HYPERFINE-DEPENDENT gf -VALUES OF Mn I LINES IN THE 1.49-1.80 μm H BAND

Abstract

The three Mn i lines at 17325, 17339, and 17349 Å are among the 25 strongest lines (log(gf ) > 0.5) in the H band. They are all heavily broadened due to hyperfine structure, and the profiles of these lines have so far not been understood. Earlier studies of these lines even suggested that they were blended. In this work, the profiles of these three infrared (IR) lines have been studied theoretically and compared to experimental spectra to assist in the complete understanding of the solar spectrum in the IR. It is shown that the structure of these lines cannot be described in the conventional way using the diagonal A and B hyperfine interaction constants. The off-diagonal hyperfine interaction not only has a large impact on the energies of the hyperfine levels, but also introduces a large intensity redistribution among the hyperfine lines, changing the line profiles dramatically. By performing large-scale calculations of the diagonal and off-diagonal hyperfine interaction and the gf -values between the upper and lower hyperfine levels and using a semi-empirical fitting procedure, we achieved agreement between our synthetic and experimental spectra. Furthermore, we compare our results with observations of stellar spectra. The spectra of the Sun and the K1.5 III red giant star Arcturus were modeled in the relevant region, 1.73-1.74 μm, using our theoretically predicted gf -values and energies for each individual hyperfine line. Satisfactory fits were obtained and clear improvements were found using our new data compared with the old available Mn i data. A complete list of energies and gf -values for all the 3d 5 4s( 7 S)4d e 6 D -3d 5 4s( 7 S)4f w 6 F hyperfine lines are available as supporting material, whereas only the stronger lines are presented and discussed in detail in this paper.

HUBBLE SPACE TELESCOPENEAR-ULTRAVIOLET SPECTROSCOPY OF BRIGHT CEMP-sSTARS

“…The Robospect line lists were based on the compilation of Roederer et al (2012), and data retrieved from the VALD database (Kupka et al 1999) and the National Institute of Standards and Technology Atomic Spectra Database (NIST; Kramida et al 2013). The SPECTREdsg and THIMBLES line lists are based on those used in Ivans et al (2003Ivans et al ( , 2006, supplemented and updated by the work of Blackwell-Whitehead & Bergemann (2007), Nilsson & Ivarsson (2008), Meléndez & Barbuy (2009), Simmerer et al (2013) Wood et al (2013), Lawler et al (2014), Ruffoni et al (2014), Wood et al (2014a,b), and Andersson et al (2015).…”

Hyperfine structures and Landé gJ-factors for n=2 states in beryllium-, boron-, carbon-, and nitrogen-like ions from

“…Higher order terms are much smaller and can often be neglected. By looking at (6), it comes naturally that this operator does not commute neither with the total angular momentum of the electrons J nor with the total angular momentum of the nucleus I, but with the total atomic angular momentum F=I+J. Denoting the nuclear wave function by |κπIM I , where π, I and M I are, respectively, the parity, the total angular momentum and its projection, the coupled states are expressed as…”

“…Hyperfine interaction is also important in astrophysics, high resolution solar, stellar spectra reveal isotope shifts and hyperfine structures of many spectral lines. To correctly interpret the spectra it is necessary to include isotope shifts and hyperfine structures in a theoretical modeling of the line profiles [5,6]. Hyperfine interaction is also of theoretical interest and is a valuable and sensitive probe of both electron correlation and QED effects [7][8][9].…”

Division B Commission 14 Working Group: Atomic Data

“…Al II (HFS): [26], Ar IX: [277], B II: [208], Br III: [140], Cl I: [300], Co II (forbidden): [256], Dy I: [292], Eu I (HFS,IS): [2,102,103,104], Fe VIII-IX: [230], Fe VIII-XVI: [37], Fe XI: [66], Fe XIII: [62], Fe XVI: [36], Fe XVII: [63], Fe XVIII: [54], Fe XVIII-XXV: [254], Gd I (IS,HFS): [145], I I: [124], K I: [51], K III: [22], La I: [106], Li I: [50], Mg VII-VIII: [177], Mn I (HFS): [25,165], Mn II : [46], N III: [112], Na I: [52], Nb I: [72,235], Nb I (HFS): [95], Nd II (HFS): [28], Ne IV : [170], Ni I: [288,291], O I: [204], O VI: [341], P II: [153], Pr I (HFS): [107,282,319], Pr II: [21], Pr II (HFS): [20], Ru I (IS,HFS): ...…”