The Storage Ring Electric Dipole Moment Collaboration Home Page

Hadronic Electric Dipole Moments: probe the Deuteron EDM in a storage ring

The Storage Ring EDM collaboration is working on a new method capable of reaching a sensitivity of 10^-29 e-cm for the deuteron bare nucleus. The deuteron EDM (dEDM) proposal as submitted to the BNL PAC in April 2008 is given here: 2008 deuteron_EDM_proposal. The neutron equivalent sensitivity of the dEDM and of other nuclei is given in neutron equivalent sensitivity along with the physics reach of the project.

The method has great sensitivity to, among others, Quark Chromo-EDM

---- For papers of interest to EDM go to EDM papers.

---- Papers and reference material per deuteron EDM sub-system (restricted).

---- EDM related papers and other material you may find useful (In flux, these files may be deleted or replaced by new ones without warning).

---- EDM Internal Notes (restricted).

---- Storage Ring EDM Collaboration photos.

---- EDM Teleconferences (restricted).

---- EDM collaboration meetings (restricted).

---- Recent talks related to EDM (restricted).

---- Deuteron Proposal 2004 (restricted).

---- The talks at the EDM Workshop and Collaboration meeting at LNF, Frascati, Rome-Italy, Oct 3-10, 2005 can be reached at Frascati Workshop.

The proposal to the Brookhaven Program Advisory Committee submitted in August 2004 can be found in deuteron_EDM_proposal. The deuteron EDM experiment at 10^{-27} e cm is 10 to 100 times better than current EDM limits in terms of sensitivity to quark and gluon EDM, and the QCD theta parameter. It probes CP-violation at a range predicted by speculative theories beyond the standard model. The deuteron and neutron EDM searches are complementary and combined together they will provide severe constraint to the CP-violation sources. If CP-violation is found at that level it could shed light on the Baryon/anti-Baryon asymmetry mystery of the universe.

The electric dipole moments (EDM) of fundamental particles are excellent probes of physics beyond the standard model (SM), e.g. SUSY, since they allow for values within experimental reach whereas the SM predictions are several orders below them. The collaboration aims at improving the sensitivity on the deuteron and muon EDMs by several orders of magnitude using a new method: "EDMs in storage rings", hence the name: "Storage Ring EDM Collaboration". This method is based on the highly innovative approach of canceling the g-2 precession in the horizontal plane by using a radial electric field. This method can be applied to charged particles with small anomalous magnetic moments like the deuteron and muon.

A large part of the "EDMs in storage rings" method is built on our experience with spin and beam dynamics in a storage ring after many years working on the muon g-2 experiment. Papers on the new method can be found in [ muon_EDM, deuteron_EDM]. Many speculative theories beyond the SM predict EDM values well within the sensitivity of both experiments. See, e.g., Enhanced Electric Dipole Moment of the Muon...   by Babu et al., PRL 85, 5064 (2000), and Probing CP Violation with the Deuteron Electric Dipole Moment , hep-ph/0402023 by By Oleg Lebedev (DESY), Keith A. Olive (Minnesota U., Theor. Phys. Inst.), Maxim Pospelov (Victoria U.), and Adam Ritz (CERN) which claims that at 3x10^{-27} e cm the deuteron EDM experiment will be 10 to 100 times better than the best current EDM experimental limit.  

Muon EDM:

---- J-PARC Letter of Intent: Search for a Permanent Muon Electric Dipole Moment at the 10^{-24} e cm Level.  in postscript format (4.6MB). The same file in PDF   (0.85MB) or in gzipped   (1.2MB). The figures reproduce best in ps and ps.gz. Authors: Muon EDM collaboration

---- For the edm-l@lists.bnl.gov e-mail archive go to e-mail archive (Restricted. To access it you need to enter your e-mail address used in EDM-l@lists.bnl.gov and your assigned password).

---- Inclinometer Home Page: Tiltmeter Home Page A very sensitive tiltmeter development at BNL for the EDM experiment. Its sensitivity is projected to be better than 1nrad.

Physics of the muon EDM Experiment: We are proposing a new method to carry out a dedicated search for a permanent electric dipole moment (EDM) of the muon with a sensitivity at a level of 10^{-24} e cm. The experimental design exploits the strong motional electric field sensed by relativistic particles in a magnetic storage ring. As a key feature, a novel technique has been invented in which the g-2 precession is compensated with radial electric field. Muon Spin Precession without Electric Field Compensation and with Electric Field Compensation. The EDM signature is the time dependent muon spin precession vertically: Vertical Muon Spin Precession, observed with the following Detection Method of the Muon Spin Direction.

The standard model of particle physics is a very successful theoretical framework, which describes all confirmed observations to date. However, the model leaves important questions concerning the physical nature of observed processes unexplained, although it provides an accurate description of them. Among the not yet understood phenomena are the reasons for parity violation, the particle masses, the violation of the CP symmetry. CP violation is the only known mechanism that could explain the matter antimatter asymmetry found in the universe. In order to obtain a deeper insight, speculative models have been suggested which often are connected to observable deviations from standard theory predictions, particularly violations of assumed symmetries or yet unknown properties of particles. The spectrum of these theories includes super symmetry (SUSY), left-right symmetry, multi Higgs scenarios and many other important approaches. For more details go to Physics of EDM. For a short description of the Muon EDM experimental concept go to Short Paper on EDM.

---- Workshop held at Cape Cod on Lepton Moments. Lepton Moments, 19 - 22 June 2006.

---- EDM Workshop and Collaboration meeting at LNF, Frascati, Rome-Italy. Frascati Workshop, Oct 3-10, 2005.

---- Workshop held at Cape Cod on Lepton Moments. Lepton Moments, 9 - 12 June 2003.

---- Workshop held at BNL on the Future of the EDM Measurements of the Electron, Muon and Nucleon. EDM Workshop May 14 and 15, 2001.

For the muon g-2 WEB page at BNL go to Muon g-2 page at BNL.

The Boston g-2 WEB page: BU g-2 page.

This page is maintained by Yannis Semertzidis. Tel. at BNL: (631) 344-3881

Last update 23 April 2008