Production of a monochromatic, low energy positron beam using the 11B(p,n)11C reaction

ABSTRACTVacancy-type defects in ion implanted Si were studied by a monoenergetic positron beam. The depth-distributions of the defects were obtained from measurements of Doppler broadening profiles of the positron annihilation as a function of incident positron energy. The results showed that a size of vacany-clusters introduced by 150-keV P+-ion implantation was found to be smaller than that introduced by 2-MeV P+-ion implantation. This was attributed to an overlap of collision cascades in low-energy (150 keV) ion implanted specimens. From isochronal annealing experiments for 80-keV B+- and 150-keV P+-ion implanted specimens, the defected region was removed by 1200 °C annealing, however, for 2-MeV P+-implanted specimen, two-types of oxygen-vacancy complexes were found to coexist even after 1200 °C annealing.

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Modelling the line shape of very low energy peaks of positron beam induced secondary electrons measured using a time of flight spectrometer

Journal of Physics Conference Series ◽

10.1088/1742-6596/791/1/012030 ◽

2017 ◽

Vol 791 ◽

pp. 012030 ◽

Cited By ~ 3

Author(s):

A J Fairchild ◽

V A Chirayath ◽

R W Gladen ◽

M D Chrysler ◽

A R Koymen ◽

...

Keyword(s):

Line Shape ◽

Time Of Flight ◽

Positron Beam ◽

Low Energy ◽

Secondary Electrons

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Radial Expansion of a Low Energy Positron Beam Passing Through a Cold Electron Plasma within a Uniform Magnetic Field

Physics Procedia ◽

10.1016/j.phpro.2015.05.009 ◽

2015 ◽

Vol 66 ◽

pp. 52-58

Author(s):

F.F. Aguirre ◽

C.A. Ordonez

Keyword(s):

Magnetic Field ◽

Uniform Magnetic Field ◽

Positron Beam ◽

Electron Plasma ◽

Low Energy ◽

Radial Expansion ◽

Cold Electron

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Design of a low energy positron beam

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/0168-583x(85)90043-6 ◽

1985 ◽

Vol 12 (3) ◽

pp. 426-429 ◽

Cited By ~ 13

Author(s):

D.T. Britton ◽

P.C. Rice-Evans ◽

J.H. Evans

Keyword(s):

Positron Beam ◽

Low Energy

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Unprecedented intensity of a low-energy positron beam

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2008.05.038 ◽

2008 ◽

Vol 593 (3) ◽

pp. 616-618 ◽

Cited By ~ 72

Author(s):

C. Hugenschmidt ◽

B. Löwe ◽

J. Mayer ◽

C. Piochacz ◽

P. Pikart ◽

...

Keyword(s):

Positron Beam ◽

Low Energy

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Defect-induced magnetism in liquid sodium-exposed stainless steel as studied by Mössbauer and positron annihilation spectroscopic techniques

International Journal of Modern Physics B ◽

10.1142/s0217979217500333 ◽

2017 ◽

Vol 31 (06) ◽

pp. 1750033 ◽

Cited By ~ 5

Author(s):

Alaka Panda ◽

L. Herojit Singh ◽

R. Govindaraj ◽

S. Abhaya ◽

R. Kumar Yadav ◽

...

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Positron Beam ◽

Low Energy ◽

Liquid Sodium ◽

Spectroscopic Techniques ◽

Doppler Broadening ◽

Austenitic Matrix ◽

Hyperfine Parameters ◽

Partial Formation

Detailed Mössbauer studies carried out in liquid sodium (Na)-exposed austenitic stainless steel (SS-316) show that there is a partial formation of ferromagnetically (FM)-ordered ferritic zones in the paramagnetic austenitic matrix. Results of low energy positron beam-based Doppler broadening studies imply the occurrence of vacancy kind of defects in the liquid Na-exposed SS-316. Correlating these results, the partial occurrence of FM-ordered zones in the liquid Na-exposed SS-316 is understood to be due to open volume defects, predominantly that of Ni vacancies occurring at the surface and upto a certain depth of liquid Na-exposed stainless steel. These results are elucidated in terms of hyperfine parameters associated with ferritic zones.

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