Contents
People
who contributed to Si3
Summary of Current Status of Production at Purdue
CLEO Si3 Meeting Minutes and Transparencies
Si3 Review Committee Document Draft 2
New: Live Action Video from the CLEO Experimental Hall
CLEO III Silicon Upgrade Photographs and Figures
Various PR plots in postscript
Other CLEO Web Pages
The Cornell CLEO Homepage
Cornell - assorted CLEO pictures (by Chris Bebek)
OSU Silicon group sites
Electronics and Hybrids
OU Silicon Group-Detector Testing and Flex Circuits
Wayne State University - CLEO III Interaction Region and Beam Pipe
Updated: December 17, 1999
The Si3 Group November 30, 1999 with the complete layer 3/4 assembly which contains (about 80% of the silicon). L-R Eric Reber (undergrad), Ian Shipsey (Professor), Steve Kane (undergrad), Kirk Arndt (Engineer), David Miller (Professor), Tom Smith (Technician), Jim Fast (Sr. Scientist), Jik Lee (Research Scientist).
Particle Physics for 7 year olds- Photographs of children who painted the shipping crate. Thank-you notes from the children. Journal & Courier article (which explains how the children came to be involved). Physics for 4 year olds - thank you notes, pictures. Hillcrest Elementary, Delphi, February 12, 2002 thank you notes and photos. Happy Hollow Elementary, West Lafayette, February 27, 2002 thank you notes.
Our latest picture of the silicon detector 11/27/99 is at: CLEO III Silicon Detector Outer Layers (warning this is a high resolution picture).
Pictures of the layer 1 and 2 assembly are at clamshell pictures.
The layer 3 and 4 subassembly journey from West Lafayette to Ithaca.
Why did we build a silicon detector?
The Origin of
Matter:
At the beginning of the Universe all the energy
and matter we see today was squeezed into a space much less
than 1 millimeter across. This confinement produced a very
dense state in which heavy subatomic particles could exist.
When most subatomic particles decay they produce equal
amounts of stable matter and anti-matter, which subsequently
meet and annihilate producing energy in the form of light.
Today's Universe has about
109 times
as much light as matter, and no anti-matter. It is
conjectured that when certain subatomic particles, such as
the beauty quark, decay they do so producing slightly more
matter than anti-matter, so that after annihilation a small
amount of matter remains. Similar processes during the
period
10-35 to
10-12
seconds after the birth of the
Universe may have given rise to the matter that permits us
to exist.
To test this hypothesis the Purdue CLEO
group is part of a 22 university CLEO experiment which
collides electrons with positrons to produce beauty quarks
at the Cornell Electron Storage Ring. As part of an upgrade
to the experiment the Purdue group is leading the
construction of a silicon vertex detector (Si3) which is
based on microelectronic technology similar to a video
camera. Si3 is a very precise, accurate and fast array of
450,000 cameras that detects the birth and death of the
beauty quark, whose existence lasts for a trillionth of a
second. Si3 is the most advanced detector of its type ever
constructed at a university.
Above: The 450,000 cameras, each 50 microns apart, are electrically connected to each other by tiny hair-like wires using a technique called wirebonding. In this picture forty wirebonds are visible. The dime sets the scale. For Si3 half a million wirebonds were made at Purdue.
Much more detail can be found in articles by John Ellis (CERN), Ian Shipsey (Purdue) and the Purdue Univeristy News Service.