the many faces of laser spectroscopy at isolde: probing the nuclear structure
DESCRIPTION
The Many Faces of Laser Spectroscopy at ISOLDE: Probing the Nuclear Structure of Exotic Be, Mg, Cu and Ga Isotopes. ISOLDE Workshop, Nov 2008. collinear-anticollinear method with a frequency comb. Halo nuclei. Be. Li. He. rms matter radius (fm). 11 Be. A. - PowerPoint PPT PresentationTRANSCRIPT
The Many Faces of Laser Spectroscopy at ISOLDE:Probing the Nuclear Structure
of Exotic Be, Mg, Cu and Ga Isotopes
ISOLDE Workshop, Nov 2008
ISOLDE Workshop, Nov 2008
collinear-anticollinear method with a frequency comb
rms
matt
er ra
dius
(fm
)
A
He
LiBe
11Be
Halo nuclei
Matter radii from interaction cross sectionsI. Tanihata et al., Phys. Lett. B 206, 592 (1988)
ISOLDE Workshop, Nov 2008
collinear-anticollinear method with a frequency combnu
mbe
r of c
ount
s a.
b.
A (GHz) 2s1/2 → 2p1/2
9Be
11Be
10Be
collinear anti-collinear
First use of a frequency comb at ISOLDE
Collinear anti-collinear spectroscopywith a frequency comb for absolute
frequency determinationof 7,9,10,11Be+
Presentation by Christopher Geppert
Isotope Yield Meas. time11Be 5.7 107 ions/pulse 2 hours
W. Nörtershäuser et al., Phys. Rev. Lett., accepted
ISOLDE Workshop, Nov 2008
collinear-anticollinear method with a frequency comb
A
rms
char
ge ra
dius
(fm
)
experiment
Fermionic Molecular Dynamics
Greens-Function Monte-Carlo Calculations
No-Core Shell Model
from interaction cross section exp.
Experiment versus Theory
W. Nörtershäuser et al., Phys. Rev. Lett., accepted
ISOLDE Workshop, Nov 2008
collinear-anticollinear method with a frequency comb
The simplified Halo picture of 11Be
11Be
10Be
n
W. Nörtershäuser et al., Phys. Rev. Lett., accepted
ISOLDE Workshop, Nov 2008
RFQ cooling and bunching method
First use of a RFQ for laser spectroscopy at ISOLDE
500 MHz per division
coun
ts
79Ga, I=3/2
Isotope Yield Meas. time79Ga ≈ 108 ions/pulse 40 min
presentation by Ernesto Mané
AA(
S 1/2)
/ A(
P 3/2)
4p 2P3/2 → 5s 2S1/2
Tests of spin hypothesesand spin determination
ISOLDE Workshop, Nov 2008
RFQ cooling and bunching method
Spectroscopy of exotic copper isotopes
GHz
100
coun
ts p
er d
ivis
ion 75Cu, I=5/2
(left)
4s 2S1/2 → 4p 2P3/2
GHz
50 c
ount
s pe
r div
isio
n 75Cu(right)
Yield Meas. time
2 105 ions/pulse 7 hours
P. Vingerhoets, PhD in progressK. Flanagan, P. Vingerhoets, publications in preparation
ISOLDE Workshop, Nov 2008
RFQ cooling and bunching method
High-resolution g-factors of the odd-A cases
P. Vingerhoets, PhD in progressK. Flanagan, P. Vingerhoets, publications in preparation
Theory:• reproduces the trend between 59 - 69Cu;• does not describe the drop towards 75Cu;• does not match with the value of 57Cu;
single-particle g( 1f5/2)
single-particle g( 2p3/2)g
fact
or
A
N=40
single-particle-likeground stateof 75Cu (I=5/2)
COLLAPS
I=3/2
ISOLDE Workshop, Nov 2008
RFQ cooling and bunching method
Monopole migration of the 1f5/2 orbital; Inversion at 75Cu
75Cu, I=5/2
S. Franchoo et al., Phys. Rev. C 64, 054308 (2001).I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008).
2p3/2
1f5/2
2p1/2
ISOLDE Workshop, Nov 2008
RFQ cooling and bunching method
Quadrupole moments of the odd-A casesComparison to B(E2) values
Q a
nd B
(E2)
rela
tive
to 63
Cu
N=40Q, COLLAPS
B(E2): 1/2 → 3/2
B(E2): 5/2 → 3/2
A
B(E2) from: I. Stefanescu et al., Phys. Rev. Lett. 100, 112502 (2008).• minimum at N=40 for all;• no evidence for big changes in the collectivity of the ground state from the Q moments;
The - NMR technique
ISOLDE Workshop, Nov 2008
F=0
32P3/2
D2
-2 -1 0 1 2
32S1/2F=1
F=2
F=1
mF
-1 0 1 mF
I=1/2
mI = +1/2
mI = -1/2
h = gBN
electrostaticdeflection
post-accelerationlenses
laser beamoptical-pumping region
magnetscintillation detectors
RF coil
crystal-stopper
X+
B =
B T
optical detection
detection method and NMR
• the mirror partner 21F (T=3/2) has a known magnetic moment; • extracted the isoscalar and isovector parts of the magnetic moment; J. Krämer, PhD and paper in progress.
Spin and magnetic moment 21Mg
|A(g)| (I+1/2)
NMR
HFS 21Mg II, D2
(MHz)
preliminary
NMR 21Mg, MgO
Larmor (MHz)
ISOLDE Workshop, Nov 2008
Ground-state properties of 21Mg
= -0.983(7)N I = 5/2
Yield Meas. time
1.6 104 ions/pulse 8 hours
- detection method and NMR
• (21Mg) + (21F) > d5/2 + d5/2, contrary to the systematics, σ = 1.15(2);• higher value than the shell-model prediction → isospin nonconservation;• to understand of the isovector moment in light of the decay properties;J. Krämer, PhD and paper in progress.
A
σ =(Tz) + (-Tz) - I
p + n - 1/2
σ j=l+1/2 = 1
σ j=l-1/2 = -j/(j+1)
Spin expectation value for A=21preliminary
ISOLDE Workshop, Nov 2008
- detection method and NMR
ISOLDE Workshop, Nov 2008
- detection method and NMR (NQR)
Quadrupole moment of the two-neutron halo 11Li
1 kHz per division
1% a
sym
met
ry p
er d
ivis
ion
NQR of 11Li in Zn
17 kHz
A
|Q|
(mb)
AMD
cluster
p-sd shell model
NCSM
Yield Meas. time
500 ions/pulse 8 hours
9Li - 11Li: |Q / Q| = 8.8(15)%R. Neugart et al., Phys. Rev. Lett. 101, 132502 (2008).
9Li - 11Li: r21/2 / r21/2 = 11(2)%R. Sánchez et al., Phys. Rev. Lett. 96, 033002 (2006).
Cluster correlations in Ne isotopes
N
rms
char
ge ra
dius
(fm
) Ne COLLAPS [1]
FMD [1]
Fricke & Heilig [2]
[1] W. Geithner et al., Phys. Rev. Lett. (2008), submitted.[2] G. Fricke and K. Heilig, Nuclear Charge Radii, vol. I / 20 (Springer, 2004), ISBN 3-540-42829-1.
ISOLDE Workshop, Nov 2008
Collisional-ionization method
U (kV)
norm
aliz
ed io
n co
unt r
ate
17Ne
ISOLDE Workshop, Nov 2008
The collisional-ionization technique
Collisional-ionization method
Isotope Yield Meas. time17Ne 3.5 103 ions/pulse 1 hour28Ne 50 ions/pulse
electrostaticdeflection
optical detection
X+
tape stations with detection
post-accelerationlenses
charge-exchangecell
gas target (Cl2)
ISOLDE Workshop, Nov 2008
C. Geppert**, J. Krämer, A. Krieger,R. Neugart, W. Nörtershäuser**, D. Tiedemann, M. Žáková
Institut für Kernchemie, Johannes Gutenberg-Universität Mainz, D-55099 Mainz, GermanyK. Blaum and D. T. Yordanov
Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, GermanyM. Avgouleva, M. L. Bissell, M. De Rydt, K. Flanagan*, G. Neyens, and P. Vingerhoets
Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven, BelgiumJ. Billowes, B. Cheal, and E. Mane
University of Manchester, Manchester, M13 9PL United KingdomD. H. Forest
School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UKR. Sánchez
GSI, D-64291 Darmstadt, GermanyM. Kowalska
CERN, Physics Department, CH-1211 Geneva 23, SwitzerlandP. Lievens
Laboratorium voor Vaste-Stoffysica en Magnetisme, Katholieke Universiteit Leuven,B-3001 Leuven, Belgium
H. H. StrokeNew York University, New York, NY-10003, USA
* current affiliation: IPN Orsay, 15 Rue Georges Clemenceau, Orsay, France, 91406** second affiliation: GSI, D-64291 Darmstadt, Germany
With respect to the authors of the work on Li and Ne!!!
ISOLDE Workshop, Nov 2008