ISOLDE Workshop 2009 1/XX Nuclear Charge Radii of Mg Isotopes by Laser Spectroscopy with Combined...
11
ISOLDE Workshop 2009 1/XX Nuclear Charge Radii of Mg Isotopes by Laser Spectroscopy with Combined Fluorescence and β-decay Detection J. Krämer 1 , D.T. Yordanov 2 , M.L. Bissell 3 , K. Blaum 2 , M. De Rydt 3 , Ch. Geppert 1,4 , M. Hammen 1 , K. Kreim 2 , A. Krieger 1 , M. Kowalska 5 , R. Neugart 1 , G. Neyens 3 , W. Nörtershäuser 1,4 , R. Sanchez 4 , B. Sieber 1 , P. Vingerhoets 3 1 Institut für Kernchemie, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany 2 Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany 3 Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium 4 GSI, D-64291 Darmstadt, Germany 5 CERN, Physics Department, CH-1211 Geneva 23, Switzerland
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Transcript of ISOLDE Workshop 2009 1/XX Nuclear Charge Radii of Mg Isotopes by Laser Spectroscopy with Combined...
ISOLDE Workshop 2009 1/XX
Nuclear Charge Radii of Mg Isotopes by Laser Spectroscopy
with Combined Fluorescence and β-decay Detection
J. Krämer1, D.T. Yordanov2, M.L. Bissell3, K. Blaum2, M. De Rydt3, Ch. Geppert1,4, M. Hammen1, K. Kreim2, A. Krieger1, M. Kowalska5, R. Neugart1, G. Neyens3, W.
Nörtershäuser1,4, R. Sanchez4, B. Sieber1, P. Vingerhoets3
1Institut für Kernchemie, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany2Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
3Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium4GSI, D-64291 Darmstadt, Germany
5CERN, Physics Department, CH-1211 Geneva 23, Switzerland
ISOLDE Workshop 2009 2/XX
Nuclear Charge Radii of Mg Isotopes by Laser Spectroscopy
with Combined Fluorescence and β-decay Detection
J. Krämer1, D.T. Yordanov2, M.L. Bissell3, K. Blaum2, M. De Rydt3, Ch. Geppert1,4, M. Hammen1, K. Kreim2, A. Krieger1, M. Kowalska5, R. Neugart1, G. Neyens3, W.
Nörtershäuser1,4, R. Sanchez4, B. Sieber1, P. Vingerhoets3
1Institut für Kernchemie, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, Germany2Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
3Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, Belgium4GSI, D-64291 Darmstadt, Germany
5CERN, Physics Department, CH-1211 Geneva 23, Switzerland
ISOLDE Workshop 2009 3/XX
The detection method
LASER
+
++ + + + + + + +
BII
B T
tuning voltage
weak guiding field
strong field
scintillator and PMT
MgO crystal
optical pumping -asymmetrydetectionDoppler tuningdeflection
_
+
acceleration
+
optical detection
Mg+ fromISOLDE
PMT
LASER
+
++ + + + + + + +
BIIBII
B TB T
tuning voltage
weak guiding field
strong field
scintillator and PMT
MgO crystal
optical pumping -asymmetrydetectionDoppler tuningdeflection
_
+
acceleration
+
optical detection
Mg+ fromISOLDE
PMT
2S1/2
2P1/2
F=1
F=0
F=0
F=1
-1 0 1
-1 0 1
σ+ σ+
mF
mF
2S1/2
2P1/2
F=1
F=0
F=0
F=1
-1 0 1
-1 0 1
σ+ σ+
mF
mF
polarization
λ=280.36nm
ISOLDE Workshop 2009 4/XX
Shell Structure of Mg Isotopes - „Island of Inversion“
pf
sd
8
20
1d5/2
2s1/2
1d3/2
1f7/2
2p3/2
30Mg (Z=12, N=18)
pf
sd
8
20
1d5/2
2s1/2
1d3/2
1f7/2
2p3/2
32Mg (Z=12, N=20)
pf
sd
8
20
1d5/2
2s1/2
1d3/2
1f7/2
2p3/2
31Mg (Z=12, N=19)
2p-2h
= -0.88355(15)N
Theory= -0.84N
Schmidt= -1.9N
pf
sd
8
20
1d5/2
2s1/2
1d3/2
1f7/2
2p3/2
33Mg (Z=12, N=21)
2p-2h
= −0.7456(5) N
Theory= -0.71N
Schmidt= -1.9N
ISOLDE Workshop 2009 5/XX
FNe
NaMg
AlSi
1718
1920
2122
23
910
1112
1314
N
Z
31Mg
29Na28Ne
34Al32Mg
33Mg
34Mg
30Na
31Na30Ne
The “island of inversion” in terms of the SPHERICAL shell model.The height of the boxes represents the amount of particle-hole configurations present in
the ground-state wave functions.(analogous to a figure from P. Himpe et. al., Phys. Lett. B 658, 203 (2008).)
The Island of Inversion an Island of Deformation?
ISOLDE Workshop 2009 6/XX
Does Deformation Explain the 31,33Mg spins and moments?
• QS(31Mg)=0. Quadrupole-moment measurements of 29,33Mg - not feasible;• Necessity of a common observable for all isotopes in order to detect the transition to a deformed configuration;
E sp (M
eV)
33Mg, I = 3/2(-)
1/2[330]: = -0.76N
3/2[202]: = +0.80N
3/2[321]: = -0.32N
31Mg, I = 1/2+
1/2[200]: = -0.86N
31Mg = -0.88355(15)N
33Mg = -0.7456(5)N
ISOLDE Workshop 2009 7/XX
F=0
32P3/2
D2
32S1/2F=1
F=2
F=1 -1 0 1 mF
-1 0 1 mF
-10
1
-1 0 1
gF = 1.7
gF = 1.0
F=0
32P3/2
D2
-2 -1 0 1 2
32S1/2F=1
F=2
F=1
mF
-1 0 1 mF
-2 -1 0 1 2
-1 0 1
gF = 1.0
gF = 1.0
Influence of the guiding field on the atomic lines:• shift• broadeningOne can solve numerically the rate equations and quantitatively describe these effects.M. Keim et al., Eur. Phys. J. A 8, 31 (2000).
B = 0 B > 0
Isotope shifts by detection
iAA = Ki (m-m)/(mm)+Fi r2AA
ISOLDE Workshop 2009 8/XX
HFS 31Mg II, D2 Simulated spectra of 31Mg II, D2
M. Kowalska et al., Phys. Rev. C 77, 034307 (2008).
Isotope shifts by detection
ISOLDE Workshop 2009 9/XX
First use of detection for isotope-shift measurments
0,3 0,4 0,5 0,6 0,7 0,814000
15000
16000
17000
18000
19000
coun
ts
scan voltage / V
-1,0 -0,5 0,0 0,5 1,0 1,5 2,0 2,5 3,0
13000
14000
15000
16000
17000
18000
coun
ts
scan voltage / V
-1,0 -0,5 0,0 0,5 1,0 1,5 2,0 2,5 3,0-0,025
-0,020
-0,015
-0,010
-0,005
0,000
0,005
asym
met
ry
scan voltage / V
-2 -1 0 1 2 3
-0,06
-0,04
-0,02
0,00
0,02
0,04
asy
mm
etr
y
scan voltage / V
0,7 0,8 0,9 1,0 1,1 1,280000
90000
100000
110000
120000
cou
nts
scan voltage / V
29Mg optical
29Mg asym.
30Mg triggered onthe release
31Mg asym.
32Mg photon-ioncoincidence
Preliminary Results on 24Mg - 32Mg from September 2009
Proof of principle:29Mg optical and detection are consistent!
29Mg 1.2 106 ions/C30Mg 4.6 105 ions/C31Mg 1.5 105 ions/C32Mg 4.2 104 ions/C33Mg 5.3 103 ions/C
21Mg 3 103 ions/C21Na 4 108 ions/C
ISOLDE Workshop 2009 10/XX
Charge radii of Magnesium Isotopes
King plotKSMS
=367,3(3) GHz u
radii from muonic data
theoretical calculation
Fricke et al., Phys. Rev. C45 (1992) 80
Berengut et al., Phys. Rev. A68 (2003) 022502
electronic factor F
2r
Isotope shifts
reference radius: rC (26Mg) =3.034(2) fm
Fricke et al., Phys. Rev. C45 (1992) 80
Bx
AA
AArF
AKK
y
AA
AA AA
SMSNMSAAIS '
'
'
' '2'
PRELIMIN
ARY
24 25 26 27 28 29 30 31 32
3.02
3.04
3.06
3.08
3.10
3.12
3.14
3.16
3.18
3.20
12 13 14 15 16 17 18 19 20
neutron number
rms
rad
ius
/ fm
atomic mass number
ISOLDE Workshop 2009 11/XX
Discussion: PRELIMINARY
PRELIMIN
ARY
12 13 14 15 16 17 18 19 20
2.96
2.98
3.00
3.02
3.04
3.06
3.08
3.10
3.12
3.14
3.16
3.18
3.20
Mg Na
rms
radi
us /
fm
neutron number
values for Na taken fromHuber et al., Phys. Rev. C18 (1978) 2342Otten, Treat. Heav. Ion Sci. 8 (1989) 515
radii• Mg and Na reveal similar trend• Indication for an effect at 30Na and 31Mg
oddNr
rNN
NN
N1,12
1,22
Isotope
31Mg 0.958
29Mg 0.489
27Mg 0.164
staggering parameter <1, well within the known systematics
Isotope shift 24Mg-26Mg: 3077(2)(9) MHz -in agreement with trap measurement: 3084.905(93) MHz
Batteiger et al. Phys. Rev. A80 (2009) 022503
