E-CodeNeutron moderation: xi and collisions — a TI-84 Plus CE program
SLOWDOWN is a TI-BASIC program for the TI-84 Plus CE. Average logarithmic energy loss per collision for any moderator mass number, collisions needed to thermalise, moderating power and moderating ratio.
What it asks for and what it shows
It asks for 5 values at its prompts. In the example below it shows ALPHA, XI, COLLIS, MOD PWR, MOD RAT.
Example run
One of its oracle test cases: “graphite”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Input 1 | 12 |
| Input 2 | 2000000 |
| Input 3 | 0.025 |
| Input 4 | 0.385 |
| Input 5 | 0.0003 |
| The screen shows | |
ALPHA= | 0.7159763314 |
XI= | 0.1577689898 |
COLLIS= | 115.3429277 |
MOD PWR= | 0.06074106108 |
MOD RAT= | 202.4702036 |
How it's checked
5 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 31 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-84 Plus CE calculator and pick “Neutron moderation: xi and collisions” (SLOWDOWN).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
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- Reactor decay heat after shutdown
All TI-84 Plus CE engineering programs · All TI-84 Plus CE programs