The Standard Model of particle physics is the theory describing three of the four known fundamental forces in the universe and classifying all known elementary particles. It was developed in stages throughout the latter half of the 20th century, through the work of many scientists worldwide, with the current formulation being finalized in the mid-1970s upon experimental confirmation of the existence of quarks. Since then, proof of the top quark (1995), the tau neutrino (2000), and the Higgs boson (2012) have added further credence to the Standard Model. In addition, the Standard Model has predicted various properties of weak neutral currents and the W and Z bosons with great accuracy.
The charm quark, charmed quark, or c quark is an elementary particle found in composite subatomic particles called hadrons such as the J/psi meson and the charmed baryons created in particle accelerator collisions. Several bosons, including the W and Z bosons and the Higgs boson, can decay into charm quarks. All charm quarks carry charm, a quantum number. This second generation particle is the third-most-massive quark with a mass of 1.27±0.02 GeV/c2 as measured in 2022 and a charge of +2/3 e.
A pentaquark is a human-made subatomic particle, consisting of four quarks and one antiquark bound together; they are not known to occur naturally, or exist outside of experiments specifically carried out to create them.
Technicolor theories are models of physics beyond the Standard Model that address electroweak gauge symmetry breaking, the mechanism through which W and Z bosons acquire masses. Early technicolor theories were modelled on quantum chromodynamics (QCD), the "color" theory of the strong nuclear force, which inspired their name.
In particle physics, a tetraquark is an exotic meson composed of four valence quarks. A tetraquark state has long been suspected to be allowed by quantum chromodynamics, the modern theory of strong interactions. A tetraquark state is an example of an exotic hadron which lies outside the conventional quark model classification. A number of different types of tetraquark have been observed.
The
J/ψ
(J/psi) meson is a subatomic particle, a flavor-neutral meson consisting of a charm quark and a charm antiquark. Mesons formed by a bound state of a charm quark and a charm anti-quark are generally known as "charmonium" or psions. The
J/ψ
is the most common form of charmonium, due to its spin of 1 and its low rest mass. The
J/ψ
has a rest mass of 3.0969 GeV/c2, just above that of the
η
c, and a mean lifetime of 7.2×10−21 s. This lifetime was about a thousand times longer than expected.
The Drell–Yan process occurs in high energy hadron–hadron scattering. It takes place when a quark of one hadron and an antiquark of another hadron annihilate, creating a virtual photon or Z boson which then decays into a pair of oppositely-charged leptons. Importantly, the energy of the colliding quark-antiquark pair can be almost entirely transformed into the mass of new particles. This process was first suggested by Sidney Drell and Tung-Mow Yan in 1970 to describe the production of lepton–antilepton pairs in high-energy hadron collisions. Experimentally, this process was first observed by J. H. Christenson et al. in proton–uranium collisions at the Alternating Gradient Synchrotron.
Michael Edward Peskin is an American theoretical physicist. He is currently a professor in the theory group at the SLAC National Accelerator Laboratory.
The J. J. Sakurai Prize for Theoretical Particle Physics, is presented by the American Physical Society at its annual April Meeting, and honors outstanding achievement in particle physics theory. The prize consists of a monetary award (US$10,000), a certificate citing the contributions recognized by the award, and a travel allowance for the recipient to attend the presentation. The award is endowed by the family and friends of particle physicist J. J. Sakurai. The prize has been awarded annually since 1985.
William Allan Bardeen is an American theoretical physicist who worked at the Fermi National Accelerator Laboratory. He is renowned for his foundational work on the chiral anomaly, the Yang-Mills and gravitational anomalies, the development of quantum chromodynamics and the scheme frequently used in perturbative analysis of experimentally observable processes such as deep inelastic scattering, high energy collisions and flavor changing processes.
Chris Quigg is an American theoretical physicist at the Fermi National Accelerator Laboratory (Fermilab). He graduated from Yale University in 1966 and received his Ph.D. in 1970 under the tutelage of J. D. Jackson at the University of California, Berkeley. He has been an associate professor at the Institute for Theoretical Physics, State University of New York, Stony Brook, and was head of the Theoretical Physics Department at Fermilab from 1977 to 1987.
Estia Joseph Eichten, is an American theoretical physicist, of the Fermi National Accelerator Laboratory (Fermilab). He received his Ph.D. in 1972 from the MIT Center for Theoretical Physics, where he was a student of Roman Jackiw's, and was associate professor of physics at Harvard before joining the Fermilab Theoretical Physics Department in 1982.
Christopher T. Hill is an American theoretical physicist at the Fermi National Accelerator Laboratory who did undergraduate work in physics at M.I.T., and graduate work at Caltech. Hill's Ph.D. thesis, "Higgs Scalars and the Nonleptonic Weak Interactions" (1977) contains one of the first detailed discussions of the two-Higgs-doublet model and its impact upon weak interactions. His work mainly focuses on new physics that can be probed in laboratory experiments or cosmology.
Kurt Gottfried was an Austrian-born American physicist who was professor emeritus of physics at Cornell University. He was known for his work in the areas of quantum mechanics and particle physics and was also a co-founder with Henry Way Kendall of the Union of Concerned Scientists. He wrote extensively in the areas of physics and arms control.
In particle physics, W′ and Z′ bosons refer to hypothetical gauge bosons that arise from extensions of the electroweak symmetry of the Standard Model. They are named in analogy with the Standard Model W and Z bosons.
Goran Senjanović is a theoretical physicist at the Abdus Salam International Centre for Theoretical Physics (ICTP). He received his Ph.D. at the City College of New York in 1978, under the supervision of Rabindra Mohapatra. Before joining the ICTP in 1991, he worked as a staff member at the Brookhaven National Laboratory and as a professor of physics at the University of Zagreb. His major research interests are neutrino physics, unification of elementary particle forces, baryon and lepton number violation and supersymmetry.
Tung-Mow Yan is a Taiwanese-born American physicist, who has specialized in theoretical particle physics; primarily in the structure of elementary particles, the Standard Model, and quantum chromodynamics. He is professor emeritus at Cornell University.
Kenneth Alan Johnson was an American theoretical physicist. He was professor of physics at MIT, a leader in the study of quantum field theories and the quark substructure of matter. Johnson contributed to the understanding of symmetry and anomalies in quantum field theories and to models of quark confinement and dynamics in quantum chromodynamics.
In particle physics, the Cornell potential is an effective method to account for the confinement of quarks in quantum chromodynamics (QCD). It was developed by Estia J. Eichten, Kurt Gottfried, Toichiro Kinoshita, John Kogut, Kenneth Lane and Tung-Mow Yan at Cornell University in the 1970s to explain the masses of quarkonium states and account for the relation between the mass and angular momentum of the hadron. The potential has the form:
A cosmological phase transition is a physical process, whereby the overall state of matter changes together across the whole universe. The success of the Big Bang model led researchers to conjecture possible cosmological phase transitions taking place in the very early universe, at a time when it was much hotter and denser than today.
