Decay <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mfrac><mrow><mi>J</mi></mrow><mrow><mi>ψ</mi></mrow></mfrac><mo>→</mo><mn>3</mn><mi>γ</mi></math></span> and a Search for the <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>η</mi></mrow><mrow><mi>c</mi></mrow></msub></mrow></math></span>

R. Partridge; C. Peck; F. Porter; W. Kollman; M. Richardson; K. Strauch; K. Wacker; D. Aschman; T. Burnett; M. Cavalli-Sforza; D. Coyne; H. Sadrozinski; E. Bloom; F. Bulos; R. Chestnut; J. Gaiser; G. Godfrey; C. Kiesling; M. Oreglia; R. Hofstadter; I. Kirkbride; H. Kolanoski; A. Liberman; J. O'Reilly; J. Tompkins

doi:10.1103/PhysRevLett.44.712

Decay $\frac{J}{ψ} \to 3 γ$ and a Search for the $η_{c}$

R. Partridge, C. Peck, F. Porter, W. Kollman, M. Richardson, K. Strauch, K. Wacker, D. Aschman, T. Burnett, M. Cavalli-Sforza, D. Coyne, H. Sadrozinski, E. Bloom, F. Bulos, R. Chestnut, J. Gaiser, G. Godfrey, C. Kiesling, M. Oreglia, R. Hofstadter, I. Kirkbride, H. Kolanoski, A. Liberman, J. O'Reilly, and J. Tompkins

Phys. Rev. Lett. 44, 712 – Published 17 March 1980

Abstract

The decay $\frac{J}{ψ}$ into $3 γ$ final states has been studied. No evidence is found for the existence of the $X (2.83)$ or any heavy narrow state (e.g., the $η_{c}$ ) decaying into two photons. Upper limits are given on the branching ratio $\frac{J}{ψ} \to η_{c}$ , $η_{c} \to 2 γ$ for $η_{c}$ masses in the 2.7-3.0-GeV region. In addition, the branching ratios $\frac{J}{ψ \to γ η}$ , $γ η^{'}$ are measured. It is found that the $η^{'}$ branching ratio is higher than previously reported.

Received 17 December 1979

DOI:https://doi.org/10.1103/PhysRevLett.44.712

Authors & Affiliations

R. Partridge, C. Peck, and F. Porter

Physics Department, California Institute of Technology, Pasadena, California 91125

W. Kollman^*, M. Richardson, K. Strauch, and K. Wacker

Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138

D. Aschman, T. Burnett^†, M. Cavalli-Sforza, D. Coyne, and H. Sadrozinski

Physics Department, Princeton University, Princeton, New Jersey 08540

E. Bloom, F. Bulos, R. Chestnut, J. Gaiser, G. Godfrey, C. Kiesling, and M. Oreglia

Stanford Linear Accelerator Center, Stanford University, Stanford, California 94305

R. Hofstadter, I. Kirkbride, H. Kolanoski, A. Liberman^‡, J. O'Reilly, and J. Tompkins

Physics Department and High Energy Physics Laboratory, Stanford University, Stanford, California 94305

^*Present address: Wentorfer Strasse 149, 2050 Hamburg, West Germany.
^†Permanent address: Physics Department, University of Washington, Seattle, Washington 98195.
^‡Schlumberger-Doll Research Center, Ridgefield, Connecticut 06877.