Results 21 to 30 of about 36,313 (321)
Journal of Applied Clinical Medical Physics, Volume 23, Issue 12, December 2022., 2022 Abstract Purpose The aim of this work was to evaluate the SunCHECK PerFRACTION, the software for in vivo monitoring using EPID images. Materials/Methods First, the PerFRACTION ability to detect errors was investigated simulating two situations: (1) variation of LINAC output and (2) variation of the phantom thickness.
Samuel Ramalho Avelino +3 more
wiley +1 more source
CHIMERA Occultation Constraints on the Abundance of Kilometer-scale Kuiper Belt Objects [PDF]
Astron.J. 166 (2023) 242, 2023 Occultations provide indirect sensitivity to the number density of small Kuiper Belt objects (KBOs) too faint to directly detect telescopically. We present results from the Caltech HI-speed Multicolor camERA (CHIMERA) survey with the Palomar Hale Telescope, which monitored stars over the central 5'x5' of the M22 globular cluster along the ecliptic ...
arxiv +1 more source
Satellite shadows through stellar occultations [PDF]
A&A 667, A45 (2022), 2022 The impact of mega-constellations of satellites in low-Earth orbit during nighttime optical observations is assessed. Orbital geometry is used to calculate the impact of stellar occultations by satellites on the photometry of individual stars as well as the effect on the photometric calibration of wide-field observations.
arxiv +1 more source
Manuels scolaires d’éducation à la citoyenneté au collège et problématique du développement durable, pour une analyse du curriculum prescrit d’instruction civique au Gabon [PDF]
Akofena, 2022 Résumé : La présente contribution se donne pour objectif d’interroger l’éducation à la citoyenneté au collège dans les établissements d’enseignement secondaire public.
Orphée Martial SOUMAHO MAVIOGA & Dany Daniel BEKALE
doaj
Remote Sensing, 2021 The development of small-satellite technologies allows the low Earth orbit intersatellite link (LEO-LEO) occultation method to observe the Earth’s atmosphere with global coverage and acceptable costs using electromagnetic signals, in which the L/X/K/M ...
Congliang Liu +10 more
doaj +1 more source
Design and Simulation of Stellar Occultation Infrared Band Constellation
Remote Sensing, 2022 This study provides an in-depth analysis of the characteristics of stellar occultation events. Using 10 target star sources, the influence of orbital elements on the number, duration, and distribution of stellar occultation events was simulated and ...
Qinglin Zhu +3 more
doaj +1 more source
Boundary diffraction wave integrals for diffraction modeling of external occulters [PDF]
Optics Express, Vol. 20, Issue 14, pp. 15196-15208 (2012), 2012 An occulter is a large diffracting screen which may be flown in conjunction with a telescope to image extrasolar planets. The edge is shaped to minimize the diffracted light in a region beyond the occulter, and a telescope may be placed in this dark shadow to view an extrasolar system with the starlight removed.
arxiv +1 more source
Research on Stellar Occultation Detection with Bandpass Filtering for Oxygen Density Retrieval
Remote Sensing, 2023 Stellar occultation instruments detect the transmission of stellar spectra through the planetary atmosphere to retrieve densities of various atmospheric components.
Zheng Li +6 more
doaj +1 more source
Sensors, 2018 The Atmospheric Infrared Ultraspectral Sounder (AIUS), the first high-resolution (0.02 cm−1) solar occultation sounder, aboard GF5, was launched in May 2018 from China.
Hongmei Wang +9 more
doaj +1 more source
Occultation Searches for Kuiper Belt Objects [PDF]
Astrophys.J. 587 (2003) L125, 2003 The occultation of background stellar sources by foreground Kuiper Belt Objects (KBOs) can be used to survey physical properties of the KBO population. We discuss statistics related to a KBO occultation survey, such as the event duration distribution, and suggest that occultation searches can be effectively used to probe the KBO size distribution below
arxiv +1 more source