This paper describes an LED-based optically stimulated luminescence (OSL) system for dose profile measurements using OSL detector strips and investigates its performance in x-ray computed tomography (CT) dosimetry. To compensate for the energy response of the Al(2)O(3):C OSL detectors, which have an effective atomic number of 11.28, field-specific energy correction factors were determined using two methods: (a) comparing the OSL profiles with ionization chamber point measurements (0.3 cm(3) ionization chamber) and (b) comparing the OSL profiles integrated over a 100 mm length with 100 mm long pencil ionization chamber measurements. These correction factors were obtained for the CT body and head phantoms, central and peripheral positions and three x-ray tube potential differences (100 kVp, 120 kVp and 140 kVp). The OSL dose profiles corrected by the energy dependence agreed with the ionization chamber point measurements over the entire length of the phantom (300 mm). For 120 kVp x-ray tube potential difference, the CTDI(100) values calculated using the OSL dose profiles corrected for the energy dependence and those obtained from an independent measurement with a 100 mm long pencil ionization chamber also agreed within +/-5%.

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The properties of the yrast states for 100-110 Pd even–even (e–e) nuclei have been established. The relation between the moment of inertia 2ϑ/ℏ2 and the square of the rotational energy (ℏω)2 has been drawn to identify the back-bending that may occur at a certain state for each isotope. The relation between gamma-energy over spin Eγ/I as a function of spin I has been drawn to determine the evolution in each isotope ranging from vibration to rotational properties. The suitable limit in the interacting boson model IBM-1 has been used to calculate the yrast states for each isotope, which are then compared with the experimental results.

Mixed-symmetry assignments are made to the 1.570 (l;), 1.573 (2:) and 1.659 (3:) MeV levels in 2wHg. The characteristics of the 2: level are shared with nearby 2+ levels at 1.254 and 1.593 MeV. An interacting boson approximation (IBA-2) analysis examines the sensitivity of the mixed-symmetry states to the E, parameters of the Majorana term and finds that both the magnitude and sign of the d(E2iM1) mixing ratio of 2' -2: transitions are well reproduced at the values of the tt parameters used to obtain a level energy fit. The IBA-2 calculations also give a satisfactory fit to the energy levels and in general provide X(EOiE2) values close to the experimental data. These calculations agree with the known oblate deformation of the ground state which we find to be predicted by Kumar's dynamic deformation model.Experimental data from n, yy(0) experiments together with internal conversion coefficient (ICC) results allow 1+ levels to be unambiguously established at 1.570, 1.631, 1.718, 2.061, 2.370, 2.640 and 2.979 MeV. The measurements also provide precise 6 values of many transitions while event-by-event coincidence information permits the decay scheme to the developed with previous unlocated transitions now firmly assigned. NUCLEAR REACTIONS '99Hg(n; y)ZWHg; thermal neutrons, measured I,, y-ray coincidences, yy(8); deduced 6(E2/Ml), X(EOIE2), mixed-symmetry states, level scheme; enriched target, Ge(Li) detectors. 3 3 0

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