Sizing up lyα and lyman break galaxies

Sangeeta Malhotra, James E. Rhoads, Steven L. Finkelstein, Nimish Hathi, Kim Nilsson, Emily McLinden, Norbert Pirzkal

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

We measure the sizes for a sample of 174 Lyα-selected galaxies with broadband imaging with the Hubble Space Telescope. Over the redshift range 2.25 < z < 6, Lyα-selected galaxies have a characteristic, constant, small size in rest-frame ultraviolet (UV) light. Coupled with a characteristic star formation intensity (i.e., UV luminosity per unit area), this can explain their non-evolving ultraviolet continuum luminosity function. This is in contrast to Lyman break galaxies (LBGs) over the same redshift range, which have been previously shown to increase in linear size as H(z)-1. The compact physical size seems to be a critical determining factor in whether a galaxy will show Lyα emission or not. The L * of LBGs and its evolution with redshift can be derived from a simple model where the star formation intensity has an upper limit set by feedback processes, independent of redshift. The increase in L * of LBGs is mainly driven by the increase in linear size over redshifts for z = 2-7. Since Lyα galaxies do not grow in linear size, they do not show an increase in L *.

Original languageEnglish (US)
Article numberL36
JournalAstrophysical Journal Letters
Volume750
Issue number2
DOIs
StatePublished - May 10 2012

Fingerprint

sizing
galaxies
star formation
luminosity
Hubble Space Telescope
ultraviolet radiation
continuums
broadband

Keywords

  • galaxies: high-redshift

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Malhotra, S., Rhoads, J. E., Finkelstein, S. L., Hathi, N., Nilsson, K., McLinden, E., & Pirzkal, N. (2012). Sizing up lyα and lyman break galaxies. Astrophysical Journal Letters, 750(2), [L36]. https://doi.org/10.1088/2041-8205/750/2/L36

Sizing up lyα and lyman break galaxies. / Malhotra, Sangeeta; Rhoads, James E.; Finkelstein, Steven L.; Hathi, Nimish; Nilsson, Kim; McLinden, Emily; Pirzkal, Norbert.

In: Astrophysical Journal Letters, Vol. 750, No. 2, L36, 10.05.2012.

Research output: Contribution to journalArticle

Malhotra, S, Rhoads, JE, Finkelstein, SL, Hathi, N, Nilsson, K, McLinden, E & Pirzkal, N 2012, 'Sizing up lyα and lyman break galaxies', Astrophysical Journal Letters, vol. 750, no. 2, L36. https://doi.org/10.1088/2041-8205/750/2/L36
Malhotra S, Rhoads JE, Finkelstein SL, Hathi N, Nilsson K, McLinden E et al. Sizing up lyα and lyman break galaxies. Astrophysical Journal Letters. 2012 May 10;750(2). L36. https://doi.org/10.1088/2041-8205/750/2/L36
Malhotra, Sangeeta ; Rhoads, James E. ; Finkelstein, Steven L. ; Hathi, Nimish ; Nilsson, Kim ; McLinden, Emily ; Pirzkal, Norbert. / Sizing up lyα and lyman break galaxies. In: Astrophysical Journal Letters. 2012 ; Vol. 750, No. 2.
@article{a5242620073b47bdae75852345f54da8,
title = "Sizing up lyα and lyman break galaxies",
abstract = "We measure the sizes for a sample of 174 Lyα-selected galaxies with broadband imaging with the Hubble Space Telescope. Over the redshift range 2.25 < z < 6, Lyα-selected galaxies have a characteristic, constant, small size in rest-frame ultraviolet (UV) light. Coupled with a characteristic star formation intensity (i.e., UV luminosity per unit area), this can explain their non-evolving ultraviolet continuum luminosity function. This is in contrast to Lyman break galaxies (LBGs) over the same redshift range, which have been previously shown to increase in linear size as H(z)-1. The compact physical size seems to be a critical determining factor in whether a galaxy will show Lyα emission or not. The L * of LBGs and its evolution with redshift can be derived from a simple model where the star formation intensity has an upper limit set by feedback processes, independent of redshift. The increase in L * of LBGs is mainly driven by the increase in linear size over redshifts for z = 2-7. Since Lyα galaxies do not grow in linear size, they do not show an increase in L *.",
keywords = "galaxies: high-redshift",
author = "Sangeeta Malhotra and Rhoads, {James E.} and Finkelstein, {Steven L.} and Nimish Hathi and Kim Nilsson and Emily McLinden and Norbert Pirzkal",
year = "2012",
month = "5",
day = "10",
doi = "10.1088/2041-8205/750/2/L36",
language = "English (US)",
volume = "750",
journal = "Astrophysical Journal Letters",
issn = "2041-8205",
publisher = "IOP Publishing Ltd.",
number = "2",

}

TY - JOUR

T1 - Sizing up lyα and lyman break galaxies

AU - Malhotra, Sangeeta

AU - Rhoads, James E.

AU - Finkelstein, Steven L.

AU - Hathi, Nimish

AU - Nilsson, Kim

AU - McLinden, Emily

AU - Pirzkal, Norbert

PY - 2012/5/10

Y1 - 2012/5/10

N2 - We measure the sizes for a sample of 174 Lyα-selected galaxies with broadband imaging with the Hubble Space Telescope. Over the redshift range 2.25 < z < 6, Lyα-selected galaxies have a characteristic, constant, small size in rest-frame ultraviolet (UV) light. Coupled with a characteristic star formation intensity (i.e., UV luminosity per unit area), this can explain their non-evolving ultraviolet continuum luminosity function. This is in contrast to Lyman break galaxies (LBGs) over the same redshift range, which have been previously shown to increase in linear size as H(z)-1. The compact physical size seems to be a critical determining factor in whether a galaxy will show Lyα emission or not. The L * of LBGs and its evolution with redshift can be derived from a simple model where the star formation intensity has an upper limit set by feedback processes, independent of redshift. The increase in L * of LBGs is mainly driven by the increase in linear size over redshifts for z = 2-7. Since Lyα galaxies do not grow in linear size, they do not show an increase in L *.

AB - We measure the sizes for a sample of 174 Lyα-selected galaxies with broadband imaging with the Hubble Space Telescope. Over the redshift range 2.25 < z < 6, Lyα-selected galaxies have a characteristic, constant, small size in rest-frame ultraviolet (UV) light. Coupled with a characteristic star formation intensity (i.e., UV luminosity per unit area), this can explain their non-evolving ultraviolet continuum luminosity function. This is in contrast to Lyman break galaxies (LBGs) over the same redshift range, which have been previously shown to increase in linear size as H(z)-1. The compact physical size seems to be a critical determining factor in whether a galaxy will show Lyα emission or not. The L * of LBGs and its evolution with redshift can be derived from a simple model where the star formation intensity has an upper limit set by feedback processes, independent of redshift. The increase in L * of LBGs is mainly driven by the increase in linear size over redshifts for z = 2-7. Since Lyα galaxies do not grow in linear size, they do not show an increase in L *.

KW - galaxies: high-redshift

UR - http://www.scopus.com/inward/record.url?scp=84860327933&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84860327933&partnerID=8YFLogxK

U2 - 10.1088/2041-8205/750/2/L36

DO - 10.1088/2041-8205/750/2/L36

M3 - Article

AN - SCOPUS:84860327933

VL - 750

JO - Astrophysical Journal Letters

JF - Astrophysical Journal Letters

SN - 2041-8205

IS - 2

M1 - L36

ER -