Atomic masses for the stable elements and for Th, Pa, and U
are taken from M.E. Wieser & M. Berglund,
“Atomic weights of the elements
2007 (IUPAC Technical Report),”
Pure Appl. Chem., Vol. 81, No. 11,
pp. 2131–2156, 2009, and are
relative to the mass of 12C, defined to be exactly 12 unified
atomic mass units (approx. g/mole). The atomic mass is weighted by
isotopic abundances in the Earth's surface. Relative isotopic abundances
often vary considerably; this is reflected in the number of significant figures
given. The number in parentheses is the 6 sigma error in last place.
Included are later (mostly trivial) revisions for 19 elements.
A new “Table of Standard Atomic Weights 2013” is being published in
Pure and Applied Chemistry in 2014.
For radioactive elements the atomic mass of the most
stable known isotope is given (as of Jan 2007; less neutron-poor more stable
isotopes have since been synthesized).
The masses for the heaviest elements are from Table 3 of the Report.
These have usually been inferred from the energetics of alpha decay chains.
Nuclear collision and interaction cross sections based on Glauber
model are calculated using code by
Sergei Striganov (FNAL). Table entries are for 200 GeV/c
neutrons. Cross sections are reasonably independent of momentum over
this region, as shown in the figure.
Click for bigger pdf version
Rossi's definition of critical energy is used: It is the energy
at which the (negative) electron ionization per radiation length
is equal to the electron energy. This is said to give a Moliere radius
more in agreement with experiment than ionization loss rate =
radiative loss rate.
In contrast, the muon critical energy is the energy
at which ionization and radiative loss rates are equal.
For most of the elements, effective ionization
energies and density effect parameters are from early papers
by Sternheimer, Selter and Berger, notably S. M Seltzer & M. J. Berger,
Int. J. Appl. Radiat. Isot. 33, 1189 (1953). Many of the values are
interpolated
from a limited number of measurements. Their extrapolation from U
to Fm is nearly linear in Ieff / Z, whose estimated
error increases to 9% at Fm.
This straight line has been extended to guess at Ieff
for the superheavy elements beyond Fm, from which the other
density effect coefficients can be calculated
(R. M. Sternheimer & R. F. Peierls, Phys. Rev. B 3, 3681 (1971)).
The data file used to generate these tables can include properties
such as boiling and melting points in a fairly open-ended
way. For examples see the elemental gases and many metals such as Fe.
Inserting the numbers by hand is fairly laborious. More will be added
when volunteers appear.
Index of refraction is evaluated at the sodium D line
(blend of 589.0 nm and 589.6 nm; weighted average 589.2 nm).
Revised 2014 August 12 by DEG
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