hep in the classroom dr. sascha schmeling cern/ep hst programme 2001
TRANSCRIPT
HEP in the Classroom
Dr. Sascha SchmelingCERN/EP
HST Programme 2001
Overview Particle Physics as a Subject in Schools
Example for a curriculum Popular School Experiments
CRT, e/m, Millikan Self-built Experiments
Cosmic muon detection Short Discussion
available experiments existing knowledge
Hands-on Workshop
Curriculum
1. Repetition of known experiments Cathode Ray Tube, Millikan, e/m
2. Work with an interactive system3. Discuss found problems,
Work on specific topics Homework: Preparation of Short Talks
4. Talks, Q&A5. “Own” experiment, Outlook,
Links to other subjects
if not, it isa good
opportunity!!!
many systemsalready available
Feynman diagrams, various experiments
Cloud Chamber mostly known for
nuclear physics experiments
principle see the name
possible experiments visualisation of
elementary particles
Rutherford’s Experiment THE experiment to
show that matter on our scales has a substructure
principle scattering
241Am
primary beam
gold foil
scattered beams
detector
Cathode Ray Tube well-known
experiment, with screen useable for various effects
principle acceleration with
electrical fields deflection with
different field types
cath
od
e
ano
de
acce
lera
tio
n v
olt
age
vacu
um
tu
be
elec
tro
n b
eam
Electron Beam Diffraction Tube
not really particle physics but good possibility to show the wave nature of electrons
principle Bragg reflection at graphite electron waves
possible experiments: wave length measurement h measurement
Millikan Experiment classical experiment
(first performed 1916) to show quantisation of the electrical charge
principle: electric force
possible experiment: measurement of
electron charge
There exist manyready-to-use appletseven from teachers
for teachers!
Multimedia Tools
Some of these experiments cannot be shown in every school, as they are expensive.
Why not use multimedia for this?
Example: Millikan-Experiment with ViMPS
Pupils always use computers!
Black box!
Anyway, one should restrict
that!Sure, but there is the need – sometimes!
Fine Beam Tube
instructive measurement of electron properties
principle: Lorentz Force
possible experiment: measurement of
e/m
Theoretical input:
e/m Experiment Measurement:
r
vmFcenter
2
2
,
2
.2
21
Uevm
UeEvmE accelelectrickin
veBFLorentz
22
2
rB
U
m
e
e/m ?
r
electron beamcathode
accel. voltage
magneticfield
Circular Accelerator
Franck-Hertz Experiment also not a real
“particle physics” experiment but good to show quantisation
principle: ionisation by electrons
possible experiment: illustrate Bohr’s model
Self-Made Experiments In contrast to these – expensive – standard
experiments, it is possible to set up small experiments with available or not expensive to buy pieces, such as
coffee pots neon tubes wire
with these tools it is possible to perform nice experiments with cosmic muons
KamioCan
Muon detection
small spark chamber
KamioCan small experiment to
detect muons
simple set-up power supply oscilloscope photomultiplier pot
with large(r) pot you can measure the muon lifetime
PC needed documented electronics
Muon Lifetime expected signal
from photomultiplier
background (non-) - +background +
for unfolding one could fit a function and derive the muon lifetime:
t
etf
)(
Nice to relate to mathematics!?
only usefor t>~2s
Neon Tubes another small
experiment to detect cosmic muons
very simple set-up neon tubes (even faulty
ones) power supply
adjustable to your needs/wishes
granularity efficiency
TheEnd
Questions?!
See youat the
workshop!