International Conference on Precision Physics of Simple Atomic Systems

Session

Session 7

19 May 2026, 14:00

Festsaal (ÖAW)

21. Updates on the 1S-2S spectroscopy of antihydrogen at the ALPHA experiment at CERN

Claudio Lenz Cesar (Federal University of Rio de Janeiro (BR))

19/05/2026, 14:00

Talk

We discuss, on behalf of the ALPHA collaboration, studies of some systematic effects on the 1S-2S spectroscopy on trapped and laser-cooled antihydrogen atoms through the use of a quasi-analytical lineshape [1]. This work is part of the preparation of a manuscript soon to be submitted by the ALPHA collaboration that should significantly improve the measurement of this transition frequency over...

54. Energy-Selective Annihilation of Trapped Antihydrogen via Positron Spin Flips

Abbygale Grace Swadling (University of Calgary (CA))

19/05/2026, 14:30

Talk

The imbalance of observed antimatter in the Universe remains an open problem in modern physics. Simple anti-atomic systems provide unique platforms to test the fundamental symmetries that predict equal amounts of matter and antimatter. Antihydrogen is an attractive candidate owing to its simple composition and the extensive study of its matter counterpart. The ALPHA (Antihydrogen Laser PHysics...

80. The ASACUSA antihydrogen beam

Ross Edward Sheldon (Austrian Academy of Sciences (AT))

19/05/2026, 14:50

Talk

Comparisons of hydrogen to antihydrogen provide an excellent test of CPT symmetry, particularly in identifying any symmetry breaking between matter and antimatter. The energy levels of atomic hydrogen are some of the most precisely characterised quantities in nature, the challenge therefore lies in measuring the properties of antihydrogen to the same level of precision to make a meaningful...

86. Measurements of charge exchange cross sections of antiprotons with positronium in GBAR: Towards synthesis of antihydrogen ions

Ivana Belosevic (Université Paris-Saclay (FR))

19/05/2026, 15:20

Talk

The origin of matter-antimatter asymmetry is one of the big unanswered questions in modern physics. Various experiments look for an explanation of this asymmetry by searching for CPT symmetry violations and by testing the Weak Equivalence Principle with antimatter. The GBAR (Gravitational Behaviour of Antihydrogen at Rest) experiment at CERN seeks to measure the gravitational acceleration of...