- #1
Ofinns
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Homework Statement
I have the decay
K+ → μ+ + νμ
Calculate:
1. Momentum of μ+
2. Total energy of νμ
3. Mass of K+
4. Speed of μ+
5. Speed of νμ
Homework Equations
The only thing we get are the kinetic energy of μ+ so Kμ+ = 152.53 MeV
and the mass of mμ+ = 105.658 MeV/c2
The Attempt at a Solution
1. As I only have the kinetic energy for the kaon and mass of the muon I thought that I could use the relation between momentum and kinetic energy: K = p2 / 2m ⇒ p = (2mK)1/2 ≈ 179.53 MeV/c ??
Problem is that the teacher did not provide any anwsers even though these questions are just excercises.
2. The momentum for the neutrino is pνμ2 = Eνμ2 - mνμ2 = Eνμ2 as the neutrino are massless. But the only way I know how to calculate the energy is to know the mass of the kaon. Or to use something similar as in 1. but if so I would need the kinetic energy of the neutrino.
3. The mass of K+ should equal the sum of Eμ+ and Eνμ. But as stated above the only formula I know of how to calculate the energy in a decay like this require the mass of the kaon so yeah.
4. I assume I can use p = γmv where γ = 1 if v << c and if the answer is too close to c I use the relativisic formula instead..?
5. Same, but if this is the case I need to also calculate the momentum of the neutrino.
I know I haven't come very far in my calculations, but as the teacher do not provide any answers it gets even harder. And I have been going through our course material, but there is no example like this so some tips would be great :)Best regards
Isabelle