Chronology of Milestone Events in Particle Physics - DAVIES 1955
Chronology of Milestone Events in Particle Physics

DAVIES 1955

G-Stack collaboration; Davies, J.H. et al.
On the Masses and Modes of Decay of Heavy Mesons Produced by Cosmic Radiation
Nuovo Cim. 2 (1955) 1063;

Summary
A large emulsion stack, exposed at high altitude, has been used to study the decay-modes of K-particles which produce a single charged secondary. The 5 decay modes, K, , , K and ' have been recognized from the nature and energy of the charged secondary. The masses of the parent particles of the two-body decay modes, K and , found from the mean range of the charged secondary are (976 7) me and (969 3) me respectively. Independent values derived from measurements of the scattering of the secondary track near the decay point are (954 17) and (972 3) me respectively. The reliability of these mass values is discussed. An examination of the relative frequency of the decay modes in these experimental conditions indicates that the K- and - modes constitute respectively about 67% and 20% of all the K-particle decays: the K, and ' modes being present to about 9%, 3% and 1% respectively.

Accelerator COSM Detectors EMUL

Related references
See also
K. Gottstein et al., Phil. Mag. 42 (1951) 708;
W. F. Fry, G. R. White, Phys. Rev. 90 (1953) 207;
O. Heinz, Phys. Rev. 94 (1954) 1728;
W. H. Barkas and L. Yong, Phys. Rev. 98 (1955) 605;
F. Anderson, G. Lawlor, and T. E. Nevin, Nuovo Cim. 2 (1955) 608;
L. Voyvodic and E. Pickup, Phys. Rev. 85 (1952) 91;
F. M. Smith, W. Birnbaum, and W. H. Barkas, Phys. Rev. 91 (1953) 765;
G. Baroni et al., preprint CERN BS/9 (1954);
R. H. Dalitz, Proc. of the Rochester Conf. (1955);
R. W. Birge et al., Mimeografed report of the Piza Conference (1955) 151;
S. C. Fung, N. Mohler, A. Pevsner, and D. Ritson, Mimeografed report of the Piza Conference (1955) 201;
G. Puppi, Nuovo Cim. Suppl. 11 (1954) 438;
Analyse data from
R. H. W. Johnston and C. O'Ceallaigh, Phil. Mag. 46 (1955) 393;
C. Dahanayake, P. E. Francois, and Y. Fujimoto, Phil. Mag. 45 (1954) 1219;
M. W. Friedlander, D. Keefe, M. G. K. Menon, and I. van Rossum, Phil. Mag. 45 (1954) 1043;
J. Cruesard, M. F. Kaplon, J. Klarmann, and J. H. Noon, Phys. Rev. 93 (1954) 253;
A. Pais, Phys. Rev. 86 (1952) 663;
R. H. Dalitz, Proc. Roy. Soc. 66 (1953) 710;
R. Armenteros et al., Nuovo Cim. 1 (1955) 915;
B. P. Gregory et al., Nuovo Cim. 11 (1954) 292;
A. L. Hodson et al., Phys. Rev. 96 (1954) 1089;
M. Baldo et al., Nuovo Cim. 1 (1955) 1180;
H. S. Bridge et al., Nuovo Cim. 1 (1955) 874;
M. G. K. Menon and C. O'Ceallaigh, Proc. Roy. Soc. A221 (1954) 292;
R. H. Brown et al., Nature 163 (1949) 82;
C. O'Ceallaigh, Phil. Mag. 42 (1951) 1032;

Reactions
  K+ + o
  K
  K+ +
  K+ + 2o
  K o
  K+ e+ 2neutral
  K e 2neutral
  K+ + 2neutral
  K 2neutral

Particles studied
  K+ mass, pw
  K mass, pw

Record comments
Measurements of charged kaon decay branching fractions.
    
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