CERN experiment improves precision of antiproton mass measurement with new innovative cooling technique
In a paper published today in the journal Science, the ASACUSA experiment at CERN reported new precision measurement of the mass of the antiproton relative to that of the electron. This result is based on spectroscopic measurements with about 2 billion antiprotonic helium atoms cooled to extremely cold temperatures of 1.5 to 1.7 degrees above absolute zero. In antiprotonic helium atoms an antiproton takes the place of one of the electrons that would normally be orbiting the nucleus. Such measurements provide a unique tool for comparing with high precision the mass of an antimatter particle with its matter counterpart. The two should be strictly identical. Read more
The antiproton (p, pronounced p-bar), which is also sometimes referred to as a negatron, is the antiparticle of the proton. The antiproton was experimentally confirmed in 1955 by University of California, Berkeley physicists Emilio Segrč and Owen Chamberlain, for which they were awarded the 1959 Nobel Prize in Physics. Read more