Advances in germanium detector technology

Critical comparison of radiometric and mass spectrometric methods for the determination of radionuclides in environmental, biological and nuclear waste samples

“…It is therefore, more Ge(Li) detectors were replaced by HpGe detector in many radioanalytical laboratories, although the performance of both detectors are similar. The recent development in the γ-spectrometry is the introduction of large-volume Ge crystal, which significantly increases the counting efficiency to 100%-150% (relative counting efficiency) [14], this is very useful for the analysis of environmental and waste samples.…”

“…Table 4 lists radionuclides typically measured by beta counting and their approximate detection limits. The GM counter cannot be used effectively for the determination of radionuclides emitting low energy electrons, such as 3 H, 14 C, 129 I, and 241 Pu, because of high absorption of these β-particles in the detector window, LSC has to be used in this case. Besides the capability of being able to measurement low energy β -emitters, LSC also has the advantage of none or minimal selfabsorption, high counting efficiency, homogeneous distribution of the sample in the scintillation cocktail, relative simple sample preparation procedure, and easy standardization using internal or external standard.…”

“…AMS emerged in the late 1970s from nuclear physics laboratories and soon became used as an ultra-sensitive mass spectrometric technique for measuring isotopes of elements, and is now widely used for the determination of radionuclides, especially long-lived radionuclides, such as 3 H, 10 Be, 14 C, 26 Al, 32 Si, 36 Cl, 41 Ca, 53 Mn, 59 Ni, 129 I, 182 Hf, 210 Pb and actinides [31,71,72]. Almost all AMS facilities can be understood as two mass spectrometers (called "injector" and "analyzer") linked with a tandem accelerator.…”

“…Carbon-14 is a naturally occurring radionuclide produced in the upper atmosphere by reaction of cosmic ray produced neutrons via 14 N (n, p) 14 C, 14 C level in the atmosphere was approximately constant before the human nuclear activity (equilibrium between new generated 14 C and removal of 14 C due to its radioactive decay). After being fixed in living materials (plants, animals), the 14 C concentration will decreased due to its radioactive decay with a half life of 5730 y, 14 C is therefore widely used for dating (age determination) purpose.…”

“…There are many radionuclides naturally occurring in the environment, including the isotopes of uranium and thorium and their decay products, 40 K, and those produced from the cosmic ray reactions, such as 3 H, 7 Be, 10 Be, 14 C, 26 Al, 14 C, and 129 I. The interest in the determination of these radionuclides mainly comes from the application of them in geochronology ( 14 C, 10 Be, 210 Pb, etc.…”