When using a semiconductor to measure photon energies from a radionuclide, what unit of measurement is shown on the output screen?

When measuring photon energies emitted from a radionuclide using a semiconductor detector, the output is typically displayed in kilo-electron volts (keV). This is because the energies of photons emitted by radionuclides fall within the range of a few keV to several MeV, making the keV a practical and convenient unit for this type of measurement.

Kilo-electron volts are commonly used in nuclear physics and radiation detection because they effectively convey the energy levels relevant to the interactions of photons with matter and are aligned with the energy ranges typically encountered in radionuclide emissions. For context, 1 keV equals 1,000 electron volts, which is a much more manageable value than expressing radiation energy in electron volts alone, especially when dealing with energies that are often in the hundreds or thousands of electron volts.

Other units such as nano-electron volts, microwatts, or joules are not typically utilized in this context. Nano-electron volts would represent extremely low energy levels, which are not encountered with the high-energy photons from radionuclides. Microwatts are a measure of power, which is a different quantity from energy, and joules, while a valid unit of energy, are generally less convenient than keV when discussing the specific energy