الفهرس 
Use of ??Mn (n, ?)?? Mn reaction in standard neutron dosimetry
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Abstract
In this thesis, a prototype Manganese bath was designed and constructed. It is composed of three parts; the 1st part is a spherical 304 stainless steel vessel with a diameter of 34 cm.The 2nd part is a hydraulic system composed of a pump for circulating the manganese (⁵⁵Mn) sulphate solution between the bath and the detection system and filter from stainless steel to prevent impurities.The 3rd part is a detection system composed of a Marinelli beaker with a 1-liter volume attached to a 3”x3” Sodium Iodide doping with Thallium (NaI (TI)) crystal detector protected in a lead shield with its electronic system.A californium (²⁵²Cf) neutron source with a flux of order 103 (n. cm⁻². s⁻¹) was used. The output dose was measured by a calibrated neutron monitor.The output flux was calculated from the flux-dose relationship. It was found that the flux delivered by the used²⁵²Cf was 170.56 ± 6.41 n. cm2. s-1 as calculated from dose measured by the neutron monitor NM2. The photopeak efficiency (f) for 56Mn atom was measured by using standard Marinelli which contains different isotopes then calculated by analytical method from linear fitting. It was found that the photopeak efficiency for 56Mn atom was 2.85 x 10⁻³ ± 1.2 x 10⁻⁴. Different concentrations of ⁵⁵Mn solution were prepared with the molarity of 0.89,1.18 and 1.48 mol/l.252Cf source was supported in the center of the bath for 24 h for each concentration.The calculated fluxes were 194.48, 186.46, and 169.79 n.cm⁻². s⁻¹ for concentration 0.89, 1.18 and 1.48 mol/l respectively. The calculated flux was improved by increasing the concentration.The uncertainty for the measured fluxes is 8.32, 7.1 and 6.67 % for concentrations 0.89,1.18 and 1.48 mol/l respectively.The uncertainty value improved with the concentration increased.The obtained data of neutron fluxes for the concentrations 1.18 and 1.48 mol/l was in good agreement with the flux measured by the calibrated neutron monitor and the certificated value of the used source