On systematic errors in spectral line parameters retrieved with the Voigt line profile

Powder diffraction data collected on a nanocrystalline ceria sample within a round robin conducted by the IUCr Commission on Powder Diffraction were analysed by two alternative approaches: (i) whole-powder-pattern modelling based upon a fundamental microstructural parameters approach, and (ii) a traditional whole-powder-pattern fitting followed by Williamson–Hall and Warren–Averbach analysis. While the former gives results in close agreement with those of transmission electron microscopy, the latter tends to overestimate the domain size effect, providing size values about 20% smaller. The origin of the discrepancy can be traced back to a substantial inadequacy of profile fitting with Voigt profiles, which leads to systematic errors in the following line profile analysis by traditional methods. However, independently of the model, those systematic errors seem to have little effect on the volume-weighted mean size.

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Stark Broadening Spectral Line Profile at Different Electric Microfield Distribution Functions

Acta Optica Sinica ◽

10.3788/aos20092902.0529 ◽

2009 ◽

Vol 29 (2) ◽

pp. 529-532

Author(s):

冉俊霞 Ran Junxia ◽

张少朋 Zhang Shaopeng ◽

李红莲 Li Honglian ◽

郝晓辉 Hao Xiaohui ◽

庞学霞 Pang Xuexia

Keyword(s):

Spectral Line ◽

Line Profile ◽

Distribution Functions ◽

Stark Broadening ◽

Spectral Line Profile

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Role of Spectral Line Profile in Laser IR Analysis of Multicomponent Gas Mixtures

Russian Journal of Physical Chemistry B ◽

10.1134/s1990793119050191 ◽

2019 ◽

Vol 13 (5) ◽

pp. 727-738

Author(s):

Sh. Sh. Nabiev ◽

S. V. Ivanov ◽

A. S. Lagutin ◽

L. A. Palkina ◽

S. V. Malashevich ◽

...

Keyword(s):

Spectral Line ◽

Line Profile ◽

Gas Mixtures ◽

Multicomponent Gas ◽

Spectral Line Profile ◽

Ir Analysis

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Measurement of line profiles

Symposium - International Astronomical Union ◽

10.1017/s0074180900151782 ◽

1986 ◽

Vol 118 ◽

pp. 401-412

Author(s):

David F. Gray

Keyword(s):

Spectral Line ◽

High Precision ◽

Line Profile ◽

Line Profiles ◽

Spectral Line Profile ◽

The University

The basic requirements for high precision spectral line profile measurements are reviewed, with the observatory at the University of Western Ontario serving to illustrate several of the points.

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Capabilities of bisector analysis of the Si I 10 827 Å line for estimating line-of-sight velocities in the quiet Sun

Astronomy and Astrophysics ◽

10.1051/0004-6361/201937274 ◽

2020 ◽

Vol 634 ◽

pp. A19 ◽

Cited By ~ 1

Author(s):

S. J. González Manrique ◽

C. Quintero Noda ◽

C. Kuckein ◽

B. Ruiz Cobo ◽

M. Carlsson

Keyword(s):

Spectral Line ◽

Line Profile ◽

Line Of Sight ◽

Solar Telescope ◽

Simple Method ◽

Quiet Sun ◽

Line Intensities ◽

Line Core ◽

Reference Images ◽

Non Local

We examine the capabilities of a fast and simple method to infer line-of-sight (LOS) velocities from observations of the photospheric Si I 10 827 Å line. This spectral line is routinely observed together with the chromospheric He I 10 830 Å triplet as it helps to constrain the atmospheric parameters. We study the accuracy of bisector analysis and a line core fit of Si I 10 827 Å. We employ synthetic profiles starting from the Bifrost enhanced network simulation. The profiles are computed solving the radiative transfer equation, including non-local thermodynamic equilibrium effects on the determination of the atomic level populations of Si I. We found a good correlation between the inferred velocities from bisectors taken at different line profile intensities and the original simulation velocity at given optical depths. This good correlation means that we can associate bisectors taken at different line-profile percentages with atmospheric layers that linearly increase as we scan lower spectral line intensities. We also determined that a fit to the line-core intensity is robust and reliable, providing information about atmospheric layers that are above those accessible through bisectors. Therefore, by combining both methods on the Si I 10 827 Å line, we can seamlessly trace the quiet-Sun LOS velocity stratification from the deep photosphere to higher layers until around logτ = −3.5 in a fast and straightforward way. This method is ideal for generating quick-look reference images for future missions like the Daniel K. Inoue Solar Telescope and the European Solar Telescope, for example.

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