Deep inelastic scattering is the name given to a process used to probe the insides of hadrons (particularly the baryons, such as protons and neutrons), using electrons, muons and neutrinos. It provided the first convincing evidence of the reality of quarks, which up until that point had been considered by many to be a purely mathematical phenomenon. It is a relatively new process, first attempted in the 1960s and 1970s. It is an extension of Rutherford scattering to much higher energies of the scattering particle and thus to much finer resolution of the components of the nuclei.
Henry Way Kendall, Jerome Isaac Friedman and Richard E. Taylor were joint recipients of the Nobel Prize of 1990 "for their pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have been of essential importance for the development of the quark model in particle physics."[1]
https://en.wikipedia.org/wiki/Deep_inelastic_scattering
In particle physics, a glueball (also gluonium, gluon-ball) is a hypothetical composite particle.[1] It consists solely of gluon particles, without valence quarks. Such a state is possible because gluons carry color charge and experience the strong interaction between themselves. Glueballs are extremely difficult to identify in particle accelerators, because they mix with ordinary meson states.[2]
Theoretical calculations show that glueballs should exist at energy ranges accessible with current collidertechnology. However, due to the aforementioned difficulty (among others), they have so far not been observed and identified with certainty,[3] although phenomenological calculations have suggested that an experimentally identified glueball candidate, denoted , has properties consistent with those expected of a Standard Model glueball.[4]
The prediction that glueballs exist is one of the most important predictions of the Standard Model of particle physics that has not yet been confirmed experimentally.[5] Glueballs are the only particles predicted by the Standard Model with total angular momentum (J) (sometimes called "intrinsic spin") that could be either 2 or 3 in their ground states.
Experimental evidence was announced in 2021 by the TOTEM collaboration at the LHC in collaboration with the DØ collaboration at the former Tevatron collider at Fermilab of odderon (a composite gluonic particle with odd c-parity) exchange. This exchange, associated with a quarkless three-gluon vector glueball, was identified in the comparison of proton–proton and proton–antiproton scattering.[6][7][8]
https://en.wikipedia.org/wiki/Glueball
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