Fundamental Interactions Physics

1
Fundamental InteractionsPhysics
InstrumentationConclusions

• Conveners
• P. Mueller, J. ClarkG. Savard, N. Scielzo

2
Short Term

• Fully utilize low energy beams from CARIBU for
  mass measurements, laser spectroscopic studies
  and decay experiments. Ideally, the space
  available for low energy experiments at CARIBU
  should be expanded to fully exploit these
  possibilities (NA6).

3
Initial focus of measurements with the CPT at
CARIBU

• First measurements
• 132Sn and neighbors
• 130Cd and neighbors

• Future measurements
• go as neutron-rich as possible

4
Moving the CPT to CARIBU
CARIBU
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Laser Lab Layout _at_ CARIBU
Cf-252 source 80 mCi -gt 1Ci
Gas catcher
High-resolution mass separator dm/m gt 1/20000
RF Cooler Buncher
starting in fall 2010
6
Beta-delayed neutron emission
Novel approach determine neutron energies and
branching ratios by detecting beta particles and
recoil ions that emerge from ion trap Provide
reliable data for r-process nucleosynthesis,
nuclear structure, nuclear reactor performance,
modeling of environments where fission fragments
are produced
Example
Q 4.9 MeV t1/2 0.378 sec Pn 9
MCP ion detector

• 1-mm3 trapped-ion sample and 1-ns timing
  resolution of detectors determines neutron
  momentum/energy to 1 from time-of-flight of
  recoiling daughter ion
• intrinsic efficiency for MCP detectors can be
  100
• many fission fragments available from the
  newly-developed CARIBU facility (an intense
  source of fission-fragment beams) at ANL

7
Short Term

• Utilize ATLAS intensity upgrade (Phase I) for
  improved beta decay correlation experiments and
  weak interaction studies by increased production
  rate of light isotopes close to stability (e.g.
  6He, 8Li, 14O, 18Ne ) (FI4). Phase II upgrade, in
  particular the recoil separator, would
  significantly improve production and separation
  of these isotopes.

8
Beta-neutrino correlation in 8Li
Beta-neutrino correlation measurement takes
advantage of 1 mm3 trapped ion sample and
position and energy resolution of double-sided
silicon strip detectors to precisely reconstruct
momentum vectors of all emitted particles
(including neutrino!)
Neutrino momentum/energy can be determined from
b- and recoiling 8Be momentum/energy b-
momentum/energy measured from DSSD and plastic
scintillator detector 8Be momentum/energy
determined from a particle break-up with no
recoil, a particles would have same energy and
would be back-to-back. With recoil, energy
difference can be up to 730 keV and the angle can
deviate by as much as 70
Low mass of 8Li and Q 13 MeV lead to large
recoil energies of 12 keV which makes the
correlation easier to measure. Other b-n
correlation measurements have had to deal with
recoil energies of only 0.2-1.4 keV.
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Beta-Decay Study with Laser Trapped 6He

• 6He trapping rate 1?104 s-1,
• 2?105 coincidence events in 15 min da
  0.008
• 1 week da/a 0.1

• 6He yields
• ATLAS 1?107 s-1
• CENPA 1?109 s-1
• SARAF / SPIRAL2 1?1012 s-1

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Medium Term

• Improve isotope separation and overall
  transmission of the ion transfer line after the
  gas catcher into the triangle room. This would
  enable mass measurements closer to the proton
  drip line (65As) once the CPT is moved back to
  its previous location (NA2). This upgrade also
  would improve correlation studies and decay
  experiments possible at that location (FI4).

11
Moving the CPT to CARIBU
CARIBU
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Long Term

• Add gas catcher and low-energy beam-line behind
  recoil separator for studies of very proton rich
  isotopes (e.g. around 100Sn, requires Phase II).
  Provide experimental area to accommodate
  low-energy beam experiments, e.g., in the ATSCAT
  area.
• Support high precision measurements of basic
  nuclear properties of isotopes close to stability
  (on the proton rich side) to enable future high
  precision measurement far off stability at FRIB,
  e.g., measurements of T2 superallowed beta
  decays.

13
Moving the CPT to CARIBU
CARIBU
RecoilSeparator
14
T2 nuclei present an alternative way to check
Isospin breaking corrections
Bhattacharya et al., PRC 77, 065503 (2008)
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Long Term

• Find a stronger source for 225Ra for improved EDM
  experiment that will be truly statistics limited
  (FI9).

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Search for EDM of 225Ra

• Advantages
• Large enhancement
• EDM(Ra) / EDM(Hg) 200 2000
• Efficient use of 225Ra atoms
• High electric field (gt 100 kV/cm)
• Long coherence times ( 100 s)
• Negligible v x E systematic effect