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Julius Plücker



Elberfeld 16.June.1801 - Bonne 22.May.1868
Study of electrical discharges in the rarefied gas


Mathematician and physical. In physics major research concerned the spectroscopy and electrical discharges in the rarefied gases. To conduct this research is availed themselves of the collaboration of Geissler to produce cathode ray tubes vacuum. In 1858 notes that in a Cathode ray tube when the gas pressure decreases increases the brightness produced by same. In 1859 discovers that katode ray are deflected by magnetic fields.

In his studies physical concerned main spectroscopy and electrical discharges in the rarefied gases. In its spectroscopic studies Pulcker came to anticipate and Robert Bunsen Gustav R. Kirchhoff that the lines were spectral characteristics for each chemical, also observed for the first three lines of the spectrum of hydrogen and said that the same substance may have different spectra at different temperatures. Regarding the study of electrical discharges in the rarefied gas, in its experiments Plucker noted that approaching a magnet tube discharge its position glow on the walls changed. He Inferred  so that the discharge was diverted by magnetic fields. His experiments were important but those who brought him to observe that the luminescence which was produced changed depending on the vacuum that had been done. Lowering fact, the gas pressure inside the tube had noted that the luminescence tube decreased while the glass opposite the cathode issued a greenish light. Was as if that is the cathode issued something and this issue hits the opposite side to the cathode.