Colloquium: Positronium physics and biomedical applications

SD Bass, S Mariazzi, P Moskal, E Stępień - Reviews of Modern Physics, 2023‏ - APS
Positronium is the simplest bound state, built of an electron and a positron. Studies of
positronium in vacuum and its decays in medium tell us about quantum electrodynamics …

Bound-state relativistic quantum electrodynamics: A perspective for precision physics with atoms and molecules

Á Nonn, Á Margócsy, E Mátyus - Journal of Chemical Theory and …, 2024‏ - ACS Publications
Precision physics aims to use atoms and molecules to test and develop the fundamental
theory of matter, possibly beyond the Standard Model. Most of the atomic and molecular …

Discrete symmetries tested at 10−4 precision using linear polarization of photons from positronium annihilations

P Moskal, E Czerwiński, J Raj, SD Bass… - Nature …, 2024‏ - nature.com
Discrete symmetries play an important role in particle physics with violation of CP connected
to the matter-antimatter imbalance in the Universe. We report the most precise test of P, T …

Positronium Laser Cooling via the Transition with a Broadband Laser Pulse

LT Glöggler, N Gusakova, B Rienäcker, A Camper… - Physical Review Letters, 2024‏ - APS
We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly
saturating the 1 3 S-2 3 P transition with a broadband, long-pulsed 243 nm alexandrite laser …

Single-photon large-momentum-transfer atom interferometry scheme for Sr or Yb atoms with application to determining the fine-structure constant

JS Schelfhout, TM Hird, KM Hughes, CJ Foot - Physical Review A, 2024‏ - APS
The leading experimental determinations of the fine-structure constant α currently rely on
atomic photon-recoil measurements from Ramsey-Bordé atom interferometry with large …

Two-body -state energies at order

V Patkóš, VA Yerokhin, K Pachucki - Physical Review A, 2024‏ - APS
We present an analytical calculation of the complete α 6 correction to energies of n P levels
of two-body systems consisting of the spin-0 or-1/2 extended-size particles with arbitrary …

Precision Microwave Spectroscopy of the Positronium Interval

RE Sheldon, TJ Babij, SH Reeder, SD Hogan… - Physical Review Letters, 2023‏ - APS
We report the results of a new measurement of the positronium 2 S 3 1→ 2 P 3 2 (ν 2)
interval. Using a modified experimental arrangement we have significantly reduced the …

Cooling positronium to ultralow velocities with a chirped laser pulse train

K Shu, Y Tajima, R Uozumi, N Miyamoto, S Shiraishi… - Nature, 2024‏ - nature.com
When laser radiation is skilfully applied, atoms and molecules can be cooled,–, allowing the
precise measurements and control of quantum systems. This is essential for the fundamental …

QED corrections to the correlated relativistic energy: One-photon processes

Á Margócsy, E Mátyus - The Journal of Chemical Physics, 2024‏ - pubs.aip.org
This work is a collection of initial calculations and formal considerations within the Salpeter–
Sucher exact equal-time relativistic quantum electrodynamics framework. The calculations …

[HTML][HTML] Photoproduction of QED bound states in future electron-ion colliders

R Francener, VP Gonçalves, BD Moreira, KA Santos - Physics Letters B, 2024‏ - Elsevier
In this work we perform an exploratory study of the photoproduction of singlet QED bound
states (l− l+) S in electron-ion collisions at the EicC, EIC and LHeC energies. The total cross …