A research group led by Tohoku University, the High Energy Accelerator Research Organization (KEK), and the Japan Atomic Energy Agency (JAEA) has discovered that the basic property of symmetry, which adds special particles to the nucleus, is greatly disrupted.There is a possibility that the nature of the "nuclear force" that connects the protons and neutrons that make up the atomic nucleus can be elucidated.
The properties of an atomic nucleus, such as its mass and internal structure, are determined by the number of protons and neutrons contained in it.It is known that nuclei in which the number of positively charged protons and the number of uncharged neutrons are exchanged have a property called "charge symmetry" in which non-charged properties are very similar.This is because the nuclear forces acting on protons and neutrons are the same, so the total amount of acting force does not change even if the numbers of each are exchanged.This was thought to be the same in the presence of lambda particles.However, when the lambda particle exists inside the nucleus, it was discovered that the mass of the one in which the numbers of protons and neutrons are exchanged is different.I don't know the reason yet, but it is expected to be the key to unraveling the whole picture of nuclear force.
We learn in junior high school that atomic nuclei are made up of protons and neutrons, but it may be surprising that there are still things we do not know.If this mystery can be solved, it may be possible to answer the question of why atomic nuclei exist in this universe.
