Results 11 to 20 of about 5,257,093 (276)
Spectral Line Shapes of He I Line 3889 Å
Atoms, 2014 Spectral line shapes of neutral helium 3889 Å(23S–33P) transition line are calculated by using several theoretical methods. The electronic contribution to the line broadening is calculated from quantum statistical many-particle theory by using ...
Banaz Omar +8 more
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Theory and assessment of an improved power spectral density estimator [PDF]
, 1990 This thesis is concerned with the processing of time domain signals received by a single sensor. An example of such signals is the radar return, which is used in one way or another to estimate the power spectral density a frequency representation of ...
Ali, Ali Abbas
core +7 more sources
Spectral Domain Low- Coherence Interferometry for On-line Surface Inspection [PDF]
, 2013 We present an on-line surface measurement technique based on spectral domain low-coherence interferometry (SD-LCI), which can obtain a one dimensional surface profile with just one shot.
Gao, F., Jiang, Xiang, Tang, Dawei
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Discrete time model of self-oscillations with spectral line widening
Физика волновых процессов и радиотехнические системы, 2022 An algorithm for generating quasi-harmonic self-oscillations with a uniformly widened spectral line is presented. The algorithm is based on the equation of motion of the Thomson-type DT-oscillator, which introduced a random effect in the form of band ...
Valery V. Zaitsev +2 more
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Spectral Line Depth Variability in Radial Velocity Spectra [PDF]
, 2022 Stellar active regions, including spots and faculae, can create radial velocity (RV) signals that interfere with the detection and mass measurements of low mass exoplanets.
Plavchan, Peter +5 more
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Spectral Line VLBI Studies Using the ngEHT
Galaxies, 2023 Spectroscopy in the mm/sub-mm wavelength range is a powerful tool to study the gaseous medium in various astrophysical environments. The next generation Event Horizon Telescope (ngEHT) equipped with a wide-bandwidth backend system has great potential for
Dong-Jin Kim, Vincent Fish
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“Structure of Spectral Lines” [PDF]
Nature, 1947 In Nature of August 23, p. 244, Dr. D. A. Jackson reviews my recent book on “High-Resolution Spectroscopy” (Methuen, 1947). After considerable hesitation and with much reluctance, I feel compelled to comment on several misrepresentations made by Dr. Jackson.
S, TOLANSKY, D A, JACKSON
openaire +2 more sources
On line spectral frequencies [PDF]
IEEE Signal Processing Letters, 2003 The commonly used line spectral frequencies form the roots of symmetric and antisymmetric polynomials constructed from a linear predictor. We provide a new, simpler proof that the symmetric and antisymmetric polynomials can be regarded as optimal constrained predictors that correspond to predicting from the low-pass and high-pass filtered signal ...
W. Bastiaan Kleijn +2 more
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S-type Stars: Line List for the A2Π–X2Σ+ Band System of LaO
The Astrophysical Journal, 2023 LaO bands are found in the spectra of cool S-type stars. The bands of the A ^2 Π–X ^2 Σ ^+ transition with $v^{\prime} \leqslant 3$ and v ″ ≤ 4 are rotationally analyzed, providing spectroscopic constants for the A ^2 Π state.
P. F. Bernath +2 more
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The Astrophysical Journal Supplement Series, 2023 Using high-resolution spectra of Ni ii recorded using Fourier transform (FT) spectroscopy of continuous, nickel–helium hollow cathode discharge sources in the region 143–5555 nm (1800–70,000 cm ^−1 , the analysis of 1016 Ni ii lines confirmed and ...
Christian P. Clear +4 more
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