Upping the anti

日期:2019-02-27 10:19:09 作者:葛埘 阅读:

THE US is stealing the limelight back from Europe in the race to harvest antiatoms. Physicists at Fermilab, near Chicago, announced last week that they created seven atoms of antihydrogen in November. The researchers fired a jet of hydrogen gas across a beam of antiprotons. When antiprotons shoot past hydrogen nuclei they can create electron-positron pairs. Occasionally, a positron combines with an antiproton to make antihydrogen. Antihydrogen first appeared at CERN, the European Centre for Particle Physics near Geneva (This Week, 6 January, p 4). CERN made a total of nine antihydrogen atoms. Glenn Blandford, a physicist at the University of California, Irvine, who is working at Fermilab,