Sökning: "Epoch of Reionization"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Epoch of Reionization.

  1. 1. Galaxies in the epoch of reionization : Investigating the high-redshift galaxy population through simulations and observations

    Författare :Christian Binggeli; Erik Zackrisson; Sofia Ramstedt; Martin Sahlén; Stephen Wilkins; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; galaxies: high-redshift; galaxies: ISM; galaxies: evolution; reionization; Lyman continuum; Astronomy; Astronomi;

    Sammanfattning : The cosmic reionization is the last major gas phase transition in cosmic history, yet it remains poorly understood. Current constraints indicate that early star-forming galaxies drove the reionization process through producing and releasing large numbers of ionizing photons into the intergalactic medium. LÄS MER

  3. 2. Simulations of Cosmic Reionization : Shapes & Sizes of H II regions around Galaxies and Quasars

    Författare :Martina M. Friedrich; Garrelt Mellema; Jonathan Pritchard; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi;

    Sammanfattning : After the era of recombination, roughly 360 000 years after the big bang (redshift 1100), the universe was neutral, continued to expand and eventually the first gravitationally collapsed structures capable of forming stars, formed. Observations show that approximately 1 billion years later (redshift 6), the Universe had become highly ionized. LÄS MER

  4. 3. Neutral gas properties of high-redshift analog galaxies : 21cm observations of Lyα and LyC-emitting galaxies

    Författare :Alexandra Le Reste; Matthew J. Hayes; John Cannon; Rychard Bouwens; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Galaxies; Lyman alpha; Lyman Continuum; 21cm line; Interacting galaxies; Epoch of Reionization; Astronomy; astronomi;

    Sammanfattning : Neutral hydrogen (HI) is the most abundant baryonic element and a crucial component of galaxies. In the early universe, the interaction between neutral gas and the light produced by galaxies is thought to have given rise to cosmological reionization. LÄS MER

  5. 4. Using Lyα to illuminate the circumgalactic medium and the Epoch of Reionization : Lessons from low redshift

    Författare :Axel Runnholm; Matthew J. Hayes; Ross McLure; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lyman alpha galaxies; Starburst galaxies; Galaxy evolution; Epoch of Reionization; Circumgalactic medium; Astronomy; astronomi;

    Sammanfattning : The field of extragalactic astronomy is progressing rapidly but there is still much to understand and many questions that remain open. During recent years the Lyα emission line has come to the fore as a potentially very powerful astrophysical tool and is now routinely used to find galaxies at the very highest redshifts. LÄS MER

  7. 5. Tomographic studies of the 21-cm signal during reionization : Going beyond the power spectrum

    Författare :Sambit K. Giri; Garrelt Mellema; Benoît Semelin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; reionization; non-gaussianity; first stars; image processing; Astronomy; astronomi;

    Sammanfattning : The formation of the first luminous sources in the Universe, such as the first generation of stars and accreting black holes, led to the ionization of hydrogen gas present in the intergalactic medium (IGM). This period in which the Universe transitioned from a cold and neutral state to a predominantly hot and ionized state is known as the Epoch of Reionization (EoR). LÄS MER