Paschen series
(hydrogen lines for electrons settling from n > 3 to n = 3)
The Paschen series is the set of
emission lines from atomic hydrogen gas,
due to electrons descending from
an electron shell of number n greater than 3 down to that of n = 3,
or the analogous absorption lines when absorbed electromagnetic radiation (EMR)
makes electrons do the opposite.
It is one of the hydrogen line series, such as
the Lyman series and Balmer series, and is
named after Friedrich Paschen.
The lines are within near infrared and some are within atmospheric windows,
so given no redshift, some of the lines in astronomical sources may
be viewed from ground telescopes while others are blocked.
Lines:
- 4 -> 3: 1875 nm
- 5 -> 3: 1282 nm
- 6 -> 3: 1094 nm
- 7 -> 3: 1005 nm
- 8 -> 3: 995 nm
- 9 -> 3: 923 nm
- ...
- infinity -> 3: 820 nm
Formula for wavelengths:
1/wavelength = RH ( 1/9 - 1/n² )
(Paschen,hydrogen,line series,lines,spectrum)
Further reading:
https://en.wikipedia.org/wiki/Hydrogen_spectral_series
http://dept.harpercollege.edu/chemistry/chm/100/dgodambe/thedisk/spec/5back5.htm
http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/hydspec.html
https://www.nist.gov/system/files/documents/srd/jpcrd382009565p.pdf
WaveL | Freq | Photon Energy | | |
820nm | 366THz | 1.6eV | begin | Paschen series |
1875nm | 160THz | 661meV | end | Paschen series |
|
Referenced by pages:
hydrogen (H)
spectral line
Index