particle physics Particle physics or high-energy physics is the study of Elementary particle, fundamental particles and fundamental interaction, forces that constitute matter and radiation. The field also studies combinations of elementary particles up to the s ...

, V was a generic name for heavy, unstable

subatomic particle In physics, a subatomic particle is a particle smaller than an atom. According to the Standard Model of particle physics, a subatomic particle can be either a composite particle, which is composed of other particles (for example, a baryon, lik ...

s that decay into a pair of particles, thereby producing a characteristic letter V in a

bubble chamber A bubble chamber is a vessel filled with a superheated transparent liquid (most often liquid hydrogen) used to detect electrically charged particles moving through it. It was invented in 1952 by Donald A. Glaser, for which he was awarded th ...

or other

particle detector In experimental and applied particle physics, nuclear physics, and nuclear engineering, a particle detector, also known as a radiation detector, is a device used to detect, track, and/or identify ionizing elementary particle, particles, such as t ...

. Such particles were first detected in

cosmic ray Cosmic rays or astroparticles are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the ...

interactions in the atmosphere in the late 1940s and were first produced using the

Cosmotron The Cosmotron was a particle accelerator, specifically a proton synchrotron, at Brookhaven National Laboratory. Its construction was approved by the U.S. Atomic Energy Commission in 1948, reaching its full energy in 1953, and continuing to run ...

particle accelerator A particle accelerator is a machine that uses electromagnetic fields to propel electric charge, charged particles to very high speeds and energies to contain them in well-defined particle beam, beams. Small accelerators are used for fundamental ...

Brookhaven National Laboratory Brookhaven National Laboratory (BNL) is a United States Department of Energy national laboratories, United States Department of Energy national laboratory located in Upton, New York, a hamlet of the Brookhaven, New York, Town of Brookhaven. It w ...

in the 1950s. Since all such particles have now been identified and given specific names, for instance

Kaon In particle physics, a kaon, also called a K meson and denoted , is any of a group of four mesons distinguished by a quantum number called strangeness. In the quark model they are understood to be bound states of a strange quark (or antiquark ...

s or Sigma baryons, this term has fallen into disuse. V⁰ is still used on occasion to refer generally to

neutral particle In physics, a neutral particle is a particle without an electric charge, such as a neutron. Stable or long-lived neutral particles Long-lived neutral particles provide a challenge in the construction of particle detectors, because they do not int ...

s that may confuse the

B-tagging b-tagging is a method of particle jet, jet flavor tagging used in modern particle physics experiments. It is the identification (or "tagging") of jets originating from bottom quarks (or b quarks, hence the name). Importance b-tagging is important ...

algorithms in a modern particle detector, as is used in Section 7 o
this ATLAS conference note

References

* * Subatomic particles {{particle-stub