Non-parametric analysis of the rest-frame UV sizes and morphological disturbance amongst L* galaxies at 4 <z <8

E. Curtis-Lake, R. J. McLure, J. S. Dunlop, A. B. Rogers, T. Targett, A. Dekel, R. S. Ellis, S. M. Faber, H. C. Ferguson, N. A. Grogin, D. D. Kocevski, A. M. Koekemoer, K. Lai, E. Mármol-Queraltó, Brant E Robertson

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

We present the results of a study investigating the sizes and morphologies of redshift 4 <z <8 galaxies in the CANDELS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) GOODS-S (Great Observatories Origins Deep Survey southern field), HUDF (Hubble Ultra-Deep Field) and HUDF parallel fields. Based on non-parametric measurements and incorporating a careful treatment of measurement biases, we quantify the typical size of galaxies at each redshift as the peak of the lognormal size distribution, rather than the arithmetic mean size. Parametrizing the evolution of galaxy half-light radius as r50 α(1 + z)n, we find n = -0.20 ± 0.26 at bright UV-luminosities (0.3L*(z=3) <L <L*) and n = -0.47 ± 0.62 at faint luminosities (0.12L* <L <0.3L*). Furthermore, simulations based on artificially redshifting our z ~ 4 galaxy sample show that we cannot reject the null hypothesis of no size evolution.We show that this result is caused by a combination of the size-dependent completeness of high-redshift galaxy samples and the underestimation of the sizes of the largest galaxies at a given epoch. To explore the evolution of galaxy morphology we first compare asymmetry measurements to those from a large sample of simulated single Sérsic profiles, in order to robustly categorize galaxies as either 'smooth' or 'disturbed'. Comparing the disturbed fraction amongst bright (M1500 ≤-20) galaxies at each redshift to that obtained by artificially redshifting our z ~ 4 galaxy sample, while carefully matching the size and UV-luminosity distributions, we find no clear evidence for evolution in galaxy morphology over the redshift interval 4 <z <8. Therefore, based on our results, a bright (M1500 ≤ -20) galaxy at z ~ 6 is no more likely to be measured as 'disturbed' than a comparable galaxy at z ~ 4, given the current observational constraints.

Original languageEnglish (US)
Pages (from-to)440-464
Number of pages25
JournalMonthly Notices of the Royal Astronomical Society
Volume457
Issue number1
DOIs
StatePublished - Jan 11 2016

Fingerprint

disturbances
galaxies
disturbance
luminosity
analysis
asymmetry
near infrared
observatory
null hypothesis
completeness
simulation
observatories
assembly
time measurement
intervals
radii

Keywords

  • Galaxies: evolution
  • Galaxies: high-redshift
  • Galaxies: star formation
  • Galaxies: structure

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Non-parametric analysis of the rest-frame UV sizes and morphological disturbance amongst L* galaxies at 4 <z <8. / Curtis-Lake, E.; McLure, R. J.; Dunlop, J. S.; Rogers, A. B.; Targett, T.; Dekel, A.; Ellis, R. S.; Faber, S. M.; Ferguson, H. C.; Grogin, N. A.; Kocevski, D. D.; Koekemoer, A. M.; Lai, K.; Mármol-Queraltó, E.; Robertson, Brant E.

In: Monthly Notices of the Royal Astronomical Society, Vol. 457, No. 1, 11.01.2016, p. 440-464.

Research output: Contribution to journalArticle

Curtis-Lake, E, McLure, RJ, Dunlop, JS, Rogers, AB, Targett, T, Dekel, A, Ellis, RS, Faber, SM, Ferguson, HC, Grogin, NA, Kocevski, DD, Koekemoer, AM, Lai, K, Mármol-Queraltó, E & Robertson, BE 2016, 'Non-parametric analysis of the rest-frame UV sizes and morphological disturbance amongst L* galaxies at 4 <z <8', Monthly Notices of the Royal Astronomical Society, vol. 457, no. 1, pp. 440-464. https://doi.org/10.1093/mnras/stv3017
Curtis-Lake, E. ; McLure, R. J. ; Dunlop, J. S. ; Rogers, A. B. ; Targett, T. ; Dekel, A. ; Ellis, R. S. ; Faber, S. M. ; Ferguson, H. C. ; Grogin, N. A. ; Kocevski, D. D. ; Koekemoer, A. M. ; Lai, K. ; Mármol-Queraltó, E. ; Robertson, Brant E. / Non-parametric analysis of the rest-frame UV sizes and morphological disturbance amongst L* galaxies at 4 <z <8. In: Monthly Notices of the Royal Astronomical Society. 2016 ; Vol. 457, No. 1. pp. 440-464.
@article{7e1aad85f4dd4753b51200181dca78a4,
title = "Non-parametric analysis of the rest-frame UV sizes and morphological disturbance amongst L* galaxies at 4 <z <8",
abstract = "We present the results of a study investigating the sizes and morphologies of redshift 4 n, we find n = -0.20 ± 0.26 at bright UV-luminosities (0.3L*(z=3) <L <L*) and n = -0.47 ± 0.62 at faint luminosities (0.12L* <L <0.3L*). Furthermore, simulations based on artificially redshifting our z ~ 4 galaxy sample show that we cannot reject the null hypothesis of no size evolution.We show that this result is caused by a combination of the size-dependent completeness of high-redshift galaxy samples and the underestimation of the sizes of the largest galaxies at a given epoch. To explore the evolution of galaxy morphology we first compare asymmetry measurements to those from a large sample of simulated single S{\'e}rsic profiles, in order to robustly categorize galaxies as either 'smooth' or 'disturbed'. Comparing the disturbed fraction amongst bright (M1500 ≤-20) galaxies at each redshift to that obtained by artificially redshifting our z ~ 4 galaxy sample, while carefully matching the size and UV-luminosity distributions, we find no clear evidence for evolution in galaxy morphology over the redshift interval 4 1500 ≤ -20) galaxy at z ~ 6 is no more likely to be measured as 'disturbed' than a comparable galaxy at z ~ 4, given the current observational constraints.",
keywords = "Galaxies: evolution, Galaxies: high-redshift, Galaxies: star formation, Galaxies: structure",
author = "E. Curtis-Lake and McLure, {R. J.} and Dunlop, {J. S.} and Rogers, {A. B.} and T. Targett and A. Dekel and Ellis, {R. S.} and Faber, {S. M.} and Ferguson, {H. C.} and Grogin, {N. A.} and Kocevski, {D. D.} and Koekemoer, {A. M.} and K. Lai and E. M{\'a}rmol-Queralt{\'o} and Robertson, {Brant E}",
year = "2016",
month = "1",
day = "11",
doi = "10.1093/mnras/stv3017",
language = "English (US)",
volume = "457",
pages = "440--464",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "1",

}

TY - JOUR

T1 - Non-parametric analysis of the rest-frame UV sizes and morphological disturbance amongst L* galaxies at 4 <z <8

AU - Curtis-Lake, E.

AU - McLure, R. J.

AU - Dunlop, J. S.

AU - Rogers, A. B.

AU - Targett, T.

AU - Dekel, A.

AU - Ellis, R. S.

AU - Faber, S. M.

AU - Ferguson, H. C.

AU - Grogin, N. A.

AU - Kocevski, D. D.

AU - Koekemoer, A. M.

AU - Lai, K.

AU - Mármol-Queraltó, E.

AU - Robertson, Brant E

PY - 2016/1/11

Y1 - 2016/1/11

N2 - We present the results of a study investigating the sizes and morphologies of redshift 4 n, we find n = -0.20 ± 0.26 at bright UV-luminosities (0.3L*(z=3) <L <L*) and n = -0.47 ± 0.62 at faint luminosities (0.12L* <L <0.3L*). Furthermore, simulations based on artificially redshifting our z ~ 4 galaxy sample show that we cannot reject the null hypothesis of no size evolution.We show that this result is caused by a combination of the size-dependent completeness of high-redshift galaxy samples and the underestimation of the sizes of the largest galaxies at a given epoch. To explore the evolution of galaxy morphology we first compare asymmetry measurements to those from a large sample of simulated single Sérsic profiles, in order to robustly categorize galaxies as either 'smooth' or 'disturbed'. Comparing the disturbed fraction amongst bright (M1500 ≤-20) galaxies at each redshift to that obtained by artificially redshifting our z ~ 4 galaxy sample, while carefully matching the size and UV-luminosity distributions, we find no clear evidence for evolution in galaxy morphology over the redshift interval 4 1500 ≤ -20) galaxy at z ~ 6 is no more likely to be measured as 'disturbed' than a comparable galaxy at z ~ 4, given the current observational constraints.

AB - We present the results of a study investigating the sizes and morphologies of redshift 4 n, we find n = -0.20 ± 0.26 at bright UV-luminosities (0.3L*(z=3) <L <L*) and n = -0.47 ± 0.62 at faint luminosities (0.12L* <L <0.3L*). Furthermore, simulations based on artificially redshifting our z ~ 4 galaxy sample show that we cannot reject the null hypothesis of no size evolution.We show that this result is caused by a combination of the size-dependent completeness of high-redshift galaxy samples and the underestimation of the sizes of the largest galaxies at a given epoch. To explore the evolution of galaxy morphology we first compare asymmetry measurements to those from a large sample of simulated single Sérsic profiles, in order to robustly categorize galaxies as either 'smooth' or 'disturbed'. Comparing the disturbed fraction amongst bright (M1500 ≤-20) galaxies at each redshift to that obtained by artificially redshifting our z ~ 4 galaxy sample, while carefully matching the size and UV-luminosity distributions, we find no clear evidence for evolution in galaxy morphology over the redshift interval 4 1500 ≤ -20) galaxy at z ~ 6 is no more likely to be measured as 'disturbed' than a comparable galaxy at z ~ 4, given the current observational constraints.

KW - Galaxies: evolution

KW - Galaxies: high-redshift

KW - Galaxies: star formation

KW - Galaxies: structure

UR - http://www.scopus.com/inward/record.url?scp=84961574758&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84961574758&partnerID=8YFLogxK

U2 - 10.1093/mnras/stv3017

DO - 10.1093/mnras/stv3017

M3 - Article

AN - SCOPUS:84961574758

VL - 457

SP - 440

EP - 464

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 1

ER -