- #1

- 157

- 1

## Homework Statement

Hi everybody, I was studyng a photon disintegrating in one electron and one positron in the presence of a heavy atomic core; I want to find the final momentum of the atomic core

## Homework Equations

Conservation of energy: Eγ=2me+Sqrt(Mn

^{2}+Pn

^{2})

Conservation of momentum Pγ=Pn

Relation between the energy and momentum of a maseless particle Pγ=Eγ

## The Attempt at a Solution

From the conservation of energy: (Eγ-2me)

^{2}=Mn

^{2}+Pn

^{2}; and since Pn=Eγ, operating after developing

**(Eγ-2me)**

Can anyone please tell me what am I doing wrong?

Thanks.[/B]

^{2}, I obtain Pn=4me-(Mn^{2}/me). If I introduce the values in units of atomic mass, I obtain a negative value of Pn, the momentum of the atomic core.Can anyone please tell me what am I doing wrong?

Thanks.