Display the Experiment Proposals for S788

Experiment: S788

Nuclear and Atomic Physics with the CPT Spectrometer

by the The CPT Collaboration group

Closed
Spokespersons:
K.S. Sharma (University of Manitoba)

Original Proposal for EEC meeting 199612S

Table of Contents

Detailed Information

Proposal/Report S788_199612SP.pdf (1.56 MB)

Beam Shift Summary

12-hr ShiftsBeam Line / channelPolarized Primary BeamPriority
New Beam Requests
 182 4A/TISOL No
Committee Recommendations
  No N/A

In the event that the TASCC facility at Chalk River is closed, the collaboration wishes to bring the Canadian Penning Trap (CPT) mass spectrometer to TRILJMF to be installed, initially on TISOL and later at ISAC. This combination of ISAC plus the CPT will produce a unique world-class facility. Extending the range of available mass measurements for unstable isotopes is directly related to the study of nuclear mass formulae and is relevant to astrophysical problems such as the r-process. Measurements of Q-values for superallowed β emitters are important in determining the Vud mixing element of the CKM matrix and for tests of CVC.

In view of the likely time scales for the move to TRIUMF, the Committee recommends that the apparatus should not be installed at TISOL but rather should be moved directly to ISAC. The apparatus would be commissioned using stable isotopes and a separate ion source would be required for these measurements, which are of interest in their own right.

RECOMMENDATION: Shift allocation and priority will be made at an appropriate time after the review of ISAC experiments.


Membership

K.S. Sharma University of Manitoba Professor 70 % Spokesperson
X. Feng University of Manitoba Research Associate 100 %  
G. Savard Chalk River Laboratories Research Scientist 80 %  
J. Crawford McGill University Professor 50 %  
J. Lee McGill University Professor 50 %  
S. Gulick McGill University Research Associate 50 %  
E. Hagberg Chalk River Laboratories Research Scientist 30 %  
F. Buchinger McGill University Professor 30 %  
R.B. Moore McGill University Professor 30 %  
B. Barber University of Manitoba Professor 10 %  
J.C. Hardy Chalk River Laboratories Research Scientist 10 %  
V. Koslowsky Chalk River Laboratories Research Scientist 10 %  

Basic Information

Date Submitted
2009-01-28 15:59:17
Date Experiment Ready
1997-04-01
Projected Completion Date
1998-04-30
Summary *

The Canadian Penning Trap (CPT) Mass Spectrometer Facility, currently under construction at the TASCC facility, is a powerful tool for the study of nuclear science through the precise determination of the atomic masses of both stable and unstable nuclides. The instrument is capable of performing measurements with an accuracy of δM/M =10-8 to 10-9 = 10 and extends the capabilities of such instruments to nearly any element for the first time. As a result of budget cuts at AECL, it will be necessary to move the CPT to a location that can supply short-lived radioactivities for the measurement program. The currently operating TISOL facility and the new ISAC facility in the near future would present an ideal location, within Canada, for this instrument. The proposed measurement program has three immediate goals:

1. Precise atomic mass measurements among stable isotopes aimed at improving and adding to the backbone of well known masses and improving some specific masses related to double-beta decay, bound state beta decay and atomic mass standards. The spectrometer will be used off-line for these measurements.

2. Precise atomic mass measurements among unstable isotopes which will extend our knowledge of atomic masses into new regions and provide a solid foundation for the development of better theories of nuclear mass.

3. Precise Q-values of superallowed 0+ → 0+ β emitters:

Precision studies of 0+ → 0+ superallowed β decays provide the necessary data to test stringently the CVC hypothesis. They will also provide a value for the weak vector coupling constant and the VUd quark mixing element of the Cabibbo-Kobayashi Maskawa (CKM) matrix. The determination of this element is crucial for unitarity tests of the CKM matrix, and the search for physics beyond the Standard Model.

At present, studies of superallowed 0+ → 0+ beta decays have confirmed the CVC hypothesis at the 4 x 10-4 level. The yalue for the Vud element of the CKM matrix, deduced from 0+ → 0+ studies, is the most precise one available. When used in a first row test of CKM unitarity, the tests fail at the two standard deviation level.

One of the necessary experimental quantities required for these tests are precise QEC values. Presently nine superallowed emitters are known with adequate precision. Penning trap mass measurements can improve the data set in three ways. In order of increasing difficulty they are:

a) improve the precision of the most poorly known cases

b) add new cases outside the range of existing ones

c) probe the magnitude of atomic effects in precise reaction Q-value studies.

In addition to this work experiments are also planned for the future on laser spectroscopy on trapped atoms and measurements of beta-decay asymmetry measurements on trapped ions.

Plain Text Summary *
Primary Beam Line
TISOL experimental area for the first three years moving to the ISAC low energy experimental area when ready
Primary Beam and Target
500 MeV protons ≈ 1μA intensity, unpolarized. Targets and ion-sources as required by TISOL or ISAC to produce the activities with the requested yields.
Secondary Channel
Secondary Beam

TISOL/ISAC equipped with ECR, surface ionization and plasma (FEBIAD type) ion sources producing low energy, mass separated, radioactive beam of:

A Cs isotopes over as wide a range as possible 106 atoms/sec 25 shifts

B Hg isotopes (A=178-207) 106 atoms/sec 50 shifts

C Sm, Eu, Gd, and TB isotopes 106 atoms/sec 50 shifts

D 14O, 26mAl, 38mK 106 atoms/sec 12 shifts

E 62Ga, 66As, 70Br, 30S 5x107 25 shifts

F 10C, 14O, 26mAl 106 atoms/sec 20 shifts

at ≈ 20 to 66 keV energy with a spot size of 5mm x 5mm and delivered to the CPT injection system.

TRIUMF Support (Resources Needed)
Operation of the TRIUMF Facility, including TISOL (ISAC in the future) with ECR, surface ionization and plasma (FEBIAD type) ion-sources, pool electronics, mechanical and electrical engineering, LN2, LHe, water, power, compressed air and other support for the installation and operation of the CPT mass spectrometer (including temperature and humidity controlled enclosures for lasers and traps) at TISOL initially and moving later to the ISAC facility when ready, technical support for the CPT facility, expenses for the transport and installationof the CPTMS initially at TISOL and subsequently at ISAC.
Other Funding

NSERC MFA grant for the CPT mass spectrometer facility (held until 1998)

NSERC project grant for the modification of the CPT mass spectrometer (applied for October 1996)

NSERC operating and team grants held by participants.

Muon Justification
Safety Issues

The procedures required by the TRIUMF Safety Group in the normal operation of the TISOL (and ISAC) will be followed.

An enclosure is needed for the operation of the lasers used by the CPT mass spectrometer.

Proposals and Progress Reports

199612S (Original Proposal)