Results 101 to 110 of about 4,639 (219)
Optical Spectroscopy of Molecular Positronium
Physical Review Letters, 2012 We report optical spectroscopic measurements of molecular positronium (Ps(2)), performed via a previously unobserved L=1 excited state. Ps(2) molecules created in a porous silica film, and also in vacuum from an Al(111) crystal, were resonantly excited and then photoionized by pulsed lasers, providing conclusive evidence for the production of this ...
Cassidy, DB +3 more
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Studies of discrete symmetries in decays of positronium atoms
EPJ Web of Conferences, 2018 A positronium - a bound state of electron and positron - is an eigenstate of parity and charge conjugation operators which decays into photons. It is a unique laboratory to study discrete symmetries whose precision is limited, in principle, by the ...
Czerwiński Eryk +31 more
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Testing the weak equivalence principle with positronium by Rydberg-atom interferometry
New Journal of PhysicsWe describe an experimental scheme wherein phase shifts induced by the gravitational field of the Earth on atoms in superpositions of Rydberg states with large static electric dipole moments can be observed by matter-wave interferometry.
L R McCaul, D B Cassidy, S D Hogan
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Nukleonika, 2015 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 component) for ...
Kubicz Ewelina +28 more
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Photodetachment of the Positronium Negative Ion with Excitation in the Positronium Atom [PDF]
Atoms, 2018 Lyman-α radiation ( 2 P → 1 S ) has been seen from astrophysical sources and the sun. The line shape of this transition has been measured recently in Ps atoms both inside and outside a porous silica target. In the photodetachment of Ps−, the residual Ps atom can be left in the 2P state instead of the 1S state giving rise to positronium Lyman ...
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Positronium formation at Si surfaces
, 2018 Positronium formation at Si(111) and Si(001) surfaces has been investigated by changing the doping level systematically over the range 300–1000 K. The temperature dependence of the positronium fraction varied with the doping condition, and there were ...
宮下 敦巳 +19 more
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On the reactions of ortho-positronium and inhibition of positronium formation
, 1976 A study of the interactions of ortho-positronium with a variety of inorganic and organic compounds was undertaken to investigate the mechanisms of the thermal reactions of ortho-positronium and to investigate the processes which inhibit positronium ...
Wild, Ralph Edward
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Principles of positron porosimetry
Nukleonika, 2015 The paper deals with positron porosimetry (PP), which is based on positron annihilation lifetime spectroscopy (PALS). The numerical analysis of positron lifetime spectra for PP is more demanding than in most of other applications of PALS.
Zaleski Radosław
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Prospects for Studies of the Free Fall and Gravitational Quantum States of Antimatter
Advances in High Energy Physics, 2015 Different experiments are ongoing to measure the effect of gravity on cold neutral antimatter atoms such as positronium, muonium, and antihydrogen.
G. Dufour +8 more
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Positronium – Hydrogen Like and Unlike [PDF]
, 2009 On the occasion of the 2008 Brijuni Conference on Hydrogen – the most abundant atomic species in the Universe, it seems fitting to draw attention of the participants of this conference, as well as chemists at large, to Positronium – one of the least ...
Randić, Milan
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