the many faces of laser spectroscopy at isolde: probing the nuclear structure

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

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)


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



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




The simplified Halo picture of 11Be

11Be

10Be

n



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



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



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



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



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


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)


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


- detection method and NMR


- 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.


Collisional-ionization method

U (kV)

norm

aliz

ed io

n co

unt r

ate

17Ne


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)


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!!!

the many faces of laser spectroscopy at isolde: probing the nuclear structure

Documents

acceptedisolde workshop

mgpreliminaryisolde

nmrisolde workshop

cuisolde workshop

b detection method

b detection method

rfq cooling

collinearanticollinear