# How did he calculate the probabilities?

1. Aug 21, 2007

### Urvabara

www.particle.kth.se/SEASA/ph_exjobb.pdf [Broken] (page 24/48)
"The smallest showers detectable with a reasonable probability over a larger area are $$10^{16}$$ eV showers. A lower shower counting rate for the setup can be deduced by only considering showers with this energy. A $$10^{16}$$ eV -shower is detected with a probability of 0.86 at 0 m distance, 0.12 at 100 m, and with zero probability at larger distances. This can be simplified to a probability $$P = \frac{0.86+0.12}{2} = 0.49$$ to detect a shower hitting within 100 m of the center, and zero probability outside this region. This collecting area is then 31415 m$$^{2}$$."

How did he calculate the probabilities 0.86, 0.12 and 0? Please explain, this is so important...

Last edited by a moderator: May 3, 2017
2. Sep 4, 2007

### Urvabara

Never mind...