Results 21 to 30 of about 22,853 (217)
Reionizing Islands with Inhomogeneous Recombinations
Research in Astronomy and Astrophysics, 2023 Abstract Observations are beginning to constrain the history of the epoch of reionization (EoR). Modeling the reionization process is indispensable to interpret the observations, to infer the properties of ionizing sources, and to probe the various astrophysical processes from the observational data.
Runyu 润玉 Zhu 朱 +3 more
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Journal of Geophysical Research: Space Physics, Volume 128, Issue 10, October 2023., 2023 Abstract We analyze the emission of energetic neutral atom (ENA) flux from charge exchange between Jovian magnetospheric ions and the atmospheres of Callisto and Europa. For this purpose, we combine the draped electromagnetic fields from a hybrid plasma model with a particle tracing tool for the energetic ions.
C. Michael Haynes +5 more
wiley +1 more source
Cosmological reionization [PDF]
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2000 In popular cosmological scenarios, some time beyond a redshift of 10, stars within protogalaxies created the first heavy elements; these systems, together perhaps with an early population of quasars, generated the ultraviolet radiation and mechanical energy that reheated and reionized the cosmos.
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Polarity Asymmetries in Rocket‐Triggered Lightning
Geophysical Research Letters, Volume 50, Issue 17, 16 September 2023., 2023 Abstract The dissonant development of positive and negative lightning leaders is a central question in atmospheric electricity. It is also the likely root cause of other reported asymmetries between positive and negative lightning flashes, including the ones regarding: stroke multiplicity, recoil activity, leader velocities, and emission of energetic ...
C. L. da Silva +10 more
wiley +1 more source
Annalen der Physik, Volume 535, Issue 7, July 2023., 2023 Implications for the cosmological model are explored of the assumption that the cosmic microwave background is subject to an SU(2) Yang– Mills theory of scale 10−4 eV rather than U(1) quantum thermodynamics. This concerns zeroth‐order (changes at high redshifts) and first‐order cosmological perturbations (changes at high and low redshifts).
Ralf Hofmann +2 more
wiley +1 more source
A very extended reionization epoch? [PDF]
Monthly Notices of the Royal Astronomical Society, 2005 The recent observations of cross temperature-polarization power spectra of the Cosmic Microwave Background (CMB) made by the WMAP satellite are in better agreement with a high value of the Thomson scattering optical depth \approx 0.17. This value is close to = 0.3, which is taken as the upper limit in the parameter extraction analysis made by the ...
Melchiorri, A. +3 more
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Self-regulated reionization [PDF]
Monthly Notices of the Royal Astronomical Society, 2007 Recently, we have presented the first large-scale radiative transfer simulations of reionization. Here we present new simulations which extend the source halo mass range downward to 10^8M_solar, to capture the full range of halo masses thought to be primarily responsible for reionization by their star formation following atomic hydrogen radiative ...
Iliev, Ilian T. +3 more
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The Astrophysical Journal, 2023 Baryons both increase halo concentration through adiabatic contraction and expel mass through feedback processes. However, it is not well understood how the radiation fields prevalent during the epoch of reionization affect the evolution of concentration
Hanjue Zhu, Nickolay Y. Gnedin
doaj +1 more source
Reionization with Simba: How Much Does Astrophysics Matter in Modeling Cosmic Reionization?
The Astrophysical Journal, 2022 Abstract Traditional large-scale models of reionization usually employ simple deterministic relations between halo mass and luminosity to predict how reionization proceeds. We here examine the impact on modeling reionization of using more detailed models for the ionizing sources as identified within the 100 h −1 Mpc ...
Sultan Hassan +7 more
openaire +3 more sources
Cosmic Reionization Redux [PDF]
The Astrophysical Journal, 2006 Submitted to ApJ.
Gnedin, Nickolay Y., Fan, Xiaohui
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