Gamma rays associated with the decay of states in 102Ag nucleus have been identified, sixty-four of them for the first time following the reaction 50Cr (56Fe, 3pn) 102Ag at a mean energy of 195 MeV. Identification was made using an array of nine, escapesuppressed Ge detectors coupled to a Daresbury Recoil Separator. Excited states in 102Ag were identified using recoil-gamma and gamma-gamma coincidences. From the intensity balance and the coincidence data, a new set of levels was identified which may be interpreted as the reminiscent of "three quasiparticle" bands in neighboring odd-mass nuclei and similar to a four quasi-particle band observed in 106Ag.

Background: During the analysis of certain natural radionuclides in plant samples using gamma spectroscopy, the presence of 40K in the sample causes the overlap of its Compton region with the full energy peaks of 238U, 232Th, and their daughter. Therefore, it is necessary to remove potassium before the measurement to enhance analytical accuracy. Materials and Methods: Five different plant samples were used to validate the method. For each sample, the analysis was performed using two separation methods (original and K-separation), and both were measured with the gamma detector. Comparison of the results achieved using the two methods with regard to spectrum, peak-to-total ratio, obtained activity, and minimum detectable activity (MDA) indicated that the proposed method yielded improved results. Results: The separation procedure removed most of potassium present in the samples. The peak-to-total of energy peaks < 1000 keV increased significantly. The spectrum after K-separation exhibited a lower continuum under the peaks, and the shapes of the peaks were more identifiable. Comparison of MDA values derived before and after the application of K-separation showed an improvement in analytical accuracy. Conclusion: The removal of potassium from plant samples is effective in decreasing the MDA of the spectroscopy by reducing the Compton continuum of the 40K isotope under the energy peaks of interest. Therefore, the application of this method can augment the measurement possibilities for samples with low radioactivity.

Background: A few elements of soil are radioactive. Soil can transfer radionuclide into plants feeding human. Sometimes their levels are as high as to be concern of human healthy. Rice has an important share for Iranian foods especially in north of Iran. Therefore we decided to obtain radionuclides concentration emitting g rays in Lahijan City (Northern Iran) rice fields using g spectroscopy.Methods: Twenty eight samples from rice field's soils and 12 samples from superficial soils were collected at a square of 10*10 m2 to get 2kg weight. To make dry samples were put into oven at 105oC for 24h. Then they were milled and 950 gr of each sample was transferred to Marinelli container with 1000cc volume, sealed and left for 40 days to get secular equilibrium. After measuring Ph, Electric conductivity and organic carbon, g spectroscopy was done to get sample gamma spectrum at 2000-6000 sec using HpGe detector.Results: It was found 226Ra activity in rice fields of 29.273±0.72 Bqkg-1 and city soil of 31.02±1.1 Bqkg-1 and also 232Th activity of 37.47±1.12 Bqkg-1 for rice fields’ soils and 40.47±1.68 Bqkg-1 for city soil were in standard mode.Conclusion: 40K activities mean value according to UNSCEAR; 2000 was found a little greater than standard. A little value of 137Cs was found in Lahijan rice fields and city soils that could be as a result of Chernobyl accident. In except of 137Cs, for three other under studied city soil elements, activities were greater than that of rice fields.