Detector energy resolution

The 48Ca + 244Pu experiment was repeated in June-October, 1999. During a period of 3.5 months, two more a-decay sequences, terminating in spontaneous fission, were observed [48]. The two chains were identical within the statistical fluctuations and detector-energy resolution, but differed from the first chain measured in 1998. The two new events were assigned to the decay of 288114, the 4n evaporation channel. The cross section was 0.5 pb. 

Figure 12.41 Si(Li) detector energy resolution as a function of X-ray energy (from Ref. 2). What is indicated as electronic noise is the width P,.

Figure 3.1 Spectra from thick anode x-ray tubes, (a) The energy spectrum from a molybdenum anode x-ray tube measured with a Si(Li) detector (40 kV tube voltage, 39-/Lim-thick beryllium x-ray tube window, 90° electron beam incidence angle, 32° x-ray takeoff angle). Although the low spectral intensity near 40 keV makes accurate measurement of Emax difficult, the spectrum approaches zero intensity near 40 keV. The Mo K lines occur at 17.4 keV and 19.8 keV, and the L lines are visible at 2.4 keV. (b) The spectrum from (a) transformed into the wavelength coordinate system. The Mo L line at 5.3 A is broad due to the Si(Li) detector energy resolution. The value of Xmin is readily apparent at 0.31 A. (c) The spectrum from (a) on a linear vertical scale, (d) Spectra from tungsten, molybdenum, and chromium anode x-ray tubes. The positions of characteristic lines are marked by vertical lines of arbitrary height. (Adapted from R. Tertian, Fluorence X, Theorie et Pratique de VAnalyse, Thesis, Universite de Paris, and reprinted by courtesy ofEG G ORTEC.)...

Surface-barrier and diffused p-n junction detectors are the best detectors available for low-energy and heavy-charged particles. Typical detector energy resolutions are in the order of 10-20 keV with 100% detector efficiency. Practical limitations in the construction of these detectors restrict the depletion depths to less than 2 mm. The cost of these detectors is low. 

This S/N ratio obviously depends on the detector energy resolution, the setting of the single channel analyser and on the radiation source spectrum. It is this last point that concern us. 

Detector Energy Resolution Colli- mator CPS Integral CPS Iodine Window CPS Bkgd Iodine Bkgd... 

The temperature dependence of the light yield is a second important factor which could affect in a significant way its performance as a scintillation detector, in particular it directly affects the detector energy resolution. The Lanthanum Halide materials have an uncommon temperature stability in a veiy large temperature range which make them suitable to use also in very harsh or hostile environment. 

The ability to identify different mass species depends on the energy resolution of the detector which is typically 15 keV fiill width at half maximum (FWFIM). For example, silver has a mass M2 = 108 and tin has a mass A , = 119. The difference between . = 0.862 and = 0.874 is 0.012. For 2 MeV helium ions the... 

W. K. Chu, J. W. Mayer, and M. -A. Nicolet. Backscattering Spectrometry. Academic Press, New York, 1978, brief section on nuclear reaction analysis, discussions on energy loss of ions in materials, energy resolution, surface barrier detectors, and accelerators also applicable to NRA ... 

The depth resolution of ERDA is mainly determined by the energy resolution of the detector system, the scattering geometry, and the type of projectiles and recoils. The depth resolution also depends on the depth analyzed, because of energy straggling and multiple scattering. The relative importance of different contributions to the depth resolution were studied for some specific ERDA arrangements [3.161, 3.163]. 

The energy resolution of an X-ray detector is experimentally defined by the full width at half maximum (FWHM) of the Mn-Ka line. The FWHM, in eV, can also be calculated by use of the relationship ... 

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