G. Satyanarayana

Lα/Ll X-ray intensity ratios for elements in the region 55≤Z≤80

L alpha /Ll X-ray intensity ratios are measured in 19 elements in the region 55<or=Z<or=80. A 30 mCi 238Pu source is used to provide the excitation while a high-resolution Si(Li) detector connected to a 4 kbyte multichannel analyser and a microprocessor is used for the detection and measurement of X-ray intensities. The results show agreement with the theoretical predictions of Scofield (1969).

Kβ/Kα x-ray intensity ratios

Abstract The K β /K α X-ray intensity ratios in the elements Bi, Th and U were measured using a high resolution hyper pure germanium detector system. These results were combined with the values for Z between 20 and 82 as reported by the present authors and fitted to a polynomial. The fitted values are found to be in satisfactory agreement with the experimental values as well as with those due to Scofield. The most probable values of K β /K α are interpolated from the fit for several elements in the region of Z between 83 and 92.

K-electron capture probability in 167Tm

The K-electron capture probability in the decay of 167Tm for the first-forbidden transition 1/2+ to 3/2- was measured using the sum-coincidence method and employing a hyper-pure Ge system. The PK value is found to be 0.835+or-0.029, in agreement with the theoretical value of 0.829.

Gamma transitions and their relative intensities in153Eu

SummaryA careful search for the weak transitions in153Eu nucleus is made following the electron capture decay of153Gd with a high-resolution Si(Li) detector system. Two new transitions with energies 14.07 and 19.8 keV are observed. The energies and relative intensities of different gamma-rays are computed and given.RiassuntoUn’accurata ricerca delle transizioni deboli nel nucleo di153Eu si attua seguendo il decadimento di cattura dell’elettrone di153Gd con un sistema di rivelatore Si(Li) ad alta risoluzione. Si osservano due nuove transizioni con energie di 14.07 e 19.8 keV. Si calcolano e si forniscono le energie e le intensità relative dei diversi raggi gamma.РеэюмеИсследуются слабые переходы в ядрах153Eu и прослеживается злектронный распад153Gd, испольэуя детектор высокого раэрещения Si(Li). Обнаружены два новых перехода с знергиями 14.07 и 19.8 кзВ. Вычисляются знергии и относительные интенсивности раэличных гамма-лучей.

Kβ/Kα X-ray intensity ratios in elements with 20 ⩽ Z ⩽ 50

Abstract An accurate measurement of the Kβ/Kα ratios of X-ray intensities in elements with Z lying between 20 and 50 is undertaken using X-ray and radioactive source excitation methods. A high resolution Si(Li) detector spectrometer is used for the intensity measurements. The results show that the experimental values of Kβ/Kα for elements with Z above 40 are not consistent with the theoretical predictions due to Scofield. The experimental values are fitted to a polynomial and the Kβ/Kα values of elements not studied are interpolated using the polynomial fit.

Anomalous Conversion Coefficient of the 150.6 keV (11/2-→5/2+)Transition in 111mCd

The total conversion coefficient of the 150.6 keV (E3) transition in the decay of 11/2 - state ( T 1/2 =48.6 minutes) in 111m Cd is determined employing a high resolution HpGe detector system and the intensity balance method. The experimentally measured α T is found to be 1.76±0.08 and deviate from the theoretical value of Hager and Seltzer by (23±3)%. The E3 hindrance with respect to the single particle estimate is determined to be 8.5×10 3 . The results are discussed.

Measurement of conversion coefficients of M3 transition in 60mCo and M4 transition in 90mY

The K-conversion coefficient of 58.6 keV (2+ to 5+) M3 gamma transition in 60mCo and the total conversion coefficient of 479.53 keV (7+ to 3-) M4 gamma transition in 90mY were measured by X-ray, gamma -ray and intensity balance methods, respectively, using high-resolution solid-state detectors. The values obtained were alpha K=39.04+or-1.90 in 60mCo and alpha T=0.0990+or-0.0013 in 90mY. These results are seen to be consistent with the theoretical values due to Rosel and co-workers (1978).

Measurement on K-electron capture probabilities in the decay of 183Re and 168Tm

The K-electron capture probabilities for the 5/2+ to 3/2- transition in the electron capture decay of 183Re to the 208.805 keV level in the daughter 183W and for the 3(+) to 3- and 3(+) to 4/sup /transitions in the electron capture decay of 168Tm to the 1541.4 keV and 1093.9 keV levels, respectively, in the daughter 168Er were measured for the first time using an X- gamma summing method. The experimental PK values are reported in this paper, together with those due to theory, and discussed.

Measurement of K-electron capture probability in the decay of 87Y

The K-electron capture probability for the 1/2- to 3/2- transition in the decay of 87Y to the 873.0 keV level in the daughter 87Sr was measured for the first time using an x- gamma summing method. The experimental Pk value was found to be 0.911+or-0.047, in agreement with the theoretical value of 0.878.

A study of (Lβ2,15+Lβ5+Lβ6)/(Lα1+Lα2) ratio in 5d-shell elements and their compounds

Abstract We have studied the dependence of (L β2,15 +L β5 +L β6 )/(L α1 +L α2 ) ratio on the chemical constitution of the X-ray emitting atom in Hf, Ta, W and Hg of 5d-shell elements through a selective excitation of the L III subshell. The results show that the variation in this ratio is up to 25% when compared with those of pure elements.