Neutrino-nucleon quasi-elastic CC scattering

This gives: ν + n → ℓ⁻ + p; ν̄ + p → ℓ⁺ + n

• Charged current, threshold ~E_ν > m_ℓ
• Dominant CC channel for MeV–GeV neutrinos
• Major in supernovae, solar (νₑ), reactors, accelerator beams

Neutrino-nucleon deep inelastic scattering (ν + N → ℓ + X)

• CC and NC, requires E_ν ≳ few GeV
• Dominant at high energies (atmospheric, accelerator, astrophysical)
• Very high rates in high-energy astrophysical environments