What is the maximum wavelength photon that can produce a pair of tau particles (mass 1.777 GeV/c²) by pair production? A) 8.72 × 10⁻⁸ nm B) 3.49 × 10⁻⁷ nm C) 6.98 × 10⁻⁷ nm D) 1.74 × 10⁻⁷ nm

Question

Quizplus · Accepted Answer

The energy threshold for producing a pair of tau particles is given by $E_{th} = 2m_{	au}c^2 = 3.554$ GeV. The energy of a photon is given by $E = hc/\lambda$. Therefore, the maximum wavelength photon that can produce a pair of tau particles is given by $\lambda_{max} = hc/E_{th} \approx 3.49 	imes 10^{-7}$ nm, which corresponds to choice B.

What Is the Maximum Wavelength Photon That Can Produce a Pair