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In the pres ent work we in ves ti gated the gamma ra di a tion pa ram e ters as mass at ten u a tion coef fi cients m/r, the to tal atomic scat ter ing cross-sec tions s t , the elec tronic scat ter ing cross-sections s e , the ef fec tive atomic num bers Z eff , and the ef fec tive elec tron den si ties N eff for some poly mers such as polyoxymethylene (CH 2 O), poly acrylonitrile (C 3 H 3 N), nat u ral rub ber (C 5 H 8), poly ethyl acrylate (C 5 H 8 O 2), polyphenyl methacrylate (C 10 H 10 O 2), and poly eth ylene tetraphthalate (C 10 H 8 O 4). The gamma ray pho tons were de tected by NaI(Tl) de tec tor with res o lu tion of 8.2 % at 662 keV, us ing ra dio ac tive gamma ray sources 57 Co, 133 Ba, 137 Cs, 54 Mn, 60 Co, and 22 Na at en er gies 122, 356, 511, 662, 840, 1170, 1275, and 1330 keV. Val ues of m/r for the cho sen poly mers de crease with in creas ing en ergy. The re sults of in ves ti gated data are use ful in plas tic in dus try, build ing ma te ri als, ag ri cul ture fields ra di a tion shield ing, ac cel er a tor cen ters, poly mer in dus try, med i cal field, etc.

In pres ent work we use NaI(Tl) de tec tor in nar row-beam good ge om e try setup for the gamma ray at ten u a tion stud ies of some low-Z ma te ri als. The pa ram e ters such as mass at ten ua tion co ef fi cients, ef fec tive atomic num bers and ef fec tive elec tron den si ties, atomic cross-sections, elec tronic cross-sec tions of ma te ri als for gra phitic pow der, polycarbonate, poly vi nyl chlo ride, plas ter of Paris, gyp sum, and lime stone were de ter mined us ing gamma ray sources 57 Co, 133 Ba, 137 Bs, 60 Co, and 22 Na at en er gies of 122, 356, 511, 662, 840, 1170, 1275, and 1330 keV. It was ob served that the ef fec tive atomic num bers and ef fec tive elec tron den si ties ini tially de crease and tend to be al most con stant as a func tion of gamma-ray en ergy. An attempt was done to check the avail abil ity of these low-Z ma te ri als at large scales and ob tain able at low cost as gamma ray shield ing ma te ri als. The in ves ti gated data are use ful in elec tronic indus try, plas tic in dus try, build ing ma te ri als, and ag ri cul ture fields.

In the present work half value layer (HVL), tenth value layer (TVL)and mean free path (Mfp) are the most frequently used important parameter for explaining both the penetrating ability of particular radiations and the penetration through specific objects or material. The half value layers (HVL), tenth value layers (TVL) gives the thickness of a shield or an absorber that reduces the radiation level by a factor of one-half and one tenth of the initial level, respectively. The concepts of HVL and TVL are widely used in shielding design. In the present investigation we calculated the values of linear attenuation coefficient, mean free path (MfP), half value layer (HVL) and tenth value layer (TVL) for some oxides such as aluminum oxide, manganese oxide, copper oxide and magnesium oxide in the energy range from 122keV to 1330keV were measured. The transmitted intensity of photons emitted by radioactive isotopes of 133Ba, 22Na, 137Cs, 54Mn and 60Co measured using the NaI(Tl) scintillation detector and results obtained are in good agreement with the values reported in the present study.