New experimental limit on the electric dipole moment of the neutron

The latest neutron electric dipole moment (EDM) experiment has been collect ing data at the Institut Laue-Langevin (ILL), Grenoble, since 1996. It uses an atomic-mercury magnetometer to compensate for the magnetic field fluctu ations that were the principal source of systematic errors in previous expe riments. The first results, in combination with the previous ILL measuremen t, yield a possible range of values of (-7.0 < d(n) < 5.0) x 10(-26)e cm (9 0% C.L.). This may be interpreted as an upper limit on the absolute value o f the neutron EDM of \d(n)\ < 6.3 x 10(-26)e cm (90% C.L.).