Séminaires

Illuminating Antimatter: the ALPHA antihydrogen experiment at CERN

par Dr Jeffrey S. Hangst (Aarhus University)

Europe/Paris
Description
We have recently become able to study atoms of antihydrogen - the antimatter equivalent of hydrogen. The question to be addressed is fundamental and profound: “Do matter and antimatter obey the same laws of physics?” The so-called Standard Model of fundamental particles and interactions requires that hydrogen and antihydrogen have the same spectrum. I will discuss the latest exciting development in antihydrogen physics: observation of a laser-driven transition (1S-2S) in trapped anti hydrogen [1]. Precise measurement of the frequency of this transition could well be described as the ‘holy grail’ of physics with anti-atoms. To study antihydrogen, it must first be produced, then trapped [2], and then held for long enough [3] to observe a transition using very few anti-atoms. I will discuss the techniques necessary to achieve this latest milestone, and then consider the future of optical and microwave [4] spectroscopy, and gravitational studies [5] with antihydrogen. 1.Ahmadi W. et al., Observation of the 1s-2s Transition in Trapped Antihydrogen, Nature doi:10.1038/nature21040 (2016). 2. Andresen, G.B. et al., Trapped Antihydrogen, Nature, 468, 673 (2010). 3. Andresen, G. B. et al. Confinement of antihydrogen for 1,000 seconds. Nature Physics 7, 558 (2011). 4. Amole, C. et al., Resonant quantum transitions in trapped antihydrogen atoms, Nature 483, 439 (2012). 5. Amole, C. et al., Description and first application of a new technique to measure the gravitational mass of antihydrogen, Nature Communications DOI: 10.1038/ncomms2787 (2013).