Results 71 to 80 of about 8,745 (214)
Underwater view from the Photosphere, Bahamas, 1914
, 1914 Underwater garden in the Bahamas as seen from the Williamson Photosphere, 1914.https://digitalcommons.chapman.edu/jonathan_silent_film/2186/thumbnail ...
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Thermal Bifurcation Of the Outer Photosphere [PDF]
Symposium - International Astronomical Union, 1990 The degree of thermal heterogeneity at the base of the solar chromosphere is substantially beyond that simulated in the best-available multi-component models; casting serious doubts on inferences drawn from them.
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Optically Thick Jet Base and Explanation of Edge Brightening in Active Galactic Nucleus Jets
The Astrophysical JournalThe jet cores in active galactic nuclei (AGNs) are resolved and found to harbor an edge-brightened structure where the jet base appears extended at the sides compared to its propagation axis. This peculiar phenomenon invites various explanations. We show
Mukesh Kumar Vyas, Asaf Pe’er
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PHYSICS OF NONDISSIPATIVE ULTRARELATIVISTIC PHOTOSPHERES [PDF]
International Journal of Modern Physics D, 2014 Recent observations, especially by the Fermi satellite, point out the importance of the thermal component in GRB spectra. This fact revives strong interest in photospheric emission from relativistic outflows. Early studies already suggested that the observed spectrum of photospheric emission from relativistically moving objects differs in shape from ...
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Dynamics of the solar photosphere with IBIS
, 2006 Context.We investigate the quiet solar photosphere with the new Interferometric BI-dimensional Spectrometer (IBIS), recently installed at the Dunn Solar Telescope of the National Solar Observatory, Sacramento Peak, NM.Aims.
G. Cauzzi, K. Janssen
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Optically Thick Outflow Driven by Supercritical Accretion May Explain Little Red Dots
The Astrophysical Journal LettersRecent JWST observations have revealed a population of compact, optically red sources known as Little Red Dots (LRDs). A popular interpretation is that LRDs host massive black holes embedded in dense gaseous envelopes, yet the physical origin of such ...
Jun-Rong Liu, Hua Feng, Luis C. Ho
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On Photospheric Flows and Chromospheric Corks
, 1994 Proper motions of granules are measured by local correlation tracking on a 4.5 h image sequence obtained with the Swedish Vacuum Tower Telescope at La Palma. A 2 arcsec spatial low-pass filter is applied to obtain meso-scale flow patterns. We find that their characteristic lifetime (1/e value) has a lower limit of five to six hours.
Brandt, P.N. +3 more
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Multiwavelength Emission of Gamma-Ray Burst Prompt Phase. II. Spectral Polarimetry
The Astrophysical JournalPolarization spectra were predicted within the photosphere model. To seek more clues to distinguish between the models, both the time-resolved and time-integrated polarization spectra from optical band to MeV gamma-rays of the magnetic reconnection model
Jia-Sheng Li, Mi-Xiang Lan
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Observational Evidence of Shallow Origins for the Magnetic Fields of Solar Cycles
Frontiers in Astronomy and Space Sciences, 2018 Observational evidence for the origin of active region magnetic fields has been sought from published information on extended solar cycles, statistical distributions of active regions and ephemeral regions, helioseismology results, positional ...
Sara F. Martin
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The Astrophysical JournalThe time-integrated polarization degree (PD) in the prompt optical band of a gamma-ray burst (GRB) was predicted to be less than 20%, while the time-resolved one can reach as high as 75% in the photosphere model.
Jia-Sheng Li +2 more
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