Towards Antihydrogen Trapping and Spectroscopy at ALPHA

Eoin Butler; Gorm. B. Andresen; Mohammad. D. Ashkezari; Marcelo Baquero-Ruiz; William Bertsche; Paul D. Bowe; Crystal C. Bray; Claudio L. Cesar; Steven Chapman; Michael Charlton; Joel Fajans; Tim Friesen; Makoto C. Fujiwara; David R. Gill; Jeffrey S. Hangst; Walter N. Hardy; Ruyugo S. Hayano; Michael E. Hayden; Andrew J. Humphries; Richard Hydomako; Svante Jonsell; Leonid Kurchaninov; Ricardo Lambo; Niels Madsen; Scott Menary; Paul Nolan; Konstantin Olchanski; Art Olin; Alexander Povilus; Petteri Pusa; Francis Robicheaux; Eli Sarid; Daniel M. Silveira; Chukman So; James W. Storey; Robert I. Thompson; Dirk P. van der Werf; Dean Wilding; Jonathan S. Wurtele; Yasunori Yamazaki

doi:10.1007/s10751-011-0299-3

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arXiv · 1105.0037

Towards Antihydrogen Trapping and Spectroscopy at ALPHA

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Abstract

Spectroscopy of antihydrogen has the potential to yield high-precision tests of the CPT theorem and shed light on the matter-antimatter imbalance in the Universe. The ALPHA antihydrogen trap at CERN's Antiproton Decelerator aims to prepare a sample of antihydrogen atoms confined in an octupole-based Ioffe trap and to measure the frequency of several atomic transitions. We describe our techniques to directly measure the antiproton temperature and a new technique to cool them to below 10 K. We also show how our unique position-sensitive annihilation detector provides us with a highly sensitive method of identifying antiproton annihilations and effectively rejecting the cosmic-ray background.

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Eoin Butler, Gorm. B. Andresen, Mohammad. D. Ashkezari, Marcelo Baquero-Ruiz, William Bertsche, Paul D. Bowe, Crystal C. Bray, Claudio L. Cesar, Steven Chapman, Michael Charlton, Joel Fajans, Tim Friesen, Makoto C. Fujiwara, David R. Gill, Jeffrey S. Hangst, Walter N. Hardy, Ruyugo S. Hayano, Michael E. Hayden, Andrew J. Humphries, Richard Hydomako, Svante Jonsell, Leonid Kurchaninov, Ricardo Lambo, Niels Madsen, Scott Menary, Paul Nolan, Konstantin Olchanski, Art Olin, Alexander Povilus, Petteri Pusa, Francis Robicheaux, Eli Sarid, Daniel M. Silveira, Chukman So, James W. Storey, Robert I. Thompson, Dirk P. van der Werf, Dean Wilding, Jonathan S. Wurtele, Yasunori Yamazaki. 2011-04-30. Towards Antihydrogen Trapping and Spectroscopy at ALPHA. https://doi.org/10.1007/s10751-011-0299-3

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