Chronology of Milestone Events in Particle Physics - GLASSER 1961
Chronology of Milestone Events in Particle Physics


Glasser, R.G.; Seeman, N.; Stiller, B.;
Mean Lifetime of the Neutral Pion
Phys. Rev. 123 (1961) 1014;

An estimate of the mean lifetime of the o meson has been obtained from an experiment employing a direct time-of-flight technique first attempted by Harris et al. in 1957. This method is based upon the observation in nuclear emulsion of the decay of the K+2 meson (K+ + o) and the subsequent decay of the o via the Dalitz mode, o e+ e . In the present experiment we were able to utilize a new fine-grained emulsion (Ilford L.4) that yielded markedly improved resolution. The availability of the separated K+ beam from the Bevatron at Berkeley permitted detection and measurement of 76 Dalitz decays. We obtain, for the mean lifetime of the o, = (1.9 0.5) x 10-16 sec.

Accelerator LBL Detectors EMUL

Related references
See also
A. V. Tollestrup, S. Berman, R. Gomes, and M. A. Ruderman, in Proc. of the 1960 Ann. Int. Conf. of the High Energy Physics at Rochester (1960) 27;
H. Primakoff, Phys. Rev. 81 (1951) 899;
B. M. Anand, Proc. Roy. Soc. A220 (1953) 183;
G. A. Snow and M. M. Shapiro, Rev. of Mod. Phys. 33 (1961) 231;
Analyse data from
R. P. Haddock, A. Abashian, K. M. Crowe, and J. B. Czirr, Phys. Rev. Lett. 3 (1959) 478;
R. F. Blackie, A. Engler, and J. H. Mulvey, Phys. Rev. Lett. 5 (1960) 384;
G. Harris, J. Orear, and S. Taylor, Phys. Rev. 106 (1957) 327;
V. Glasser and R. A. Ferrell, Phys. Rev. 121 (1961) 886;
W. K. H. Panofsky, R. L. Aamodt, and J. Hadley, Phys. Rev. 81 (1951) 565;
W. Chinowsky and J. Steinberger, Phys. Rev. 93 (1954) 586;
J. Steinberger, W. K. H. Panofsky, and J. Steller, Phys. Rev. 78 (1950) 802;
R. Bjorklund et al., Phys. Rev. 77 (1950) 213;
M. Schein, J. Fainberg, D. M. Haskin, and R. G. Glasser, Phys. Rev. 91 (1953) 973;

Experiment comments
28600 K+ endings in emulsion, 75 cases of Dalitz decays, one event of double Dalitz decay.

  K+ + o
  o 2e 2e+
  o e e+

Particles studied
  o w

Record comments
First conclusive measurements of the o lifetime.
  New Comments List of Comments