# A routine to calculate the Radiation Length of a Molecule

## Abstract

RdLength calculates the Radiation Length
of a single molecule based on its empirical formula.
The unit used is g/cm2 (gram/centimeter square).

The method used is the one proposed by Tsai. Y.S.,
on Rev. Mod. Physics, 46, p.815, 1974. It
is the same method used by the Particle Physics Booklet.

The program also displays the formula needed to
calculate the Radiation Length of a multi-molecular
material. This is:

1
------------------------------------------------------
_ _
| (percent - in weight- of molecule "x" on material) |
Summation of | -------------------------------------------------- |
|_ (Radiation Length of molecule "x" in g/cm2) _|

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November 10th, 1996