coulomb excitation at rex-isolde with miniball
DESCRIPTION
Coulomb Excitation at REX-ISOLDE with MINIBALL J. Van de Walle for the MINIBALL- and REX-ISOLDE collaborations. OUTLINE 1/ The Experimental Setup A. (REX-)ISOLDE B. MINIBALL 2/ Some Physics Cases A. Shell Model Interest B. Shape Co-existence. 1/ The Experimental Setup : (REX-)ISOLDE. - PowerPoint PPT PresentationTRANSCRIPT
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Coulomb Excitation at REX-ISOLDE with MINIBALLJ. Van de Walle for the MINIBALL- and REX-ISOLDE collaborations
OUTLINE
1/ The Experimental Setup A. (REX-)ISOLDEB. MINIBALL
2/ Some Physics Cases A. Shell Model InterestB. Shape Co-existence
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1/ The Experimental Setup : (REX-)ISOLDE
1st post-accelerated beam and Coulomb excitation in 2001
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1/ The Experimental Setup : (REX-)ISOLDE
CERN PS Booster1.4 GeV protons
Mass Separation (HRS or GPS)
REX linear accelerator : ≤ 3 MeV/uA/q separator
(A/q < 4.5)
Miniball
EBIS
REXTRAP
Specific time structure of REX-ISOLDE
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1/ The Experimental Setup : (REX-)ISOLDETime Structure
EBIS
REXTRAP
PSB : 1.4 GeV pulsed proton beam
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1/ The Experimental Setup : (REX-)ISOLDETime Structure
EBIS
REXTRAP
Trapping
Charge Breeding
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1/ The Experimental Setup : (REX-)ISOLDETime Structure
EBIS
REXTRAP
Trapping
Charge Breeding
Post Acceleration
Bunched beam : high instantaneous rate ! deadtime …
Good signal/background …
1 shift at REX =
19 min actual measuring time
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1/ The Experimental Setup : (REX-)ISOLDEEfficiency and Count Rates
50 Hz5 Hz
Beam intensity [pps]
Sca
tter
ed p
artic
les
in S
ilico
npe
r 10
mse
c
Bunched beam : high instantaneous rate ! deadtime …
Good signal/background …
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1/ The Experimental Setup : MINIBALLEfficiency and Count Rates
REX efficiency = 6-16 % (TRAP+EBIS+A/q = 10-20% Linac transmission = 60-80%)… depends on mass, A/q, energy … (experience and a bit of luck)
Bunched beam Good signal/background …
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1/ The Experimental Setup : MINIBALLEfficiency and Count Rates
103 particles/second
104 particles/second
105 particles/second
NU
MBE
R O
F G
AMM
A RA
YS
OBS
ERVE
D P
ER S
HIF
T (8
h)
CROSS SECTION [barn]Typically 10% gamma detection efficiency – 2 mg/cm2 –
A target = 120 – REX efficiency 1%
Bunched beam Good signal/background …
REX efficiency = 1 % (nowadays very conservative)
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1/ The Experimental Setup : MINIBALLEfficiency and Count Rates
103 particles/second
104 particles/second
105 particles/second
CROSS SECTION [barn]
1 example : 80Zn : 0.05 b - 3300 pps – 4 days running – 50 counts
NU
MBE
R O
F G
AMM
A RA
YS
OBS
ERVE
D P
ER S
HIF
T (8
h)REX efficiency = 1 % (nowadays very conservative)
Typically 10% gamma detection efficiency – 2 mg/cm2 – A target = 120 – REX efficiency 1%
Bunched beam Good signal/background …
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1/ The Experimental Setup : MINIBALLAb
solu
te E
ffici
ency
[%]
Energy [keV]
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1/ The Experimental Setup : MINIBALL9-gap radiation background
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1/ The Experimental Setup : MINIBALL9-gap radiation background
Coun
ts /
Cry
stal
/ E
BIS
puls
e
g-ray energy [keV]
Coun
ts /
EBI
S pu
lse
Bunched beam Good signal/background …
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1/ The Experimental Setup : MINIBALL9-gap radiation background
g-ray energy [keV]
Coun
ts
61Mn 2.87 MeV/u
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1/ The Experimental Setup : MINIBALL9-gap radiation background
g-ray energy [keV]
Coun
ts
61Mn 2.87 MeV/u
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1/ The Experimental Setup : MINIBALL9-gap radiation background
g-ray energy [keV]
Coun
ts
g-ray energy [keV]
Coun
ts
x 70
61Mn 2.87 MeV/u
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1/ The Experimental Setup : MINIBALLBeam Diagnostics : Z and A determination
E resi
dual (S
i)No protons - Beamgate open
27Al
DE (gas)
E resi
dual (S
i)
With protons - Beamgate open
27Al
27Mg
27Na
DE (gas)
1/ DE (gas) – Erest (Si) Telescope (35deg beamline)
2/ Bragg detector (beamdump Miniball)
17O8+ + 17F8+
17F9+
~ Z
A A
with stripper foil after 9-gap
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1/ The Experimental Setup : MINIBALLDetermination of B(E2) values
Coun
ts
Energy
Relative measurement
Nbeam sbeam(B(E2),Q2+,…) unknown
Ntarget starget(B(E2),…) known
Nbeam
Ntarget
J. Van de Walle et al., submitted to Physical Review C (2008) (74-80Zn coulex)
74Zn coulex
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1/ The Experimental Setup : MINIBALLDetermination of B(E2) values
Coun
ts
Energy
Relative measurement
Nbeam sbeam(B(E2),Q2+,…) unknown
Ntarget starget(B(E2),…) known
!!! possible beam contamination influences this normalization !!!
Nbeam
Ntarget
J. Van de Walle et al., submitted to Physical Review C (2008) (74-80Zn coulex)
74Zn coulex
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2/ Some Physics Cases : Shell Model Interest
30,31,32Mg
67,69,71,73Cu, 68Cu, 70(m)Cu68Ni
74,76,78,80Zn
106,108,110Sn
122,124Cd138,140Xe140,148,150BaZ=28
Z=50
N=4
0Z=82
20
N=5
0
N=8
2
Some physics cases “over the past years” …Evolution of Shell Structure the “island of inversion” : 30,31,32Mg (H. Scheit, P. Reiter et al.)
region around 68-78Ni (Z=28, N=40-50) : 68Ni, 67,69,71,73Ci, 68,70(m)Cu, 74,76,78,80Zn, 61Mn, 61Fe region around 100Sn : 106,108,110Sn, 100,102,104Cd (J. Cederkall, A. Ekstrom et al.)
region around 132Sn : 138,140,142,144Xe, 122,124,126Cd, 140Ba (Th. Kroll, R. Kruecken, Th Behrens et al.)
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Some physics cases “over the past years” …Evolution of Shell Structure the “island of inversion” : 30,31,32Mg (H. Scheit, P. Reiter et al.)
region around 68-78Ni (Z=28, N=40-50) : 68Ni, 67,69,71,73Ci, 68,70(m)Cu, 74,76,78,80Zn, 61Mn, 61Fe region around 100Sn : 106,108,110Sn, 100,102,104Cd (J. Cederkall, A. Ekstrom et al.)
region around 132Sn : 138,140,142,144Xe, 122,124,126Cd, 140Ba (Th. Kroll, R. Kruecken, Th Behrens et al.)
2/ Some Physics Cases : Shell Model Interest
30,31,32Mg
67,69,71,73Cu, 68Cu, 70(m)Cu68Ni
74,76,78,80Zn
106,108,110Sn
122,124Cd138,140Xe140,148,150BaZ=28
Z=50
N=4
0Z=82
20
N=5
0
N=8
2
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region around 68-78Ni (Z=28, N=40-50) : 68Ni, 67,69,71,73Ci, 68,70(m)Cu, 74,76,78,80Zn, 61Mn, 61Fe
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
1f7/2llllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
llllllllll
sd-shell
l
J. Van de Walle et al., submitted to Physical Review C (2008) (74-80Zn coulex)I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008) (67,69,71,73Cu coulex)N. Bree et al., Phys. Rev. C 78, 047301 (2008) (68Ni coulex)I. Stefanescu et al., Physical Review Letters 98, 122701 (2007) (68,70mCu coulex)J. Van de Walle et al., Physical Review Letters 99, 142501 (2007) (74-80Zn coulex)
- Single particle properties (p2p3/2)- Collective properties (ng9/2 filling)
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2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
1f7/2llllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
llllllllll
sd-shell
l
- Single particle properties (2pp3/2)- Collective properties (ng9/2 filling)
Cu isotopes :
PhD Thesis A. De Maesschalck, University Gent (2005)N. Smirnova et al., Phys. Rev. C 69, 044306 (2004).
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2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
1f7/2llllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
llllllllll
sd-shell
l
- Single particle properties (2pp3/2)- Collective properties (ng9/2 filling)
Cu isotopes :
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2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
1f7/2llllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
llllllllll
sd-shell
l
- Single particle properties (2pp3/2)- Collective properties (ng9/2 filling)
Cu isotopes :
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2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
1f7/2llllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
llllllllll
sd-shell
l- Single particle properties (2pp3/2)- Collective properties (ng9/2 filling)
Cu isotopes :
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1f7/2lllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
llllllllll
sd-shell
ll
- Single particle properties (2pp3/2)- Collective properties (ng9/2 filling)
Cu isotopes : 7/2-
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
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5/2-1/2-3/2-
7/2-
Experimental Levels
7/2-
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008) (67,69,71,73Cu coulex)
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5/2-1/2-3/2-
7/2-
Experimental Levels !!!
7/2-
The observed 1/2- doesn’t seem to be behaving as a the theoretical single particle level !
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008) (67,69,71,73Cu coulex)
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The observed 1/2- doesn’t seem to be behaving as a the theoretical single particle level !Whereas 5/2- behaves much more “single particle like …”
5/2-1/2-3/2-
7/2-
Experimental Levels !!!
7/2-
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008) (67,69,71,73Cu coulex)
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5/2-1/2-3/2-
7/2-
Experimental Levels !!!
7/2-
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
B(E2,Jig.s.) [W.u.]
Indeed … first indication is B(E2) …But we need S.F. … !
The observed 1/2- doesn’t seem to be behaving as a the theoretical single particle level !Whereas 5/2- behaves much more “single particle like …”
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008)
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5/2-1/2-3/2-
7/2-
7/2-
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008)
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2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
5/2-1/2-3/2-
7/2-
Nickel Ji=2+
Nickel 2+ 3/2- = 1/2- ,3/2-,5/2-, 7/2-“weak coupling model”
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008)
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5/2-1/2-3/2-
7/2-
Nickel Ji=2+
Nickel 2+ 3/2- = 1/2- ,3/2-,5/2-, 7/2-“weak coupling model”
2/ Some Physics Cases : Shell Model InterestNeutron Rich Cupper isotopes
B(E2,Jig.s.) [W.u.]
I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008)
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2/ Some Physics Cases : Shell Model InterestNeutron Rich Zinc isotopes
- UCx + RILIS + quartz line- 3E3 pps- 4 days running time- 2.87 MeV/u on 2.0 mg/cm2 108Pd- Doppler Correction crucial
J. Van de Walle et al., submitted to Physical Review C (2008)J. Van de Walle et al., Physical Review Letters 99, 142501 (2007)
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2/ Some Physics Cases : Shell Model Interest
J. Van de Walle et al., submitted to Physical Review C (2008)J. Van de Walle et al., Physical Review Letters 99, 142501 (2007)
Global systematics : B(E2) and E(2+)
N=50 systematics : B(E2) and E(2+)
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Increased collectivity for Z>28 and 38<N<44
1f7/2llllllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
sd-shell
llllllllll
ll
2/ Some Physics Cases : Shell Model InterestIron isotopes
Neutron Number
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Neutron Number
Increased collectivity for Z>28 and 38<N<44
ALSO for Z<28, ex. Z=26 (Iron)And 36<N< ??
1f7/2llllll
2p1/2
1f5/22p3/2
sd-shell
28
50
1g9/2
40
p
llllllll
2p1/2
1f5/22p3/2
28
50
1g9/2
40
llll
1f7/2
llllll
n
ll
sd-shell
llllllllll
2/ Some Physics Cases : Shell Model InterestIron isotopes
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Calculations from Caurier et al.EPJA, 15, 145-150 (2002)
pf-shell (KB3G interaction )
2/ Some Physics Cases : Shell Model InterestIron isotopes
Neutron Number
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Calculations from Caurier et al.EPJA, 15, 145-150 (2002)
pf-shell (KB3G interaction )pfgd (52Ca core)
How do the 1g9/2 and possibly 2d5/2 neutron orbitals influence the quadrupole collectivity below Z=28 ?
2/ Some Physics Cases : Shell Model InterestIron isotopes
Neutron Number
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Calculations from Caurier et al.EPJA, 15, 145-150 (2002)
pf-shell (KB3G interaction )pfgd (52Ca core)
How do the 1g9/2 and possibly 2d5/2 neutron orbitals influence the quadrupole collectivity below Z=28 ?
… BUT
2/ Some Physics Cases : Shell Model InterestIron isotopes
Neutron Number
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Calculations from Caurier et al.EPJA, 15, 145-150 (2002)
pf-shell (KB3G interaction )pfgd (52Ca core)
How do the 1g9/2 and possibly 2d5/2 neutron orbitals influence the quadrupole collectivity below Z=28 ?
… BUT no Fe beam @ ISOLDE … First test with 61Mn in-trap decay to 61Fe
2/ Some Physics Cases : Shell Model InterestIron isotopes
Neutron Number
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2/ Some Physics Cases : Shell Model Interest61Mn,61Fe
Trapping for 30 ms
Charge Breeding for 28 ms
Coulomb excitation 61Mn
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2/ Some Physics Cases : Shell Model Interest61Mn,61Fe
Coulomb excitation 61Mn
Energy [keV]
Co
un
ts
109Ag 312 keV 415 keV
61Mn
61Mn
X 4
0
- Charge breeding time = Trapping time = 28 ms- Measuring time = 3.5h- On average 1x105 pps
J.J. Valiente-Dobon et al., PRC 78, 024302 (2008)
157 keV : 33(2) W.u. (preliminary)
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2/ Some Physics Cases : Shell Model Interest
Trapping for 200 ms (up to 900 ms)
Charge Breeding for 28 ms
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2/ Some Physics Cases : Shell Model Interest
Energy [keV]
Co
un
ts
61Mn
No 61Fe coulex ???
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2/ Some Physics Cases : Shell Model Interest
Trapping for 200 ms (up to 900 ms)
Charge Breeding for 298 ms
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2/ Some Physics Cases : Shell Model Interest
Energy [keV]
61Mn
61Fe
Co
un
ts
207 keV : 19(4) W.u. (preliminary)
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2/ Some Physics Cases : Shape Co-existence
Some physics case “over the past years” …Shape Co-existence
70Se and 96Sr (A.M. Hurst et al. PRL 98, 072501 (2007), E. Clement et al, 2007))
202,204Rn : A. Robinson, this session 182,184,186,188Hg : A. Petts, this session
70Se
Z=28
Z=50
N=4
0Z=82
20
N=5
0
N=8
296Sr
182,184,186,188Hg
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation
Accurate Lifetime measurement needed (non-trivial for rare isotopes) Low statistics in Coulomb excitation
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation
Accurate Lifetime measurement needed (non-trivial for rare isotopes) Low statistics in Coulomb excitation
Ex. : the case of 70Se …
A.M. Hurst et al. PRL 98, 072501 (2007) J. Ljungvall et al. PRL 100, 102502 (2008)
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation
Accurate Lifetime measurement needed (non-trivial for rare isotopes) Low statistics in Coulomb excitation
Ex. : the case of 70Se …
A.M. Hurst et al. PRL 98, 072501 (2007) J. Ljungvall et al. PRL 100, 102502 (2008)
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation
Accurate Lifetime measurement needed (non-trivial for rare isotopes) Low statistics in Coulomb excitation - From the sensitivity to diagonal matrix element in Coulex ( Q2+= 0.7479 <2+||M(E2)||2+>)
No external input needed High statistics needed
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LABO
RATO
RY a
ngle
simulation
2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Diff
Cro
ss S
ectio
n (b
/sra
d)Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation- From the sensitivity to diagonal matrix element in Coulex ( Q2+= 0.7479 <2+||M(E2)||2+>)
Center-of-mass angle
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LABO
RATO
RY a
ngle
simulation
2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Diff
Cro
ss S
ectio
n (b
/sra
d)Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation- From the sensitivity to diagonal matrix element in Coulex ( Q2+= 0.7479 <2+||M(E2)||2+>)
Center-of-mass angle
0+
2+
4+
0+2+
4+
0
413
1005
824881
1208
413
592
413 keV (188Hg)
592 keV (188Hg) +
558 keV (114Cd)
Highest statistics Coulex ever @ REX
( > 60.000 counts 2 +→0 + )
N. Bree and A. Petts
Energy [keV]
coun
ts
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LABO
RATO
RY a
ngle
simulation
2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Diff
Cro
ss S
ectio
n (b
/sra
d)Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation- From the sensitivity to diagonal matrix element in Coulex ( Q2+= 0.7479 <2+||M(E2)||2+>)
Center-of-mass angleLABORATORY angle (strip number)
Experiment
simulation
Ener
gy [M
eV]
Ener
gy [M
eV]
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Diff
Cro
ss S
ectio
n (b
/sra
d)Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation- From the sensitivity to diagonal matrix element in Coulex ( Q2+= 0.7479 <2+||M(E2)||2+>)
Center-of-mass angle
413 keV (188Hg)
592 keV (188Hg) +
558 keV (114Cd)
Q2+ = +1.5 b (oblate)Q2+ = 0 b (spherical)
PRELIMINARY
Analysis by N. Bree (KU Leuven)
0+
2+
4+
0+2+
4+
0
413
1005
824881
1208
413
592
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2/ Some Physics Cases : Shape Co-existenceThe Quadrupole Moment
Determining the sign and magnitude of the spectroscopic Quadrupole Moment … How ?- Combining lifetime measurements and Coulomb excitation- From the sensitivity to diagonal matrix element in Coulex ( Q2+= 0.7479 <2+||M(E2)||2+>)
- Coulomb excitation on two different targets Choice of targets is difficult
Statistics in beam excitation on both targets
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Conclusions
- 5 successfull experiments this year.many more to come next year ...
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Conclusions
- 5 successfull coulex experiments this year : Mn, Rn, Hg, Cd, Cu ...- physics results have been published and are being prepared for publication
(... not necessarily complete !)Coulomb excitation of neutron-rich beams at REX-ISOLDEH. Scheit et al., European Physical Journal A 25, 397-402 (2005)"Safe" Coulomb Excitation of MgO. Niedermaier et al., Physical Review Letters 94, 172501 (2005)The neutron-rich Mg isotopes: first results from MINIBALL at REX-ISOLDE O. Niedermaier, et al., Nuclear Physics A 752, 273-278 (2005)First use of post-accelerated isomeric beams for Coulomb excitation studies of odd-odd nuclei around N=40G. Georgiev et al., International Journal of Modern Physics E 15, 1505 (2006)Coulomb Excitation of 88Kr and 92Kr in inverse kinematicsD. Mucher et al., Progress in Particle and Nuclear Physics 59, 361-363 (2007)Measurement of the Sign of the Spectroscopic Quadrupole Moment for the 2+1 State in 70Se : No Evidence for Oblate ShapeA. Hurst et al., Physical Review Letters 98, 072501 (2007)Coulomb excitation of the odd-odd nuclei 68,70Cu; first use of post-accelerated isomeric beamsI. Stefanescu et al., Physical Review Letters 98, 122701 (2007)Sub-Barrier Coulomb Excitation of 110Sn and its Implications for the 100Sn Shell ClosureJ. Cederkall et al., Physical Review Letters 98, 172501 (2007)Coulomb Excitation of Neutron Rich Zn isotopes : First Observation of the 2+1 State in 80Zn J. Van de Walle et al., Physical Review Letters 99, 142501 (2007)Interplay between single-particle and collective effects in the odd-A Cu isotopes beyond N=40I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008)0+gs2+1 transition strengths in 106Sn and 108SnA. Ekström et al., Phys. Rev. Lett. 101, 012502 (2008)Coulomb excitation of 68Ni40 at “safe” energiesN. Bree et al., Phys. Rev. C 78, 047301 (2008)Low Energy Coulomb Excitation of Neutron Rich Zinc isotopes J. Van de Walle et al., submitted to Physical Review C (2008)In-Trap Decay of 61Mn and Coulomb Excitation of 61Mn and 61FeJ. Van de Walle et al., in preparation for Eur. Phys. J. A (2008)...
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Conclusions
- 5 successfull experiments this year.- physics results have been published and are being prepared for publication
- Some online references :www.miniball.york.ac.ukisolde.web.cern.ch/ISOLDE
- Tests with stable beams (end nov. or 2009)- In-trap decay with REXTRAP under investigation- Transfer reactions using MINIBALL starting now (see talk Wednesday, V. Bildstein and K. Wimmer)