Photon energy per

Number particles, energy per particle, Mev Number Gamma photons, energy per photon, Mev... 

In the earlier Q system, was calculated by using the mean photon energy per disintegration taken from ICRP Publication 38 [1.11]. Furthermore, the conversion to effective dose per unit exposure free-in-air was approximated as 6.7 m Sv/R from photon energies between 50 keV and 5 MeV. 

Finally, mention should be made of the tfeatment of positton annihilation radiation and conversion electrons in the determination of Q values. The latter are treated as monoenergetic beta particles, and weighted according to their yields. In the case of annihilation radiation this has not been included in the evaluation of the beta dose to the skin since it contributes only an additional few per cent to the local dose to the basal layer. However, the 0.51 MeV gamma rays are included in the photon energy per disintegration used in the derivation of as discussed above. 

Calculate the linear momentum per photon, energy per photon, and the energy per mole of photons for radiation of wavelength... 

Instead of molecule, moles (1 mol = 6.022 x 10 molecules Avogadro number) are often used in experimental chemistry. The unit of photon energy referenced to one mole is called an einstein. Photon energy per 1 einstein of light with wavelength X (nm) is expressed as... 

Table 2.3 Photon energy per mole for UV-visible light of typical wavelengths...

What is the energy per photon of the sodium D line ( i = 589 nm) SOLUTION... 

Figure 6 RHEED (upper) end reflection enisotropy (iower) trensients obtained by interrupting and resuming As flux during otherwise normai growth (001) GaAs at 1 semiconductor ML per 4.6 s. Data are shown for photon energies near the Ga RD peak at 2.5 eV (right) and minimum at 3.5 eV (ieft).

A carbon dioxide laser produces radiation of wavelength 106 micrometers (1 micrometer = 10-6 meter). If the laser produces about one joule of energy per pulse, how many photons are produced per pulse ... 

Self-Test 1.5A Another discharge lamp produces 5.0 J of energy per second in the blue region of the spectrum. How many photons of blue (470 nm) light would the lamp generate if it were left on for 8.5 s ... 

Self-Test 1.5B In 1.0 s, a lamp that produces 25 J of energy per second in a certain region of the spectrum emits 5.5 X 1019 photons of light in that region. What is the wavelength of the emitted light ... 

So, 2.1 x 10 5 nm radiation, by virtue of possessing the smallest wavelength in the set, has the greatest energy per photon. Conversely, since 4.1 x 103 nm has the largest wavelength, it possesses the least amount of energy per photon. 

Whereas the amount of energy per UV photon is fixed, the amount of energy per type of photon can vary enormously. 

A dim light emits fewer photons than does a bright light. So a dimmer switch is merely a device for varying the flux of photons emitted by a light bulb. The energy per photon is not significantly altered in this way. 

So, in summary, the extent of the damage caused by these different types of UV light depend on the amount of energy per photon of light, itself a function of its wavelength. 

In Worked Example 9.3, we calculated that each photon has an energy of 1.99 x 10-15 J. To convert from the energy per particle to the energy per mole, we multiply the answer by the Avogadro number, L = 6.022 x 1023 mol-1 ... 

---