Valid Identifiers for Constants
In all tables, the valid identifiers for units that can be used in TOP-Energy are highlighted in bold type.
Mathematics
| Constant | Identifier (name) |  Definition  | 
|---|---|---|
| Pi 𝜋 (Archimedes’ constant) | PI |  3,14159265358979323846 | 
Light and Sound
| Constant | Identifier (symbol) | Comment |  Definition  | 
|---|---|---|---|
| Speed of light | c | measured in vacuum |  2,99792458·108 m/s | 
| Speed of sound | mach | in dry air under standard conditions |  331,46 m/s | 
Standard State Conditions
| Constant | Identifier (name) | Identifier (symbol) |  Definition  | 
|---|---|---|---|
| Standard temperature | standardtemp | stdtemp |  273.15 K | 
| Standard pressure | atmosphere | atm |  101325 Pa | 
Particle Physics
| Constant | Identifier (name) | Identifier (symbol) | Comment |  Definition  | 
|---|---|---|---|---|
| Gravitational constant | gravity | force | constant of proportionality in the law of gravity |  9,80665 m/s2 | 
| Planck constant | h_planck |  6,62606876·10-34 J s | 
||
| Reduced Planck constant | h_bar |  h_planck/2 PI | 
||
| Elementary charge | e |  1,602176462·10-19 C | 
||
| Electron volt | eV | increase in the kinetic energy of an electron at an acceleration voltage of 1 volt |  1 e V | 
|
| Atomic mass unit | atomicmassunit |  amu  u  | one twelfth of the mass of 12C |  1,66053873·10-27 kg | 
| Chemical atomic mass unit | amu_chem | one sixteenth of the average mass of oxygen in the natural isotope mixture |  1,66026·10-27 kg | 
|
| Physical atomic mass unit | amu_phys | one sixteenth of the mass of the oxygen isotope 16O |  1,65981·10-27 kg | 
|
| Dalton | dalton | common term for the atomic mass unit in biochemistry |  1 u | 
|
| Electron mass | electronmass | m_e |  5,48579911·10-4 u | 
|
| Proton mass | protonmass | m_p |  1,00727646688 u | 
|
| Neutron mass | neutronmass | m_n |  1,00866491578 u | 
|
| Muon mass | muonmass | m_mu |  0,1134289168 u | 
|
| Deuteron mass | deuteronmass | m_d |  2,01355321271 u | 
|
| Alpha particle mass | alphaparticlemass | m_alpha |  4,0015061747 u | 
Chemistry
| Constant | Identifier (name) | Identifier (symbol) | Comment |  Definition  | 
|---|---|---|---|---|
| Avogadro constant | avogadro | N_A | number of particles per amount of substance |  1 gram/amu mol | 
| Gas constant | gasconstant | R |  8,314472 J/mol K | 
|
| Boltzmann constant | boltzmann | k |  1 R/N_A | 
|
| Mole volume | molarvolume | volume of one mole of an ideal gas under standard conditions |  1 mol R stdtemp/atm | 
|
| Loschmidt constant | loschmidt | number of molecules per volume unit of an ideal gas under standard conditions |  1 avogadro mol/molarvolume | 
|
| Stefan–Boltzmann constant | stefanboltzmann | constant of proportionality in the Stefan–Boltzmann law (describes the power radiated from a black body in terms of its temperature) |  PI2 K4/60 hbar3 c2 | 
