Eero Rauhala Petteri Pusa Samuli Väyrynen Accelerator Laboratory University of Helsinki Finland

Eero RauhalaPetteri PusaSamuli Väyrynen

Accelerator LaboratoryUniversity of HelsinkiFinlandhttp://beam.helsinki.fi/[email protected]

EXPERIMENTAL STUDIES ON REACTION CROSS SECTIONS FOR 16O(, 0)16O, 2H(p, p0)2H AND 2H(3He, p0)4He

Development of a reference database for ion beam analysis, CRP no. F41023, IAEA, Vienna, Nov. 21-23, 2005

Development of a reference database for ion beam analysis CRP no. F41023IAEA, Vienna, Nov. 21-23, 2005

Arto Nurmela

VTT Information technology MicroelectronicsFinland

1. 4He scattering by oxygen between 8 and 9 MeV for a wide range of scattering angles (first year).

2. Proton scattering by deuterium above 2 MeV at several scattering angles above 90 degrees (second year).

3. 3He + d cross sections around the broad resonance at 0.63 MeV and/or possible further experiments which are considered relevant by the participants of the CRP (third year).

Summary of proposal


Within the CRP, experiments are proposed on reaction cross sections for the reference data base for ion beam analysis.

Measurements of elastic scattering and reaction cross sections for 16O(, 0)16O, 2H(p, p0)2H and 2H(3He, p0)4He will be performed in wide energy and angular regions.

Facilities available


The accelerator facilities at the Accelerator Laboratory of theUniversity of Helsinki comprise• A 5 MV tandem accelerator capable of producing 1-10 MeV

proton, 2-15 MeV helium and heavier ion beams• 500 kV accelerator/implanter for lower ion energies,

equipped with ion sources for most ion species.

The VTT information technology has• A 1.7 MV NEC Pelletron 5SDH2 tandem accelerator capable

of producing He and H beams.

1. Helium - oxygen cross sections

Oxygen is one of the most common constituents and impurities in various materials. Profiling and quantifying of oxygen is difficult with conventional Rutherford backscattering spectrometry.

Using high energy 4He ions between 8 to 9 MeV, the oxygen yield is greatly enhanced, rendering good detection sensitivity of oxygen possible.

The few cross section data available in this region are, however, partly inconsistent and cover only few backscattering angles.



Existing data from the IBANDL data base:

H.-S. Cheng, H. Shen, J. Tang, and F. Yang, Nucl. Instr. and Meth. B83 (1993) 449:16O(, 0)16O, 170o, 2000-9000 keV

J. John, J.P. Aldridge, and R.H. Davis, Phys. Rev.

181 (1969) 1455:16O(, 0)16O, 165.7o, 5030-12450 keV

Feng et al., 1994 (not published):

16O(, 0)16O, 165o, 2050-9010 keV

W.E. Hunt, M.K. Mehta, and R.H. Davis, Phys. Rev. 160 (1967) 782:16O(, 0)16O, 158.6o, 6180-10400 keV



Data from IBANDL




Measurement plan

Samples:• Tantalum oxide on carbon foil, grown by ALD

• Analysis by 900 keV 3He backscattering: NtO/NtTa = 2.846 2%

Measurements:• Several detectors, angular region 170o – 90o

• Energy region 8 – 9 MeV

2. Proton scattering by deuterium


Hydrogen plays a decisive role in shaping the properties of many materials.

The D(p, p) elastic scattering cross section experiments from below 1 MeV to several MeV at several scattering angles above 90o will be measured.

These experiments will be done in collaboration with other institutes:

• University of Paris, Dr. Ian Vickridge• Max Planck Institute, Dr. Matej Mayer • Institute of Physics and Power Engineering, Obninsk, Dr. Alex

Gurbich



Example of proton backscattering by deuterium:3.6 MeV p on 200 nm ErD2

0 200 400 600 800 1000 12000

2000

4000

6000

8000

10000

12000

14000

16000

CHANNEL

YIE

LD

3.6 MeV p -> ErD2|Mo

D

OEr

Mo

D

O Mo Er

3.6 MeV pon ErD2 / Mo

0 200 400 600 800 1000 12000

2000

4000

6000

8000

10000

12000

14000

16000

CHANNEL

YIE

LD

3.6 MeV p -> ErD2|Mo

D

OEr

Mo

D

O Mo Er

3.6 MeV pon ErD2 / Mo



R.A. Langley (1976) in Proc. Int. Conf. on Radiation Effect and Tritium Technology for Fusion Reactors, vol IV, (J.S. Walson and F.W. Wiffen, eds.), p.158. Conf. 750989, US Dept. of Commerce, Springfield, VA.

Data from IBANDL



D.C. Kocher and T.B. Clegg, Nucl. Phys. A132 (1969) 455.

Angular distributions of differential cross sections measured from enriched gas targets for proton energies between 1 and 10 MeV.

Coordinate system definition uncertain!



SIMNRA discussion (by M. Mayer)

http://www.rzg.mpg.de/~mam/ CrossSection.html#Discussion

“Both data sets were digitised from the same publication by Langley, where he showed the same data in mb/sr in the center-of-mass system and as ratio-to-Rutherford in the laboratory system. Unfortunately, these data disagree by a factor of about 4.”

Figure from SIMNRA

“A similar uncertainty is present for the scattering angle, which is described as 165° center-of-mass angle (equals to 151° lab angle) in one publication, and as 165° lab angle in another publication.”


SIMNRA suggests the higher data set is correct for 165o !



Measurement plan

Samples (provided by M. Mayer):• Amorphous deuterated hydrocarbon film (200 nm) on carbon foil, with 7 nm Au on top

• Analysed with about 4.4% accuracy by 800 keV 3He backscattering and the D(3He, 4He)p reaction:

Mean D content relative to Au:Set 1: NtD / NtAu = 24.72 1.7% Set 2: NtD / NtAu = 24.90 0.9%

Measurements:• Several detectors, angular region: 170o – 90o

• Energy region: From below 1 MeV – several MeV

3. 3He + d system



Differential cross section data:

V.Kh. Alimov, M. Mayer, J. Roth. NIM B, in press. 2H(3He, p0)4He, 135o, 550-6000 keV.

J.W. Mayer and E. Rimini Ion Beam Handbook for Material Analysis, Pergamon N.Y. (1978) 126. 2H(3He, p0)4He, 135o, 550-6000 keV.

Total cross section data:

W. Moller and F. Besenbacher, Nucl.Instr.Meth., 168(1980), 11. 2H(3He, p0)4He, 360.00o, 210-2160 keV.

T.W. Bonner, J.P. Conner and A.B. Lillie, Phys.Rev., 88(1952), 473. 2H(3He, p0)4He, 360.00o, 280-2390 keV.


Data from IBANDL

3. 3He + d system


3. Other possible measurements

Depending on the input from the data evaluations and the RCM’s, measurements considered relevant/valuable can be included in the experiments for the third year.

Eero Rauhala Petteri Pusa Samuli Väyrynen Accelerator Laboratory University of Helsinki Finland

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