The sample	A direct optical band gap (E ), eV g	Indirect optical band gap (E ), eV g
Pure Cr-39	3.91	3.56
4 MRad	4.09	3.51
6 MRad	3.68	3.44
8 MRad	3.46	3.41
10 MRad	3.34	3.38

Table 1: The optical band gap (Eg) values of pure and irradiated Cr-39

Table 1

Scheme 1

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Scheme 1 The chemical structure of the Cr-39

Figure 1: The X-ray diffraction spectra of pure Cr-39 and Cr-39 irradiated with 4, 6, 8, and 10 MRad

Figure 2: The FT-IR spectra of CR-39 before and after being irradiated with different gamma-ray doses

Figures 3 UV/Vis. absorbance spectra of the studied CR-39 before and after being irradiated with different gamma-ray doses

Figures 4: UV/Vis. transmittance spectra of the studied CR-39 before and after being irradiated with different gamma-ray doses

Figure 5:Absorption coefficient versus photon energy of the studied CR-39 before and after being irradiated with different gamma-ray doses

Figure 6: The relations between (αE_ph)^1/2 as a function of E_ph

Figures 7: The relations between (αE_ph)² as a function of E_ph

Figures 8:the plot between the extinction coefficients (k) versus wavelength (λ) of the samples