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DESIR DESIR @ SPIRAL2 organization & scientific program layout of the facility status and perspectives Laser spectroscopy @ DESIR: the LUMIERE LUMIERE project Laser spectroscopy studies Laser spectroscopy studies at at the the DESIR DESIR facility of SPIRAL2 facility of SPIRAL2 J.C. Thomas – XV th Colloque GANIL, Giens 2006 physics cases experimental techniques research program

DESIR DESIR @ SPIRAL2 organization & scientific program layout of the facility status and perspectives LUMIERE Laser spectroscopy @ DESIR: the LUMIERE

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DESIRDESIR @ SPIRAL2

organization & scientific program

layout of the facility

status and perspectives

Laser spectroscopy @ DESIR: the LUMIERELUMIERE project

Laser spectroscopy studiesLaser spectroscopy studies at the at the DESIRDESIR facility of facility of SPIRAL2 SPIRAL2

J.C. Thomas – XVth Colloque GANIL, Giens 2006

physics cases

experimental techniques

research program

DESIRDESIR

Désintégration, Excitation et Stockage d’Ions Radioactifs

Results from the SPIRAL2 workshop held at GANIL on July 2005

« Physics with low energy beams at SPIRAL2 »

http://spiral2ws.ganil.fr/2005/lowenergy/program/presentations/

An open collaboration to promote ISOL beams at SPIRAL2

Follows the earlier proposition of a low-energy RIB facility at SPIRAL

- Promotors (1998): G. Auger, B. Blank, C. Le Brun, ….

- LIRAT facility (2005): 6He, 19Ne, 32,35Ar @ ~ 30 keV

talk by A. Merytalk by A. Mery

DESIRDESIR organizationorganization

Working groups / correspondents:

- Beam handling and beam preparation / [email protected]

- Laser spectroscopy / [email protected]

- Decay spectroscopy / [email protected]

* spokes-person: B. Blank, [email protected]

* GANIL correspondent: J.-C. Thomas, [email protected]

Links to SPIRAL2 project management:

- Scientific program: M. Lewitowitcz

- Installation: M.-H. Moscatello

DESIRDESIR physics programphysics program

Decay spectroscopy

- decay properties and nuclear structure studies

- particle-particle correlations, cluster emission, GT strength

- exotic shapes, halo nuclei

Laser spectroscopy

- static properties of nuclei in their ground and isomeric states

- nuclear structure and deformation

Fundamental interactions

- CVC hypothesis, CKM matrix unitarity via 0+ 0+ transitions

- exotic interactions (scalar and tensor currents)

- CP and T violation

Solid state physics and other applications

A new experimental area of about 1500m2

Availability from day 1

Run in parallel with post-accelerated beamsFast change of the mass settingNeutron-rich and neutron-deficient beams

More than one production station Different target-ion source assemblies including a laser ionization source Different production modes including fusion-evaporation and DI reactions

Use of isotopically separated beams A high resolution mass separator with a resolution of M/M>5000

Extension of the current LIRAT beam line

TheThe DESIRDESIR facility @ SPIRAL2facility @ SPIRAL2technical requirementstechnical requirements

LINAG

Production building

GANIL facility

LIRAT

DESIR

TheThe DESIRDESIR facility @ SPIRAL2facility @ SPIRAL2layoutlayout

LINAG

Production building

DESIRHRS

Ident. Station

Exp. Area

GANIL

GANIL facility today

DESIR building - UndergroundDESIR building - Underground

DESIR building -DESIR building - Ground floorGround floor

Laser Laser SpectroscopySpectroscopy

Decay studiesDecay studies

Other Other purposespurposes

Fundamental Fundamental InteractionsInteractions

Spectroscopy Spectroscopy of trapped of trapped

beamsbeams

talk by A. Herlerttalk by A. Herlert talk by M.J.G. talk by M.J.G. BorgeBorge

talks by A. Mery and N. Severijnstalks by A. Mery and N. Severijns

talk by P. Delahayetalk by P. Delahaye

this talk and P. Mueller

Cooling/BunchingCooling/Bunching

Status of theStatus of the DESIRDESIR ProjectProject

DESIR building (new experimental area)

High resolution separator

Beam preparation (cooler)

preliminary design study: B.Blank et al., CEN Bordeaux-Gradignan

preliminary design study: D. Lunney et al., CSNSM Orsay

O. Naviliat et al., LPC Caen + D. Lunney et al., CSNSM Orsay

LoILoI to be submitted in October 2006 (Contact: B. Blank)

Presentation of the DESIR Project to the IN2P3 SC in July 2006

Synergies with other facilitiesSynergies with other facilities

ALTO: laser ionization source, laser spectroscopy

FAIR/NuSTAR: MATS, LASPEC, NCAP, DESPEC

RIKEN/RIBF: SLOWRI

Common issues

beam preparation using coolers and traps

low-energy beam diagnostics

new types of gamma and neutron detectors

Towards Towards DESIRDESIR: LIRAT extension: LIRAT extension Multi-beam facility (physics program 2012)

Tests and development for SPIRAL2 & DESIR

LIRAT today

SPIRAL2SPIRAL2

11++ nn++

LPC TrapLPC Trap

TestsTests

Spec.Spec.

TheThe LUMIERELUMIERE project @ project @ DESIRDESIRLaser Utilisation for Measurement and

Ionization of Exotic Radiaoctive Elements

Spokes-person: F. Le Blanc, [email protected]

Physics cases:

Nuclear structure and deformation studies far from stability, in the vicinity of closed shells

Hyperfine anomaly and high-order components of the hyperfine interaction

from systematic measurements of the static properties of exotic nuclei in their ground and isomeric states: <r²>, I, Qs, I

from precise measurements of the hyperfine structure constants

collinear laser spectroscopy + -NMR

double laser + RF spectroscopy in traps

Atomic hyperfine structureAtomic hyperfine structure

Interaction between an orbital e- (J) and the atomic nucleus (I,I,QS)

results in a hyperfine splitting (HFS) of the e- energy levels

J

n

FEHFS

1)J(J1)I(I1)F(FK with

I.J(0)Hμ eIA Hyperfine structure constants: and (0)Ve zzSQB

1)I.J1)(2J2(2I

1)1)J(JI(I1)K(K43

..K2

ΔEHFS

BA

Collinear laser spectroscopy: / ~ 10-2, QS/QS ~ 10-1 for heavy elements

Isotope shift measurementsIsotope shift measurements

Frequency shift between atomic transitions in different isotopes of the same chemical element

related to the mass and size differences

A'A,2SMSNMS

A' A, rF.A.A'

A)(A').K(K

J1, F1

J2, F2

J1, F1

J2, F2

A,A’

mean square charge radius variations with a precision ~ 10-3

study of nuclei shape (deformation)

previous experiments:

Isotope shift measurementsIsotope shift measurements

N~82 N~104

onset of deformation at N=82 (slope ↔ rigidity)

dynamical effects (vibration)

shape coexistence

shape transition (even-odd staggering)

COMPLISCOMPLIS

with I ~ 103-104 pps:

Isotope shift measurements at Isotope shift measurements at DESIRDESIR

N~50: neutron skin in N > 50 Ge isotopes (neutron star studies) deformation in N ≤ 50 Ni isotopes (collectivity vs magicity)

N~82: shape evolution for Z ≤ 50 (Ag, Cd, In, Sn)

N~64: strongly oblate shapes predicted in Rb, Sr and Y for N > 64

Z~40: shape transitions predicted in the Zr region (Mo, Tc, Ru)

Rare earth elements: large deformation and shape transitions predicted (Ba, Nd, Sm)

)21

1)(m)(.(3cos1)4I(2I

Q3h.Lh.ΔE 2

1-mm,

θ

-NMR spectroscopy-NMR spectroscopy

h

.B.L

0N Ig

-asymmetry in the decay of polarized nuclei in a magnetic field

Zeeman splitting related to gI and QS

I

M+I

M-I

resonant destruction of the polarization (i.e. -asymmetry) by means of an additional RF magnetic field

h

.V. ZZQ

SQewith and

B0

gI/gI ~ 10-3, QS/QS ~ 10-2

complementary technique to collinear laser spectroscopy

suitable for light elements (low QS values)

previous experiments at COLLAPSCOLLAPS:

Collinear laser andCollinear laser and-NMR spectroscopy-NMR spectroscopy

from the position of hyperfine transitions: spin assignment and sign of gI for the g.s. of 31MgHFS 31Mg1+

from -NMR: precise measurement of |gI|

RF (MHz)

as

ym

me

try

strongly deformed intruder I = 1/2+ g.s. of 31Mg, G. Neyens et al, PRL 94, 022501 (2005)

from QS measurements via -NMR: QS(11Li) > QS(9Li) p-n interaction + halo n orbitals, D. Borremans, Ph.D. Thesis, 2004, KU Leuven, R. Neugart et al.

-NMR spectroscopy at -NMR spectroscopy at DESIRDESIR

with I ≥ 5.103 pps, T½ from 1 ms to 10 s, beam purity > 50 %:

in combination with collinear laser spectroscopy whenever the spin and the configuration of the state is not known

in case QS is to small to be measured by collinear laser spectroscopy

N~50: g factor of neutron-rich Ga and Cu isotopes to determine where

the inversion of the p3/2 and f5/2 orbitals occurs

persistence of the N=50 shell gap from the g.s. configuration of N=49 (g9/2) and N=51 (d5/2) even Z nuclei (81,83Ge, 79,81Zn, 77Ni)

N~82:

g.s. configuration from gI measurements

Double laser and RF spectroscopy in trapsDouble laser and RF spectroscopy in traps

In a Paul trap (low magnetic field)

In a Penning trap (high magnetic field)

precise determination of the hyperfine constants A, B as well as C (magnetic octupole moment) and D (electric exadecapole

moment) = high-order deformation parameters

RF scan of hyperfine transitions between Zeeman levels

precise determination of the hyperfine constant A

hyperfine anomaly (nuclear magnetization extension) constraining the computation of the nuclear wave function

high precision on gI (gI/gI ~ 10-4)

looking at different isotopes: neutron radius variations + PNC

No Doppler effect accurate measurements

Double laser and RF spectroscopy in trapsDouble laser and RF spectroscopy in traps

at DESIRDESIR (I>100 pps, T½>100 ms)

Previous results: O. Becker et al., Phys. Rev. A48, 3546 (1993)

high-order deformation in the actinide region: Rn, Fr, Ra, Am

Hyperfine Constant

151Eu+ [Hz] 153 Eu+ [Hz]

A 1 540 297 394 (13) 684 565 993 (9)

B - 660 862 (231) -1 752 868 (84)

C 26 (23) 14 (7)

D -6 (5) -5 (2)

hyperfine anomaly: Au, Eu, Cs

TheThe LUMIERELUMIERE collaborationcollaboration

F. Le BlancF. Le Blanc, G. Neyens (-NMR), P. Campbell, K. Flanagan , S. Franchoo, C. Geppert, M. Kowalska, I. Moore, R. Sifi, C. Theisen, J.-C. Thomas,…

and others are welcome !!!