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The SPES project: a The SPES project: a first step towards first step towards
EURISOLEURISOLM. CinauseroM. Cinausero
Laboratori Nazionali di LegnaroLaboratori Nazionali di Legnaro
On behalf of the SPES On behalf of the SPES collaborationcollaboration
Outline of the talkOutline of the talk
The project objectivesThe project objectives
The project status The project status
Physics to be addressed Physics to be addressed
ConclusionsConclusions
PRODUCTION OFPRODUCTION OFn-RICH ISOTOPES:n-RICH ISOTOPES:
80 < A < 160 80 < A < 160
RIB INTENSITY:¤ 1013 fissions/s¤ 107-109 rare ions/s on experimental sites¤ RIBs energy: 9-11 MeV/u
SPES: A mid-term ISOL n-rich SPES: A mid-term ISOL n-rich FacilityFacility
Multi-sliceMulti-slice
UCUCx x TargetTarget
p @ 40 p @ 40 MeVMeV
I = 0.2 mAI = 0.2 mA
~1013Fiss./s
SPES LAYOUT AT LNL SPES LAYOUT AT LNL 60x83 m2
Low energy RIB
experiments
Existing Buildings
Ion source
Bunching RFQ
Charge breeder
isobar separation
HV platform
ALICE platform
SRFQPIAVE
TRIPS +TRIPS +TRASCO TRASCO
RFQRFQ
DriverDriverAreaArea
Neutron Neutron facilitiesfacilities
(irradiatio(irradiation,n,
BNCT)BNCT)
TargetTargetAreaArea
TargetLaboratories
Area forpossibledeveloping
IBA Cyclone 70IBA Cyclone 70
The Proton DriverThe Proton DriverCommercial Cyclotron: Beams: H- / D- Variable energy: 15 MeV 70 MeV Extraction system: Stripper for H- / D- Performances: 750µA, 2 beam exits
LINAC: Beam: protons Energy: ~ 43 MeV Av. beam current: up to 0.5 mA Beam pulse length: 200 s Repetition rate: 50 Hz RF frequency: 352.2 MHz
ECR source(TRIPS)
RFQ(room temp.)
DTLCERN Linac4 basic design
(permanent magnet quadrupole focusing)
NeutronFacilities
p @ 42 MeV, up to 20A
SPESHRIBF
The Target Prototype The Target Prototype
SiC Pellets Characteristics:SiC Pellets Characteristics:- Pellets diameter: 13 mmPellets diameter: 13 mm- Pellets distance: 1 mmPellets distance: 1 mm- density: 3.07 g/cmdensity: 3.07 g/cm33
- emissivity: 0.85 emissivity: 0.85 (MEASURED!)(MEASURED!)- specific heat: 670 J/(kg m K)specific heat: 670 J/(kg m K)- conductivity: 30 W/(m K)conductivity: 30 W/(m K)- melting point: 2300°Cmelting point: 2300°C
INITIAL PELLETS INITIAL PELLETS MATERIAL: commercial MATERIAL: commercial
SiC SiC
Type: Hexoloy SG SiC(from “Saint Gobain”)
SCALE 1:5 SCALE 1:5
On-Line Test at HRIBF On-Line Test at HRIBF
1)1) Power dissipation testPower dissipation test2) Production test2) Production test (Yields of exotic Al isotopes )(Yields of exotic Al isotopes )
Data from pyrometer readingwith and without sheldingof the target box.
Aluminum I sotopic Chain
10
100
1000
10000
100000
25.5 26 26.5 27 27.5 28 28.5 29 29.5
Mass (amu)Co
unts
/s
2 microA, 1800°C
5 microA, 1800°C
10 microA, 1800°C
12 microA, 1800°C
2 microA, 1600°C
HRIBF typical exp. conditions
Net Net yield gainyield gain with with SPES configuration!SPES configuration!
Dumper Temperature measurement
600
900
1200
1500
1800
2100
2400
0 100 200 300 400 500 600 700 800
Heater Current [A]
T [°C]
Experimental - Without shields
Experimental - With shields
FEM - Without shields
FEM - With shields
Poly. (Experimental - With shields)
Poly. (Experimental - Without shields)
without shield
with shieldwith shield
UCx pellets productionUCx pellets production
Target System Layout Target System Layout
Front-end: SPES design
Heater: SPES®Target: SPES® (Ø = 4 cm)
SPES Heater
SPES Chamber(made by ALCA-Schio)
Target HandlingTarget Handling
Storage
Movimentation
Beam intensities (I)Beam intensities (I)
1-step: p 40 MeV 0.2 mA on multi-slice direct target (25 gr UCx)
Release times considered:1-step 2 s, 2-step 40 s
Sn isotopes
1,00E+09
1,00E+10
1,00E+11
115 117 119 121 123 125 127 129 131 133 135 137
1-step
2-step
In-target production from M.C.
Beam intensities evaluated considering release, ionization and reaccelerationefficiencies
2-step: d 40 MeV 2mA on thick 12C converter + UCx target (800 gr)
N-rich
1013 fissions/sec
Sn isotopes
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
110 115 120 125 130 135 140
yiel
d (p
ps)
DirectTarget
2step
N-rich
Sn isotopes
Effusion-diffusion effect on isotopes releaseEffusion-diffusion effect on isotopes release
Beam on Target
1.00E+00
1.00E+01
1.00E+02
1.00E+03
1.00E+04
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
70 80 90 100 110 120 130 140 150
mass
inte
nsi
ty (
sec-
1)
Series1
132Sn
Ga
KrSr
AgIn Sn Cs
ionization efficiencies: (1+) 90% and (n+) 12% for Kr and Xe, (1+) 30% and (n+) 4% for Zn, Sr, Sn, I, Cd
Transport efficiency 50%
Beam intensities (II)Beam intensities (II)
When available the intensities are calculated on the basis of the beam intensities delivered at HRIBF(2005)
mass
Estimated beam intensities available for experiments
Shell evolution (I)Shell evolution (I)Element formation in r-process: quenching of shell-structure?Pfeiffer et al., Z. Phys. A357 (1997) 235
Experimenlal Signatures:
Energies of the excited levels
Nucleon Separation energies
Transition matrix elements
Shell evolution (II)Shell evolution (II)
Extend the level scheme at higher states and toward the n-drip line with the more intense and energetic SPES beams via tranfer reactions
SPES ESTIMATES: up to 138Sn with >105 pps
J. S. Thomas et al. PRC 71, 2005
2H(82Ge,p)83Ge (104 pps) Direct reaction in inverse kinematics
First excited state= (280+ 20) KeV
New studies in progress at HRIBF in the Sn region
(130,132 Sn beams >105 pps)
Critical point symmetries and nuclear phase Critical point symmetries and nuclear phase transitionstransitions
Group Theory : combination of both spatial and isospin symmetries
Harmonic vibrator: U(5)
Deformed symmetric rotor: SU(3)
-unstable nuclei: O(6)
X(5): harmonic vibrator deformed symmetric rotor (F. Iachello PRL 85 2000)
Observables: Energies and lifetimes at j<10h, intra-inter band transition matrix elements
Studied candidates: Gd, Dy (A~150), Ce (A~130)
Spes
1,00E+06
1,00E+07
1,00E+08
1,00E+09
1,00E+10
1,00E+11
84 86 88 90 92 94 96
n-rich Kr isotopes SPES up to 95Kr >107 pps
see e.g. R.M. Clark et al., PRC 68 (2003)
Limiting temperature studies (I)Limiting temperature studies (I)
A = 30÷60
A = 60÷100
A = 100÷140
A = 140÷180
A = 180÷240
J.B. Natowitz et al., PRC 65 2002
Limiting temperature T<Tlim the nuclear system can be described as a nuclear drop T>Tlim the thermodynamically equilibrated nuclear drop cannot survive
J.B. Natowitz et al., PRL 89 2002
Infinite nuclear matter EOS
Limiting temperature studies (II)Limiting temperature studies (II)
Going away from stability….. Besprovany Levit PLB 217(1989)
Zhuxia Li, Min Liu PRC 69 2004
86-95Kr + 90Zr = 176-185Os
90-102Sr + 40,48Ca = 130-,150Ce
114-145Xe + 40,48Ca = 154-193W
Possible reactions with SPES
Neutron captureNeutron capture cross section cross section measurementsmeasurements
¤ Activation Facility (cw beam: I = 30mA)- energy range = 1-300 keV- astrophysics interest (TOT -> MACS)- neutron flux ~ 1010 n/s·cm2
- small samples: 1015 atoms/cm2 -> implantation of SPES RIBs (2 weeks)
139Ba(n,)140Ba massive stars SPES flux ≥1010 pps
Maxwellian Neutron Spectrum
kT=48 keV
Neutron production: Neutron production: 77Li(p,n)Li(p,n)
SPES TIME SCHEDULE SPES TIME SCHEDULE (CYCLOTRON SOLUTION)(CYCLOTRON SOLUTION)
2007 2008 2009 2010 2011 2012 2013
Facility design
Target prototypes
Autorization to construction
Building construction
Target installation and comm
Completion of TRASCO RFQ
Installation and comm of TRASCO RFQ
Ciclotron construction
Installation and comm. Cicl.
Alpi preparation for post acceleration
Installation of RIBs transfer lines and spectrometer
Complete commissioning
ConclusionsConclusions
The construction phase of the SPES facility has started
Definition of key experiments under study
Thanks for your attention!
SPES COLLABORATION SPES COLLABORATION INFN Laboratori Nazionali di Legnaro, Italy:
A.Andrighetto, M.Barbui, G.Bassato, G.Bisoffi, S.Carturan, F.Cervellera, M.Cinausero, P.Colautti, M.Comunian, L.Corradi, A.Dainelli, G.de Angelis, E.Fagotti, E.Fioretto, M.Giacchini, F.Gramegna, M.Lollo, G.Maggioni, P.Mastinu, A.Palmieri, A.Pisent,
M.Poggi, G.Prete, V.Rizzi, A.Stefanini, M.Tonezzer, D.Zafiropoulos
ENEA, Bologna and Faenza, Italy: C.Antonucci, S.Cevolani, C.Petrovich
Dipartimento di Ingegneria Meccanica, University of Padova, Italy:L.Biasetto, P.Colombo, M.Manzolaro, G.Meneghetti
Dipartimento di Costruzione Trasporti,Ingegneria, University of Padova, Italy:C.E. Majorana, V. Salomoni
INFN Laboratori Nazionali del Sud, Catania, Italy:L.Celona, F.Chines, G.Cuttone, G.E.Messina, M.Re, D.Rizzo
Dipartimento di Scienze chimiche, University of Padova, Italy: P.Di Bernardo, P.Zanonato, L.Piga
INFN-Bari, Italy: A.Variale
INFN-Pavia and University of Pavia, Italy: P.Benetti
Dipartimento di Ingegneria Meccanica, University of Trento, Italy: I. Cristofolini, M. De Cecco, R. Oboe,
LNL InstrumentationLNL Instrumentation
ION SOURCE AND RFQ ION SOURCE AND RFQ
Requirement Status
Beam energy 80 keV 80 keV
Total current 70 mA 60 mA
Proton fraction 90 % 85 %
Microwave power frequency
<2 kW at 2.45GHz
0.3-1 kW at 2.45 GHz
Duty factor 100 % (dc) 100 % (dc)
Beam emittance<0.2 π mm
mrad~0.07 π mm
mrad
Reliability ~100 %90 % at 30
mA
Gas flow <2 sccm 0.4-0.6 sccm
TRIPSTRIPS: : developeddevelopedat LNS, now at LNS, now operating at LNL operating at LNL
RFQRFQ: 6 modules: 6 modules- 2 completed, 4 - 2 completed, 4 waitingwaiting the brazing at CERN -the brazing at CERN -
¤¤ Energy: 5 MeV Energy: 5 MeV¤ Current:up to 35 mA¤ Current:up to 35 mA¤ Operation: cw and pulse ¤ Operation: cw and pulse modemode
NEUTRON FACILITIES: BNCTNEUTRON FACILITIES: BNCT
The in-air thermal neutron flux level at SPES-BNCT
is 2∙109cm-2s-1 at beam port
Reaction: 10B(n,)7Li (n capture : 3837 barn)
The method: 10B is chemically carried in the tumour bulk (skin melanoma).The charged particles produced in the reaction deposit their energy inside the cell volume.BNCT is a highly selective method to destroy cells in the tumor tissue.
ALPI ACCELERATORALPI ACCELERATOR
ALPI: a Superconductive
Linear Accelerator for Heavy Ionsbased on QW resonators
(Injector:Injector: PIAVE PIAVE)
YEAR 2006 2007 2008 2009 2011
Eacc
(MV/m)
CR03CR04-CR06CR07-CR20
03
3.6
03.54.2
63.54.2
66
4.2
66
4.2
Energy
(MeV/A)
132Xe20+
132Xe26+
132Sn20+
6.1 7.1 7.911 11
9.1
THERMO-MECHANICALTHERMO-MECHANICALCALCULATIONS I CALCULATIONS I
Proton Beam Power: 8 kW.Fixed Box Temperature: T=2000oC.
Maximum Temperature
2000
2100
2200
2300
2400
0 1 2 3 4 5 6 7 8 9 10 11 12
element
°C
UCx Melting point:
2350°CDEPOSITION IN THE TARGET:1)1) 0.19 kW in the window;2)2) 4.1 kW in the 7 UCx disks;3)3) 1.7 kW into the 3 dump disks; 4)4) 2.2 kW lost outside the disks (due to proton scattering).
TOTAL: 8.19 kW
145 W/g: SAME POWER 145 W/g: SAME POWER DENSITY OF DENSITY OF
HRIBF TARGET HRIBF TARGET
Power Deposition
0
1
2
3
4
5
1 2 3 4
kW
MC calculations (MCNPX code, ORNL model)
(Benchmarked by ANSYS calculations)
THERMO-MECHANICALTHERMO-MECHANICALCALCULATIONS II CALCULATIONS II
Thermal stress (equivalent stress, Pa) arises for differential expansion due to non-uniform temperature distribution.
Thermal stress
components in the 7th disk
(the worst conditions):
static calculations
Thermal analysisThermal analysis based on power deposition data:heat is removed bythermal radiation (fromdisks to box, fixed at T=2000°C, and thenfrom box to chamber).
1
MNMX
XY
Z
Target SPES
.797E+07.291E+08
.502E+08.714E+08
.925E+08.114E+09
.135E+09.156E+09
.177E+09.198E+09
FEB 11 200723:44:17
NODAL SOLUTION
STEP=1SUB =1TIME=1SEQV (AVG)DMX =.571E-03SMN =.797E+07SMX =.198E+09
Disks:
1 st 2 nd 3 rd 4 th 5 th 6 th 7 th
ANSYS Code
Beam
Stress components on the c surface
-150
-100
-50
0
50
100
150
200
250
0 2 4 6 8 10 12 14 16 18 20 22
r [mm]
stress [MPa]
radial stress
circumferential stress
axial stress
equivalent stress
Critical value ~ 200MPa
RELEASE CALCULATIONS RELEASE CALCULATIONS
GEANT4GEANT4 (NIMA506(2003),250)Free effusion calculation with Adsorption Desorption on the wallsThe disks are slabsThe temperature is T = 2200 K.
RIBORIBO(M. Santana Leitner Ph.D Thesis) In-grain Diffusion, Inter-grain Effusion, Free Effusion with Adsorp. Desorpt. on the walls, Ionization.The disks may be slabs, powder or fibers The temperature is T = 2200 K.
Cross check with Two Codes :
Geant4 & Ribo
GOOD GOOD AGREEMENT!!
AGREEMENT!!
CALCULATION CONDITIONS:
Container : cylindrical tube
(radius = 4 cm; length = 24 cm)
7 UCx Disks: radius = 3 cm,
th. = 1 mm ( = 2.5 g/cm3)
3 Graphite Disks: radius =3 cm,
th. = 0.2 mm ( = 1.75 g/cm3)
Graphite window: radius =4 cm,
th. = 0.4 mm
Spacing Between disks: 2 cm
Exit length: 12 cm
Effusion
Sticking time (s)
Diffusion
T 1/2 (s)
RESULTSRESULTS:
for 132Sn isotope
¤ Total Effusion time : 0.41 ± 0.02 s Inter-grain eff.: <path> ~ 1 50m <Coll.> ~ 2700 Free effusion: <path> ~ 1.5 m <Coll.> ~ 105
¤ Total Release time: 1.5 ± 0.5 s
with: mean free path = 15 m sticking time = 10-6 s D = 1 s(from ISOLDE data)
Steps
Activity (Bq)
Dose * gram (Sv/h)
Total Dose (Sv/h) at 1 m
Total Dose (Sv/h) at 2 m
Total Dose (Sv/h) at 2 m with 2cm
of lead
IRRADIATION (1013 f/s)
1 Days 1.50E+13 6.20E-02 1.77E+00 4.43E-01
4 Days 1.70E+13 6.70E-02 1.92E+00 4.79E-01
7 Days 1.80E+13 6.80E-02 1.94E+00 4.86E-01
14 Days 2.00E+13 7.30E-02 2.09E+00 5.22E-01
COOLING
1 Secs 2.00E+13 7.26E-02 2.08E+00 5.19E-01 5.19E-02
1 Days 3.33E+12 6.82E-03 1.95E-01 4.88E-02 4.88E-03
3 Days 1.78E+12 3.85E-03 1.10E-01 2.75E-02 2.75E-03
14 Days 6.67E+11 1.44E-03 4.12E-02 1.03E-02 1.03E-03
30 Days 1.78E+11 3.85E-04 1.10E-02 2.75E-03 2.75E-04
90 Days 5.00E+10 8.36E-05 2.39E-03 5.98E-04 5.98E-05
10 Years 6.22E+08 5.94E-07 1.70E-05 4.25E-06 4.25E-07
100 Years 1.22E+08 1.01E-07 2.89E-06 7.24E-07 7.24E-08
TARGET HANDLINGTARGET HANDLING
- 14 days of irradiation, 14 days of cooling
- After deposition of the chamber in a lead box it can be manually handled
- handling for 5 minutes –> total dose to operator = 83 Sv
- foreseen 25 runs/year -> Total dose amount for 1 year = 2 mSv (far from 20 mSv max dose/year)
PELLETS CHARACTERIZATION PELLETS CHARACTERIZATION STRUCTURALSTRUCTURAL THERMO-MECHANICALTHERMO-MECHANICAL
SEM PICTURES
EDAX INSPECTION Compositional information(not quantitative)
Sinthering degree(surface)
XRD Analysis (at differentStages of Preparation)
CARBURIZATION SINTERING
Heating Cycle (La)Heating Cycle (La)
1000 1200 1400 1600 1800 20000.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
SiCA (hexagonal, bulk) SiCG (hexagonal, bulk) SiC xycarb (cubic, porous) Al2O3 Graphite (fine) LaCx
T (°C)
Emissivity MeasurementsEmissivity Measurements
FIRST EMISSIVITY FIRST EMISSIVITY MEASUREMENT AT 2000°C MEASUREMENT AT 2000°C OF SiC AND LaCx AT LNL OF SiC AND LaCx AT LNL
LNL LNL furnace furnace
SECONDARY BEAM SECONDARY BEAM TRANSPORTTRANSPORT
ProtonDriver
UCxTarget
Low res. mass
selection
High res. mass
selection
ChargeBreeder
PIAVE+ ALPI
X+1 X+n
BunchingRFQ- Energy out of the TIS system: 40-60 keV
- Separation: according to the M/q ions ratio- Along the beam line: electrostatic quadrupoles and deflectors- Low resolution mass separator: M/M = 300- High resolution mass separator: M/M = 15 000 (low energy exp. areas)
Proton Proton beambeam
RIB beamRIB beam
Target Target BunkerBunker
Handling zoneHandling zone
ServiceServicess
Target Building: preliminaryTarget Building: preliminary
RIB beamRIB beamRIB beamRIB beam