E. Fiori, G. Georgiev, R. Lozeva : CSNSM, orsay L. Gaudefroy : CEA, Bruyères -Le- Chatel
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Exploring life-time of low- lying states in neutron-rich nuclei towards 78Ni with the plunger technique at GANIL B. Mouginot (IPN-Orsay) E. Fiori, G. Georgiev, R. Lozeva : CSNSM, orsay L. Gaudefroy : CEA, Bruyères-Le-Chatel M. Amthor, M.Assie, G.Burgunder, L. Caceres, E. Clément, G. De France, F. de Oliveira, A. Dijon, S. Grevy, M. Harakeh, C. Stodel, J.C. Thomas, P. Ujic : GANIL, Caen C. Borcea, A. Buta M. Catalin, F. Negoita, D. Pantelica, F. Rotaru : IFIN-HH, Bucharest P. Bednarczyk, M. Kmiecik, A. MAJ, S. Myalski : IFJ PAN, Krakovi L. Coquard, O. Moeller : IKP, Darmstadt A. Dewald, C. Fransen, G. Friessner, M. Hackstein, T. Pissula, W. Rother, : IKP, Universität zu köln F. Azaiez, S. Franchoo, F. Ibrahim, I. Matea, B. MOUGINOT, M. Niikura, L. Perrot, J. A. Scarpaci, I. Stefan, D. Verney : IPN, Orsay G. de Angelis : LNL INFN, Legnaro A. Burger : University of Oslo
description
Exploring life-time of low-lying states in neutron-rich nuclei towards 78Ni with the plunger technique at GANIL B. Mouginot (IPN-Orsay). E. Fiori, G. Georgiev, R. Lozeva : CSNSM, orsay L. Gaudefroy : CEA, Bruyères -Le- Chatel - PowerPoint PPT Presentation
Transcript of E. Fiori, G. Georgiev, R. Lozeva : CSNSM, orsay L. Gaudefroy : CEA, Bruyères -Le- Chatel
Exploring life-time of low-lying states in neutron-rich nuclei towards 78Ni with the plunger technique at GANIL
B. Mouginot (IPN-Orsay)E. Fiori, G. Georgiev, R. Lozeva : CSNSM, orsayL. Gaudefroy : CEA, Bruyères-Le-ChatelM. Amthor, M.Assie, G.Burgunder, L. Caceres, E. Clément, G. De France, F. de Oliveira, A. Dijon, S. Grevy, M. Harakeh, C. Stodel, J.C. Thomas, P. Ujic : GANIL, CaenC. Borcea, A. Buta M. Catalin, F. Negoita, D. Pantelica, F. Rotaru : IFIN-HH, BucharestP. Bednarczyk, M. Kmiecik, A. MAJ, S. Myalski : IFJ PAN, Krakovi L. Coquard, O. Moeller : IKP, Darmstadt A. Dewald, C. Fransen, G. Friessner, M. Hackstein, T. Pissula, W. Rother, : IKP, Universität zu köln F. Azaiez, S. Franchoo, F. Ibrahim, I. Matea, B. MOUGINOT, M. Niikura, L. Perrot, J. A. Scarpaci, I. Stefan, D. Verney : IPN, OrsayG. de Angelis : LNL INFN, Legnaro A. Burger : University of Oslo
Se84
As83
Ge82
Ga81
Zn80
Cu79
Ni78
Zn78Zn76
Ni74 Ni76Ni72Ni70Ni68Ni66
Cu65
Zn66 Zn67 Zn68 Zn70
Ge70 Ge72 Ge73
Se74
Ge74
Ga69 Ga71
Se76 Se77 Se78
As75
Se80 Se82
Ni64
Ge76
50
28
Zn74Zn72
Ge78 Ge80
50
28
f5/2
p3/2
p1/2
g9/2
d5/2
s1/2
d3/2
g7/2
f7/2
g9/2
p1/2
h11/2
74Zn
EURORIB 2010
Present Knowledge :
J Van de Walle et alPhysical Review Letters 99, 142501 (2007)Physical Review C 79, 014309 (2009)
O Perru et al Physical Review Letters 96, 232501 (2006)
B.MOUGINOT, IPNOEURORIB 2010
2+ energy (from Z=26 to 34)
B(E2) strength (from Z=28 to 34)
N.J. Stone, Atomic Data and Nuclear Data Tables 90 (2005) 75-176
Evolution of the neutron orbital energy as fonction of the deformation parameter
Proton core polarisation
E(2+) flatness
Region of possible deformation
74Zn Fermi Level
K quantum number: 1/2 3/2 5/2 7/2 9/2
Enhance collectivity with Z number
Oblate Prolate
How the Q/ will evolve in more neutron rich Zn isotopes? In this presentation I will focus on 74Zn
Known Quadrupole Moment :
B.MOUGINOT, IPNOEURORIB 2010
)32)(1(
)1(2.
2
0
jJ
JJKQQ s
J
)16.01(5
3 200
ZRQ
N.J. Stone, Atomic Data and Nuclear Data Tables 90 (2005) 75-176
Q Moment
Deformation parameter
74Zn secondary beam Production with LISE @GANIL :
76Ge @ 60MeV/u
Be 580umproduction-target
Cocktail beam
Be 450um DegraderSlits Slits
B1B2
Selection Selection
…To D6
IDENTIFICATION
D4
D4->D6
Ionisation Chamber
Plastic
dE E
B3 B3
PRODUCTION
From D4…
D3->D4
Plunger
74Zn @ 34MeV/u1.5e5pps
Beam selection
EXOGAM
TOF D4-D6
MCP MCP
EXOGAM
Plunger
8 EXOGAM Clovers : 4 at 45° and 4 at 135°
)cos(1
1 2
CMlab
EE
74Zn
CD2 34mg/cm2 Be 54mg/cm2
Identification
’
’ =0.2
74Zn*74Zn*
EXOGAM
D
EXOGAM and PLUNGER :
Cologne PLUNGER
B.MOUGINOT, IPNOEURORIB 2010
After Degrader Before Degrader
72Zn Contamination
74Zn component
Energy [keV]
Spectrum Doppler corrected forward angle
)exp(0 t
AR
Rate before degrader
Rate after degrader
Emission rate before and after degrader
Experimental Spectrum :
B.MOUGINOT, IPNO
74Zn
CD2 Be
’
’ =0.2
74Zn*74Zn*
D
Determination of Intensity :
>Peak deconvolution : fit with 4 gaussians : - 2 components for 74Zn (before and after degrader) - 2 components for 72Zn (...)
Doppler corrected Spectrum for 2 (EXOGAM forward angle)after degrader component
before degrader component
after degrader component
before degrader component
74Zn
72Zn
B.MOUGINOT, IPNOEURORIB 2010
Preliminary
First Result :
= 24(2)psB(E2,0+->2+) = 0.209(17)e2b2
c
dd --exp R
d
B.MOUGINOT, IPNOEURORIB 2010
From J.Van De Walle Ph.D
Quadrupole Moment :
B.MOUGINOT, IPNOEURORIB 2010
0.209(17)e2b2
Coulex Measurement
>> Qs = -0.09(25)b2
0.20
0.16
0.12
0.24
0.28
0.0 0.1-0.1-0.2-0.3-0.4-0.5 0.2 0.3 0.4 0.5
Our preliminary result
][bQ s
=0,04(11)
Prolate Oblate
Results :
Our measurement is consistent with the coulex estimation in 74Zn²
B.MOUGINOT, IPNOEURORIB 2010
Comparison with model
Deformation parameterB(E2) strength
-HFB calculation reproduces well N~44 the experimental datawhere it is supposed to be collective (mid-shell)
-Still too much collectivity around N=40 & N=50
B.MOUGINOT, IPNOEURORIB 2010
J.-P Delaroche Physical Review C
N=40N=40
Conclusion :
-Feasibility of plunger technique using in-flight secondary beams and secondary reactionswith LISE spectrometer
->Preliminary Life-time measurement of 2+ state in 74Zn : 24(2)ps-> Constraint on the beta deformation parameter : Beta = 0.04(11)
B.MOUGINOT, IPNOEURORIB 2010
-Result for 72Zn is under analysis.-More accurate value of the Q moment will be extracted for 74Zn and compared to model predictions (HFB and shell model calculations).
THANK YOU
B.MOUGINOT, IPNOEURORIB 2010
