Results 11 to 20 of about 873,650 (292)
Proceedings of the International Astronomical Union, 2010 AbstractThe upper main sequence magnetic chemically peculiar (Ap) stars exhibit a non-uniform distribution of chemical elements across their surfaces and with height in their atmospheres. These inhomogeneities, responsible for the conspicuous photometric and spectroscopic variation of Ap stars, are believed to be produced by atomic diffusion operating ...
Oleg Kochukhov
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Magnetic field measurements of sharp-lined Ap stars [PDF]
, 2022 Previous observations suggested that Ap and Bp stars exhibit a bimodal distribution of surface magnetic field strengths and that actually only few or no stars exist with magnetic dipole field strengths below 300 G down to a few Gauss. As the number of Ap
Ilyin, I. +4 more
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THE PHOTOMETRIC STUDY OF TWO FAINT MIRA-TYPE STARS UX CYG AND AP CYG
Odessa Astronomical Publications, 2017 Two faint Mira-type stars were investigated on the Moscow and Odessa plates collections. The new ephemerids are Tmax = 2426875 + 274d.8 · E for AP Cyg and 2442162+568d · E for UX Cyg. For UX Cyg, the multiharmonic variability was detected. Two stars were
Yu. V. Beletskij +2 more
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Absolute Calibration. III. Improved Absolute Calibration for the Visible through the Mid-infrared
The Astronomical Journal, 2023 We propose Sirius as an improved zero-point-defining star and calibrate its spectrum to an accuracy of ∼0.6% in both the visible and infrared. This result is based on a newly derived independent calibration in the visible of similar accuracy to the ...
G. H. Rieke +3 more
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MAGNETIZATION OF STARS VS. THE EFFECTIVE TEMPERATURE
Odessa Astronomical Publications, 2008 Using all published magnetic measurements there were detected some dependences of frequency of occurrence of magnetic field value for all types of peculiarity (Bychkov et al., 2003a, 2008). On the basis of it we normalized these dependences for the most "
V. D. Bychkov, L. V. Bychkova, J. Madej
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Six new rapidly oscillating Ap stars in the Kepler long-cadence data using super-Nyquist asteroseismology [PDF]
, 2019 We perform a search for rapidly oscillating Ap stars in the Kepler long-cadence data, where true oscillations above the Nyquist limit of 283.21 µHz can be reliably distinguished from aliases as a con- sequence of the barycentric time corrections applied ...
Howard, Andrew W +15 more
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RAPID OSCILLATIONS IN THE SPECTRUM OF roAp STARS χ PSC AND γ EQU
Odessa Astronomical Publications, 2017 Results of high time and spectral resolution spectral observations with CCD in 1998-1999 for Ap stars χ Psc and γ Equ were presented. Spectroscopic parameters (Vr, Wλ) of spectral lines SiII, CrI, CrII, FeI, FeII, Hα, Hβ shows that despite of different ...
S. G. Aliev, N. Z. Ismailov
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Automatic Roadside Feature Detection Based on Lidar Road Cross Section Images
Sensors, 2022 The United Nations (UN) stated that all new roads and 75% of travel time on roads must be 3+ star standard by 2030. The number of stars is determined by the International Road Assessment Program (iRAP) star rating module. It is based on 64 attributes for
Ivan Brkić +3 more
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Fundamental Parameters of 10 Ap-Stars [PDF]
, 2023 Представлен результат самосогласованного анализа спектров высокого разрешения для 10 Aр-звезд в диапазоне эффективных температур 7 000—11 000 К. Получены фундаментальные параметры звезд, определен химический состав их атмосфер и оценена стратификация ...
Романовская, А. М. +1 more
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Intermediate Peculiar Stars : The Bp-Ap Si Stars [PDF]
International Astronomical Union Colloquium, 1986 AbstractThis paper contains two parts: 1)A review of the most recent results on the silicon peculiar stars. Five topics will be reviewed: parameters of Bp-Ap Si stars — UV spectrum — spectrophotometry — spectrum variations and flux redistribution -magnetic braking.2)The horizontal diffusion of the silicon in the presence of a magnetic field and, as a ...
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