Reduced Planck constant, Planck constant over 2pi.

value = hbar
[value,sigma] = hbar

hbar returns the value of the reduced Planck constant, h/(2*pi), in SI units (joule*seconds) in value and the standard deviation in sigma (if two output arguments are specified).

The value and the standard deviation are taken from the 2018 CODATA collection of recommended values.

amu, angstrom, avogadro, barn, bmagn, bohrrad, boltzm, clight, echarge, emass, eps0, evolt, faraday, gammae, gfree, hartree, molgas, mu0, nmagn, nmass, planck, pmass, rydberg