Antihydrogen atom formation in a CUSP trap towards spin polarized beams

N. Kuroda, Y. Enomoto, K. Michishio, C. H. Kim, H. Higaki, Y. Nagata, Y. Kanai, H. A. Torii, M. Corradini, M. Leali, E. Lodi-Rizzini, L. Venturelli, N. Zurlo, K. Fujii, M. Ohtsuka, K. Tanaka, H. Imao, Y. Nagashima, Y. Matsuda, B. JuhászE. Widmann, A. Mohri, Y. Yamazaki

Research output: Contribution to journalArticle


The ASACUSA collaboration has been making a path to realize high precision microwave spectroscopy of ground-state hyperfine transitions of antihydrogen atom in flight for stringent test of the CPT symmetry. For this purpose, an efficient extraction of a spin polarized antihydrogen beam is essential. In 2010, we have succeeded in synthesizing our first cold antihydrogen atoms employing a CUSP trap. The CUSP trap confines antiprotons and positrons simultaneously with its axially symmetric magnetic field to form antihydrogen atoms. It is expected that antihydrogen atoms in the low-field-seeking states are preferentially focused along the cusp magnetic field axis whereas those in the high-field-seeking states are defocused, resulting in the formation of a spin-polarized antihydrogen beam.

Original languageEnglish
Pages (from-to)31-40
Number of pages10
JournalHyperfine Interactions
Issue number1-3
Publication statusPublished - 2012 Dec 1



  • Antihydrogen
  • Atomic beam
  • CPT invariance
  • Rydberg atom

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Nuclear and High Energy Physics
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry

Cite this

Kuroda, N., Enomoto, Y., Michishio, K., Kim, C. H., Higaki, H., Nagata, Y., Kanai, Y., Torii, H. A., Corradini, M., Leali, M., Lodi-Rizzini, E., Venturelli, L., Zurlo, N., Fujii, K., Ohtsuka, M., Tanaka, K., Imao, H., Nagashima, Y., Matsuda, Y., ... Yamazaki, Y. (2012). Antihydrogen atom formation in a CUSP trap towards spin polarized beams. Hyperfine Interactions, 212(1-3), 31-40.