中文
相关论文

相关论文: Cosmic Reionization After Planck and Before JWST: …

200 篇论文

Investigating how small-scale physical processes shape large-scale astrophysical phenomena is one of the key science themes of the Astro2020 decadal Survey. An example of this interplay is Cosmic Reionization, where ionizing photons from…

Cosmic Microwave Background temperature and polarization anisotropies from Planck have estimated a lower value of the optical depth to reionization ($\tau$) compared to WMAP. A significant period in the reionization history would then fall…

宇宙学与河外天体物理 · 物理学 2020-08-19 Dhiraj Kumar Hazra , Daniela Paoletti , Fabio Finelli , George F. Smoot

We present the first large-scale radiative transfer simulations of cosmic reionization, in a simulation volume of (100/h Mpc)^3, while at the same time capturing the dwarf galaxies which are primarily responsible for reionization. We…

天体物理学 · 物理学 2008-11-26 Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen , Hugh Merz , Paul R. Shapiro , Marcelo A. Alvarez

The intergalactic medium is expected to clump on scales down to $10^4-10^8$ M$_{\odot}$ before the onset of reionization. The impact of these small-scale structures on reionization is poorly understood despite the modern understanding that…

宇宙学与河外天体物理 · 物理学 2021-03-09 Anson D'Aloisio , Matthew McQuinn , Hy Trac , Christopher Cain , Andrei Mesinger

The Epoch of Reionization marks the last major phase transition in the early Universe, during which the majority of neutral hydrogen once filling the intergalactic medium was ionized by the first galaxies. The James Webb Space Telescope is…

星系天体物理 · 物理学 2025-07-01 Cody Carr , Renyue Cen , Sophia Flury , Sally Oey , Stephan McCandliss , Allison Strom

The study of reionization history plays an important role in understanding the evolution of our universe. It is commonly believed that the intergalactic medium (IGM) in our universe are fully ionized today, however the reionizing process…

宇宙学与河外天体物理 · 物理学 2016-03-09 Yang Liu , Hong Li , Si-Yu Li , Yong-Ping Li , Xinmin Zhang

The history of reionization reflects the cumulative injection of ionizing photons by sources and the absorption of ionizing photons by sinks. The latter process is traditionally described in terms of a "clumping factor" which encodes the…

宇宙学与河外天体物理 · 物理学 2024-07-12 Frederick B. Davies , Sarah E. I. Bosman , Steven R. Furlanetto

Observations on the high-redshift galaxies at $z>6$ imply that their ionizing emissivity is unable to fully reionize the Universe at $z\sim 6$. Either a high escape fraction of ionizing photons from these galaxies or a large population of…

宇宙学与河外天体物理 · 物理学 2015-12-02 Jing-Meng Hao , Ye-Fei Yuan , Lei Wang

The reionization epoch concludes when ionizing photons reach every corner of the Universe. Reionization has generally been assumed to be limited primarily by the rate at which galaxies produce ionizing photons, but the recent measurement of…

宇宙学与河外天体物理 · 物理学 2021-09-22 Frederick B. Davies , Sarah E. I. Bosman , Steven R. Furlanetto , George D. Becker , Anson D'Aloisio

We compute the production rate of photons in the ionizing Lyman continua (LyC) of H I (lambda < 912 A), He I (lambda < 504 A), and He II (lambda < 228 A) using recent stellar evolutionary tracks coupled to a grid of non-LTE, line-blanketed…

太阳与恒星天体物理 · 物理学 2015-06-23 Michael W. Topping , J. Michael Shull

The average rate of emission of ionizing radiation per unit volume (or emissivity) in the universe can be calculated as the ratio of the intensity of the ionizing background to the mean free path of ionizing photons. The intensity of the…

天体物理学 · 物理学 2009-11-07 Jordi Miralda-Escude

An appealing approach for studying the reionization history of the Universe is to measure the redshift evolution of the Lyman-alpha fraction, the percentage of Lyman-break selected galaxies that emit appreciably in the Ly-alpha line. This…

宇宙学与河外天体物理 · 物理学 2015-06-17 Jessie Taylor , Adam Lidz

Quantifying the physical conditions that allow radiation emitted shortward of the hydrogen ionization edge at 911.7 {\AA} to escape the first collapsed objects and ultimately reionize the universe is a compelling problem for astrophysics.…

Recent suggestions of a "photon underproduction crisis" (Kollmeier \etal\ 2014) have generated concern over the intensity and spectrum of ionizing photons in the metagalactic ultraviolet background (UVB). The balance of hydrogen…

宇宙学与河外天体物理 · 物理学 2015-09-23 J. Michael Shull , Joshua Moloney , Charles W. Danforth , Evan M. Tilton

The Lyman continuum (LyC) flux escaping from high-z galaxies into the IGM is a fundamental quantity to understand the physical processes involved in the reionization epoch. We have investigated a sample of star-forming galaxies at z~3.3 in…

We present an updated model of the cosmic ionizing background from the UV to the X-rays. Relative to our previous model (Faucher-Giguere et al. 2009), the new model provides a better match to a large number of up-to-date empirical…

宇宙学与河外天体物理 · 物理学 2020-02-05 C. -A. Faucher-Giguere

The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…

天体物理学 · 物理学 2015-05-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

We present a detailed calculation of the propagation of AGN-like ionizing radiation through the intergalactic space. We model the ionization state of absorbing clouds, and show that the universe will be more opaque above $4\,$Ryd than…

天体物理学 · 物理学 2009-10-28 Francesco Haardt , Piero Madau

We show that numerical simulations of reionization that resolve the Lyman Limit systems (and, thus, correctly count absorptions of ionizing photons) have converged to about 10% level for 5<z<6.2 and are in reasonable agreement (within 10%)…

天体物理学 · 物理学 2010-11-11 Nickolay Y. Gnedin , Xiaohui Fan

Star-forming galaxies in the early universe provide us with perhaps the most natural way of explaining the reionization of the universe. Current observational results are sufficiently comprehensive, as to allow us to approximately calculate…

星系天体物理 · 物理学 2016-01-27 Rychard J. Bouwens