Results 41 to 50 of about 292,162 (290)
Comparative analysis of three mode-selection methods for solid-state lasers [PDF]
E3S Web of Conferences, 2021 In the Nd3+:YAG pulsed Q-switched laser system, the selective output of several low order modes of TEM00, TEM01 and TEM11 is realized by adding a iris diaphragm, a telescope or a Gaussian mirror at an appropriate position in the resonator, and the three ...
Sun Yan
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Remote Sensing, 2022 Telescopic observations of Mercury consistently report systematic variations of the normalized spectral slope of visible-to-near-infrared reflectance spectra.
Kay Wohlfarth, Christian Wöhler
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Science case for the Einstein telescope [PDF]
Journal of Cosmology and Astroparticle Physics, 2019 The Einstein Telescope (ET), a proposed European ground-based gravitational-wave detector of third-generation, is an evolution of second-generation detectors such as Advanced LIGO, Advanced Virgo, and KAGRA which could be operating in the mid 2030s.
M. Maggiore +17 more
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Freeform Wide Field-of-View Spaceborne Imaging Telescope: From Design to Demonstrator
Sensors, 2022 Wide field-of-view imaging optics offer a huge potential for space-based Earth observation enabling the capture of global data. Reflective imaging telescopes are often favored, as they do not show chromatic aberrations and are less susceptible to ...
Luca Schifano +7 more
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Black holes with scalar hair in light of the Event Horizon Telescope [PDF]
Journal of Cosmology and Astroparticle Physics, 2020 Searching for violations of the no-hair theorem (NHT) is a powerful way to test gravity, and more generally fundamental physics, particularly with regards to the existence of additional scalar fields.
Mohsen Khodadi +3 more
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Low Vision Aids: Visual Outcomes and Barriers in Children with Low Vision
Delhi Journal of Ophthalmology, 2019 Aims: To study the demographic profile, cause of low vision, visual outcome and the barriers in using low vision aids (LVA). Design: Prospective observational clinical study.
V. R. Venkataramanan +5 more
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Active optics: deformable mirrors with a minimum number of actuators [PDF]
Journal of the European Optical Society-Rapid Publications, 2012 We present two concepts of deformable mirror to compensate for first order optical aberrations. Deformation systems are designed using both elasticity theory and Finite Element Analysis in order to minimize the number of actuators.
Laslandes M., Hugot E., Ferrari M.
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Remote Sensing, 2022 The paper presents the results of analysis of astroclimatic conditions in the Big Telescope Alt-azimuthal (BTA) region (40°N–50°N; 35°E–55°E). Using data from the European center for medium-range weather forecast ReAnalysis (ERA-5), we estimated the ...
Artem Yu. Shikhovtsev +8 more
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Probing Diversity of Type II Supernovae with the Chinese Space Station Telescope
Universe, 2023 Type II supernovae (SNe II), which show abundant hydrogen in their spectra, belong to a class of SNe with diverse observed properties. It is commonly accepted that SNe II are produced by core collapse and explosion of massive stars.
Han Lin, Jujia Zhang, Xinghan Zhang
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First M87 Event Horizon Telescope Results. III. Data Processing and Calibration [PDF]
Astrophysical Journal, 2019 We present the calibration and reduction of Event Horizon Telescope (EHT) 1.3 mm radio wavelength observations of the supermassive black hole candidate at the center of the radio galaxy M87 and the quasar 3C 279, taken during the 2017 April 5–11 ...
Kazunori Akiyama +216 more
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