Results 1 to 10 of about 344,061 (314)
Long-Term Optical Monitoring of Broad-Line AGNs (LoTerm AGN): Case Study of NGC 3516
Physics, 2023 Properties of the broad line region (BLR) in active galactic nuclei (AGNs) are commonly used to estimate the mass of the supermassive black hole (SMBH) that powers an AGN. However, the understanding of the physics behind the BLR remains incomplete.
Dragana Ilić +22 more
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Helium Line Emissivities in the Solar Corona [PDF]
The Astrophysical Journal, 2020 Abstract We present new collisional-radiative models (CRMs) for helium in the quiescent solar corona and predict the emissivities of the He and He+ lines to be observed by DKIST, Solar Orbiter, and Proba-3. We discuss in detail the rates we selected for these models, highlighting several shortcomings we have found in previous work. As no
G. Del Zanna +3 more
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Quasar Emission - Line Strengths [PDF]
Symposium - International Astronomical Union, 1989 The strongest lines have been measured in 73 quasar spectra from the archives of the International Ultraviolet Explorer Satellite. The optically bright quasars observed with IUE were typically discovered by powerful radio emission or ultraviolet excess.
Richard Green +2 more
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EVOLUTION OF [O III] λ5007 EMISSION-LINE PROFILES IN NARROW EMISSION-LINE GALAXIES [PDF]
The Astrophysical Journal, 2011 33 pages, 8 figures, and 5 tables, to be published in ...
Wang, J., Mao, Y. F., Wei, J. Y.
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Integral Field Spectroscopy of Planetary Nebulae with MUSE
Galaxies, 2020 The Multi-Unit Spectroscopic Explorer (MUSE) is a large integral field unit mounted on the ESO Very Large Telescope. Its spatial (60 arcsecond field) and wavelength (4800–9300Å) coverage is well suited to detailed imaging spectroscopy of extended ...
Jeremy R. Walsh, Ana Monreal-Ibero
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Price and Portcall Frequency Competition in Sea-and-Land transportation supply chain under Carbon Emission Reduction Target [PDF]
SHS Web of Conferences, 2023 For carbon emission reduction by ports and shipping lines under sea-and-land transportation mode, to build a two-stage transportation supply chain model consisting of two competing ports and one shipping line The profit functions of ports and shipping ...
Wang Yueyi, Han Hao
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Characterizing Spectral Channels of Visible Emission Line Coronagraph of Aditya-L1
Frontiers in Astronomy and Space Sciences, 2021 Aditya-L1 is India’s first solar mission with the Visible Emission Line Coronagraph (VELC), which consists of three spectral channels taking high-resolution spectroscopic observations of the inner corona up to 1.5 Rʘ at 5,303, 7,892, and 10,747 Å.
Ritesh Patel +13 more
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Extreme Quasars as Distance Indicators in Cosmology
Frontiers in Astronomy and Space Sciences, 2020 Quasars accreting matter at very high rates (known as extreme Population A [xA] quasars, possibly associated with super-Eddington accreting massive black holes) may provide a new class of distance indicators covering cosmic epochs from present day up to ...
Deborah Dultzin +10 more
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Studying Nearby Galactic Planetary Nebulae with MUSE: On the Physical Properties of IC 418
Galaxies, 2022 Spectroscopic mapping of planetary nebulae (PNe) is particularly useful to capture the richness in terms of physical and chemical properties that exist in these objects.
Ana Monreal-Ibero , Jeremy R. Walsh
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CORONAL EMISSION LINES AS THERMOMETERS [PDF]
The Astrophysical Journal, 2009 Accepted by ApJ, November ...
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