Researchers Begin Using the Kilometre-Scale Neutrino Telescope to Search for Ghost Particles.
The Kilometre-Scale Neutrino Telescope (KM3NeT) is currently under construction to search for high-energy neutrinos, aiming to study them and identify the astrophysical sources that propel them throughout the universe. To achieve this, KM3NeT utilizes the ocean as a detection medium and exploits the effects that occur when subatomic particles travel faster than the speed of light in a specific environment, as reported by IFL Science on August 8.
Simulation of ghost particle detectors mounted on long strings. (Photo: Wikipedia).
The speed of light in a vacuum is the absolute speed limit of the universe. No object can travel faster than 300,000 km/s, according to Einstein’s research, as it would require infinite energy to do so. However, this does not mean that light cannot be surpassed under certain conditions. When this occurs, a strange effect called Cherenkov radiation can emerge. For instance, in water, light travels at a slower speed of 200,000 km/s. Any particle wishing to exceed that speed would require 175 kiloelectron volts of energy.
In 1934, Soviet physicist Pavel Cherenkov observed what happened after bombarding water with radiation. A blue light, now known as Cherenkov light or Cherenkov radiation, emanated from the water. He and his two colleagues, Il´ja Mikhailovich Frank and Igor Yevgenyevich Tamm, identified the cause of this unusual light. Charged subatomic particles moving faster than the speed of light in water produce an effect similar to a sonic boom (which occurs when an aircraft exceeds the speed of sound). For this research, they were awarded the Nobel Prize in Physics in 1958.
KM3NeT aims to detect Cherenkov light in the ocean, produced by the interaction of neutrinos with seawater. The Astroparticle Research with Cosmics in the Abyss (ARCA) forms the largest component of KM3NeT. Detectors are attached to long strings, with the detectors at the end of the strings located 3,500 meters below the surface of the Mediterranean Sea. The more detectors there are, the better they can filter out noise signals in the ocean, such as the decay of potassium-40.
ARCA appears to have detected an interesting event, as described by Francis Halzen, a physicist at the University of Wisconsin – Madison. The very bright event observed by ARCA has only recently been revealed by neutrino physicist João Coelho at the Neutrino 2024 conference in Milan, Italy. According to him, this event is “truly extraordinary, surpassing anything else.” Currently, researchers are keeping the direction and timing of the detection confidential to prevent other groups from using the information to locate the cosmic source.
Neutrinos are known as “ghost particles” because they can easily pass through solid objects. Neutrinos interact very weakly with matter. A neutrino can travel a distance of one light-year (10 trillion kilometers) through lead without colliding with any atoms.
