TY - JOUR
T1 - Neutron–antineutron oscillations
T2 - Discrete symmetries and quark operators
AU - Berezhiani, Zurab
AU - Vainshtein, Arkady
N1 - Publisher Copyright:
© 2018 The Author(s)
PY - 2019/1/10
Y1 - 2019/1/10
N2 - We analyze status of C, P and T discrete symmetries in application to neutron–antineutron transitions breaking conservation of baryon charge B by two units. At the level of free particles all these symmetries are preserved. This includes P reflection in spite of the opposite internal parities usually ascribed to neutron and antineutron. Explanation, which goes back to the 1937 papers by E. Majorana and by G. Racah, is based on a definition of parity satisfying P2=−1, instead of P2=1, and ascribing P=i to both, neutron and antineutron. We apply this to C, P and T classification of six-quark operators with |ΔB|=2. It allows to specify operators contributing to neutron–antineutron oscillations. Remaining operators contribute to other |ΔB|=2 processes and, in particular, to nuclei instability. We also show that presence of external magnetic field does not induce any new operator mixing the neutron and antineutron provided that rotational invariance is not broken.
AB - We analyze status of C, P and T discrete symmetries in application to neutron–antineutron transitions breaking conservation of baryon charge B by two units. At the level of free particles all these symmetries are preserved. This includes P reflection in spite of the opposite internal parities usually ascribed to neutron and antineutron. Explanation, which goes back to the 1937 papers by E. Majorana and by G. Racah, is based on a definition of parity satisfying P2=−1, instead of P2=1, and ascribing P=i to both, neutron and antineutron. We apply this to C, P and T classification of six-quark operators with |ΔB|=2. It allows to specify operators contributing to neutron–antineutron oscillations. Remaining operators contribute to other |ΔB|=2 processes and, in particular, to nuclei instability. We also show that presence of external magnetic field does not induce any new operator mixing the neutron and antineutron provided that rotational invariance is not broken.
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U2 - 10.1016/j.physletb.2018.11.014
DO - 10.1016/j.physletb.2018.11.014
M3 - Article
AN - SCOPUS:85057297582
SN - 0370-2693
VL - 788
SP - 58
EP - 64
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
ER -