X- and gamma-rays attenuation properties of DNA nucleobases by using FLUKA simulation code

In this paper, we report on the radiation attenuation properties of the essential DNA nucleobases such as guanine, adenine, cytosine, uracil, and thymine. Gamma attenuation parameters such as linear attenuation factor (LAF) and effective atomic number (EAN) are investigated by using FLUKA simulation code for seven chosen photon energies named 0.6, 1.25, 1.5, 2, 3, 5, and 10 MeV. The validation of the simulation results is performed by using XCOM calculations. Moreover, neutron and charge particles attenuation properties are examined for the essential DNA nucleobases. We also compare the radiation attenuation properties of the essential DNA nucleobases to those of liquid water. Our results indicate that the maximum LAF is observed at 0.6 MeV with the value of 0.183, 0.134, 0.130, 0.110, 0.103, and 0.089 cm−1 for guanine, adenine, cytosine, uracil, thymine, and liquid water, respectively. At a given photon energy, the exposure rate (ER) follows the trend: (ER)liquid water > (ER) thymine > (ER)cytosine > (ER)adenine. At 10 MeV, total stopping power (TSP) of electron interactions with the essential DNA nucleobases are 1.952, 1.977, 1.994, 1.990, 2.013, and 2.149 MeVcm2/g for guanine, adenine, cytosine, uracil, thymine, and liquid water, respectively. Comparatively, TSP of electron