the more subtle features of absorption spectra (such as hyperfine structure) is known as Doppler broadening. Rev. This splitting is called fine structure and was one of the first experimental evidences for electron spin. A fine structure with fixed angular quantum number l and total angular momentum quantum number j is split into hyperfine structure components with f taking the possible values j+I, j+I-1, ..., \left\vert{j-I}\right\vert, and the degeneracy of such a level is given by \min\{2j+1,2I+1\}. In this lecture, we will go through the hyperfine structure of atoms. The coupling of nuclear and electronic total angular momentum is explained. Generally the resolution is too poor and the lines are so broadened by high temperature as to mask any hyperfine structure. A 73, 032508 – Published 15 March 2006. The probability that an atom’s velocity Hyperfine structure in the 4 p 5 5 d states of Kr 83 Rupesh Silwal and J. R. Brandenberger Phys. Spectral Line Quadrupole Moment Hyperfine Structure Isotope Shift Reduce Matrix Element These keywords were added by machine and not by the authors. Hydrogen Fine Structure When the familiar red spectral line of the hydrogen spectrum is examined at very high resolution, it is found to be a closely-spaced doublet. We assume a Maxwell distribution of velocities of the atoms in the cell, and again examine only the z-component of the atomic velocities. Hyperfine structure of spectrum lines is not often evident in the visible spectrum of stars. The 1961 A Se I line happens to coincide with the °p12(~) ab sorption line in the (3,0) A-X band, thereby selecting the J=!, N= 1, v = 3 level of the A state.10 To simplify the spectrum and enhance the rf resonance intensities, the hyperfine spectrum is … Hyperfine structure is approximately 1000 times smaller than fine structure. They presented a list of about 500 spectral lines of In II, 325 of which had partially resolved and analyzed hyperfine structure (hfs) patterns. contributions is the work of Paschen and Campbell [2]. optical pumping by an intense atomic spectral line. The splitting of spectral lines caused by nucleon-electron spin interaction. This process is experimental and the keywords may be updated as the learning algorithm improves. Hyperfine Structure of Spectral Lines: Page-1 . Various origins of the hyperfine structure are discussed . The HfS_nh3 procedures included in HfS fit simultaneously the hyperfine structure of the NH3 (J,K)= (1,1) and (2,2) inversion transitions, and perform a standard analysis to derive the NH3 column density, rotational temperature Trot, and kinetic temperature Tk. Cu I spectral lines generally exhibit a total profile width in the range of 2–25 GHz, and the full width at half maximum (Doppler width) of each hyperfine component varies between 0.07 and 0.1 cm −1 depending upon the λ. This spin interaction in turn causes splitting of the fine structure of spectral lines into smaller components called hyperfine structure. HfS fits the hyperfine structure of spectral lines, with multiple velocity components.