High detection efficiency

SIMS has superb surface sensitivity since most of the secondary ions originate within a few nanometers of the surface and since high detection efficiency enables as little as 10 " of a monolayer to be detected for most elements. Because of its very high surface sensitivity, SIMS can be used to obtain depth profiles with exceptionally high depth resolution (<5 nm). Since the beam of primary ions can be focused to a small spot, SIMS can be used to characterize the surface of a sample with lateral resolution that is on the order of micrometers. Elements with low atomic numbers, such as H and He, can be detected, isotope analysis can be conducted, and images showing the distribution of chemical species across... 

The instrument MIMOS 11 is extremely miniaturized compared to standard laboratory Mossbauer spectrometers and is optimized for low power consumption and high detection efficiency (see Sect. 3.3) and [326, 327, 336-339]. All components were selected to withstand high acceleration forces and shocks, temperature variations over the Martian diurnal cycle, and cosmic ray irradiation. Mossbauer measurements can be done during day and night covering the whole diurnal temperature... 

High detection efficiency (detection of single ions)... 

Lenne, P. F. Etienne, E. Rigneault, H., Subwavelength patterns and high detection efficiency in fluorescence correlation spectroscopy using photonic structures, Appl. Phys. Lett. 2002, 80, 4106 4108... 

Gamma Rays (Nuclear-decay y-Rays, 0.5-m.e.v. Photons from Annihilation of Positrons or X-rays). The development of large sodium iodide crystal 7-ray spectrometers (13) has made possible high detection efficiencies (close to 100% for some 7-ray energies). Also, whole-body counters utilizing large cylindrical liquid scintillators provide a detection efficiency of 15% for the 7-rays emitted from potassium-40 in the human body (23). 

Si(Li) crystals provide high detection efficiency between 1.5kev and 30kV, but at higher energies the low photon absorption efficiency of Si results in background levels comparable to peak... 

The detector is a Siemens Ar-Me proportional flow counter which has high detection efficiency for Cu radiation. 

ToF systems are well suited to the pulsed nature of SIMS and MALDI measurements, and combine many characteristics that are advantageous to imaging experiments. High detection efficiency, parallel detection, and a wide m/z detection range have made them ubiquitous for MALDI and SIMS-MSI. Recent improvements in measurement speed have particularly benefited MSI experiments. Modem commercially available MALDI-ToF instruments are equipped with solid-state lasers that allow acquisitions at up to 2 kHz. Such speed is a prerequisite for the development of higher spatial resolution analysis and three-dimensional imaging or for the analysis of large animal/ patient series of tissues. 

Ion tr experiments can achieve high detection efficiency of the ion s internal states. Unit detection efficiency has been achieved in previous experiments on quantum jumps [13] where the internal state of the ion is indicated by light... 

Linear analyzers and conventional TLC scanners are standard equipment in nuclear medicine. These instruments offer high detection efficiency and resolution characteristics combined with speed of analysis, which is required for the analysis of short-lived radiopharmaceuticals. 

The very high detection efficiency of this apparatus, which normally exceeds 50% as directly determined from the coincidence counting statistics, invites attempts to detect other particles in coincidence in order to learn more... 

McCarroU and Thomson have described the use of a solid-state windowless device for the direct monitoring of surfaces under UHV conditions. The detection system had excellent vacuum properties, a high detection efficiency for [14-C] 3 particles, and good background characteristics. However, since the detector was light sensitive, the apparatus had to be operated in total darkness. 

The combined low background, high detection efficiency, and 5.5-ml sample volume lead to a detection limit of 10 Bq (600 dpm) per liter for a 100-min count (95% confidence limit). These results are achieved routinely in field tests of the FDTAS at monitoring wells, surface streams, ground water remediation facilities, sewage treatment plants, and the Savannah River. Results have been confirmed by parallel sampling and laboratory analyses. 

The detection efficiency of silicon is low above 20 keV. A higher-Z, pixellated, detector is therefore included behind the silicon CCD. The silicon is therefore thinned down to the active thickness to minimise unwanted absorption. Due to the depth of focus of the optics, the second detector may be up to 15 mm beJiind the silicon CCD. In order to determine changes in source continua above 20 keV and to resolve cyclotron lines, we require to combine high detection efficiency with an energy resolution of between 1-2 keV over the energy band 20-60 keV. We envisage the use of a hybrid array of diodes constructed on... 

The resolution of a wavelength-dispersive spectrometer is not required, so that the high detection efficiency of a proportional counter, an NaI(Tl) detector, or a Si(Li) detector can be utilized. 

Laboratory measuring equipment used in radiochemical analytical procedures should show a high radiation sensitivity, high detection efficiency, low background, and high stability. 

In this case, it can be seen that the two-parameter calculations predicted quite a high detection efficiency, and yet the most likely value of v was reduced significantly, indicating that a determination of v is rather sensitive to the missing of even a small fraction of the weak levels. 

High detection efficiency is particularly needed in nuclear microprobes, where the beam intensity is limited furthermore, beam current density has to be kept below a certain level, depending on the sample material, to avoid irradiation damage. For example, for a 1 pm beam spot and 100 pA beam current the determination of Li, B, and is possible in... 

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