PyREC scaffolding (from YREC development, 7be4133)/ gmass06.fGlossary

gmass06.f

61 lines · 1 definitions · on GitHub (7be4133)

Python version: gmass06.py, 74 lines, on the right (switch to Python above the code).

Purpose

GMASS06 is the version of GMASS for the 2006 OPAL equation of state. At rp_1 its code was identical to GMASS01 apart from its name; GMASS and GMASS01, for the older tables, are removed since rp_1. It returns the mean mass per nucleus (without electrons), and sets the number fractions of H, He, C, N, O, Ne, the particles per nucleus and the ground-state energy.

How it fits

Called only by ESAC06. No COMMON blocks or modules, no calls.

The method

The metals are split in fixed number proportions $x_\mathrm{C} = 0.2471$, $x_\mathrm{N} = 0.0621$, $x_\mathrm{O} = 0.5284$, $x_\mathrm{Ne} = 0.1624$ (XC, XN, XO, XNE). With atomic masses $A_i$ (AMAS), the number of moles per gram of each species is

$$n_\mathrm{H} = \frac{X}{A_\mathrm{H}},\quad n_\mathrm{He} = \frac{1-X-Z}{A_\mathrm{He}},\quad n_k = f_Z\,x_k,\quad f_Z = \frac{Z}{\sum_k x_k A_k}\ (k = \mathrm{C,N,O,Ne}),$$

and the number fractions are $\mathrm{FRAC}_i = n_i/\sum_j n_j$, stored in the order Ne, O, N, C, He, H (indices 1 to 6). With $Z_i$ the nuclear charges (ANUM) and $E_i$ the ground-state energies of the ions (EION, units not stated in the code),

$$\mathrm{AMOLES} = \sum_i (1+Z_i)\,\mathrm{FRAC}_i,\qquad \mathrm{EGROUND} = \sum_i E_i\,\mathrm{FRAC}_i,\qquad \mathrm{GMASS06} = \sum_i A_i\,\mathrm{FRAC}_i,$$

without the electrons' mass (which GMASS added). FRACZ returns $f_Z$. The mean number of electrons per nucleus, ANUME = AMOLES $- 1$ (line 54↗), is computed but not returned (unused?).

Definitions

functionGMASS06

lines 7–61 · GitHub

Mean mass per nucleus, number fractions, particles per nucleus and ground-state energy for a fixed metal mixture (method above).

Called by ESAC06

Change log

The changes since rp_1

Changed since rp_1. Declarations only: IMPLICIT NONE. GMASS and GMASS01, which the method referred to, are removed, so their equations are given here.