Coincidences source strength

From this relation it follows that a good, i.e., large, ratio of true to accidental coincidences requires a small coincidence resolving time At and a small source strength (f J<7). However, for small values of N all counting rates, Ix, l2, and /true, are small, and therefore the ratio r is not well suited as a criterion of the quality or feasibility of coincidence experiments. Indeed, a more appropriate figure of merit follows if the relative error a of true coincidences, defined by... 

Figure 4.49 The normalized collection time TcM norm. of equ. (4.115) as a function of the relative source strength N(r)/N(r = 1), and for <5 = 0. The parameter r is the ratio of true-to-accidental coincidences, and r-1 = N(r)/N(r = 1). The parameter <5 describes the error attached to the measured number of accidental coincidences (see equ. (4.112)). The collection time decreases for increasing source strength for practical applications the asymptotic limit is reached well enough for foJ(r)/M(r = 1) = 10. From [Kra94] see [VSa83].

If separate blast sources are located close to one another, they may be initiated almost simultaneously. Coincidence of their blasts in the far field cannot be raled out, and their respective blasts should be superposed. The safe and most conservative approach to this issue is to assume a maximum initial blast strength of 10 and to sum the combustion energy from each source in question. Further definition of this important issue, for instance the determination of a minimum distance between potential blast sources so that their individual blasts may be considered separately, is a factor in present research. 

While absorption of CCM is enhanced in the presence of a light meal, it can also be consumed on an empty stomach and still be sufficiently absorbed (Heaney et al, 1989b Higdon, 2005). The same cannot be said for some other Ca salts and Ca supplements in tablet form (Cook, 1994). Instead, their availability and benefit are contingent upon the presence of sufficient stomach acid and/or the ionic strength of the intestinal contents during a meal. Absorption of Ca from carbonate sources in patients with achlorhydria has been demonstrated to be significantly impaired if supplementation does not coincide with a meal (Recker, 1985). 

Aggregates from a different source were blended using the mathematical technique to obtain five curves as before. The grading curves are shown in Figure 6. Mix 2 is almost coincident with the upper Fuller limit and mix 4 with the lower limit. Strengths, voids in the mineral aggregate (VMA), and densities are given in Table 1. 

Deflection plates are placed behind the exit slit of the ion source. The vector of the electrostatic field is coaxial with the sector magnetic field vector. The plates permit measurement of the ion kinetic energy distribution in the direction coinciding with the vector of the magnetic analyser field strength. 

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