U. profs win science awards

The Franklin Institute recently announced that Penn professors Robin Hochstrasser and Raymond Davis Jr. are among the winners of the 2003 Benjamin Franklin Medal. These awards, announced Wednesday, are presented annually to leading scientists in a variety of fields. Hochstrasser received the Benjamin Franklin Medal in Chemistry for his development of ultrafast and multidimensional spectroscopies. Davis, a physics and astronomy professor at Penn, was presented with the Benjamin Franklin Medal in Physics for his research in neutrinos and solar fusion reactions -- the same efforts that won him a Nobel Prize in Physics in 2002. Hochstrasser's research used ultrashort laser pulses which make it possible to study very fast processes of molecules and proteins. "The basic question we were trying to answer," according to Hochstrasser, "is how do complex molecules change with time? "We are trying to understand the primary processes of a number of reactions that take place in liquids and proteins," Hochstrasser said. "We developed these methods in order to use them to look at chemical reactions" such as these. When Hochstrasser was notified that he had received the Benjamin Franklin Medal, he was "very excited" and "thought it was just absolutely terrific," he said. But Hochstrasser was quick to point out that "this is a recognition of work that was done by a lot of people, not just by me. This award has been given to me, but it is very much for everybody." Davis' experiment -- which began almost 40 years ago -- involved observing neutrinos and their role in energy reactions, proving that the sun uses the fusion reaction of hydrogen nuclei in energy production. The project began in 1965, when Davis helped design a massive tank at the Brookhaven National Lab, filled with 100,000 gallons of perchloroethylene. By burying the tank thousands of feet underground, Davis and other scientists could monitor the chemical and draw conclusions about the way neutrinos interact. When Davis joined the Penn faculty in 1985, his experiment moved with him into the University's domain. "The technique that Davis used is a very clever one," Physics Professor Kenneth Lande said. "Neutrinos have very small mass, no electric charge and hardly ever interact with matter. Observing them is pretty tough," but Davis' experiment allowed scientists to do just that. Davis' work also brought deeper understanding of neutrinos in general, Lande said. "As neutrinos move from the sun to the earth, they split into three distinct species of neutrinos," he explained. "Neutrinos changing from one species to another is called neutrino flavor transition." This discovery, a direct product of Davis' experiments, opened up a whole new study of neutrinos and their properties. Hochstrasser and Davis will be formally presented with their awards at a reception on April 24.