From mischke Wed Oct 1 14:06:59 MDT 1997 Received: (from mischke@localhost) by p25hp.lanl.gov (8.7.6/8.7.1) id OAA08529 for cooper@p25hp.lanl.gov; Wed, 1 Oct 1997 14:06:58 -0600 (MDT) From: Dick Mischke Message-Id: <199710012006.OAA08529@p25hp.lanl.gov> Subject: edm letter To: cooper@p25hp.lanl.gov Date: Wed, 01 Oct 1997 14:06:58 MDT X-Mailer: Elm [revision: 212.2] Status: RO To: shelley@umphys.physics.umanitoba.ca sergnivanov@lnpi.spb.su james@jsbach.harvard.edu hal@pn.scphys.kyoto-u.ac.jp haseyama@pnl.scphys.kyoto-u.ac.jp cjones@krl.caltech.edu phkiang@ccvax.sinica.edu.tw matsuda@pn.scphys.kyoto-u.ac.jp sakai@yap.nucl.ap.titech.ac.jp seidel@physics.brown.edu rstoner@cfa.harvard.edu takala@lanl.gov phteng@ccvax.sinica.edu.tw thomas@scipp.ucsc.edu walker@uwnuc0.physics.wisc.edu rwalsworth@cfa.harvard.edu hogan_gary@lanl.gov marek@lanl.gov sandberg@lanl.gov gpb@t13.lanl.gov sbrice@lanl.gov vieira@lanl.gov cy@lanl.gov, pdbarnes@lanl.gov, glg@lanl.gov, tjb@lanl.gov, bowman@lanl.gov, cbowman@lanl.gov, rhill@lanl.gov, ahime@lanl.gov, lamore@lanl.gov, penttila@lanl.gov, seestrom@lanl.gov, john@p25hp.lanl.gov, aptp@lanl.gov, boissevain@lanl.gov, mcooper@lanl.gov, mbjohnson@lanl.gov, louis@lanl.gov, mischke@lanl.gov, cmorris@lanl.gov, tupa@lanl.gov, xu_nu@lanl.gov, ccw@lanl.gov, espy@lanl.gov, erf@lanl.gov, dschmidt@lanl.gov, rcs@lanl.gov, av@p25hp.lanl.gov, herczeg@lanl.gov, tgoldman@lanl.gov, gbw@lanl.gov,, emil@pion.lanl.gov, bangert@p25hp.lanl.gov, jdonahue@lanl.gov, rkraus@lanl.gov, peng@lanl.gov Date: Thu, 25 Sep 1997 13:44:27 MDT X-Mailer: Elm [revision: 212.2] Status: RO /mega1/users/cooper/text/edm.collab September 25, 1997 Dear Colleagues, It has been 6 months since we held the "Workshop on a New Experiment to Measure the Neutron Electric Dipole Moment." The silence actually indicates that we have been moderately busy in advancing the experiment. We want to take this opportunity to bring everyone up to date regarding the state of the project and to propose an organizational meeting for the collaboration. Since the workshop, our experimental efforts at Los Alamos have been focused by available funding on three goals: 1) Determining the distribution of 3He in a bath of 0.5-K 4He, 2) Determining the polarization lifetime of 3He in a test cell, 3) Evaluating the application of SQUID's to the experiment. We have built up a simple device for measuring dilute 3He in gaseous 4He and observed the predictable uniform distribution with a collimated, cold neutron beam. We have shown that the technique will work to very dilute solutions and observed 1.5 photoelectrons per phototube in that geometry. We have also performed a Monte-Carlo simulation to demonstrate a factor of two improvement in the UCN density if the cell is surrounted by a reflector. Currently, we are trying to move toward cryogenic apparatuses. A laboratory is being outfitted with equipment. The first goals are to operate our dilution refrigerator and to design a test cell. In parallel, a test cryostat and associated hardware are under construction to measure the base noise level in a SQUID with a superconducting pickup loop attached. A critical step toward a real experiment is getting Los Alamos National Laboratory to back us. The neutron beams from the spallation source are produced by LANSCE Division. Recently, its director, John Browne, called for a review of all fundamental neutron experiments. He is hoping the results of the review will be a very strong endorsement of the projects, allowing him to easily justify using some of his resources, e.g. beam lines, toward these experiments. For the review, we are preparing a letter-of-intent to perform the EDM measurement. The first draft is being sent to you as postscript files along with this note. The deadline for final submission is September 30. If you have comments before September 29, we would be happy to take them into consideration. Our appologies for the short notice, but as you can see, we are on a tight schedule. We plan to submit the written document with only two names, Martin Cooper and Steve Lamoreaux, as contacts. At the review to be held on November 20-21, we hope to lay out more information on the collaboration. There are several more Los Alamos staff working on the project. As a result of the workshop, we have received a very positive letter from Mike Pendlebury at Sussex. John Doyle of Harvard and Bob Golub the HMI are already working on issues relating to the full EDM experiment. If the workshop or the letter of intent is sufficient for groups to commit to the collaboration, we would be happy to announce all members at the time of the review. In order to inaugurate the collaboration, we would like to hold an organizational meeting in Los Alamos. If the week before the review, e.g. November 18-19, were chosen, a great deal more could be said about the collaboration at the review. If you would like to attend, please send us dates when you could not come, and we will try to select dates that minimize conflicts even if they are not those above. As this meeting will likely set the tone for the collaboration, it is important, but attendence is not mandatory for joining the experiment either before or after it occurs. Of course, we hope you will decide favorably at some time. A more detailed agenda will be prepared, but possible topics for discussion are listed below. Feel free to suggest other subjects. This meeting will not be a conference, but a working group to hammer out plans for the future. A) Conceptual design of the experiment 1) The components of the experiment a) The cold neutron guide b) The 4He cryogenics c) The measuring cell d) Light transmission out of the cell e) Magnetic shields (penitrations) f) Uniform magnetic field g) RF magnetic field h) 3He polarization and transport system i) 3He-4He purification and handling system 2) Team to make a preliminary engineering layout B) The proposal 1) Its contents 2) For whom is it being prepared? C) Definition of the experimental development plan 1) Issues need experimental work 2) Issues that need calculations 3) Issues that need Monte-Carlo simulation 4) Who wants to work on what? D) The schedule 1) What are the constraints? 2) What is reasonable? E) Costs 1) A first guess 2) Method of estimating the costs 3) Coordination of costing F) Funding 1) What are the potential sources? 2) Yearly profile G) Collaboration organization 1) What is needed for this size project? a) Scientific council? b) Construction council? c) Project manager? 2) Memoranda of understanding? 3) Selection of spokespersons for some period 4) Collaboration meetings: frequency and location 5) Manpower availability of each group over time Warm regards, Martin Cooper mcooper@lanl.gov Geoff Greene glg@lanl.gov Steve Lamoreaux lamore@lanl.gov