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Related papers: Positronium Imaging: History, Current Status, and …

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Study of certain angular correlations in the three-photon annihilations of the triplet state of positronium, the electron-positron bound state, may be used as a probe of potential CP and CPT-violating effects in the leptonic sector. We…

Instrumentation and Detectors · Physics 2020-06-02 Aleksander Gajos

We briefly review the theoretical and experimental results concerning decays of positronium. Possible solutions of the "orthopositronium lifetime puzzle" are discussed. Positronium annihilation into neutrinos is examined and disagreement is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej Czarnecki , Savely G. Karshenboim

In the present ongoing study, we are proposing a prototype model for positron emission tomography detection technology by introduction of a new discriminatory window parameter. It can be a new generation PET detection technique. We…

Instrumentation and Detectors · Physics 2018-12-18 Sunil Kumar , Sushil Singh Chauhan , Vipin Bhatnagar

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

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

We report the first observation of the annihilation of positronium from the 2S state. Positronium (Ps) is excited with a two-photon transition from the 1S to the 2S state where its lifetime is increased by a factor of eight compared to the…

Jagiellonian Positron Emission Tomograph (J-PET) is a multi-purpose detector which will be used for search for discrete symmetries violations in the decays of positronium atoms and for investigations with positronium atoms in life-sciences…

The electron-positron annihilation into two photons is a standard technology in medicine to observe e.g. metabolic processes in human bodies. A new tomograph will provide the possibility to observe not only direct $e^+ e^-$ annihilations…

Quantum Physics · Physics 2017-11-15 B. C. Hiesmayr , P. Moskal

Combined positron and visible light irradiations in the photodynamical therapy (PDT) applications are analyzed. Objectives and goals of PDT are killing or irreversible oxidative damage of pathogenic cells, or rather their cell walls, cell…

Chemical Physics · Physics 2010-01-26 L. V. El'nikova

The Positronium (Ps) system, a bound state of an electron and a positron, is suitable for testing the predictions of quantum electrodynamics (QED), since its properties can be perturbatively calculated to high accuracy and, unlike the…

Nuclear Experiment · Physics 2021-12-21 Elena Perez del Rio

Positron lifetime spectra were measured in liquid water at temperatures between 0c and 50c. The long lifetime of ortho-positronium atoms (o-Ps) determined by electron pick-off in molecular substances decreases smoothly by 10% as the…

Other Condensed Matter · Physics 2009-11-10 Katsushige Kotera , Tadashi Saito , Taku Yamanaka

The J-PET detector, which consists of inexpensive plastic scintillators, has demonstrated its potential in the study of fundamental physics. In recent years, a prototype with 192 plastic scintillators arranged in 3 layers has been optimized…

Positron Emission Tomography (PET) is an imaging technique which can be used to investigate chemical changes in human biological processes such as cancer development or neurochemical reactions. Most dynamic PET scans are currently analyzed…

Applications · Statistics 2014-11-11 Ci-Ren Jiang , John A D Aston , Jane-Ling Wang

Positron Emission Tomography (PET) is a medical imaging modality that utilizes positron-emitting isotopes, such as Ga-68 and F-18, for many diagnostic purposes. The positron annihilates with an electron from the surrounding area, creating…

Positron Emission Tomography (PET) is a powerful medical imaging technique, but the design and evaluation of new PET scanner technologies present significant challenges. The process is typically divided into three major stages: 1. detector…

Instrumentation and Detectors · Physics 2026-01-30 J. Renner , J. J. Gómez-Cadenas , R. Soleti

Electron antineutrinos are detected in organic liquid scintillator based neutrino experiments by means of the inverse beta decay, producing both a positron and a neutron. The positron may form a bound state together with an electron, called…

Instrumentation and Detectors · Physics 2019-02-20 Mario Schwarz , Sabrina M. Franke , Lothar Oberauer , Miriam D. Plein , Hans Th. J. Steiger , Marc Tippmann

A model describing the relationship between the ortho--positronium lifetime and the volume of a void, located in a synthetic zeolite, is analyzed. Our idea, which allows us to take into account the effects of temperature, comprises the…

Chemical Physics · Physics 2009-11-10 Abel Camacho

In X-ray imaging, photons are transmitted through and absorbed by the subject, but are also scattered in significant quantities. Previous attempts to use scattered photons for biological imaging used pencil or fan beam illumination. Here we…

The Jagiellonian Positron Emission Tomograph (J-PET) is a novel de- vice being developed at Jagiellonian University in Krakow, Poland based on or- ganic scintillators. J-PET is an axially symmetric and high acceptance scanner that can be…

The precise measurements of the Compton scatterings of photons originating from the decay of positronium atoms can reveal information about their polarizations. J-PET detector is constructed of 192 plastic scintillators and is unique to…

Instrumentation and Detectors · Physics 2020-01-29 Sushil K. Sharma , Nikodem Krawczyk , Juhi Raj