), Tata Institute of Fundamental Research (TIFR), Electronics Corporation of India Ltd. (ECIL), and the Indian Institute of Astrophysics (IIA).

Technology

• Light Collector and Mirrors: MACE uses 356 mirror panels, each with four smaller mirrors arranged in a honeycomb pattern. This design enhances stability and reflective area while reducing empty space between mirrors. Similar designs are used in other space observatories like the James Webb Space Telescope.

• High-Resolution Camera: The telescope is equipped with a camera containing 1,088 photomultiplier tubes that detect and amplify faint light signals. Data processing is done in real-time through specialized electronics.

• Mobility and Mount: MACE’s 180-ton telescope moves along a 27-meter-wide curved track, with an altitude-azimuth mount, allowing it to adjust its view both vertically and horizontally.

Scientific Goals

• High-Energy Gamma Ray Study: MACE primarily aims to study gamma rays with energies above 20 billion eV. This includes investigating black holes, gamma-ray pulsars, blazars, and gamma-ray bursts.

• Search for Dark Matter: One of MACE’s significant goals is to explore the elusive particles that make up dark matter, which is believed to account for more than 85% of the universe’s mass. One candidate for dark matter particles is WIMPs (Weakly Interacting Massive Particles). When WIMPs collide and annihilate each other, they may produce high-energy gamma rays, which MACE is designed to detect.