electric_charge¶
-
plasmapy.atomic.
electric_charge
(particle: plasmapy.atomic.particle_class.Particle) → astropy.units.quantity.Quantity¶ Return the electric charge (in coulombs) of a particle.
Parameters: particle (
str
) – String representing an element or isotope followed by integer charge information.Returns: charge – The electric charge in coulombs.
Return type: Raises: InvalidParticleError
– If the argument does not correspond to a valid particle or contradictory information is provided.ChargeError
– If charge information for the particle is not available.AtomicWarning
– If the input represents an ion with an integer charge that is below -3.
Notes
This function supports two formats for integer charge information.
The first format is a string that has information for the element or isotope at the beginning, a space in between, and the integer charge information in the form of an integer followed by a plus or minus sign, or a plus or minus sign followed by an integer.
The second format is a string containing element information at the beginning, following by one or more plus or minus signs.
This function returns -1.6021766208e-19 C for electrons and 1.6021766208e-19 C for positrons.
Examples
>>> electric_charge('p+') <<class 'astropy.constants.codata2014.EMCODATA2014'> name='Electron charge' value=1.6021766208e-19 uncertainty=9.8e-28 unit='C' reference='CODATA 2014'> >>> electric_charge('H-') <Quantity -1.60217662e-19 C>