Eur. Phys. J. A 11, 1-4 (2001)
Short Note
Nonmesonic decay of the
-hyperon
in hypernuclei produced by p + Au collisions
B. Kamys1, P. Kulessa2, H. Ohm2, K. Pysz3, Z. Rudy1, H. Ströher2 and W. Cassing4
1 M. Smoluchowski Institute of Physics, Jagellonian University, PL-30059 Cracow, Poland
2 Institut für Kernphysik, Forschungszentrum Jülich, D-52425 Jülich, Germany
3 H. Niewodniczanski Institute of Nuclear Physics, PL-31342 Cracow, Poland
4 Institut für Theoretische Physik, Justus Liebig Universität Giessen, D-35392 Giessen, Germany
ufrudy@cyf-kr.edu.pl
(Received: 20 November 2000 / Revised version: 12 April 2001 Communicated by Th. Walcher )
Abstract
The lifetime of the -hyperon for the nonmesonic decay
N
NN
has been determined by a measurement at COSY Jülich of the delayed fission
of heavy
hypernuclei produced in proton-Au collisions at
GeV.
It is found that heavy hypernuclei
with mass numbers
and atomic numbers
fission with a lifetime
(stat.)
(syst.) ps.
This value together with the results obtained for other heavy hypernuclei
in previous investigations indicates -on the confidence level of 0.9-
a violation of the phenomenological
rule
for the
N
NN transitions as known from
the weak mesonic decays of kaons and hyperons.
13.30.-a - Decays of baryons.
13.75.Ev - Hyperon-nucleon interaction.
21.80 - Hypernuclei.
25.80.Pw - Hyperon-induced reactions.
© Società Italiana di Fisica, Springer-Verlag 2001