Download “Subatomic Physics” explores the phenomena which take place at

Subatomic Physics
“Subatomic Physics” explores the phenomena which take place at
subatomic distances scales.
Practically, subatomic physics is divided into two research areas:
• Nuclear Physics
• Particle Physics
The particle and nuclear topics will be covered by different
lecturers - both of whom is also an active researcher in that field.
•
Dr Dan Watts - Nuclear Physics
•
Dr Victoria Martin - Particle Physics
•
[email protected]
•
[email protected] JCMB 5419
JCMB 8209
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Lectures, Tutorials & Notes
• Lectures are Tuesday & Friday at 10am in JCMB C
• Tutorials are on Wednesdays, 11am-12noon & 12noon-1pm in JCMB 5212,
starting week 3.
• No tutorials weeks 6 and 12 (to avoid clash with Research Methods in
Physics).
• Tutorials will be attended by the lecturer plus 1 or 2 assistants.
sheets will be circulated in advance of the tutorials.
Questions
• The tutorials will give you an opportunity to work on the problems, ask for
help and advice on the problems and lectures.
• Notes for the lectures, problem sheets etc will be linked from:
www2.ph.ed.ac.uk/~vjm/Lectures/SubatomicPhysics/Subatomic2010.html
www2.ph.ed.ac.uk/~dwatts1/sa_09.htm
We’ll link to the School of Physics & Astronomy wiki too!
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From the Atom to Subatomic
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nucleus
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quarks &
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Nuclear
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Particle
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Subatomic Forces
• At subatomic scales interactions between particles and nuclei are
caused by the three subatomic forces:
• The electromagnetic force
• The weak nuclear force
• The strong nuclear force
• The course will focus on phenomena occurring at subatomic scales, as
opposed the mathematical framework describing the forces.
• The interactions due to these forces are evident in:
• Scattering: e.g. scattering of protons on protons at the LHC
• Particle Decay: e.g. decay of radioactive nuclei, decays of cosmic-ray
muons
• Nuclear Fission and Fusion, e.g.: reactions in a nuclear reactor
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→
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56 Ba
89
+36
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Why Separate Nuclear and Particle?
• Particle and Nuclear physics look, broadly, at the same underlying physics, but a
different energy/length scales.
➡ Although the underlying physics is the same, different phenomena exhibited at
these different scales.
• Electromagnetic force stops me from putting my hand through the table.
➡ Using quantum description of electromagnetic force between each electron is
much too complex!
➡ Instead use van der Waals interaction to describe electromagnetic potential
between atoms
• Similarly, nuclear fission is due to interplay of strong and electro-magnetic forces in
nuclei.
➡ A particle physicist would consider strong and electroweak force between each
quark in the nuclei!
➡ Ingenious nuclear physicists describe fission much more simply…
•
Particle & Nuclear Physics probe scales just different enough to require
different descriptions to obtain a good understanding of the phenomena.
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