Laser Cooling of Antihydrogen

Antihydrogen, the simplest atomic antimatter system, is an excellent platform to search for matter- antimatter asymmetries. The kinetic energy (and thus velocity) of synthesized antihydrogen trapped in the laboratory setting is very large relative to the energy well depth of the trap providing the confining force. Accuracy of any measurements performed on trapped antihydrogen, and the complexity of future experiments, is sensitive to the kinetic energy of the sample. There are a variety of techniques used in atomic physics experiments to decrease a sample’s temperature, but the additional constraints of working with trapped antimatter made laser cooling the most promising choice. I demonstrate the ability to modify the kinetic energy distribution of a trapped sample of antihydrogen using the 1S-2Pf transition in antihydrogen using a vacuum ultraviolet (VUV) laser system (i.e. laser cooling). The change in kinetic energy is observed using a time-of-flight analysis from a pulsed laser spectroscopy run as well as a narrowing of the 1S-2S line shape. Using the centre frequencies of the 1S- 2S and 1S-2P transitions we can also determine a value for the Lamb shift in antihydrogen. I will detail these results as well as my individual contributions toward this achievement of the ALPHA collaboration. In this thesis I observed an increase in both the 1S-2S, 1S-2P, and time of flight when the laser cooling transition was applied, when compared to control and laser heating runs. Using the trap depth of the neutral atom trap confining the antihydrogen sample, I estimate the temperature of the laser cooled sample to be approximately 31mK, an order of magnitude decrease. This will be demonstrated through changes in transition linewidths, both the 1S-2P and 1S-2S transition, as well as increases in time-of- flight data.

Name thesis:degree_name

Doctor of Philosophy (PhD)

Discipline thesis:degree_discipline

Physics & Astronomy

Grantor dc:publisher.institution

Science

Year dc:date.issued

2022

Author dc:creator

• Evans, Andrew

Advisor dc:contributor.advisor

• Thompson, Robert

Committee members dc:contributor.committeemember

• Jackel, Brian
• Ouyed, Rachid
• Moazzen-Ahmadi, Nasser
• Lassen, Jens

• Antimatter
• Antihydrogen
• Laser Cooling

Statement dc:rights

• University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.

Language dc:language.iso

eng

DOI

http://dx.doi.org/10.11575/PRISM/39502

OAI identifier oai:identifier

oai:ucalgary.scholaris.ca:1880/114287