Units
The following table list the units available for use in the
configuration files. All units are consistent with the
scipy.constants
values. Radius
values are the nominal equatorial values adopted in [Prsa2016]. Mass
values are consistent with the nominal mass parameter from [Prsa2016]
and a gravitational constant of \(G=6.67408\times10^{-11}\) m3 kg-1 s-2 (same value used in
scipy.constants
and astropy.constants
).
Quantity |
Unit name |
CGS Value |
Description |
Reference |
---|---|---|---|---|
Length |
A |
1.0e-08 |
Angstrom |
|
nm |
1.0e-07 |
Nanometer |
||
um |
1.0e-04 |
Micron |
||
mm |
1.0e-01 |
Millimeter |
||
cm |
1.0 |
Centimeter |
||
m |
1.0e+02 |
Meter (MKS unit) |
||
km |
1.0e+05 |
Kilometer |
||
au |
1.49597e+13 |
Astronomical unit |
||
pc |
3.08568e+18 |
Parsec |
||
rearth |
6.3781e+08 |
Earth radius |
||
rjup |
7.1492e+09 |
Jupiter mean radius |
||
rsun |
6.957e+10 |
Sun radius |
||
Mass |
me |
9.10938e-28 |
Electron mass |
|
amu |
1.66054e-24 |
Unified atomic mass |
||
gram |
1.0 |
Gram |
||
kg |
1.0e3 |
Kilogram (MKS unit) |
||
mearth |
5.97236e+27 |
Earth mass |
||
mjup |
1.898187e+30 |
Jupiter mass |
||
msun |
1.988475e+33 |
Sun mass |
||
Pressure |
barye |
1.0 |
Barye |
|
mbar |
1000.0 |
Millibar |
||
pascal |
1.0e+05 |
Pascal (MKS unit) |
||
bar |
1.0e+06 |
Bar |
||
atm |
1.01e+06 |
Atmosphere |
||
Time |
sec |
1.0 |
Second |
|
min |
60.0 |
Minute |
||
hour |
3600.0 |
Hour |
||
day |
86400.0 |
Day |
||
Unitless |
none |
1.0 |
None |
|
percent |
1.0e-2 |
Percent |
||
ppt |
1.0e-3 |
Parts per thousand |
||
ppm |
1.0e-6 |
Parts per million |
||
Number density |
amagat |
2.6867811e+19 |
Loschmidt constant |
The user can access these units and other constants during a Python
interactive seesion via the pyratbay.constants
sub-module, for example:
import pyratbay.constants as pc
print('1e-5 bar is {:.1f} barye'.format(1e-5*pc.bar))
1e-5 bar is 10.0 barye