3:30 PM, Friday, October 2, 2009
Dr. Wolfgang Korsch
"The Quest for a
Permanent Electric Dipole Moment''
In the nuclear sector the most stringent limit on a permanent EDM was recently achieved at the University of Washington with a value of 3.1x10-29 e-cm for Hg-199. We are in the process of developing a new EDM search based on laser-cooled and trapped Ra-225 atoms. Due to octupole deformation of the nucleus, Ra-225 is expected to be significantly more sensitive to T-violating interactions than Hg-199.
The experimental sensivity to the neutron EDM has been improved by eight orders of magnitude over the last six decades. At present, the best limit of 2.9x10-26 e-cm was achieved at the Institut Laue-Langevin (ILL) using ultra-cold neutrons in a magnetic trap. A new experiment with the goal to improve this limit by possibly two orders of magnitude is under construction at the Spallation Neutron Source (SNS) in Oak Ridge. A dense target of ultra-cold neutrons, ``stored in a box,'' in combination with a novel detection technique will be used to accomplish this goal.
The present status of these experiments and the technology to achieve these objectives will be discussed.
Refreshments will be served in CP 179 at 3:15 PM