Atomic Spectroscopy Using Constant Deviation Sprectormeter
Atomic Spectroscopy using a Constant Deviation Spectrometer with Fabry-Perot Etalon
Abstract
A constant deviation spectrometer with Fabry-Perot etalon has been used to investigate the various atomic emission characteristics from a Zn-Cd-Hg lamp, a low pressure Hg lamp and a Ne lamp. The Fabry-Perot etalon of Free Spectral Range 0.010 cm-1 was used to resolve the fringes of the Hg 546.0731nm spectral line, and the 594.4834nm, 614.3063nm, 640.2246nm and 650.6528nm spectral lines of the Ne lamp, and study them at very high dispersion. Using the method of exact fractions, an extremely accurate value for the etalon spacing of d=15.077582±0.0000006mm was obtained. The spectral line widths (their full widths at half maximum intensity) of afore mentioned lines were examined, and factors affecting their line broadening discussed. An appreciation has been obtained by the author for the optical resolving power of the Fabry-Perot etalon – despite its simplistic appearance, its ability to explore the atomic structure of atoms so profoundly is testament to its usefulness even in modern science.
1. Introduction
It is well known that electrons can be characterized by a unique set of discrete energy levels [1]. These levels have well defined energies and electrons moving between them must absorb or emit radiation with energy equal to the difference between them. Atomic emission lines arise from an electron returning to a lower state of excitation. A photon with energy equal to the energy difference between the levels is released in the process. The frequency f at which the spectral line occurs is related to the photon energy E by Planck's law �� = ℎ�� where h is Planck's constant = 6.626068 × 10-34 m2 kg / s. (1)
1
Atomic Spectroscopy using a Constant Deviation Spectrometer with Fabry-Perot Etalon
Thus the wavelength of the light emitted from a source can be used to determine various physical parameters about the source. Spectroscopy is the physical separation of
Abstract
A constant deviation spectrometer with Fabry-Perot etalon has been used to investigate the various atomic emission characteristics from a Zn-Cd-Hg lamp, a low pressure Hg lamp and a Ne lamp. The Fabry-Perot etalon of Free Spectral Range 0.010 cm-1 was used to resolve the fringes of the Hg 546.0731nm spectral line, and the 594.4834nm, 614.3063nm, 640.2246nm and 650.6528nm spectral lines of the Ne lamp, and study them at very high dispersion. Using the method of exact fractions, an extremely accurate value for the etalon spacing of d=15.077582±0.0000006mm was obtained. The spectral line widths (their full widths at half maximum intensity) of afore mentioned lines were examined, and factors affecting their line broadening discussed. An appreciation has been obtained by the author for the optical resolving power of the Fabry-Perot etalon – despite its simplistic appearance, its ability to explore the atomic structure of atoms so profoundly is testament to its usefulness even in modern science.
1. Introduction
It is well known that electrons can be characterized by a unique set of discrete energy levels [1]. These levels have well defined energies and electrons moving between them must absorb or emit radiation with energy equal to the difference between them. Atomic emission lines arise from an electron returning to a lower state of excitation. A photon with energy equal to the energy difference between the levels is released in the process. The frequency f at which the spectral line occurs is related to the photon energy E by Planck's law �� = ℎ�� where h is Planck's constant = 6.626068 × 10-34 m2 kg / s. (1)
1
Atomic Spectroscopy using a Constant Deviation Spectrometer with Fabry-Perot Etalon
Thus the wavelength of the light emitted from a source can be used to determine various physical parameters about the source. Spectroscopy is the physical separation of