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Bubble Chamber Relativity

Teachers Calculations

	p_x (GeV/c)	p_y	p_z
K^-	8.26131	-0.15642	0.01320
p	0	0	0
p^-	4.49326	0.73621	-0,01320
p	0.32496	-0.45360	-0.04282

For these calculations we will use the relativistic energy-relation

E² = p² c² + m² c⁴ = (p_x² + p_y² + p_z²) c² + m² c⁴ (1)

where p is the momentum of the particle and m is the mass.

Energy before the interaction:

The incoming particle K^- plus the proton, initially at rest:

We put the data we have got for K^- and the proton into the equation (1) (do the inputs by yourself):

E_before = E_K + E_p = [(p_x² + p_y² + p_z²)_kC² + m_k²c⁴ ]^1/2 + m_p c² = 9.2158 GeV

In the same way we use the data we have got for the proton and p^- particles after the interaction.

E_after = E_p + E_p = [p_p² c² + m_p ² c⁴]^1/2 + [p_p² c² + m_p ² c⁴]^1/2

= 4.58390 GeV + 1.09251 GeV = 5.67641 GeV

Then, according to energy conservation we have a missing energy of (9.2158 – 5.67641) GeV = 3.53939 GeV. So what about that?

Last modified: 25 July 2001