scipp.constants#

Physical and mathematical constants with units. This module a wrapper around scipy.constants and requires the scipy package to be installed.

Mathematical constants:

Physical constants:

`c`	speed of light in vacuum
`speed_of_light`	speed of light in vacuum
`mu_0`	the magnetic constant \(\mu_0\)
`epsilon_0`	the electric constant (vacuum permittivity), \(\epsilon_0\)
`h`	the Planck constant \(h\)
`Planck`	the Planck constant \(h\)
`hbar`	\(\hbar = h/(2\pi)\)
`G`	Newtonian constant of gravitation
`gravitational_constant`	Newtonian constant of gravitation
`g`	standard acceleration of gravity
`e`	elementary charge
`elementary_charge`	elementary charge
`R`	molar gas constant
`gas_constant`	molar gas constant
`alpha`	fine-structure constant
`fine_structure`	fine-structure constant
`N_A`	Avogadro constant
`Avogadro`	Avogadro constant
`k`	Boltzmann constant
`Boltzmann`	Boltzmann constant
`sigma`	Stefan-Boltzmann constant \(\sigma\)
`Stefan_Boltzmann`	Stefan-Boltzmann constant \(\sigma\)
`Wien`	Wien displacement law constant
`Rydberg`	Rydberg constant
`m_e`	electron mass
`electron_mass`	electron mass
`m_p`	proton mass
`proton_mass`	proton mass
`m_n`	neutron mass
`neutron_mass`	neutron mass

In addition to the above variables, scipp.constants also contains the 2018 CODATA recommended values [CODATA2018] database containing more physical constants. The database is accessed using scipp.constants.physical_constants().

CODATA Recommended Values of the Fundamental Physical Constants 2018. https://physics.nist.gov/cuu/Constants/

Functions

physical_constants(key[, with_variance])

Returns the CODATA recommended value with unit of the requested physical constant.