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Related papers: Nanoporosity imaging by positronium lifetime tomog…

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Sub-micron defects represent a well-known fundamental problem in manufacturing since they can significantly affect performance and lifetime of virtually any high-value component. Positron annihilation lifetime spectroscopy is arguably the…

Positronium atoms (Ps) are widely used as a probe to characterize voids or vacancies in non-metallic materials, where Ps annihilation lifetime is strongly modified by pickoff, depending on the size of the trapping cavity and on the…

Strongly Correlated Electrons · Physics 2022-05-25 Giacomo Marlotti Tanzi , Giovanni Consolati , Fabrizio Castelli

The Jagiellonian Positron Emission Tomograph (J-PET) is the first PET device built from plastic scintillators. It is a multi-purpose detector designed for medical imaging and for studies of properties of positronium atoms in porous matter…

Exploiting small angle X-ray and neutron scattering (SAXS/SANS) on the same sample volume at the same time provides complementary nanoscale structural information at two different contrast situations. Compared with an independent…

Positron physics touches on a wide-ranging variety of fields from materials science to medical imaging to high energy physics. In this paper we present the development of a flexible positron annihilation spectrometer appropriate for the…

Physics Education · Physics 2018-08-01 Jason Engbrecht , Nathaniel Hillson

Accurate characterization of the asymmetry parameter g is of crucial importance for many radiative transfer and climate models. Here, we present our portable light scattering (PLS) device which is designed for in situ, real-time, and…

Atmospheric and Oceanic Physics · Physics 2019-05-01 Yuli W. Heinson , Christopher M. Sorensen , Rajan K. Chakrabarty

The objective of this work is to showcase the ortho-positronium lifetime as a probe for soft-tissue characterization. We employed positron annihilation lifetime spectroscopy to experimentally measure the three components of the positron…

Purpose: Measuring the ortho-positronium (oPs) lifetime in human tissue bears the potential of adding clinically relevant information about the tissue microenvironment to conventional positron emission tomography (PET). Through phantom…

Positron emission tomography, like many other tomographic imaging modalities, relies on an image reconstruction step to produce cross-sectional images from projection data. Detection and localization of the back-to-back annihilation photons…

Positronium-based imaging requires realistic modelling of positronium (Ps) decay in matter. We introduce a modular Ps decay model implemented in GATE 9.4 and GATE 10, enabling the definition of an arbitrary number of decay channels…

Results of Positron Annihilation Lifetime Spectroscopy (PALS) and microscopic studies on simple microorganisms: brewing yeasts are presented. Lifetime of ortho - positronium (o-Ps) were found to change from 2.4 to 2.9 ns (longer lived…

Positronium imaging was recently proposed to image the properties of positronium atoms in the patient body. Positronium properties depend on the size of intramolecular voids and oxygen concentration; therefore, they deliver information…

Nanoporous anodized alumina oxide have been used as templates for obtaining nanomaterials such as nanowires, which exhibit interesting electronic, magnetic and optical properties. This article presents how the regularity of the spatial…

Surface-enhanced Raman spectroscopy (SERS) is a powerful tool for vibrational spectroscopy as it provides several orders of magnitude higher sensitivity than inherently weak spontaneous Raman scattering by exciting localized surface plasmon…

The J-PET tomograph is constructed from plastic scintillator strips arranged axially in concentric cylindrical layers. It enables investigations of positronium decays by measurement of the time, position, polarization and energy deposited…

Based on density functional theory (DFT), the formation energies of intrinsic vacancy defects (VC, VSi, and VSi+C) and oxygen-related defects (OC, OSi, OCVSi, and OSiVC) in 3C-SiC are systematically investigated. The results indicate that…

Materials Science · Physics 2026-02-10 Yi Zhao , Hongtao Zhang , Qiang Li , Xian Tang , Guodong Cheng

Celestially, Positronium (Ps), has only been observed through gamma-ray emission produced by its annihilation. However, in its triplet state, a Ps atom has a mean lifetime long enough for electronic transitions to occur between quantum…

Instrumentation and Methods for Astrophysics · Physics 2021-06-29 J. Gordon Robertson , Simon Ellis , Qingshan Yu , Joss Bland-Hawthorn , Christopher Betters , Martin Roth , Sergio Leon-Saval

The thermal stability of nanocrystalline (nc) Al has been studied by means of positron lifetime spectroscopy and X-ray diffraction (XRD), prepared by compacting nanoparticles under high pressures. Those nanoparticles were produced by the…

Materials Science · Physics 2015-02-06 Xian-Bao Song , Zhu Wang , Peng-Fei Tai , Feng-Shou Tian , Liang-Liang Liu

Conventional optical components are limited to size-scales much larger than the wavelength of light, as changes in the amplitude, phase and polarization of the electromagnetic fields are accrued gradually along an optical path. However,…