At the upcoming Joint Meeting of the American Physical Society (APS) and the American Association of Physics Teachers (AAPT) in Columbus, Ohio, the following news conference will take place in room B205 at the Columbus Convention Center.

The newsroom itself will be room B204, where the phone numbers are 614-722-1202 and -1203; the fax number is 614-722-1204. In addition, a general news release on the meeting as well as several lay language papers exists at our "Virtual Pressroom" website: www.aps.org/BAPSAPR98/vpr/.

NEWS CONFERENCE: A Dense Nuclear Environment Affects Particle Decays. Saturday, April 18, 9:30 AM. An electron moves more slowly in a silicon-based semiconductor than it does in a gallium-arsenide semiconductor, even when subjected to the same forces. Physicists therefore say that an electron has a higher "effective mass" in silicon than it does in gallium arsenide. Similarly, particles produced inside a hot, dense collision between heavy nuclei can have altered effective masses because of their environment. Presenting experimental evidence of how these particles, such as quark-antiquark pairs, decay into their final products, Johann Peter Wurm of the Max Planck Institute in Germany ( [email protected]) and Volker Koch of LBL (510-486-5323) will discuss how the altered effective masses of these particles influence their lifetimes and decay paths. Spencer Klein, Lawrence Berkeley Laboratory.