---
OA_type: closed access
_id: '18725'
abstract:
- lang: eng
  text: In hierarchical models of structure formation, an early cosmic UV background(UVB)
    is produced by the small (T vir ≲ 104K) halos that collapse before cosmological
    reionization. If the sources in the first collapsed halos are stars, then their
    UV flux below 13.6 eV photo-dissociates the molecular hydrogen H2 in subsequently
    collapsing halos and causes a pause in the cosmic star-formation history. The
    buildup of the UVB, and reionization is delayed until larger halos (T vir ≳ 104K)
    collapse. In contrast, if the small halos host mini-quasars with hard spectra
    extending to∼1keV, then their X-rays balance the effects of the UVB, the negative
    feedback does not occur, and reionization can be caused early on by the small
    halos.
article_processing_charge: No
article_type: original
author:
- first_name: Zoltán
  full_name: Haiman, Zoltán
  id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
  last_name: Haiman
  orcid: 0000-0003-3633-5403
citation:
  ama: Haiman Z. Radiative feedback from the first objects and the end of the cosmological
    dark age. <i>Astrophysics and Space Science</i>. 1999;269:191-199. doi:<a href="https://doi.org/10.1023/a:1017062512507">10.1023/a:1017062512507</a>
  apa: Haiman, Z. (1999). Radiative feedback from the first objects and the end of
    the cosmological dark age. <i>Astrophysics and Space Science</i>. Springer Nature.
    <a href="https://doi.org/10.1023/a:1017062512507">https://doi.org/10.1023/a:1017062512507</a>
  chicago: Haiman, Zoltán. “Radiative Feedback from the First Objects and the End
    of the Cosmological Dark Age.” <i>Astrophysics and Space Science</i>. Springer
    Nature, 1999. <a href="https://doi.org/10.1023/a:1017062512507">https://doi.org/10.1023/a:1017062512507</a>.
  ieee: Z. Haiman, “Radiative feedback from the first objects and the end of the cosmological
    dark age,” <i>Astrophysics and Space Science</i>, vol. 269. Springer Nature, pp.
    191–199, 1999.
  ista: Haiman Z. 1999. Radiative feedback from the first objects and the end of the
    cosmological dark age. Astrophysics and Space Science. 269, 191–199.
  mla: Haiman, Zoltán. “Radiative Feedback from the First Objects and the End of the
    Cosmological Dark Age.” <i>Astrophysics and Space Science</i>, vol. 269, Springer
    Nature, 1999, pp. 191–99, doi:<a href="https://doi.org/10.1023/a:1017062512507">10.1023/a:1017062512507</a>.
  short: Z. Haiman, Astrophysics and Space Science 269 (1999) 191–199.
date_created: 2025-01-03T12:07:53Z
date_published: 1999-12-01T00:00:00Z
date_updated: 2025-01-03T12:08:38Z
day: '01'
doi: 10.1023/a:1017062512507
extern: '1'
fulldoi: https://doi.org/10.1023/a:1017062512507
intvolume: '       269'
language:
- iso: eng
month: '12'
oa_version: None
page: 191-199
publication: Astrophysics and Space Science
publication_identifier:
  eissn:
  - 1572-946X
  issn:
  - 0004-640X
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Radiative feedback from the first objects and the end of the cosmological dark
  age
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 269
year: '1999'
...