ISOLDE Workshop and Users meeting 2011
Nanostructured Calcium Oxide Targets for the Production of Argon Beams
João Pedro Ramos7th of December 2011
Dr. Thierry Stora
Prof. Ana Senos
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Overview CaO Targets at ISOLDE:
Overview and Issues
Material Study Characterization Techniques Material Synthesis Reactivity with Air Sintering Kinetics
Online Tests: Yields
Future Work
2/15
ISOLDE Application Target Production Target Handling Target Operation
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
CaO Target Main Issues:
Unstable Yields Low since the beggining Drop over time
Turrion, M.; Urszula, H.-I. ISOLDE Yield Database. https://oraweb.cern.ch/pls/isolde/query_tgt (accessed December 1st, 2011)Shift numbers by courtesy of Magdalena Kowalska, Physics Coordinator at ISOLDE, CERN.
Overview
3/15
1 to 2 Targets built every year
Shifts for the last 5 years
0 5 10 15 20 25 30 35 40 45 501E+0
1E+1
1E+2
1E+3
1E+4
1E+5
1E+6
1E+7
1E+8
Isotopes of Interest
Argon PSB
Carbon PSB
Helium PSB
Neon PSB
Argon SC
Carbon SC
Helium SC
Nitrogen SC
Neon SC
Mass Number
Yie
ld (
ions/
C)
Microstructure relatedMaterial study needed!
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Material Characterization Best material for best release
properties: High porosity (>30%) High pore size (>100nm) Nanometric grain (<100nm)
Stora, T. et al., Nanostructured Target for Isotope Production, WO 2010/034364 A1, 2010.
Material Study
4/15
10 20 30 40 50 60 70 802θ(o)
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Material Synthesis
Material Study
5/15
500 550 600 650 700 750 800 850 900 950 100030
35
40
45
50
55
30
35
40
45
50SSA
Temperature (oC)
Surf
ace A
rea (
m2/g
)
Cry
sta
llit
e S
ize (
nm
)
Nanostructured material
35 – 40nm
High Open Porosities (~47%)
Pore Size ~20nm
CaO
CaCO3
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Material Synthesis
Material Study
6/15
500 550 600 650 700 750 800 850 900 950 100030
35
40
45
50
55
30
35
40
45
50SSA
Temperature (oC)
Surf
ace A
rea (
m2/g
)
Cry
sta
llit
e S
ize (
nm
)
Nanostructured material
35 – 40nm
High Open Porosities (~47%)
Pore Size ~20nm
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Target ProductionOld Process
Temperature up to 1200oC Pyrometer to control T No defined heating and
cooling rates
ISOLDE Application
7/15
New Process
Temperature up to 800oC Thermocouple to control T ~10oC/min (Heating and
Cooling rates)
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
0.0 10.0 20.0 30.0 40.0 50.0 60.00%
10%
20%
30%
40%
50%
60%
59m2/g
Time (min)
Mate
rial H
ydra
ted
Reactivity to Air
Higher Sintering of CaO produced from Ca(OH)2
Irreversibility in terms of microstructure
8/15
Material Study
0.9 to 1.2% per min
As produced: 59m2/g
Left at Air for 2 days: 9m2/gTT at 800ºC for 20 min: 28m2/g
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Target Handling
9/15
No care with respect to hydration was taken before. Glove Box (Argon atm) Single Batch Preparation
Prevents Hydration Enhances safety
(nanomaterial)
No traces of Ca(OH)2 on XRD were detected!
ISOLDE Application
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Sintering Kinetics CaO Pellets with 60% porosity were pressed
10/15
0 100 200 300 400 500 60025
30
35
40
45
50
Time (min)
SSA
(m
2/g
)
Starting Powder = 59m2/g
1000oC
1100oC
1200oC
Material Study
1200o
C
3min 2h 10h
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Target Operation
11/15
Old Settings
T up to 1200oC 3x1013ppp
Avoid Nanostructure degradation.
New (Safe) Settings
T up to 800oC 8x1012ppp
ISOLDE Application
25 to 40 m2/g 40 to 70nm 33% Porosity
(~11nm)
~4 m2/g 0.3 to 0.5m 9% Porosity
(~9nm)
>40 m2/g <45nm 47% Porosity
(~20nm)
>38m2/g <45nm 47% Porosity (~20nm)Te
mp
era
ture
eff
ect
on
ly!
Eff
ect
of
Pro
ton
s is
un
kn
ow
n!
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Target CaO #469 (VADIS)
Yields on 31,32Ar measured by ISOLDE experiment IS476 – H. Fynbo and B. Blank.Turrion, M.; Urszula, H.-I. ISOLDE Yield Database. https://oraweb.cern.ch/pls/isolde/query_tgt (accessed December 1st, 2011)TRIUMF. ISAC Yield Measurement. http://www.triumf.info/facility/research_fac/yield.php (accessed December 5th, 2011)GANIL. SPIRAL Beams. http://pro.ganil-spiral2.eu/users-guide/accelerators/spiral-beams (accessed December 5th, 2011)
Online Tests
12/15
Isotope T(ºC)Yield
(ions/C)Database(ions/C)
6He 610 2.3E+6 2.6E+610C (CO) 705 6.1E+5 5.3E+515C (CO) 705 7.0E+3 6.2E+319Ne 610 9.6E+6 7.6E+6
30.5 31 31.5 32 32.5 33 33.5 34 34.5 35 35.51E+0
1E+1
1E+2
1E+3
1E+4
1E+5
1E+6
1E+7
1E+8
1E+9
5E+0
#123 (1050ºC)
#469 (610ºC)
#408 (>1050ºC)
Argon Mass
Yie
lds (
ions/
C)
(after 8h)
830oC
Comparing ISOLDE Ar beams:Protons per
second
31Ar (15.1ms)
32Ar(98ms)
33Ar(174.1ms)
34Ar(844ms)
35Ar(1.78s)
ISOLDE 6.3E+01 3.6E+03 2.0E+05 2.6E+06 3.0E+08TRIUMF - - 7.0E+02 2.9E+04 6.5E+06SPIRAL 4.4E+00 1.0E+03 9.1E+04 5.0E+06 3.5E+08
More to report on C beams next year (C. Seiffert)
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Yields Over time 31Ar drop on CaO#4085 to 1 ion/C in 8 hours
31Ar measured CaO#469to be 42 ions/C after >80h of operation
32Ar Yield drop, courtesy of Susanne Kreim – ISOLTRAP, ISOLDE, CERN
13/15
Online Tests
0 2 4 6 8 10 12 14 1620%
40%
60%
80%
100%
Decrease of 32Ar Yield on CaO#123 (ISOLTRAP)
Operation Time (h)R
ela
tive 3
2A
r Yie
ld
0 10 20 30 40 50 60 70 80 90 1001E+06
1E+07
1E+08 35Ar yield during operation of CaO#469
Operation time (h)
Yie
ld (
ions/
C)
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Future Work/Plans Further development of CaO target
Tunning the production process Using higher operation temperatures/proton
intensities Study of the proton impact effect on CaO
Possible PhD: Development of nanograined oxide target materials for ISOLDE MgO TiO2 or TiC – Ca beams HfO2 – C beams CeO2 – Se beams ThO2 – gains on metalic beams
Future Work
14/15
Jo
João Pedro Ramos
ISOLDE Workshop and Users meeting 2011Nanostructured Calcium Oxide Targets for the Production of Ar Beams
Thank you!Comments and questions?
15/15
Acknowledgments
Ana SenosThierry StoraAlexander GottbergTânia MendonçaBernard CrepieuxMagdalena KowalskaMichał CzapskiChristoph SeiffertMartin BreitenfeldtGonzalo IzquierdoMonika StachuraMichael OwenJens RoderSusanne KreimThomas Schneider
Top Related