Paschen series

physics

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July 23, 2026

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The Paschen series is a set of related wavelengths of electromagnetic radiation emitted by energized atoms, specifically hydrogen. These spectral lines occur when an electron in a hydrogen atom transitions from a higher energy level to the third energy level (n=3). The Paschen series is located in the infrared region of the electromagnetic spectrum. Similar to other spectral series, its wavelengths can be described by a mathematical formula involving the Rydberg constant. The Paschen series is one of five spectral series observed in hydrogen, with the Balmer series being the most well-known in the visible spectrum.1

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spectral line series
…the United States and Friedrich Paschen of Germany. The Lyman series lies in the ultraviolet, whereas the Paschen, Brackett, and Pfund series lie in the infrared. Their formulas are similar to Balmer’s except that the constant term is the reciprocal of the square of 1, 3, 4, or 5, instead…
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…the United States and Friedrich Paschen of Germany. The Lyman series lies in the ultraviolet, whereas the Paschen, Brackett, and Pfund series lie in the infrared. Their formulas are similar to Balmer’s except that the constant term is the reciprocal of the square of 1, 3, 4, or 5, instead…
Read More