List of equations in nuclear and particle physics

This article summarizes equations in the theory of nuclear physics and particle physics.

(common name/s) N0 = Initial number of atoms at time t = 0 ND = Number of atoms decayed at time t

Q = radiation quality factor (dimensionless) Wj = weighting factors corresponding to radiosensitivities of matter (dimensionless)

hence (approximately)

= − λ

− λ t

The following apply for the nuclear reaction: in the centre of mass frame, where a and b are the initial species about to collide, c is the final species, and R is the resonant state.

σ (

π g

{\displaystyle \sigma (E)={\frac {\pi g}{k^{2}}}{\frac {\Gamma _{ab}\Gamma _{c}}{(E-E_{0})^{2}+\Gamma ^{2}/4}}}

Spin factor:

Total width:

{\displaystyle \Gamma =\Gamma _{ab}+\Gamma _{c}}

Resonance lifetime:

τ = ℏ

d σ

2 μ

sin ⁡ (

{\displaystyle {\frac {d\sigma }{d\Omega }}=\left|{\frac {2\mu }{\hbar ^{2}}}\int _{0}^{\infty }{\frac {\sin(\Delta kr)}{\Delta kr}}V(r)r^{2}dr\right|^{2}}

d σ

csc

sec

ℏ ν

ln ⁡

sin

Scattering potential energy (α = constant):

d σ

csc

These equations need to be refined such that the notation is defined as has been done for the previous sets of equations.