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Related papers: LIMFAST. I. A Semi-Numerical Tool for Line Intensi…

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We have modelled the process of reionization of the IGM by photoionization by galaxies, in order to predict the epoch of reionization. We use a sophisticated semi-analytic model to track the formation of galaxies. Our study represents a…

Astrophysics · Physics 2009-11-11 A. J. Benson , Naoshi Sugiyama , Adi Nusser , C. G. Lacey

We demonstrate the potential of line-intensity mapping to place constraints on the initial mass function (IMF) of Population III stars via measurements of the mean He II 1640A/H$\alpha$ line-intensity ratio. We extend the 21cmFAST code with…

Astrophysics of Galaxies · Physics 2022-08-02 Jasmine Parsons , Lluis Mas-Ribas , Guochao Sun , Tzu-Ching Chang , Michael O. Gonzalez , Richard H. Mebane

We calculate the redshift evolution of the global 21cm signal in the first billion years using a semi-analytic galaxy formation model, DELPHI, that jointly tracks the assembly of dark matter halos and their constituent baryons including the…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 Atrideb Chatterjee , Pratika Dayal , Valentin Mauerhofer

We use cosmological hydrodynamic simulations with stellar feedback from the FIRE project to study the physical nature of Lyman limit systems (LLSs) at z<1. At these low redshifts, LLSs are closely associated with dense gas structures…

Astrophysics of Galaxies · Physics 2017-06-21 Z. Hafen , C. -A. Faucher-Giguere , D. Angles-Alcazar , D. Keres , R. Feldmann , T. K. Chan , E. Quataert , N. Murray , P. F. Hopkins

The 21-cm forest is a promising probe of the Epoch of Reionization. The local state of the intergalactic medium (IGM) is encoded in the spectrum of a background source (radio-loud quasars or gamma ray burst afterglow) by absorption at the…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Benoit Semelin

Intensity mapping of multiple emission lines is emerging as a new branch to astronomy, to probe both properties of ionizing sources and the medium between, in particular the intergalactic medium. For Epoch of Reionization (EoR) studies,…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-03 Caroline Heneka , Asantha Cooray

In a semi-numerical model of reionization, the evolution of ionization fraction is simulated approximately by the ionizing photon to baryon ratio criterion. In this paper we incorporate a semi-analytical model of galaxy formation based on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jie Zhou , Qi Guo , Gaochao Liu , Bin Yue , Yidong Xu , Xuelei Chen

Line intensity mapping (LIM) is a promising tool to efficiently probe the three-dimensional large-scale structure by mapping the aggregate emission of a spectral line from all sources that trace the matter density field. Spectral lines from…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-09 Yun-Ting Cheng , Tzu-Ching Chang , James J. Bock

There are thousands of confirmed detections of star forming galaxies at high redshift (z > 4). These observations rely primarily on the detection of the spectral Lyman Break and the Lyman-alpha emission line. Theoretical modelling of these…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-06 Jaime E. Forero-Romero , Gustavo Yepes , Stefan Gottloeber , Francisco Prada

Redshifted 21cm measurements of the structure of ionised regions that grow during reionization promise to provide a new probe of early galaxy and structure formation. One of the challenges of modelling reionization is to account both for…

Astrophysics of Galaxies · Physics 2015-12-16 Han-Seek Kim , J. Stuart B. Wyithe , Jaehong Park , Gregory B. Poole , C. G. Lacey , C. M. Baugh

Observations of the epoch of reionization give us clues about the nature and evolution of the sources of ionizing photons, or early stars and galaxies. We present a new suite of structure formation and radiative transfer simulations from…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Keri L. Dixon , Ilian T. Iliev , Garrelt Mellema , Kyungjin Ahn , Paul R. Shapiro

We predict the 21-cm global signal and power spectra during the Epoch of Reionisation using the MERAXES semi-analytic galaxy formation and reionisation model, updated to include X-ray heating and thermal evolution of the intergalactic…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-21 Sreedhar Balu , Bradley Greig , Yisheng Qiu , Chris Power , Yuxiang Qin , Simon Mutch , J. Stuart B. Wyithe

We use the latest multi-redshift ($z=6.5-8.7$) upper limits on the 21-cm signal from the Murchison Widefield Array (MWA) to explore astrophysical models which are inconsistent with the data. These upper limits are achieved using 298 h of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Bradley Greig , Cathryn M. Trott , Nichole Barry , Simon J. Mutch , Bart Pindor , Rachel L. Webster , J. Stuart B. Wyithe

We introduce the ASTRID simulation, a large-scale cosmological hydrodynamic simulation in a $250$ Mpc/h box with $2\times 5500^3$ particles. ASTRID contains a large number of high redshift galaxies, which can be compared to future survey…

Astrophysics of Galaxies · Physics 2022-03-24 Simeon Bird , Yueying Ni , Tiziana Di Matteo , Rupert Croft , Yu Feng , Nianyi Chen

Understanding the epoch of reionization and the properties of the first galaxies represents an important goal for modern cosmology. The structure of reionization, and hence the observed power spectrum of redshifted 21cm fluctuations are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Han-Seek Kim , J. Stuart B. Wyithe , Sudhir Raskutti , C. G. Lacey , J. C. Helly

Using high redshift radio sources as background, the 21cm forest observations probe the neutral hydrogen absorption signatures of early structures along the lines of sight. Directly sensitive to the spin temperature, it complements the 21cm…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Yidong Xu , Xuelei Chen , Zuhui Fan , Hy Trac , Renyue Cen

Characterise the large-scale structure in the Universe from present times to the high redshift epoch of reionisation is essential to constraining the cosmology, the history of star formation and reionisation, measuring the gas content of…

Weak gravitational lensing of the 21 cm radiation is expected to be an important cosmological probe for post-reionization physics. We investigate the reconstruction of the matter density perturbations using a quadratic minimum variance…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-10 Priyesh Chakraborty , Anthony R. Pullen

Reionization is thought to be dominated by low mass galaxies, while direct observations of resolved galaxies probe only the most massive, rarest objects. The cross-correlation between fluctuations in the surface brightness of the cumulative…

Astrophysics · Physics 2019-08-19 Stuart Wyithe , Avi Loeb , Brian Schmidt