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Published in Splinter Robert, Illustrated Encyclopedia of Applied and Engineering Physics, 2017
[atomic, general] Elementary particle (gluon) named after the physicist Satyendra Nath Bose (1894–1974) who provided the critical information with respect to the description and discovery. Bosons provide the vehicle for the strong interaction between quarks. The boson has integer spin values (in contrast to fermions with half-integer spin, named after Enrico Fermi [1901–1954]). Specific vector bosons are W+,W−, and Z particles as well as the photon.
Towards highly accurate calculations of parity violation in chiral molecules: relativistic coupled-cluster theory including QED-effects
Published in Molecular Physics, 2021
It was Lee and Yang who in 1956 pointed out that there was insufficient experimental evidence for the conservation of parity in processes involving the weak interaction and proposed experiments to test possible parity violation [5], soon to be confirmed by experiments [6–9]. The processes that were studied are mediated by charged vector bosons, in contrast to the neutral photon of electromagnetic interactions, and are therefore incompatible with stable atoms and molecules. The situation changed with the development of electroweak theory [10–12] and in particular the prediction of the existence of a neutral partner, , of the charged bosons. Early studies about the feasibility of observing parity violation in stable atoms were rather pessimistic [13,14], but limited attention to the hydrogen atom. M. A. and C. Bouchiat noted that PV has a strong scaling with nuclear charge and therefore suggested to look for such effects in heavy atoms [15,16] and, indeed, the first observation of atomic PV was in the form of optical activity in a vapour of bismuth atoms [17,18]. Since then PV has been observed in several heavy atoms: thallium [19–23], cesium [24–29], lead [30–32], bismuth [33] and ytterbium [34,35]. For a recent review on atomic parity violation, see Ref. [36].