---
_id: '17694'
abstract:
- lang: eng
  text: Constraining the properties of Population III (Pop III) stars will be very
    challenging because they reside in small galaxies at high redshift which will
    be difficult to directly detect. In this paper, we suggest that intensity mapping
    may be a promising method to study Pop III stars. Intensity mapping is a technique
    proposed to measure large-scale fluctuations of galaxy line emission in three
    dimensions without resolving individual sources. This technique is well suited
    for observing many faint galaxies because it can measure their cumulative emission
    even if they cannot be directly detected. We focus on intensity mapping of He
    ii recombination lines. These lines are much stronger in Pop III stars than Pop
    II stars because the harder spectra of Pop III stars are expected to produce many
    He ii ionizing photons. Measuring the He ii 1640 Å intensity mapping signal, along
    with the signals from other lines such as Lyα, Hα, and metal lines, could give
    constraints on the initial mass function (IMF) and star formation rate density
    of Pop III stars as a function of redshift. To demonstrate the feasibility of
    these observations, we estimate the strength of the Pop III He ii 1640 Å intensity
    mapping signal from z = 10–20. We show that at z ≈ 10, the signal could be measured
    accurately by two different hypothetical future instruments, one which cross-correlates
    He ii 1640 Å with CO(1–0) line emission from galaxies and the other with 21 cm
    emission from the intergalactic medium.
article_processing_charge: No
article_type: original
author:
- first_name: Eli
  full_name: Visbal, Eli
  last_name: Visbal
- first_name: Zoltán
  full_name: Haiman, Zoltán
  id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
  last_name: Haiman
- first_name: Greg L.
  full_name: Bryan, Greg L.
  last_name: Bryan
citation:
  ama: Visbal E, Haiman Z, Bryan GL. Looking for Population III stars with He ii line
    intensity mapping. <i>Monthly Notices of the Royal Astronomical Society</i>. 2015;450(3):2506-2513.
    doi:<a href="https://doi.org/10.1093/mnras/stv785">10.1093/mnras/stv785</a>
  apa: Visbal, E., Haiman, Z., &#38; Bryan, G. L. (2015). Looking for Population III
    stars with He ii line intensity mapping. <i>Monthly Notices of the Royal Astronomical
    Society</i>. Oxford University Press. <a href="https://doi.org/10.1093/mnras/stv785">https://doi.org/10.1093/mnras/stv785</a>
  chicago: Visbal, Eli, Zoltán Haiman, and Greg L. Bryan. “Looking for Population
    III Stars with He Ii Line Intensity Mapping.” <i>Monthly Notices of the Royal
    Astronomical Society</i>. Oxford University Press, 2015. <a href="https://doi.org/10.1093/mnras/stv785">https://doi.org/10.1093/mnras/stv785</a>.
  ieee: E. Visbal, Z. Haiman, and G. L. Bryan, “Looking for Population III stars with
    He ii line intensity mapping,” <i>Monthly Notices of the Royal Astronomical Society</i>,
    vol. 450, no. 3. Oxford University Press, pp. 2506–2513, 2015.
  ista: Visbal E, Haiman Z, Bryan GL. 2015. Looking for Population III stars with
    He ii line intensity mapping. Monthly Notices of the Royal Astronomical Society.
    450(3), 2506–2513.
  mla: Visbal, Eli, et al. “Looking for Population III Stars with He Ii Line Intensity
    Mapping.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 450,
    no. 3, Oxford University Press, 2015, pp. 2506–13, doi:<a href="https://doi.org/10.1093/mnras/stv785">10.1093/mnras/stv785</a>.
  short: E. Visbal, Z. Haiman, G.L. Bryan, Monthly Notices of the Royal Astronomical
    Society 450 (2015) 2506–2513.
date_created: 2024-09-06T08:40:33Z
date_published: 2015-05-06T00:00:00Z
date_updated: 2024-09-25T10:05:24Z
day: '06'
doi: 10.1093/mnras/stv785
extern: '1'
intvolume: '       450'
issue: '3'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1093/mnras/stv785
month: '05'
oa: 1
oa_version: Published Version
page: 2506-2513
publication: Monthly Notices of the Royal Astronomical Society
publication_identifier:
  issn:
  - 0035-8711
  - 1365-2966
publication_status: published
publisher: Oxford University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Looking for Population III stars with He ii line intensity mapping
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 450
year: '2015'
...