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15 Qoldberg and Brown (195O) have shown that rhenium is about 130 times more abundant and that lead is at least 50 times less abundant than was previously assumed. This has created some doubt as to the validity of the data published for the cosmic abundances of the minor constituents of the less abundant elements. Previous to Brown's investigation the values for rhenium and lead were based entirely on the work of I. and W. Noddack. A comparison of their worlc with that of others shows that, in general, data compiled by these authors should not be accepted uncritically. In many cases no other data are available and Qoldschmidt has used their values considering, however, possible sources of error in their determinations. As will be evident from the detailed discussion under individual elements, there are serious sources of error In all data available. The data published in the last twenty years and particularly since the war seem to be generally much more reliable than that published previously. Even certain data of such a reliable Investigator as V. M. Qoldschmidt have been shown to be seriously in error, as for example in the case of lead. Generally, the amounts reported for the rarer elements, particularly in the range of a few parts per million, have decreased with time. Hence in our choice of data we have tended to select lower values rather than higher ones. In some cases we have selected values definitely outside the reported analytical values. It is our expectation tliat many reported analytical data are in error
16 by more than a factor of 10, e.g. Sn, Ag and W« Only further careful analytical work can decide whether our rather arbitrary choices in some cases are Justified. We can say categorically that if some of these choices are incorrect, then our fundamental assumption of considerable smoothness in the abundance curves as a function of mass number is incorrect also. Discussion of elemental abundances All atomic abundances are given relative to Si equal to 10 . Qoldschmidt used silicon equal to 100 and Brown changed this to 10000. We use 10^ in order to get values for the rarer elements which can be written without negative exponentials, or awkward decimal fractions. Plots of logarithms of the abundances, H, against mass numbers. A, are given in Figure 1 and. our selected values are given in Table 3
Page 1 and 2: 05" 9003'9 ,^ r.V- ou 15 -^ CBNTiJA
Page 3 and 4: DISCLAIMER Portions of this documen
Page 5 and 6: o which states that the elements wi
Page 7 and 8: inattention will be drawn to any ev
Page 9 and 10: 6 the proportions 10:1:2- The Nodda
Page 11 and 12: 8 Just in the case of these element
Page 13 and 14: 10 spectral lines on the temperatur
Page 15 and 16: 12 have studied the iron sulfide fr
Page 17: 14 the proportion of the three phas
Page 21 and 22: 18 million times smaller than that
Page 23 and 24: 20 as occurs at other points in the
Page 25 and 26: 22 220 ppm relative to silicon equa
Page 27 and 28: 24 abundances, R, and column three
Page 29 and 30: 26o The heavier rare gases^ Bie rar
Page 31 and 32: 28, the amount is very constant nea
Page 33 and 34: 30o valueso This ratio is 300 hy we
Page 35 and 36: greater constancy in the copper dat
Page 37 and 38: 33 o mass curve we natst assun® ab
Page 39 and 40: 35. Noddack*s value of 1.86 for the
Page 41 and 42: 37 value. Undoubtedly a marked decr
Page 43 and 44: 3Bo meteorites. We have selected a
Page 45 and 46: 40 than that given by Noddack (1955
Page 47 and 48: 42 The average is secured by assumi
Page 49 and 50: 44 these data all appear to be doub
Page 51 and 52: 46 ppm are not presented with great
Page 53 and 54: 48 We adopt values for u235, u^^°
Page 55 and 56: 50 the elements were formed at leas
Page 57 and 58: i»2o for the sum of isobaric abund
Page 59 and 60: 5u« This means that the In^^^ in n
Page 61 and 62: :>6„ of the neutron excess number
Page 63 and 64: dance values fitting into the trend
Page 65 and 66: OUo 56 56 The hjalf life of m , whi
Page 67 and 68: TABLE II 6 Atomic Abundances of the
Page 69 and 70:
TABLE II continued 3 45 Rh 1.3 3,5
Page 71 and 72:
TABLE III Element A N I Log H H 1 H
Page 73 and 74:
21 22 23 24 25 26 27 28 29 Sc Ti V
Page 75 and 76:
TABLE III Continued 5 37 Rb p- 37.
Page 77 and 78:
52 55 5^ 55 56 57 58 Te I Xe Cs Bn
Page 79 and 80:
67 Ho 68 Er 71 Lu 72 Hf 73 Ta 74 W
Page 81:
TABLE III Continued 11 122 124 40 4
Page 86 and 87:
Blbliography-2 Pellenberger, Th.v.,
Page 88 and 89:
Pinson, W.H., Ahrens, L.H. and Fran
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