# Which force mediates a reaction in which a pion and a deuteron form two protons?

## Which fundamental interaction is responsible?

Poll closed Jun 22, 2011.

2 vote(s)
66.7%

1 vote(s)
33.3%
3. ### Electromagnetic

0 vote(s)
0.0%
1. Jun 15, 2011

### alby

Which fundamental force mediates the reaction $\pi^+ + D \rightarrow p + p$?

My initial assumption was the strong force because states only feature quarks (i.e. there are no leptons) but looking at it again I'm not 100% sure.

Do I need to include colour factors? Could it be a neutral current Z without lepton pair production? Or electromagnetic, photon absorbed by proton?

2. Jun 15, 2011

### alphali

am sure that the strong interaction mediates the reaction in which a pion and a deuteron form two protons.and yes u should include a color factor.the deuteron is made of a proton and neutron.the positive pion interacts with the neutron and leads to the formation of a proton .is a simple way a positve pion is made of up and anti down,and the neutron is made of ddu.so the down and anti down annihilate which leaves uud which is a proton.
u can also read this paper made specifically for pre-university level to understand the pion exchange mechanism which include color charge and gluones.http://teachers.web.cern.ch/teachers/archiv/HST2002/feynman/Pion%20exchange.pdf" [Broken]

Last edited by a moderator: May 5, 2017