Victor Schumann (21 December 1841 – 1 September 1913) was a

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and spectroscopist who in 1893 discovered the vacuum ultraviolet. Schumann studied the

extreme ultraviolet Extreme ultraviolet radiation (EUV or XUV) or high-energy ultraviolet radiation is electromagnetic radiation in the part of the electromagnetic spectrum spanning wavelengths shorter than the hydrogen Lyman-alpha line from 121 nm down to ...

region of the

electromagnetic spectrum The electromagnetic spectrum is the full range of electromagnetic radiation, organized by frequency or wavelength. The spectrum is divided into separate bands, with different names for the electromagnetic waves within each band. From low to high ...

. For this, he used a prism and lenses in fluorite instead of

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

allowing himself to be the first to measure spectra below 200 nm.

Oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

gas would absorb the radiation with a wavelength below 195 nm, but Schumann placed the entire apparatus under vacuum. He prepared his own

photographic plate Photographic plates preceded film as the primary medium for capturing images in photography. These plates, made of metal or glass and coated with a light-sensitive emulsion, were integral to early photographic processes such as heliography, d ...

s with a reduced layer of gelatin. He published on the hydrogen line in the spectrum of Nova Aurigae and in the spectrum of

vacuum tubes A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...

.Schumann V, ''Astronomy and astrophysics'', Volume 12, Carleton College (Northfield, Minn.). Goodsell Observatory His work opened the way to

atomic emission spectroscopy Atomic emission spectroscopy (AES) is a method of chemical analysis that uses the intensity of light emitted from a flame, plasma, arc, or spark at a particular wavelength to determine the quantity of an element in a sample. The wavelength of ...

, leading eventually to the discovery of the hydrogen spectral lines series ( Lyman series) by Theodore Lyman in 1914.

References

External links

*
Victor Schumann at encyclopedia.com
{{DEFAULTSORT:Schumann, Victor 19th-century German physicists People from the Kingdom of Saxony 1841 births 1913 deaths German spectroscopists People from Leipzig (district)