Fundamental Tests with Antihydrogen Atoms
Motivated by the baryogenesis problem (the scarcity of antimatter in the University), CERN's ALPHA collaboration has been studying the properties of antihydrogen atoms. Since first trapping antiatoms in 2010, we have learned to routinely trap over 1000 antiatoms simultaneously, and keep the antiatoms trapped for many tens of thousands of seconds. We have been able to measure the 1S-2S and hyperfine bandwidths to the 10kHz level, which, by some metrics, is competitive with the best CPT tests. In addition, we have measured the Lyman-alpha line as a precursor to laser cooling the antiatoms, and measured the antiatom charge to 0.7ppb. We are constructing a new apparatus designed to measure the antimatter g to 1%; this will be a test of the weak equivalence principle. This talk will describe how we trap antihydrogen, and discuss our physics results.