Diapositive 1

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The DESIR low energy beam facility at SPIRAL2
Decay, Excitation and Storage of Radioactive
Ions http//www.cenbg.in2p3.fr/desir
Collaboration promoting ISOL beams at SPIRAL2
Spokes-person B. Blank, Bordeaux
blank_at_cenbg.in2p3.fr GANIL liaison J.-C.
Thomas, Caen thomasjc_at_ganil.fr

• DESIR _at_ SPIRAL2
• Beam preparation
• The DESIR Facility
• Selected physics cases
• Cost estimates / Synergies / Milestones

B. Blank, CENBG LEA
workshop, Catania, 13-15 october 2008
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Why a low energy beam facility at SPIRAL2 ?

• Different production modes considered
• n-induced fission -gt neutron-rich nuclei
• fusion reaction -gt (super)heavy, n-deficient
  nuclei ( refractory elements)
• fragment products at low-energy -gt light exotic
  nuclei

• Large variety and high degree of purity for
  exotic beams
• all kind of ionization sources (including laser
  ionization)
• high-efficiency RFQ cooler/buncher
  high-resolution mass separator

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DESIR physics 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 (or T) violation with e.g. Radium
• Solid state physics and other applications

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N F S
SPIRAL2 layout
SRI
LINAG
Fusion reaction 14 A.MeV A/Q3 HI, 1 mA
S3
DESIR
Level -1
Level -1
n-induced 238U fission 40 MeV 5 mA deuterons 1014
fissions/s
Fragmentation ISOL 95 A.MeV 36Ar 3 kW
Production building
GANIL/ SPIRAL
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RFQ and HRS cave in the production building
Production building
SHIRaC
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SHIRaC SPIRAL2 High Intensity Radiofrequency
Cooler
Prototype RFQ linear Paul trap, work initiated at
CSNSM Orsay (D. Lunney) Under development at LPC
Caen (G. Ban, F. Duval)
Goals High-voltage (20 kV), high frequency (20
MHz) linear radio-frequency quadrupole trap for
strong confinement of mA beams should deliver
beams with 1 p.mm.mrad emittance Results so
far Prototype tested at high-current separator
SIDONIE (Orsay)
O. Gianfrancesco et
al., Proc. EMIS2007
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High resolusion mass separator

• symmetric design, inspired by the CARIBU HRS at
  ANL
• with two magnetic dipoles (D)
• six quadrupoles (Q)
• two sextupoles (H)
• one multipole (M)
• combined as QQHQD M DQHQQ
• minimized aberrations,
• large mass dispersion
• expected performances M/DM 2.104 for a 1
  p.mm.mrad at 10 to 60 keV

Beam profile in x-direction
Suggested layout
T. Kurtukian-Nieto, CENBG
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Laser room (mezzanine)
DESIR layout level 0
Identification station with tape
Beam from S3
Level 0
Level -1
Beam from Production building
Level -1
Crane access to basement
5 m
Beam from SPIRAL1
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DESIR layout - Level -1
Beam from S3
Work shop
Radio lab
storage
Beam from Production building
X
Supply
Limits DESIR hall
Beam from SPIRAL1
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Refractory elements For ISOL-type studies
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LUMIERE Laser Utilisation for Measurement and
Ionization of Exotic Radioactive Elements
F. Le Blanc ,Orsay G. Neyens, Leuven P. Campbell,
Manchester

• Collinear Laser spectroscopy
• - spins
• - magnetic moments
• - quadrupole moments
• - change of charge radii
• b-NMR spectroscopy
• - nuclear gyromagnetic factor
• - quadrupole moment
• N50, N64, N82,
• Microwave double resonance in a Paul trap
• - hyperfine anomaly and higher order momenta
  (octupole and hexadecapole deformation)
• Eu, Cs, Au, Rn, Fr, Ra, Am .

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BESTIOL BEta decay STudies at the SPIRAL2 IsOL
facility

• Decay studies with halo nuclei
• Clustering studies in light nuclei
• b-delayed charged-particle emission e.g.
  proton-proton correlation
• Super-allowed b decays and the standard model of
  electro-weak interaction
• Deformation and Gamow-Teller distribution
• 2n correlations, Pn and nuclear structure
  (r-process)
• ...

M.J.G. Borge, Madrid B. Blank, Bordeaux
b-g setup, B. Blank (Bordeaux)
TETRA, Y. Penionzhkevich (Dubna)
TAS, B. Rubio (Valencia)
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MLLTRAP

• High-accuracy mass measurements
• - unitarity of CKM matrix (Vud) 50Mn, 54Co
  with DM/M10-10
• - transuranium isotopes (beams from S3)
  M(Zgt102)
• In-trap spectroscopy
• - conversion electron and a spectroscopy
  shape coexistence
• Trap-assisted spectroscopy
• - b decay studies of isomerically pure
  radioactive species

P. Thirolf , Munich
Set-up being installed at MLL/Garching
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KVI atomic trapping facility MOT

• New limits on scalar and tensor contributions in
  the weak interaction
• New limits on time-reversal violation in beta
  decay
•  Systematic of atomic parity non-conservation in
  a long isotopic chain

H. Wilschut, Groningen
? detector
MCP
V0
-V0
0
Experimental set-up at KVI
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Search for exotic interactions
e
nucleus
q
ne

• b-n angular correlation

requires to measure the recoil ion b particle

• within the SM

x Fermi fraction r GT/F mixing ratio

• beyond the SM

a contains quadratic S and T contributions
O. Naviliat-Cuncic et al., LPC Caen
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CVC, CKM, exotic currents 0 ? 0 b decays
3071.4 (8) s
Measurements - Q value
- T1/2 -
branching ratios
? Vud00 0.97418(26) VusK
0.2254(21) VubB 0.00367(47)
?
1.0000(11)
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b-NMR spectroscopy
b-asymmetry in the decay of polarized nuclei in a
magnetic field

• Zeeman splitting related to gI and QS

MI
I
M-I
with
and

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

• DgI/gI 10-3, DQS/QS 10-2

• complementary technique to collinear laser
  spectroscopy

• suitable for light elements (low QS values)

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

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

n
J
with
F
DEHFS

• Hyperfine structure constants

and

• Collinear laser spectroscopy DmI/mI 10-2,
  DQS/QS 10-1 for heavy elements

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

• related to the mass and size differences

J2, F2
dnA,A
J2, F2
J1, F1
J1, F1

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

• study of nuclei shape (deformation)

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The physics case for b-NMR on polarized beams
nuclear structure towards and beyond 78Ni
Kr
Produced at SPIRALII with d-induced fission
Se
Ge

• Evolution of n orbits
• from Z40 to Z28
• ground state spins and moments
• of 83Ge, 81Zn, 79Ni and
• of 81Ge, 79Zn, 77Ni
• g-factors can reveal erosion
• of N50 shell closure

Zn
Ni
Lifetime OK for b-NMR studies
G. Neyens et al., KU Leuven
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DESIR building costs
Infrastructure Estimated costs
Available funds DESIR building 6000
k 2000 k (CPER) RFQ
320 k 320 k (CPER) HRS
1000 to 1500 k
- beam lines 3600 k
- RFQ off-line sources
200 k Total (preliminary) 11000 to
16000 k
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Equipments foreseen at DESIR
Collinear laser spectroscopy Manchester 30
0 k Orsay 200 k Leuven 150
k b-NMR setup Leuven 100 k b-charged
particle setup France, ANR VS3 2006 240
k Spectroscopy setup Madrid 200 k TAS
setup Valencia 180 k Neutron detection -
multiplicity, TETRA setup Dubna 200 k -
energy LPC Caen and others 400 k MLL trap
system LMU München 860 k MOT trap KVI
Groningen 500 k Total (preliminary)
3300 k
LUMIERE
BESTIOL
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Synergies with FAIR/NuSTAR
Beam preparation RFQs, traps, low-energy beam
diagnostics Trap-assisted spectroscopy
(MATS) Laser spectroscopy (LASPEC) Neutron
detection (NCAP) New types of charged-particle
and gamma detectors (e.g. LaBr2) .
To a large extend the same community!!!!
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DESIR Milestones

• Dec 2008 technical report (SPIRAL2 TAC)
• 2009 call for experiment proposals
• 2010 building design study
• 2011 construction of the building
• end 2013 day 1 of operation

B. Blank, M.J.G. Borge, P. Cambell, F. Leblanc,
M. Lewitowicz, D. Lunney, O. Naviliat-Cuncic, G.
Neyens, B. Rubio, P. Thirolf, J.-C. Thomas and
many more Opened to everyone interested --------
--------- http//www.cenbg.in2p3.fr/desir