Download presentation
Presentation is loading. Please wait.
Published byGeorgia Hunter Modified over 9 years ago
1
My Life as a Guest Scientist at Fermilab Tim Brennan, Academic Year 2000-2001
2
Outline I. The Fermilab Site II. The BTeV Experiment a. Big Picture b. Little Picture (my experimental work) III. The Impact on Classroom(s) a. New Lessons in “Old” Courses b. New Courses? c. Virtual Lab
17
The BTeV Experiment Goals: - use Tevatron to create more B quarks/mesons than ever - use the statistics to test the validity of the Standard Model - specifically look for CP violation (a “preference” for matter) Techniques - build a new detector facility, a la CDF and D0 - use low-cost computing techniques, in bulk, for fast decisions - use new technologies to precisely recreate particle tracks Time Frame - be ready by 2005
19
My Role on the BTeV Team The BTeV team asked me to design some electronics for a photomultiplier tube, a device used to measure the energy of photons (and particles that produce photons) that are created during the collision of protons with anti-protons. Photomultiplier Tube (PMT) Basics: - a series of metallic plates held at increasing voltages - first plate (photocathode) receives light through a window - electrons are liberated via the photoelectric effect - next stage receives the electrons (e-) from the first stage - each e- is capable of releasing 3-4 more e- at the next stage - multiple stages results in lots (millions) of e- - output of last stage (anode) needs to be counted
20
Base Electronics Requirements - establish and maintain the high voltages needed for each stage - take up as little room as possible - dissipate as little heat as possible - produce an appropriate output signal that can be integrated - output should be a linear function of input Number of e - = K * (Energy of Input light) where K is a constant
22
A Typical Result of the Base Electronics Performance
23
Input Light (digitized ‘counts’) Output Charge (digitized ‘counts’) Each count =.25 pC. 1000 counts = 250 pC. Response of six-stage base and tube to light of various energies
24
Input Light (digitized ‘counts’) Output Charge (digitized ‘counts’) Each count =.25 pC. 1000 counts = 250 pC. Response of ten-stage base and tube to light of various energies
25
Input Light (digitized ‘counts’) Output Charge (digitized ‘counts’) Each count =.25 pC. 1000 counts = 250 pC. Space-Charge Effect? Notice the “roll-off.”
26
Impact on Classroom(s?) New Lessons in Old Courses - particle interactions - electromagnetics - data analysis - astrophysical phenomena - fruits from a world-class technical library - “hardware” (articles) - “software” (greater understanding via reading) New Courses?? - interdisciplinary course encompassing statistics, science, and computer technology OR - AP Statistics course?
27
The Photoelectric Effect Virtual Lab - demonstrates principles of photoelectric effect - low cost (free!) option for doing High Energy Physics lab - web-based technology - student-centered, constructivist application - graphical interpretation of critical physics principle - students induce mathematical rule first induced by Einstein - students can explain why light must be considered a particle - provides students a hands-on introduction to quantum world
32
Many Thanks for a Special Year: - Fermilab Education Office: Tom, Liz, Marge, Spencer, Melissa, Lamargo, and Nancy, for ideas, support, and laughs - Fermilab’s Visual and Media Services, for tech help - BTeV experimenters, for taking me on as a Fellow - Fermilab Library Staff, Celina and Rob, for research and ideas - Woodstock HS School Board, for granting this sabbatical - Teaching Colleagues, for keeping me connected - Russell and Ward, our unofficial guides to Chicago - my families and friends, for their love and support - and to Beth, who, in the course of this past year, left TWO jobs that she loved so that I might pursue this amazing opportunity, and without whom I never would have dreamed it, pursued it, or lived through it. I am blessed to share my life with her. Thank You! Thanks to all who made this a remarkable year!
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.