discovery of tau lepton

Discovery of the tau lepton: (Martin L Perl.)

In 1975.

The tau lepton was detected through a series of experiments between 1974 and 1977 by Martin Lewis Perl with his colleagues at the SLAC-LBL group. Their equipment consisted of SLAC's new e+-e− colliding ring, called SPEAR, and the LBL magnetic detector. They could detect and distinguish between leptons, hadrons and photons. They did not detect the tau lepton directly, rather they discovered anomalous events:
There must have been undetected particles because not all energy from the initial collision could be accounted for in the final state. However, they did not detect any other muons or electrons, or any hadrons or photons. It was proposed that this event was the production and subsequent decay of a new particle pair:
This was difficult to verify because the energy to produce the τ+τ− pair is similar to the threshold for D meson production. Work done at DESY-Heidelberg, and with the Direct Electron Counter (DELCO) at SPEAR, subsequently established the mass and spin of the tauon.
Martin Perl shared the 1995 Nobel Prize for physics with Frederick Reines. The latter was awarded his share of the prize for detecting the neutrino.


The Stanford Linear Accelerator Center (SLAC) is a United States Department of Energy National Laboratory operated by Stanford University under the programmatic direction of the U.S. Department of Energy Office of Science. The SLAC research program centers on experimental and theoretical research in elementary particle physics using electron beams and a broad program of research in atomic and solid state physics, chemistry, biology, and medicine using synchrotron radiation.[1] The 3.2 kilometer (2.0 mile) long underground accelerator is the longest linear accelerator in the world, and is claimed to be "the world's straightest object."

pictures.. (in the mirror)

tau decay
stanford linear accelerator centre (where perl did his research)
some part of the discovery of a tau, havent found any actual explanation as yet.
perly

Background of Martin Perl

His parents are from the polish area of Russia and migrated to US in 1900, to escape poverty, they then grew up in the poorer areas of New York. His father was a stationary salesman and his mother a bookkeeper for a firm of wool merchants.

Martin was born in the 1020’s, has a younger sister, lila.

Worked hard in school as his migrant family valued an education and only wanted him to get A’s.
Although He won the physics medal when he graduated from high school.
He was sixteen when he graduated from James Madison High School in Brooklyn in 1942

He never thought of becoming a scientist

his family knew that a man could earn a living as engineer, so he enrolled in the Polytechnic Institute of Brooklyn, now Polytechnic University, and began studying chemical engineering.

joining the United States Merchant Marine, He was allowed to leave college and become an engineering cadet in the program at the Kings Point Merchant Marine Academy.. after this The draft was still in force in the United States. He was drafted, and spent a pleasant year at an army installation in Washington, DC, doing very little. Finally, he returned to the Polytechnic Institute and received a summa cum laude bachelor degree in Chemical Engineering in 1948. Upon graduation, He joined the General Electric Company.
a Chemical Engineer in the Electron Tube Division. He had to learn a little about how electron vacuum tubes worked, so he took a few courses in Union College in Schenectady specifically, atomic physics and advanced calculus. he got to know a wonderful physics professor, Vladimir Rojansky. One day he said to him "Martin, what you are interested in is called physics not chemistry!" At the age of 23, he finally decided to begin the study of physics.
he entered the physics doctoral program in Columbia University in the autumn of 1950. True, he had a summa cum laude bachelor degree, but he had taken only two courses in physics: one year of elementary physics and a half-year of atomic physics. First, graduate study in physics was primitive in 1950, compared to today's standards.
After finishing here, he went on to do his PHD.
He was influenced into particle physics by one of his “teachers” at the university.
received his Ph.D. in 1955. went to michigan.Then went on to discover the tau lepton.

our topic

this is our topic:

MARTIN L. PERL
1995 Nobel Laureate in Physics
for the discovery of the tau lepton.
Background
Born: 1927Residence: U.S.A.Affiliation: Stanford University, Stanford, CA

and Frederick Reines for the detection of the neutrino.

with half each aparently.

hooray

hooray this is a blog.