# New Particle Spectroscopy and Decays

Chapter

## Abstract

In the year since the last meeting in this series, great progress has been made in the spectroscopy of the new particles and their decays. Much of this progress is either directly the result of experiment or at least has been very much stimulated by the astonishing results presented to us one after another by our experimental colleagues. In one way, what has happened is exemplified by the contrast between what was known about the 4-GeV region in e^{+}e^{−} → hadrons a year ago^{1} (Figure 1) and data^{2} which were shown this morning (Figure 2).

## Keywords

Hadronic Decay Charged Multiplicity Heavy Lepton Direct Decay Final State Hadron
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

## Preview

Unable to display preview. Download preview PDF.

## References

- 1.J. E. Augustin et al., Phys. Rev. Letters 34, 764 (1975).CrossRefGoogle Scholar
- 2.W. Tanenbaum, invited talk at this conference; see also J. Siegrist et al., SLAC-PUB-1717, 1976 (unpublished).Google Scholar
- 3.M. L. Perl et al., Phys. Rev. Letters 35, 1489 (1975).CrossRefGoogle Scholar
- 4.F. J. Gilman, in Theories and Experiments in High Energy Physics, A. Perlmutter and S. Widmayer, eds. ( Plenum Press, New York, 1975 ), p. 29.Google Scholar
- 5.B. J. Bjorken and S. L. Glashow, Phys. Letters 11, 255 (1964).CrossRefGoogle Scholar
- 6.S. L. Glashow, J. Illiopoulos, and L. Maiani, Phys. Rev. D2, 1285 (1970).Google Scholar
- 7.G. Zweig, CERN preprints TH. 401 and TH. 412, 1964 (unpublished); also J. Iizuka, Suppi, Prog. Theor. Phys. 37-38, 21 (1966).Google Scholar
- 8.H. Oberlack, invited talk at this conference.Google Scholar
- 9.For a summary and references on the C=+ states found at DESY and SLAC, see the talks of B. H. Wiik and G. J. Feldman, respectively, in Proceedings of the 1975 International Symposium on Lepton and Photon Interactions at High Energies, W. T. Kirk, editor (Stanford Linear Accelerator Center, Stanford, 1976), pps. 69 and 39.Google Scholar
- 10.M. Bander et al., UC-Irvine preprint No. 75–54, 1975 (unpublished). C. Rosenzwieg, University of Pittsburgh preprint PITT-158, 1975 (unpublished).Google Scholar
- 11.Recall that the SPEAR scan for narrow resonances possesses a sensitivity which is expressed in terms of the area (in say nb-MeV) under the possible resonance peak which would lead to a detectable state. This area is proportional to the e
^{+}e^{−}decay width 26 F.J. G I LMAN 2divided by M_{R}.Google Scholar - 12.The full scan up to - 7.6 GeV and references are found in R. F. Schwitters, Proceedings of the 1975 International Symposium on Lepton and Photon Interactions at High Energy, W. T. Kirk, editor ( Stanford Linear Accelerator Center, Stanford, 1976 ), p. 5.Google Scholar
- 13.A. M. Boyarski et al., Phys. Rev. Letters 34, 1357 (1975).CrossRefGoogle Scholar
- 14.B. Jean-Marie et al., Phys. Rev. Letters 36, 291 (1976).CrossRefGoogle Scholar
- 15.F. J. Gilman, invited talk in High Energy Physics and Nuclear Structure-1975, D. E. Nagle, R. L. Burman, B. G. Storms, A. S. Goldhaber, and C. K. Hargrave, eds. (American Institute of Physics, New York, 1975), AIP Conference Proceedings No. 26, p. 331.Google Scholar
- 16.See the photon spectra in A. D. Liberman, Proceedings of the 1975 International Symposium on Lepton and Photon Interactions at High Energy, W. T. Kirk, editor (Stanford Linear Accelerator Center, Stanford, 1976 ), P. 55.Google Scholar
- 17.Here K*EK*(890), a member of the nonet of vector mesons, while K**-K*(1420), a member of the nonet of tensor mesons.Google Scholar
- 18.The experimental situation is reviewed in G. S. Abrams, Proceedings of the 1975 International Symposium on Lepton and Photon Interactions at High Energy, W. T. Kirk, editor (Stanford Linear Accelerator Center, Stanford, 1976 ), p. 25.Google Scholar
- 19.S. Rudaz, Cornell preprint CLNS-324, 1975 (unpublished). Recall also that 14–7rp is known (REf. 14) to be overwhelmingly “direct” rather than electromagnetic in origin.Google Scholar
- 20.W. Tanenbaum et al., SLAC-PUB-1969, 1975 (unpublished).Google Scholar
- 21.In the usual spirit of vector dominance for a process on the photon-mass-shell, one uses the y4 coupling as measured on the ti-mass-shell in -e+e. Similarly, for 1,1» vector dominance, one employs tU’+e e.Google Scholar
- 22.The contributions from the “light” p,w, and are negligible. Note that the additional heavy vector meson contributions which were omitted would have to cancel the calculated contributions from the 1 or tr almost completely to reproduce the experimental data.Google Scholar
- 23.SLAC-Wisconsin collaboration (private communication).Google Scholar
- 24.Technically, in the charmonium picture there is an additional dependence on the strong interaction (gluon-quark) coupling constant for the “direct” hadronic decays. However, as this change is only logarithmic, the coupling only changes slightly between 3.1 and 3.7 GeV.Google Scholar
- 25.See A. Liberman, Ref. 16, and G. J. Feldman, invited talk at the Palermo Conference, June 23–28, 1975 and SLAC-PUB-162)+, 1975 (unpublished).Google Scholar
- 26.H. Harari, Weizmann Institute preprint WIS-75/39, 1975 (unpublished). See also in this connection C. Rosenweig, University of Pittsburgh preprint PITT-156, 1975 (unpublished) and Chan Hong-Mo et al., Rutherford Laboratory preprints RL-75–177 and RL-75–192, 1975 (unpublished).Google Scholar
- 27.See, for example, T. Appelquist and H. D. Politzer, Phys. Rev. Letters 34, 43 (1975).Google Scholar
- 28.G. J. Feldman, invited talk at the Irvine Conference, December, 1975 (unpublished).Google Scholar
- 29.A. Benvenuti et al., Phys. Rev. Letters 34, 419 (1975).CrossRefGoogle Scholar
- 30.B. Barish in Proceedings of La Physique du Neutrino a Haute Energie ( Ecole Polytechnique, Paris, 1975 ), p. 131.Google Scholar
- 31.Gargamelle collaboration, CERN preprint, 1975 (unpublished), and H. Deden et al., Phys. Letters 58B, 361 (1975).Google Scholar
- 32.J. von Krogh et al., University of Wisconsin preprint, 1975 (unpublished).Google Scholar
- 33.A. M. Boyarski et al., Phys. Rev. Letters 35, 196 (1975).CrossRefGoogle Scholar
- 34.See R. F. Schwitters, Ref. 12.Google Scholar
- 35.This comes from calculating the largest possible multiplicity due to a “bump” and assuming it all arises from the weak decays of two charmed particles. Since “ordinary” pions, etas, etc. will generally be produced in the same event as charmed particles, this number is certainly an upper limit, given our assumptions.Google Scholar
- 36.Inasmuch as any change in the total multiplicity is small, and a small change in the charged multiplicity on a bump in R cannot be ruled out yet, the increase in neutrals must be considered as very tentative.Google Scholar
- 37.See, for example, S. Nussinov, Institute for Advanced Study preprint C002220–51+, 1975 (unpublished).Google Scholar

## Copyright information

© Plenum Press, New York 1976