Question

In an accelerator experiment on high-energy collisions of electrons with positrons, a certain event is interpreted as annihilation of an electron-positron pair of total energy 10.2 BeV into two γ-rays of equal energy. What is the wavelength associated with each γ-ray? (1BeV = 10⁹ eV)

Answer 1

Total energy of two γ-rays:

E = 10. 2 BeV

= 10.2 × 10⁹ eV

= 10.2 × 10⁹ × 1.6 × 10⁻¹⁰ J

Hence, the energy of each γ-ray:

Planck’s constant,

Speed of light,

Energy is related to wavelength as:

Therefore, the wavelength associated with each γ-ray is