Cited by 450Galaxies: Formation, Evolution, PhenomenaStellar, planetary, and galactic studiesAstrophysics and Star Formation Studies

THE MAJOR AND MINOR GALAXY MERGER RATES AT z < 1.5

Open access
Lotz, Jennifer M., Jonsson, Patrik, Cox, T. J., Croton, Darren, Primack, Joel R., Somerville, Rachel S., Stewart, Kyle·2011·The Astrophysical Journal

Abstract

Calculating the galaxy merger rate requires both a census of galaxies identified as merger candidates and a cosmologically averaged "observability" timescale 〈 T obs ( z )〉 for identifying galaxy mergers. While many have counted galaxy mergers using a variety of techniques, 〈 T obs ( z )〉 for these techniques have been poorly constrained. We address this problem by calibrating three merger rate estimators with a suite of hydrodynamic merger simulations and three galaxy formation models. We estimate 〈 T obs ( z )〉 for (1) close galaxy pairs with a range of projected separations, (2) the morphology indicator G − M 20 , and (3) the morphology indicator asymmetry A . Then, we apply these timescales to the observed merger fractions at z < 1.5 from the recent literature. When our physically motivated timescales are adopted, the observed galaxy merger rates become largely consistent. The remaining differences between the galaxy merger rates are explained by the differences in the ranges of the mass ratio measured by different techniques and differing parent galaxy selection. The major merger rate per unit comoving volume for samples selected with constant number density evolves much more strongly with redshift (∝(1 + z ) +3.0 ± 1.1 ) than samples selected with constant stellar mass or passively evolving luminosity (∝(1 + z ) +0.1 ± 0.4 ). We calculate the minor merger rate (1:4 < M sat / M primary ≲ 1:10) by subtracting the major merger rate from close pairs from the "total" merger rate determined by G − M 20 . The implied minor merger rate is ∼3 times the major merger rate at z ∼ 0.7 and shows little evolution with redshift.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1088/0004-637x/742/2/103

Cites

120 of 120 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. [110]110. Stewart, K. R. 2009, in ASP Conf. Ser. 419, Galaxy Evolution: Emerging Insights and Future Challenges, ed. S. Jogee, I.

Cited by

Sorted by citations

Authors
Lotz, J. M., Jonsson, P., Cox, T. J., Croton, D., Primack, J. R., Somerville, R. S., & Stewart, K.
Affiliations
  • Space Telescope Science Institute (US)
  • Smithsonian Astrophysical Observatory (US)
  • Carnegie Observatories (US)
  • Swinburne University of Technology (AU)
  • University of California, Santa Cruz (US)
  • Jet Propulsion Laboratory (US)
Corresponding author
Lotz, Jennifer M.
Venue
The Astrophysical Journal
Published
2011-11-14
Volume
742
Issue
2
Pages
103
ISSN
  • 0004-637X (ISSN-L)
  • 1538-4357
OpenAlex
W2104453758
Cited by
450
References
120
Citations by year
2026: 12 · 2025: 31 · 2024: 20 · 2023: 26 · 2022: 26 · 2021: 34 · 2020: 24 · 2019: 30 · 2018: 42 · 2017: 28 · 2016: 31 · 2015: 40 · 2014: 37 · 2013: 32 · 2012: 35
FWCI
18.00
Type
journal article
Language
en
Open access
Locations
  • The Astrophysical Journal (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • Swinburne figshare (Swinburne University of Technology) (submittedVersion)
  • arXiv (Cornell University)
Funders
  • U.S. Department of Energy
  • National Aeronautics and Space Administration
  • W. M. Keck Foundation
  • Johns Hopkins University
  • Australian Government
  • National Energy Research Scientific Computing Center
  • Office of Science
Topics
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Galaxies: Formation, Evolution, Phenomena
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Stellar, planetary, and galactic studies
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astrophysics and Star Formation Studies
Keywords
major mergers, minor mergers, high-redshift galaxies, close galaxy pairs, galaxy morphology, galaxy formation models, redshift evolution, mass ratio

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review