Lyman limit

{{Short description|Wavelength associated with hydrogen ionisation}}

In physics and chemistry, the Lyman limit is the short-wavelength end of the Lyman series of hydrogen emission lines at {{convert|91.13|nm|Å|abbr=on}}. The associated photon energy, 13.6 eV, corresponds to the energy required for an electron in the hydrogen ground state to escape from the electric potential barrier that originally confined it, thus creating a hydrogen ion.{{cite book | last=Ridpath | first=Ian | title=A dictionary of astronomy | publisher=Oxford University Press | publication-place=Oxford | year=2012 | isbn=978-0-19-960905-5 | page=282}} This energy is equivalent to the Rydberg constant.