Dear experts,
I have recently been studying the use of FLUKA to calculate reaction cross-sections and reaction yields.
While learning on the forum, I came across this discussion Measurement of cross section that mentioned…
sigma[mb] = A[g/mol]/(λ[cm] ∗ ρ[g/cm3] ∗ NA[mol−1]) ∗ 10^27
“ You need to divide the
RESNUCLE resultsbyNumber of stars generated per beam particle: Prompt radiation generated by PROTON, and multiply bysigmawherelambda [cm]is also printed in the output file (Inelastic Scattering Length for PROTON at Beam energy).”
- I don’t understand what
"λ"refers to, and I’m also unclear about" Prompt radiation generated by PROTON."Could you help clarify my confusion?
Additionally, I consulted books and articles.
The books provide a definition of nuclear reaction cross-section:
σ = N / INs [1]
Nis the number of reactions occurring per unit time,
Iis the number of incident particles per unit time,
andNsis the number of target nuclei per unit area.
The articleTransport model predictions of 225Ac production cross sections via energetic p, d and α irradiation of 232Th targets provide a definition of nuclear reaction cross-section:
σ = - ln( 1 − φ_int / φ_o) / nx [2]
Simplify it:
σ = (φ_int) / (φ_o * n * x) [3]
φ_intis the number of product nuclei,
φ_ois the number of incident particles incident on the target,
nis the number of target nuclei per unit volume,
andxis the thickness of the target.
It can be seen that Equation [1] and Equation [3] are equivalent.
（ nx = Nx/V = x[cm] ∗ ρ[g/cm3] ∗ N_A[mol−1] / A[g/mol] )
- Can I consider that…
In the forum:
" RESNUCLE results " is φ_int，
" Prompt radiation generated by PROTON " is φ_o，
" sigma " is 1/nx
Is this understanding correct? If it is correct, why does it say in the forum thatλis"Inelastic Scattering Length for PROTON at Beam energy"? I have checked the .out file. It is stated in the"Material"section that the value ofλis in the teens, which is not the same as the target thicknessx.