3 Little-Known Facts About Neutrinos, aka, “The Ghost Particle”

One of the persisting challenges in physics is the detection, measurement, and understanding of neutrinos, also known as "the ghost particle."

A recently-published study from the United States' Department of Energy Oak Ridge National Library settles a discrepancy surrounding the biggest contributor of unwanted background signals in specialized neutrino detectors. The report, appearing in Physical Review Letters, identifies a reaction in which the new measurement varies significantly from historical data.

First postulated by Austrian theoretical physicist Wolfgang Pauli in 1930, neutrinos were used to explain how beta decay could conserve energy, momentum, and spin. Almost a century later, many mysteries surrounding this elementary particle continue to baffle and interest scientists all over the world. Here are some little-known facts about nature's "ghost particles":

1. Neutrinos are among the most abundant particles in The Universe

Large amounts of neutrinos move across all directions of space close to the speed of light. Scientists estimate that about 100 billion solar neutrinos pass through every square centimeter of your body - a surface area roughly the size of your fingertips!

Neutrinos pass through Earth and everything in it, regardless of location or time. Our own sun produces energy in its core through a process known as nuclear fusion, specifically the proton-proton (PP) chain reaction. This event involves two protons coming together to form a deuterium, a Hydrogen isotope, and giving off positrons and neutrinos in the process.

2. They Are Called "Ghost Particles" Because They're Nearly Undetectable

Despite their staggering abundance in the universe, neutrinos are unusually difficult to detect. The human body, the earth's core, and the emptiness of space are thought to be no different when it comes to neutrinos. Additionally, neutrinos are unique since they have no electrical charges. Its name, neutrino, comes from the fact that it is electrically neutral, and its rest mass is so minute, it was previously thought to be zero.

Advancements in science and technology have allowed the detection of neutrinos, but only through their interaction with matter as we know them. For example, in 2017, members of the COHERENT collaboration reported detecting coherent neutrino scattering. Researchers used a sensitive cesium iodide doped with sodium. When a nucleus in the mixture recoils in a crystal, it gives off a faint yet observable flash of light.

3. Studies Attempt to Use Neutrinos as Stellar Warning Signals

Physicists were able to understand a crucial part of the Sun's nuclear fusion processes with neutrinos' help. Detecting these ghost particles confirmed the theoretical model that postulates the Sun, generating its energy through a chain reaction that includes carbon and nitrogen nuclei. Four protons form a helium nucleus, with the process releasing two neutrinos.

Additionally, neutrinos are believed to provide a unique signature before a star becomes a supernova. For the star's life cycle's carbon burning phase, neutrinos are expected to be emitted with a particular signature. Leading to its transformation into a supernova, neutrinos are generated with higher energies, and in the final few hours of the star's life, neutrinos cross an energy threshold.

Check out more news and information on Neutrinos in Science Times.