Paschen series

In physics, the Paschen series (also called Ritz-Paschen series) is the series of transitions and resulting emission lines of the hydrogen atom as an electron goes from n ≥ 4 to n = 3, where n refers to the principal quantum number of the electron. The transitions are named sequentially by Greek letter: n = 4 to n = 3 is called Paschen-alpha, 5 to 3 is Paschen-beta, 6 to 3 is Paschen-gamma, etc.

They are named after the Austro-German physicist Friedrich Paschen who first observed them in 1908.

Paschen series, in the infrared, measured lines with wavelengths (nm):

n	4	5	6	7	8	9	10	11	12	13	$\infty$
Wavelength (nm)	1874.5	1281.4	1093.5	1004.6	954.3	922.6	901.2	886.0	874.8	866.2	820.1

See also

• Bohr model
• H-alpha
• Rydberg formula

External references

• Paschen series (animation)