Makoto Fujiwara,
TRIUMF Research Scientist,
ALPHA-Canada Spokesperson

As the spokesperson of the Canadian group on the ALPHA project at CERN, I am writing to highlight the contributions made by Prof. Hardy's UBC group in our recent achievement on trapping of antihydrogen, a result which just appeared on Nature on November 17, 2010.

The UBC team, led by Prof. Walter N. Hardy, and includes a Ph.D. student, Andrea Gutierrez, and a former M.Sc. student, Sarah Self El Nasr, has made very important contributions to this international project at CERN. We also had a couple of excellent undergraduate co-op students working with us over the past years: Winnie Lai, Lee Wasilenko. (Incidentally, I might note that myself and Prof. Michael Hayden of SFU, are UBC Physics alumni).

Prof. Hardy has been invited to participate in this international project due to his world-leading expertise in low temperature physics and precision microwave spectroscopy. In particular, he is the then world record holder of stability of cryogenic atomic hydrogen maser, in research he conducted in 1980s at UBC, together with his then student Michael Hayden, who is now an SFU professor.

Since the beginning of the ALPHA project in 2005, Prof. Hardy's group has made several decisive contributions, not only in the area of his expertise in low temperature physics, but also in particle detector physics and plasma physics, the areas outside of his expertise. ALPHA is an interdisciplinary research project, where researchers from different fields work together, but cross-disciplinary impact of Prof. Hardy has been widely recognized as exceptional. I give you just a few examples:

• Together with his former student, Sarah Seif El Nasr, and in collaboration with TRIUMF, Prof. Hardy constructed a novel particle detector system to detect antimatter annihilations. The original detector we had built at TRIUMF had several problems. Using his expertise in low temperature physics and electronics, Prof. Hardy has hand-machined a prototype for a greatly improved version of detector, at Physics Student Machine shop on one weekend. The new design by Prof. Hardy proved to be much superior, and Prof. Hardy and his students, with help of TRIUMF, later produced more than dozen modules. This system was crucial in the early stage of ALPHA, and has resulted in several important publications.
• He has also made several notable contributions in the area of plasma physics. Shortly after he joined the ALPHA collaboration, and he quickly learned a new subject (for him) of trapped plasma physics, he soon after came up with a very unconventional idea for cooling trapped particles. This was initially received with strong scepticism by the experts, but he was able to persuade them in the end. More recently, he has devised a new experimental technique in diagnosing the condition of plasmas using radio-frequency signals. This has proven to be very powerful, and will likely constitute a major part of a Ph.D. thesis for a Canadian student at Univ. of Calgary, with whom Prof. Hardy works closely. Most recently, Prof. Hardy came up with a totally new idea for measuring temperatures of trapped plasmas. Temperature measurements are major research topic in plasma physics, and his new approach is showing excellent promises, with the potential of major impact in the field. I stress again that these contributions are in the areas outside of Prof. Hardy's expertise.
• He has also made a number of technical contributions, both for the construction of the apparatus at home and he operation of the experiment at CERN. This includes the design and the construction of, low heat conducting high voltage cable system, mechanical mounting system for scintillation detector system, various improvements for cryogenic and vacuum systems based on his rich laboratory experiences. Throughout these efforts, Prof. Hardy has been working closely students and postdocs in ALPHA, both Canadians and non-Canadians, who are benefitting tremendously by gaining hands-on experiences, working side-by-side with Prof. Hardy.
• I would also like to stress that Prof. Hardy exhibits work ethics exemplary to younger students as well as to his colleagues. He puts in tremendous long hours while at CERN, and his attention to the details, constant new ideas, and enthusiasm for science, are extremely valuable assets to our collaboration.

Currently, as we speak, Prof. Hardy, together with Prof. Hayden of SFU, is leading a very ambitious effort for microwave spectroscopy of antihydrogen atoms at CERN. This is the original reason he was invited to join ALPHA. And precision spectroscopic studies of antimatter atoms, to see if there is any difference with matter atoms, is the reason why we wanted to trap antihydrogen in the first place. So we are entering a very exciting time in ALPHA, and Prof. Hardy's expertise will be absolutely central to the effort of this international project.

I hope that this memo will give you a flavour of the tremendous contributions of Prof. Hardy's group has made in the past and will likely to make in the future. If you have any questions, please do not hesitate to contact me (Makoto.Fujiwara@triumf.ca), or Prof. Jeffrey Hangst (Jeffrey.Hangst@cern.ch ), the spokesperson of ALPHA.