f. m. nunes nscl, michigan state university
DESCRIPTION
Recent developments in the study of halo breakup. F. M. Nunes NSCL, Michigan State University. In collaboration with: Neil Summers (MSU) and Ian Thompson (Surrey). halo06. structure versus reactions. data = reaction x structure. - PowerPoint PPT PresentationTRANSCRIPT
F. M. NunesNSCL, Michigan State University
halo06
Recent developments in the study of halo breakup
In collaboration with: Neil Summers (MSU) and Ian Thompson (Surrey)
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structure versus reactions
data = reaction x structure
Usually not this simple: reaction and structure are entangled!
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Importance
of breakup
breakup and driplines
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11Be(p,p’)10Be+n
[Shrivastava et al, PLB 596 (2004) 54][Shrivastava et al, PLB 596 (2004) 54]
low energy continuum experiments
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23O(Pb,Pb)22O+n+g[Nociforo et al, PLB 605 (2005) 79][Nociforo et al, PLB 605 (2005) 79]
9Be(17C, 16C )X
[Maddalena et al., PRC63(01)024613]
low energy continuum experiments
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breakup with CDCC: three body reaction
core
valence
target
rR
•Projectile treated as 2-body system•3-body Hamiltonian for reaction
vcrvc
vcvTcTR
VTh
hVVTH
0),(),(
0)()(
kljkljvc
nnnnvc
rkrkh
rrh
l = core-valence relative angular momentumj = projectile total angular momentum
is single particle/cluster wavefunction defined by potential Vvc
binding energy for bound states
resonances and scattering phaseshifts for continuum
fixed by
fix VcT and VvT from elasticscattering
Summers @ NSCL2004
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continuum discretization
i
i
k
klji
ilji dkrkkw
Nr
1
),()(2
)(,
•Discretize continuum into bins•average wavefuntion over a bin with weight wi(k)
exc
g.s.
s1/2 p1/2 p3/2 d3/2 d5/2 f5/2 f7/2
Evc
0
20
wi(k) chosen so that thebin wavefunctions are realand normalized correctly using
i
i
k
kii dkkwN
1
2|)(|
•label the quantum numbers
for each bin by i,lj
Summers @ NSCL2004
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CDCC equations
1)()()()( ''
' RuRVRuERVT JJJJLR
)()(),(
)ˆ()(),()ˆ()()( '''
vTvTcTcT
JMLJMLJ
RVRVRrV
RYrRrVRYrRV
•Solve set of radial coupled equations
•Where the coupling potential from state to state ’ is
and the cluster target potentials include both Coulomb and Nuclear parts
•We have N coupled channels, each labeled by the set of quantum numbers
)( Ljli
Summers @ NSCL2004
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• F.M. Nunes and I.J. Thompson, Phys.Rev.C59, 2652 (1999).• B. Davids, et al., Phys.Rev.C 63, 065806 (2001).• J.A. Tostevin, F.M. Nunes, and I.J. Thompson, Phys.Rev.C 63, 024617 (2001).• J. Mortimer, I.J. Thompson, and J.A. Tostevin, Phys.Rev.C 65, 064619 (2002).• A. Moro et al., Phys. Rev. C 67, 047602 (2003).• T. Egami, et al., Phys.Rev.C 70, 047604 (2004).
CDCC results for breakup
8B breakup into p+7Be
•K. Rusek and K.W. Kemper, Phys.Rev.C 61, 034608 (2000).•T. Matsumoto, et al., Phys.Rev.C 70, 061601(R) (2004).•K. Ogata et al., Phys. Rev. C 73, 051602 (2006).
6He breakup into nn+4He
6Li breakup into d+4He•N. Keeley and K. Rusek, Phys. Letts B 375, 9 (1996).•K. Rusek and K.W. Kemper, Phys.Rev.C 61, 034608 (2000).•C. Signorini et al., Phys. Rev. C 67, 044607 (2003).
11Be breakup into n+10Be• J.A. Tostevin et al., Phys. Rev. C 66, 024607 (2002).• M. Takashina, et al., Phys.Rev.C 67, 037601 (2003).• A. Shrivastava et al., Phys. Lett. B596, 54 (2004).
• N.C. Summers and F.M. Nunes, Phys. Rev.C 70, 011602(R) (2004).
7Be breakup into 3He+4He
15C breakup into n+14C•J.A. Tostevin et al., Phys. Rev. C 66, 024607 (2002).
•H.B. Jeppesen et al., Nucl. Phys. A 748, 374 (2005).
9Li(d,p)10Li(continuum)
•Obertelli et al., Phys. Letts B 633, 33 (2006)
26Ne(d,p)27Ne(continuum)
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mistake?
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core excitation: eXtended CDCC
[Summers, Nunes and Thompson, PRC 73 (2006) 031603R][Summers, Nunes and Thompson, PRC 73 (2006) 031603R]
JIjs ;,
r
I
lj
Standard Approximations
Single particle projectile
Spectator core XCDCC includes
Coupled configuration of projectile
Dynamical excitation of core
0+
n
10Be
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breakup of 11Be
JIjs ;,
r
I
lj0+0+
0+
0+2+
2+
projectile fully coupled
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breakup of 11Be
JIjs ;,
r
I
lj
0+2+
0+
0+0+
2+
Dynamical excitation
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coupled channel model for 11Be
JIjs ;,
r
I
lj
[Nunes, Thompson and Tostevin, NPA 703 (2002) [Nunes, Thompson and Tostevin, NPA 703 (2002) 593]593]
coupled channel equation (i=l,j,I)
deformation of the core introduced via Rws
core matrix elements = rotational model
)(),( corevcrproj hrVTH
pJIjsla rYrr )](])([[)(),(
)()()()( ''
' rrVrerVT pppp Ja
aa
Jaa
Jaaa
Jaa
lr
)](1[)( 202 rYRrR ws
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continuum discretization
a
p
k
k
annanni
inJ JIjslrdkrkkw
Nr
i
i
P;,),(|,),()(
2)(
1
:
•Discretize coupled channel continuum into bins
quantum numbers
for each bin by n l,j,I
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computational problem
)()()()( ''
' RRVRERVT TTTT JJJJLR
TvtvtctctTJ JRVRVJRV ;')(),(;)('
•We have a very very large number of coupling potentials to calculate
•Second order coupled differential equation (enhanced numerov method)
parallelized for each channel J
parallelized
•Our present limit on the cluster is memory per node!
•Memory ~ NR.NC2
•Dimension: NR=400-5000 radial steps NC=50-1800 channels
NJ=30-200 J channels
•Code in F90 + MPI
•Time ~ NR.NC3 .NJ
(L,Jp,Jt,J,i,n)
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applications of XCDCC
p(11Be,10Be+n+)p @ E~60 MeV/u
breakup on a protons
elastic+inelastic+transfer+breakup
breakup on a heavy target at intermediate energies208Pb(11Be,10Be+n+) 208Pb @ E~40-60 MeV/u
breakup on a light target9Be(11Be,10Be+n+) 9Be @ E~60 MeV/u
knockout
inelastic+breakup
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computation details for HPC-cluster
NC
under the approximation of no spin of the neutron
Breakup on 9Be @ E=60 MeV/A
NR=5000 NC=500 NJ=100 NCPUS=4 walltime=5.5 d mem=65Gb
Breakup on a heavy target @ E=40 MeV/A
NR=400 NC=1800 NJ=30 NCPUS=16 walltime=4 d mem=120Gb
Breakup on a protons @ E=40 MeV/A
[Summers, Nunes and Thompson, PRC[Summers, Nunes and Thompson, PRC7474, 014606 (2006)], 014606 (2006)]
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breakup of 11Be on 9Be
Comparison with other models
measurement at MSU: neutron was not detectedIncludes stripping as well as breakup
9Be(11Be,10Be)X @ E=60 MeV/A
[Summers, Nunes and Thompson, PRC 73 (2006) 031603R][Summers, Nunes and Thompson, PRC 73 (2006) 031603R]
CDCC
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breakup of 11Be
Stripping is not sensitive to deformation
[Batham, Thompson and Tostevin, PRC[Batham, Thompson and Tostevin, PRC7171 064608 064608 (2005)](2005)]
• Eikonal model including dynamical rotational excitations of 16C core
• Inclusive cross section of rotational states of 16C
• Assumed 17C(3/2+) [1d5/22+] ground state - pure single particle state with excited 2+ core
• Enhanced breakup cross section due to deformed 16C+Target interaction
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breakup of 11Be
Stripping cross section taken from eikonal calculations (J.A. Tostevin 2005)
9Be(11Be,10Be)X @ E=60 MeV/A
XCDCC breakup
Data: Aumann Data: Aumann et al.et al., PRL84, 35 (2000), PRL84, 35 (2000)
[Summers, Nunes and Thompson, PRC 73 (2006) 031603R][Summers, Nunes and Thompson, PRC 73 (2006) 031603R]
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elastic 11Be+p
data: Lapoux et al, GANIL
data: Shrivastava et al., Phys. Lett. B 596 (2004) 54.
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breakup 11Be on p
data: Shrivastava et al., Phys. Lett. B 596 (2004) 54.
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inelastic 11Be+Pb
Data: Pain Data: Pain et al.et al., GANIL, GANIL
GANILGANIL
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inelastic 11Be+Pb
Data: Pain Data: Pain et al.et al., GANIL, GANIL
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• XCDCC provides an important step forward for understanding reactions with exotic beams
• can be applied to a wide range of energies• includes nuclear and Coulomb on equal footing
• consistent core excitation is also now possible• results for 11Be show that is has predictable power
still some discrepancies to understand…
Conclusions
Experimentalists: Need less integrated data!!
Theorists: Need better structure model for projectile!!
Experimentalists: elastic! elastic! elastic!
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Thanks
Only possible due to: Neil Summers (Rutgers)