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The The DESIRDESIR low energy beam facility at SPIRAL2 low energy beam facility at SPIRAL2DDecay, EExcitation and SStorage of RRadioactive IIons
http://www.cenbg.in2p3.fr/desir
B. Blank, CENBG LEA workshop, Catania, 13-15 october 2008
Collaboration promoting ISOL beams at SPIRAL2
Spokes-person: B. BlankB. Blank, Bordeaux; [email protected] GANIL liaison: J.-C. Thomas,J.-C. Thomas, Caen; [email protected]
DESIR @ SPIRAL2 Beam preparation The DESIR Facility Selected physics cases Cost estimates / Synergies / Milestones
Different production modes considered n-induced fission -> neutron-rich nuclei fusion reaction -> (super)heavy, n-deficient nuclei (+ refractory
elements) fragment products at low-energy -> 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
Why a low energy beam facility atWhy a low energy beam facility at SPIRAL2SPIRAL2 ??
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 (or T) violation with e.g. Radium
Solid state physics and other applications
SPIRAL2 layoutSPIRAL2 layout
GANIL/SPIRAL
S3
DESIRDESIR
Level -1
Level -1
LINAG
NFS
15 m
Production building
Fragmentation + ISOL95 A.MeV 36Ar 3 kW
n-induced 238U fission40 MeV 5 mA deuterons
1014 fissions/s
Fusion reaction14 A.MeV A/Q=3 HI, 1 mA
SRI
8m
12m
HRS
RFQ
storage and maintenance
Legend:
Electronics
Quadrupole
Sextupole
Multipole
Dipole
RFQ and HRS cave in the production building
Production building
SHIR
aCSH
IRaC
SHIRaCSHIRaC SSPIRAL2 PIRAL2 HHigh igh IIntensity ntensity RaRadiofrequency diofrequency CCoolerooler
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 A beams; should deliver beams with 1 .mm.mrad emittance
Results so far: Prototype tested at high-current separator SIDONIE (Orsay)
O. Gianfrancesco et al., Proc. EMIS2007
High resolusion mass separatorHigh 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/M ~ 2.104 for a 1 .mm.mrad at 10 to 60 keV
Beam profile in x-direction
Suggested layout
T. Kurtukian-Nieto, CENBG
DESIR layout – level 0Laserroom
(mezzanine)
DA
Qroom
Controlroom
MLL trap
Collinea
r Las
er
spec
trosc
opy
-NMR
RFQbun-cher
off-linesource1
off-linesource2
+
Decay
setup
LPCtrap
Beam from SPIRAL1
Beam from S3
Bea
m fr
om
Prod
uctio
n bu
ildin
g
Generalpurpose
ElectronicsDeskAccess5 m
Level -1
Level 0
TAS
Neutronditch
Leve
l -1
Crane access to basement
Double MOT
Genera
l
purpose
IS
Identification station with
tape
LN2Gas &
w
aste storage
LUMIERE BESTIOL
Supply
Electri-city
Gray Room 2
Gray Room 1
AssemblyRoom 3
ControlRacks
Interfaces
HV
supplies
Crane access to basement
Stor- age 1
Assembly Room 2
Assembly Room 1
Stor- age 2
Radiolab
5 m
storage
Neutronditch
DESIR layout - Level -1
Limits DESIR hall
freeBeam from SPIRAL1
Bea
m fr
om
Prod
uctio
n bu
ildin
g
Workshop
Beam from S3
X
Refractory elementsFor ISOL-type studies
• Collinear Laser spectroscopy: - spins - magnetic moments - quadrupole moments - change of charge radii
• -NMR spectroscopy: - nuclear gyromagnetic factor - quadrupole moment N=50, N=64, N=82, …
• Microwave double resonance in a Paul trap: - hyperfine anomaly and higher order momenta (octupole and hexadecapole deformation) Eu, Cs, Au, Rn, Fr, Ra, Am ….
LUMIERELUMIERELLaser aser Utilisation for tilisation for MMeasurement and easurement and
IIonization of onization of EExotic xotic RRadioactive adioactive EElementslements
F. Le Blanc ,OrsayF. Le Blanc ,OrsayG. Neyens, LeuvenG. Neyens, LeuvenP. Campbell, ManchesterP. Campbell, Manchester
• Decay studies with halo nuclei• Clustering studies in light nuclei• -delayed charged-particle emission: e.g. proton-proton correlation
• Super-allowed decays and the standard model of electro-weak interaction• Deformation and Gamow-Teller distribution• 2n correlations, Pn and nuclear structure (r-process) • ...
BESTIOLBESTIOLBEBEta decay STSTudies at the SPIRAL2 IIsOLOL facility
TETRA, Y. Penionzhkevich (Dubna)TAS, B. Rubio (Valencia) setup, B. Blank (Bordeaux)
M.J.G. Borge, MadridM.J.G. Borge, MadridB. Blank, BordeauxB. Blank, Bordeaux
MLLTRAPMLLTRAP
•High-accuracy mass measurements - unitarity of CKM matrix (Vud): 50Mn, 54Co with M/M~10-10
- transuranium isotopes (beams from S3): M(Z>102) • In-trap spectroscopy: - conversion electron and spectroscopy: shape coexistence • Trap-assisted spectroscopy - decay studies of isomerically pure radioactive species
P. Thirolf , MunichP. Thirolf , Munich
Set-up being installed at
MLL/Garching
KVI atomic trapping facility: MOTKVI 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, GroningenH. Wilschut, Groningen
Experimental set-up at KVI
detector
MCP
-V0 +V00
• within the SM
x : Fermi fraction; : GT/F mixing ratio
• beyond the SM
contains quadratic S and T contributions
• angular correlation
requires to measure the recoil ion + particle
Search for exotic interactionsSearch for exotic interactions
O. Naviliat-Cuncic et al., LPC CaenO. Naviliat-Cuncic et al., LPC Caen
e+
e
nucleus
Vud
0+0+ = 0.97418(26)
VusK = 0.2254(21)
VubB = 0.00367(47)
= 3071.4 (8) s
2 2 2 2 = + + 0.9967(13= )ui ud us ubi
V V V V
CVC, CKM, exotic currents: 0+ CVC, CKM, exotic currents: 0+ 0+ 0+ decaysdecays
Measurements: - Q value - T1/2 - branching ratios
1.0000(11)
)211)(m)(.(3cos
1)4I(2IQ3h.
Lh.ΔE 21-mm,
θ
-NMR spectroscopy-NMR spectroscopy
h.B.
L0N Ig
-asymmetry in the decay of polarized nuclei in a magnetic field Zeeman splitting related to gI and QS
IM+I
M-I
resonant destruction of the polarization (i.e. -asymmetry) by means of an additional RF magnetic field
h.V. ZZ
QSQe
with and
B0
gI/gI ~ 10-3, QS/QS ~ 10-2
complementary technique to collinear laser spectroscopy
suitable for light elements (low QS values)
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
Jn
FEHFS1)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)
N=50N=40
Z=28
Z=40
The physics case for -NMR on polarized beams:
NiZn
nuclear structure towards and beyond 78Ni
Evolution of orbits from Z=40 to Z=28:
ground state spins and momentsof 83Ge, 81Zn, 79Ni and of 81Ge, 79Zn, 77Ni
g-factors can reveal erosion of N=50 shell closure
Produced at
SPIRALII
with d-in
duced fis
sion
Lifetime OK for -NMR studies
GeSe
Kr
G. Neyens et al., KU Leuven
DESIRDESIR building building costscosts
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€
Collinear laser spectroscopy:Manchester 300 k€Orsay 200 k€ Leuven 150 k€
-NMR setup: Leuven 100 k€
-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€
Equipments foreseen at Equipments foreseen at DESIRDESIRLU
MIER
EB
ESTIOL
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 interestedOpened to everyone interested-----------------
http://www.cenbg.in2p3.fr/desir
DESIRDESIR Milestones 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