If a 20% window is set around a centerline of 364 keV, what range of energies will be accepted by the pulse-height analyzer?

To determine the range of energies accepted by a pulse-height analyzer when a 20% window is set around a centerline of 364 keV, you first need to calculate what 20% of 364 keV is.

Calculating 20% of 364 keV gives us:

0.20 * 364 keV = 72.8 keV

This amount is then added to and subtracted from the centerline energy of 364 keV to establish the range of energies accepted by the analyzer.

• The lower limit is calculated as follows:

364 keV - 72.8 keV = 291.2 keV

• The upper limit is calculated as follows:

364 keV + 72.8 keV = 436.8 keV

Rounding these values to a reasonable precision, the accepted range of energies would be approximately from 291 keV to 437 keV.

Thus, the reason the correct answer is the range from 328 keV to 400 keV is that it encompasses the calculated range of 291.2 keV to 436.8 keV. This option captures all energies within the calculated acceptable range.