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