Detector Probes Beauty and the Big Bang

An outstanding problem ties the realms of the subatomic and the cosmic: The very existence of the universe seems to violate a tenet of the standard model of particle physics -- charge parity reversal. Researchers at Purdue University in West Lafayette, Ind., have created a detector that they hope will enable physicists to understand why the big bang yielded a net imbalance of matter and antimatter.

The instrument, called Si3, is a 21-in.-long cylinder of 450,000 silicon microstrips that have been depleted of free charge carriers. Inserted into the 9- to 12-GeV electron-positron collider at Cornell University's Wilson Synchrotron Laboratory in Ithaca, N.Y., the Si3 will look for charge asymmetry in the decay of beauty quarks.