ISSN:
1749-6632
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Natural Sciences in General
Notes:
The origin of the CP violation discovered in the K0 system 25 years ago, remains uncertain.1,2 Assuming that CPT is conserved (where T is time reversal symmetry), a CP violating force can create a permanent electric dipole moment (EDM) on elementary particles such as the quarks and leptons, as well as on nondegenerate collections of particles such as the neutron, an atomic nucleus, or even atoms.3 Progressively decreasing experimental upper limits on the EDM of the bare neutron have helped narrow the range of models that attempt to explain CP violation (see ref. 4 for a recent review of the theory). In the standard model, the neutron EDM arises in second order of the weak interaction and is expected to be very small, of order 10−32e. cm. Most extensions to the standard model, however, allow the neutron EDM to be generated in first order of the weak interaction, making the expected value near 10−26 cm, close to the present experimental limit, or even larger.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1749-6632.1989.tb50605.x
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