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Where next (with HDU)?
• Q-value
• mass.
• excitation energies.
• Angular distributions of recoils
• l-value
• spectroscopic information
Transfer reaction toolboxReaction Study Equipment
(d,p)(d,n)(d,t)
neutron particleproton particleneutron hole
silicon array (S-ORRUBA, SIDAR)neutron array (VANDLE)silicon array (S-ORRUBA, SIDAR)
(3He,d)(3He,n)(3He,t)
proton particle2-proton transfercharge-exchange
silicon array (S-ORRUBA, SIDAR)neutron array (VANDLE)silicon array (S-ORRUBA, SIDAR)+ gas jet or implanted targets
(9Be,8Be)(13C,12C)
neutron particlestates with higher l
charged particle (HI Ball) + γ detection (CLARION/GRETINA)
(t,p)(10Be,8Be)
2-neutron transfer tritium targetsilicon array (S-ORRUBA, SIDAR)
Where next …• Beyond 132Sn
– 134Sn, 136Te etc..– Proton states with (d,n).– 2-neutron transfer (t,p)? (10Be,8Be)?
• Beyond N=50– 84Ge, 86Se etc..
• New regions– 70Ni region.
• both neutron and proton single-particle states.
– batch mode beams of 44Ti, 56Ni, 59Fe.
data for several channels (elastic, inelastic…)
range of energies (low versus high)
more theory
What is needed for a successful nuclear reaction program? (the theorist’s wish)
Optical potentials are an essential input to calculations
should we not be working toward a CH89_ri and BG_ri?- nucleon elastic scattering of rare isotopes
at least (p,p) then theory for (n,n) (?)- heavy ion elastic scattering of rare isotopes
Other things that can help:elasticelastic breakupinelastic breakup(p,d)
reaction models need to incorporate the structure:should we be using standard radius and diffuseness?
by probing different energies we get a glimpse into different parts of the structure we are interested
by probing different energies we can test whether our simplified structure assumptions are correct
need accurate description of the reaction• better control over uncertainties in inputs• improved understanding of reaction dynamics• keeping contact with underlying many body structure
should we be using Hartree Fock densities, radii, etc for unstable nuclei? (often unable to even predict the correct bound state…)
134134Te(d,p)Te(d,p)135135TeTe
PRELIMINARYPRELIMINARY
~1 MeV (p1/2)
~1.8 MeV (f5/2 ?)
g.s. (f7/2)
~0.66 MeV (p3/2)
Q value (MeV)
Co
un
ts
Position-dependent gainsEnergy-dependent lengthsand high thresholds
Super ORRUBASuper ORRUBA
• 512 channel system ordered ~2008• 512 channel system implemented June 2010.• 2056 channel system implemented June 2011.
•Funding received Sept. 2009.•Detectors ordered Nov. 2009.•Design done by June 2010.•Prototype arrive Dec. 2010.•Full order June 2011.•Full array June 2012.
TIARA PerformanceTIARA Performance
Only core signals from EXOGAM clovers,
limiting Doppler correction to 65 keV
broadening
pp
TIARA PerformanceTIARA Performance
Only core signals from EXOGAM clovers,
limiting Doppler correction to 65 keV
broadening
pp
Measured quantitiesFlight time: Tflight=Tcyc
Position: zEnergy: Elab
Measured quantitiesFlight time: Tflight=Tcyc
Position: zEnergy: Elab
Principle of operation
Derived quantitiesPart. ID: m/qEnergy: Ecm
Angle: cm
Derived quantitiesPart. ID: m/qEnergy: Ecm
Angle: cm
/zqemVVmmE2
mV2zqe
2
1arccos
z2
qeVmVEE
T2
e
q
m
cm2cm
2lab
cmcm
cm2cm2
1labcm
flight
B
B
B
Β
Particle Tcyc (ns)p 34.2
3He2+ 51.4d, 68.5
t 102.7
B=2T
136Xe(d,p) online spectrum – B.Kay, Nov. 2009
Preliminary
(d,n) and -delayed neutrons with VANDLE
• Optimize efficiency for 60° to 180° for ejected neutrons.
• 150 keV > En > 15 MeV
• 1.5 meter flight-path for large bars cover central angles.
• Shorter path for small bars cover lower energy neutrons at back
angles.
• Intend to measure 25Al(d,n)• Astrophysically important 26Al possibly created by: 25Al (p,γ)→26Si(β+) →26Al
• rp-process waiting point nuclei• 56Ni(d,n)