positron lifetime
Detection of Neodymium Rich Phase for Development of Coercivity in Neodymium Iron Boron Based Alloys with Submicron Sized Grains Using Positron Lifetime Spectroscopy
... correction. Positron lifetime spec- troscopy was performed using a fast-fast timing coincidence system with a time resolution (FWHM) of 190 ...mCi positron source of 22 Na was put into the sample ...
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Anomalous Temperature Changes of Positron Lifetime and Electrical Resistivity in B2 NiTi Alloys
... The differential scanning calorimetry (DSC) measurements were also carried out in the temperature range between 150 and 350 K for samples cut from the same ingots as were sam- ples for positron lifetime and ...
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S Parameter and Positron Lifetime Studies of Mn Doped Zn1 Xox
... of positron annihilation in nanocrystalline materials is known to be more complex than that in metals and semiconductors because, a fraction of positrons can form a bound state with an ...The positron gets ...
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Influence of Plasma Spray and HVOF Coatings using Advanced Techniques on the Mechanical Properties; A Positron Lifetime Spectroscopy
... the positron lifetime method, the positrons from a Na- 22 radioactive source are injected into the system under investigation and then thermalize very rapidly (≈1-2 ...Subsequently, positron ...
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Surface and Bulk Defects in Cr Mn Iron Alloy Cast in Metal and Sand Moulds: Characterization by Positron Annihilation Techniques
... slow positron beam analysis (DBAR) and conventional positron lifetime analysis (PLS) have been used for the first time to study the defect morphology in terms of defect concentration both at the ...
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Effect of Annealing Temperature on Prepared Nanoparticles Li Ferrite Using Positron Annihilation Lifetime Technique
... A positron implanted in this type of materials can have different lifetimes depending on the electron density at the annihilation ...Thus, positron lifetime spectroscopy can give information about ...
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Microstructural Investigation of PM 355 Nuclear Track Detector Subjected to Low Dose Gamma Irradiation: A Positron Annihilation Lifetime Study
... Positron lifetime measurements were then performed in these SSNTD at room temperature (about 25˚C) as a function of the gamma doses using a standard lifetime spectrometer, details of which are ...
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Point Defect Formation in V 4Cr 4Ti and F82H Irradiated with Fission and Fusion Neutrons
... of positron lifetime measurement for speci- mens irradiated at 673 K are shown in ...mean lifetime increased ...long lifetime of fusion-neutron- irradiated F82H, the defects formed in the ...
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Design and Implementation of a Digital Positron Annihilation Lifetime Spectrometer for Measurements in Graphite
... Upon receiving the START signal, or the signal from the first discriminator that performed the time-pickoff on the 1.28 MeV gamma, the TAC begins charging a capacitor. The capacitor stops charging when the STOP signal is ...
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Defects Investigation in Neutron Irradiated Reactor Steels by Positron Annihialtion (O361)
... reliable lifetime prediction [1]. Since about 1985 positron annihilation spectroscopy (PAS) has been repeatedly used in the study of RPV ...The positron lifetime (PL) technique is a ...
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Positron Annihilation in Perfect and Defective TiO2 Rutile Crystal with Single Particle Wave Function: Slater Type Orbital and Modified Jastrow Functions
... by positron lifetime spectrum, which has many lifetime components depend- ing on a local structure where a positron annihilates with ...accurately lifetime components of a ...
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The effect of oxide precipitates on minority carrier lifetime in n type silicon
... carrier lifetime in n- type samples with substantially different doping levels, but with very similar measured oxide precipitate densities and in- terstitial oxygen ...residual lifetime varies substantially ...
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Vascular reserve in chronic cerebral ischemia measured by the acetazolamide challenge test: comparison with positron emission tomography
... We studied 11 patients with chronic cerebrovascular disease. Their characteristics and diagnoses are presented in Table 1. Nine patients had symptoms of transient is- chemic attack; they were examined at least 2 months ...
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Solid State Reaction and Vacancy Type Defects in Bilayer Fe/Hf Studied by the Slow Positron Beam
... slow positron beam technique have shown that a strong distortion exists and many vacancy-type defects are present in the Hf layers of Cu/Hf multilayers [6] ...slow positron beam ...slow positron ...
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The APEX experiment at JLab. Searching for the vector boson A′ decaying to e+e−
... The multi-foil target is shown in Fig. 4. The incident electron-beam passes through a series of tungsten foils. These foils are arranged so that the outgoing positron- electron pairs produced in one foil do not ...
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Measurement of the W boson mass at the collider detector at Fermilab
... with polar angles i . Conservation of energy and longi- tudinal momentum, p Z , requires $ 2E e 55 GeV if all final-state particles are detected and perfectly mea- sured. Undetected particles that escape through the for- ...
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Lifetime Stories
... In my early thirties, my girlfriend and I took our babies to Guatemala, where we lived for a year and a half in a remote Indian village. It was a magical, wondrous time. Later I moved to Mau’i where for 20 years I kept a ...
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Positron transport in water vapour
... for positron scattering in water vapour is used as the ...for positron transport in water vapour, a multi-term theory for solving the Boltzmann equation has been used to validate the results obtained by a ...
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Investigations of positron impact ionization
... cross-sections of Rapp and Englander-Golden (1965) less the partial cross-section for double ionization (Tawara et al 1985). The measurements of Fromme et al (1986) are smaller than the present results by about 13% at ...
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Minority carrier lifetime in silicon photovoltaics : the effect of oxygen precipitation
... t lifetime data from samples with a high bulk lifetime (low precipitate density) and low bulk lifetime (iron contaminated precipitates with a high density), which suggests that differences between ...
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