Martin
Lewis Perl (June 24, 1927 – September 30, 2014) was an American chemical engineer and physicist who won the Nobel Prize in Physics in
1995 for his discovery of
the tau lepton. Perl was born in New York City, New York.
His parents, Fay (née Resenthal), a secretary and bookkeeper, and
Oscar Perl, a stationery salesman who founded a printing and advertising
company, were Jewish immigrants to the US from the Polish area
of Russia. Perl
is a 1948 chemical engineering graduate
of Brooklyn Polytechnic Institute (now known as NYU-Tandon) in Brooklyn. After graduation, Perl worked for
the General Electric Company,
as a chemical engineer in a factory producing electron vacuum tubes. To learn
about how the electron tubes worked, Perl signed up for courses in atomic
physics and advanced calculus at Union College in Schenectady, New York,
which led to his growing interest in physics, and eventually to becoming a
graduate student in physics in 1950. He
received his Ph.D. from Columbia University in
1955, where his thesis advisor was I.I. Rabi. Perl's thesis described measurements of the nuclear
quadrupole moment of sodium, using the atomic beam resonance
method that Rabi had won the Nobel Prize in Physics for in 1944. Following
his Ph.D., Perl spent 8 years at the University of Michigan,
where he worked on the physics of strong interactions,
using bubble chambers and spark chambers to study the scattering of pions and
later neutrons on protons. While at Michigan, Perl and Lawrence W. Jones served as co-advisors to Samuel C. C. Ting, who earned the Nobel Prize in Physics in
1976. Seeking a simpler interaction mechanism to study, Perl started to
consider electron and muon interactions. He had the opportunity to start planning
experimental work in this area when he moved in 1963 to the Stanford Linear Accelerator
Center (SLAC), then being built in California. He was particularly interested in understanding
the muon: why it should interact almost exactly like the electron
but be 206.8 times heavier, and why it should decay through the route that it
does. Perl chose to look for answers to these questions in experiments on
high-energy charged leptons. In addition, he considered the
possibility of finding a third generation of
lepton through electron-positron collisions. Perl is one of
the 20 American recipients of the Nobel Prize in Physics to sign a letter addressed
to President George W. Bush in May
2008, urging him to "reverse the damage done to basic science research in
the Fiscal Year 2008 Omnibus Appropriations Bill" by requesting additional
emergency funding for the Department of Energy's Office of Science, the National Science Foundation,
and the National
Institute of Standards and Technology. He
died after a heart attack at Stanford University Hospital on September
30, 2014 at the age of 87. The tau lepton (τ, also called the tau particle, tauon or
simply tau) is an elementary particle similar
to the electron, with negative electric charge and a spin of 1⁄2, but with 3477 times the mass. Together with
the electron, the muon, and the three neutrinos, it is classified as a lepton.