Results 1 to 10 of about 830 (187)

The Impact of Patchy Reionization on Ultrafaint Dwarf Galaxies

The Astrophysical Journal, 2023
We investigate how patchy reionization affects the star formation history (SFH) and stellar metallicity of ultrafaint dwarf galaxies (UFDs). Patchy reionization refers to varying ultraviolet background strengths depending on a galaxy’s environment ...
Jaeeun Kim, Myoungwon Jeon, Yumi Choi, Hannah Richstein, Elena Sacchi, Nitya Kallivayalil   +5 more
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Bridging the Gap between Cosmic Dawn and Reionization Favors Models Dominated by Faint Galaxies

The Astrophysical Journal, 2023
It has been claimed that traditional models struggle to explain the tentative detection of the 21 cm absorption trough centered at z ∼ 17 measured by the EDGES collaboration. On the other hand, it has been shown that the EDGES results are consistent with
Ankita Bera, Sultan Hassan, Aaron Smith, Renyue Cen, Enrico Garaldi, Rahul Kannan, Mark Vogelsberger   +6 more
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Constraints on the Epoch of Reionization with Roman Space Telescope and the Void Probability Function of Lyα Emitters

The Astrophysical Journal, 2023
We use large simulations of Ly α emitters with different fractions of ionized intergalactic medium to quantify the clustering of Ly α emitters as measured by the void probability function (VPF), and how it evolves under different ionization scenarios. We
Lucia A. Perez, Sangeeta Malhotra, James E. Rhoads, Isak G. B. Wold   +3 more
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Simulating the Cosmic Dawn With Enzo

Frontiers in Astronomy and Space Sciences, 2018
We review two decades of progress using the Enzo hydrodynamic cosmology code to simulate the Cosmic Dawn, a period of roughly 1 billion years beginning with the formation of the first stars in the universe, and ending with cosmic reionization.
Michael L. Norman, Michael L. Norman, Britton D. Smith, Britton D. Smith, James Bordner, James Bordner   +5 more
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Cosmic Reionization on Computers: Baryonic Effects on Halo Concentrations during the Epoch of Reionization

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
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The Epoch of Reionization in Warm Dark Matter Scenarios

Universe, 2021
In this paper we investigate how the Reionization process is affected by early galaxy formation in different cosmological scenarios. We use a semi-analytic model with suppressed initial power spectra to obtain the UV Luminosity Function in thermal Warm ...
Massimiliano Romanello, Nicola Menci, Marco Castellano   +2 more
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Crossing the Rubicon of Reionization with z ∼ 5 QSOs

The Astrophysical Journal, 2023
One of the key open questions in cosmology is the nature of sources that completed cosmological hydrogen reionization at z ∼ 5.2. High- z primeval galaxies have been long considered the main drivers of reionization, with a minor role played by high- z ...
Andrea Grazian, Konstantina Boutsia, Emanuele Giallongo, Stefano Cristiani, Fabio Fontanot, Manuela Bischetti, Angela Bongiorno, Giorgio Calderone, Guido Cupani, Valentina D’Odorico, Chiara Feruglio, Fabrizio Fiore, Francesco Guarneri, Matteo Porru, Ivano Saccheo   +14 more
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Lyα visibility from z = 4.5 to 11 in the UDS field: Evidence for a high neutral hydrogen fraction and small ionized bubbles at z ∼ 7

Astronomy & Astrophysics
The resonant scattering nature of Lyα photons interacting with neutral hydrogen makes Lyα emitters (LAEs) robust tracers of the intergalactic neutral hydrogen fraction, and thus sensitive probes of cosmic reionization.
Napolitano L., Pentericci L., Dickinson M., Arrabal Haro P., Taylor A. J., Calabrò A., Bhagwat A., Santini P., Arevalo-Gonzalez F., Begley R., Castellano M., Ciardi B., Donnan C. T., Dottorini D., Dunlop J. S., Finkelstein S. L., Fontana A., Giavalisco M., Hirschmann M., Jung I., Koekemoer A. M., Kokorev V., Llerena M., Lucas R. A., Mascia S., Merlin E., Pérez-González P. G., Stanton T. M., Tripodi R., Wang X., Weiner B. J.   +30 more
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Statistical Detection of the He ii Transverse Proximity Effect: Evidence for Sustained Quasar Activity for >25 Million Years

Frontiers in Astronomy and Space Sciences, 2017
The reionization of helium at z ~ 3 is the final phase transition of the intergalactic medium and supposed to be driven purely by quasars. The He ii transverse proximity effect—enhanced He ii transmission in a background sightline caused by the ionizing ...
Tobias M. Schmidt, Tobias M. Schmidt, Gabor Worseck, Joseph F. Hennawi, Joseph F. Hennawi, J. Xavier Prochaska, Neil H. M. Crighton, Zarija Lukić, Jose Oñorbe   +8 more
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Detecting the signature of helium reionization through 3HeII 3.46 cm line-intensity mapping

Astronomy & Astrophysics
Context. Helium reionization is the most recent phase change of the intergalactic medium, yet its timing and main drivers remain uncertain. Among the probes to trace to trace how it unfolds, the 3.46 cm hyperfine line of singly ionized helium has opened ...
Spina Benedetta, Porciani Cristiano, Bosman Sarah E. I., Davies Frederick B., Garaldi Enrico, Keenan Ryan P., Schimd Carlo   +6 more
doaj   +1 more source