Showing papers on "Strangeness published in 1979"
TL;DR: In this article, the thermodynamic potential of quantum chromodynamics is calculated in order 1, α c and α c 3 2, where αc is a function of the temperature and chemical potentials.
423 citations
TL;DR: In this paper, the authors proposed that extended, massive, multiquark states possessing great strangeness may be metastable, on the basis of the Massachusetts Institute of Technology bag model of hadrons.
Abstract: This Letter proposes, on the basis of the Massachusetts Institute of Technology bag model of hadrons, that extended, massive, multiquark states possessing great strangeness may be metastable. Such novel states of matter would have strangeness to baryon-number ratio vertical-barSvertical-bar/A approx. = 2 with A > or approx. = 10 and estimated lifetime > or approx. = 10/sup -4/ sec.
218 citations
TL;DR: The strangeness exchange reaction on 32 S and 40 Ca has been studied in this article, where the strongest transitions are assigned to states having a configuration with the Λ particle in a 1s, 1p, 1d, 2s, and 1f orbit coupled to the nuclear core.
68 citations
TL;DR: In this article, the strangeness exchange reactions on p and s-shell nuclei are analyzed using the shell-model to describe the structure of the hypernuclei information about the Λ-nuclues interaction.
66 citations
TL;DR: For example, the authors argued that science, like the arts, admits aesthetic criteria; we seek theories that display a proper conformity of the parts to one another and to the whole, while still showing some strangeness in their proportion.
Abstract: Science, like the arts, admits aesthetic criteria; we seek theories that display “a proper conformity of the parts to one another and to the whole” while still showing “some strangeness in their proportion.”
38 citations
Book•
01 Jan 1979
TL;DR: The Whys of Subnuclear Physics: Why Is There Charm, Strangeness, Colour and All That?- Do Mesons Fill SU(3) Nonets?- The Properties of Charmonium and Charm Particles- Recent Results from DASP- New Particles or "Why I Believe in Quarks"- New Particle production in Hadronic Interactions- Review of Lepton Production in Hadron - Hadron Collisions- Narrow Resonances in B?B Reactions- Parton Distributions and Their Q2 Dependence- Total Cross Sections of
Abstract: The Whys of Subnuclear Physics- Why Is There Charm, Strangeness, Colour and All That?- Do Mesons Fill SU(3) Nonets?- The Properties of Charmonium and Charm Particles- Recent Results from DASP- New Particles or "Why I Believe in Quarks"- New Particle Production in Hadronic Interactions- Review of Lepton Production in Hadron - Hadron Collisions- Narrow Resonances in B?B Reactions- Parton Distributions and Their Q2 Dependence- Total Cross Sections of Neutrinos and Antineutrinos in BEBC in the Energy Range 20-200 GeV- Measurement of Neutral Current Cross-Sections and Their Energy and y - Dependence- Charged V+A Currents in Left-Right Symmetric Gauge Models- Quark and Lepton Mixing- Quark-Geometrodynamics: A New Approach to Hadrons and Their Interactions- The Uses of Instantons- Can We Make Sense Out of "Quantum Chromodynamics"?- Should We Believe in Quantum Field Theory?- An Exact Relativistic S-Matrix in 1+1 Dimensions: The On-Shell Solution of the Massive Thirring Model and the Quantum Sine-Gordon Equation- Dynamical Symmetries in Nuclear Physics- Symmetries of Quarks and Leptons- The Best Why- Status of the Subnuclear Whys- List of Prizes Awarded, Scholarships, etc- List of Participants
22 citations
TL;DR: In this article, the strangeness transfer distributions for K K production are compatible with predictions obtained from zero-strangeness cluster models, and a comparison with charge-transfer distributions is performed.
20 citations
TL;DR: Using Glauber theory, the authors compute angular distributions for strangeness exchange reactions A Z ( K −, π − ) Λ A Z, which lead to definite states in the hypernucleus ΛAZ.
16 citations
TL;DR: In this paper, the magnetic moments of charmed baryons are calculated based on the four sectors of SU4 which are obtained by picking out three of the four quarks, u, d, s, c in all possible ways.
Abstract: We discuss, from the group-theoretical point of view, a formalism—recently proposed as an useful approach to calculating the magnetic moments of charmed baryons—based on the four sectors ofSU4 which are obtained by picking out three of the four quarks, u, d, s, c in all possible ways. The sectors can be divided into two classes, according to the charge of the removed quark, and aSU3 algebra can be defined for both classes in a suitable way. This leads, among the others, to introduce «generalized hypercharge» and «generalized isospin» operators. Besides the usual strangeness and charm, two new additive quantum numbers «strangenesslike» and «charmlike» are present. With the view of discussing electromagnetic properties, we extend the concept ofU-spin to the sectors different from the «historical» one (u, d, s). Clearly, the interest of this formalism lies in the fact it allows us to reduce many calculations, to be done in the framework ofSU4, to standardSU3 calculations (or even to a straightforward application of well-known formulae of the eightfold way). This is explicitly shown by working out the calculation of the magnetic moments of baryons. The possibility of applying this approach to other physical problems concerning charmed baryons or to quark models with a flavour number higher than four is briefly considered.
5 citations
01 Jan 1979
TL;DR: Weak interactions are known to give rise to the violation of different flavour quantum numbers as discussed by the authors, and the list of the victims include strangeness and charm: it will probably include the quantum number associated new quarks, the alternative being the existence of new unconditionally stable hadrons, and might also include quantum numbers in the lepton sector, such as the muon number.
Abstract: Weak interactions are known to give rise to the violation of different flavour quantum numbers. The list of the victims include strangeness and charm: it will probably include the quantum number associated new quarks — the alternative being the existence of new unconditionally stable hadrons, and it might also include quantum numbers in the lepton sector, such as the muon number.
2 citations
01 Jan 1979
TL;DR: In this paper, the authors discuss the similarities and differences between two different types of particles, the proton and the neutron, and why they appear in groups containing members which are similar and also different.
Abstract: Once upon a time physicists believed that matter was made of protons and electrons. Then the neutron was discovered. There were now two particles, the proton and the neutron, which were very similar, yet they were also different. Now there are many particles classified in groups containing members which are similar and also different. Exactly how are they similar? Exactly how are they different? Why do particles appear in such groups? These are some of the fundamental questions to be explored in these lectures.
01 Sep 1979
TL;DR: In this paper, the consequences of the SU(3)-symmetric and quark structures of weak non-leptonic decays of charmed hadrons are considered.
Abstract: The consequences of the SU(3)-symmetric and quark structures of weak nonleptonic decays of charmed hadrons are considered. The most general consequences of this structure are the relations between the decay amplitudes which follow from the selection rules in T, U, and V spins. A large number of additional relations for the decays of the charmed mesons D/sup +/, D/sup 0/, and F/sup +/ follow from the symmetry of the quark diagrams corresponding to these decays if we neglect all diagrams of the annihilation type. These relations have been obtained for two-particle and three-particle decays. From these in turn we have obtained experimentally verifiable relations between the probabilities of these decays. With use of the existing experimental data on nonleptonic decays of the D/sup +/ and D/sup 0/ mesons we have obtained estimates of the relative probabilities of all remaining decay modes of the same type. High relative probabilities (at the level of several percent) are predicted for the individual decay modes of D and F mesons into three pseudoscalar mesons in a symmetric state and into a vector and a pseudoscalar meson with a change of strangeness ..delta..S=-1, and also comparatively high probabilities (up to 1--2%) of certain modes ofmore » these decays with ..delta..S=0 which are suppressed on the basis of the Cabibbo angle. These results can serve as a guide in the further search for charmed mesons in various reactions.« less
TL;DR: In this paper, it was pointed out that K/sup 0/sub S/K/sup/S/K+S/S+S −S/σ/S/-correlation data can bring important information about the compensation of strangeness of quarks and antiquarks present in the intermediate stages of the process of multiparticle production in hadronic collisions.
Abstract: It is pointed out that K/sup 0//sub S/K/sup 0//sub S/ correlations can bring important information about the compensation of strangeness of quarks and antiquarks present in the intermediate stages of the process of multiparticle production in hadronic collisions. Owing to the short-range character of parton recombinations and resonance decays K/sup 0//sub S/K/sup 0//sub S/ rapidity differences should reflect separations between strange quarks and antiquarks in rapidity. Thus the K/sup 0//sub S/K/sup 0//sub S/-correlation data can discriminate between the two extreme cases of strongly correlated and uncorrelated ss-bar pairs in the intermediate state of the collision. These correlations are relatively easy to study from the experimental point of view.
TL;DR: In this paper, it was pointed out that weak interactions should admix a small parity-violating E1 component into the M1 electromagnetic decay, and weak interactions admixed the parityviolating component to the M 1 electromagnetic decay.
Abstract: It is pointed out that weak interactions should admix a small parity-violating E1 component into the M1 electromagnetic decay ..sigma../sup 0/ ..-->.. ..lambda gamma...
15 Jul 1979
TL;DR: In this paper, the main features of these elementary amplitudes, as revealed through phase shift analyses and meson exchange models, are discussed and the properties of the two body interaction (isospin dependence, Y* and Z* resonance formation, strangeness exchange, etc.) are reflected in reactions induced by kaons in nculei.
Abstract: Kaon beams offer exciting prospects for the study of both nuclear and hypernuclear physics. Experiments on hypernucleus formation via the (−,π−) reaction, as well as elastic and inelastic scattering of K± from nuclei, are already underway. The theoretical analysis of such experiments requires an understanding of the underlying two‐body K±N interaction. We review here the main features of these elementary amplitudes, as revealed through phase shift analyses and meson exchange models. We indicate how the properties of the two body interaction (isospin dependence, Y* and Z* resonance formation, strangeness exchange, etc.) are reflected in reactions induced by kaons in nculei.
01 Jan 1979
TL;DR: In this article, the nuclear strangeness exchange reaction (K¯, π¯) is discussed, and possible reaction mechanisms are reviewed in Section 2, while the spectroscopic ǫ-hypernuclear information derived from observation of strangeness-exchange is discussed in Section 3.
Abstract: In these lectures, the nuclear strangeness exchange reaction (K¯, π¯) is discussed. Possible reaction mechanisms are reviewed in Section 2, while the spectroscopic Ʌ-hypernuclear information derived from observation of strangeness exchange is discussed in Section 3. The more general question of multiply-strange nuclei is introduced in Section 1.