DZero's Gaston Gutierrez receives Edward A. Bouchet Award

Students of Gaston Gutierrez never forget him.

Two of his former students, Florencia Canelli and Juan Estrada, still apply the lessons that they learned from their mentor several years ago on the DZero experiment. “Juan and I worked very closely with Gaston. Even now, when faced with a difficult problem, we try to imagine how Gaston would solve it,” said Canelli, now a physicist with a joint appointment between Fermilab and the University of Chicago.

As a result of his contributions to the DZero experiment and his dedication to mentoring young scientists like Estrada and Canelli, Gutierrez received the 2009 Edward A. Bouchet Award from the American Physical Society.

“Gaston is a multi-talented scientist and certainly deserving of this award,” said Darien Wood, a DZero spokesperson. “He has a hands-on approach with both hardware and analysis and doesn’t cut any corners.”

When Gutierrez joined the DZero collaboration in 1997, his first project was to build the central fiber tracker, one of four major parts at the heart of the detector. When he wasn’t constructing the tracker, he developed a new analysis technique, called the matrix-element method, to measure the mass of the top quark.

“I like to work on both construction and analysis,” Gutierrez said. “Ideally you build it, and then you use it. Unfortunately the cycle between the two has been getting longer.”

In this case, the long cycle allowed Gutierrez to perfect his matrix-element method. Before Gutierrez developed the new technique, physicists would compare their data to simulations, limiting the amount of information received. The matrix-element method uses all knowledge about the theory, which, in its first use, focused on the top quark. “You need to have a very well understood detector to use this technique,” said Estrada, who worked with Gutierrez as both a graduate student and a postdoc on DZero. “It used all the work we had done to that point on the top quark. Now it is becoming a standard analysis technique for both DZero and CDF.”

Canelli and Estrada were both graduate students at the University of Rochester when they started working with Gutierrez. With their home institution 650 miles away, Gutierrez took them under his wing and collaborated with their advisor, Tom Ferbel. “I encouraged my students to work with Gaston,” said Ferbel, who nominated Gutierrez for the award. “Florencia and Juan both have strong careers now. A lot of that was triggered by their work with Gaston.”

Both Canelli and Estrada have won numerous awards for their research on the mass of the top quark, attesting to the positive impact that Gutierrez had on their developing careers. “Working with Gaston is the best thing that ever happened to me,” said Estrada. “I’m not a student any more, but I still like to work with him because I know that everything will come out perfectly.”

-- Elizabeth Clements