1. PHYS264-Scattering and Transport
Tuesday 2. February 2010
Topic:
Differential Cross sections – Classical particle scattering
Comment:
Preliminary version without text, sent by
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2. differential cross sections
FROM PREVIOUS LECTURES
Probability for single scattering – or collision – or deflection – or simply event
Now towards the
differential cross sections
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3. differential cross section
Typical definition of
differential cross section
We use instead analogy with sport-shooting (air-gun) or darts-game s
D P
D s =
Target – D P – probability for a given event 10,9,5,3 ...
D s is the area
Of the given «number» s
D P
D s =
What is s ? The area of the target – or e.g. the square enclosing it?
It is the area of possible beam/target encounter
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4. As we can see, there is always a COLLISION PLANE.
This is given by the two parallel lines:
1. The velocity of the «projectile» through the original position PLANE
2. The line parallel to 1. but passing through the scattering centre SCATTERING
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5. Such scattering can be realized by simple mechanical models – provided we manage to mostly eliminate friction
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6. Attractive potential
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7. Repulsive potential
(just changed sign)
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8. slide from
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9. PHYS264 spring page 9

10. As we can see, there is always a COLLISION PLANE.
This is given by the two parallel lines:
1. The velocity of the «projectile» through the original position PLANE
2. The line parallel to 1. but passing through the scattering centre SCATTERING
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11. slide from
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12. slide from
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13. slide from
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14.
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15. slide from
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16. slide from Topic_1_2008_exam NEXT TIME
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17. Possible improvements of the «board technology» ? ? ?
I will try using my own program in JavaScript inside Sea-Monkey
The above has been written using my own program
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