RT Journal Article
T1 Role of galaxy mergers in cosmic star formation history
A1 Shi, Yong
A1 Rieke, George
A1 Lotz, Jennifer
A1 Pérez González, Pablo Guillermo
AB We present a morphology study of intermediate-redshift (0.2 < z < 1.2) luminous infrared galaxies (LIRGs) and general field galaxies in the GOODS fields using a revised asymmetry measurement method optimized for deep fields. By taking careful account of the importance of the underlying sky-background structures, our new method does not suffer from systematic bias and offers small uncertainties. By redshifting local LIRGs and low-redshift GOODS galaxies to different higher redshifts, we have found that the redshift dependence of the galaxy asymmetry due to surface-brightness dimming is a function of the asymmetry itself, with larger corrections for more asymmetric objects. By applying redshift-, infrared (IR)-luminosity- and optical-brightness-dependent asymmetry corrections, we have found that intermediate-redshift LIRGs generally show highly asymmetric morphologies, with implied merger fractions ~50% up to z = 1.2, although they are slightly more symmetric than local LIRGs. For general field galaxies, we find an almost constant relatively high merger fraction (20%-30%). The B-band luminosity functions (LFs) of galaxy mergers are derived at different redshifts up to z = 1.2 and confirm the weak evolution of the merger fraction after breaking the luminosity-density degeneracy. The IR LFs of galaxy mergers are also derived, indicating a larger merger fraction at higher IR luminosity. The integral of the merger IR LFs indicates a dramatic evolution of the merger-induced IR energy density [(1 + z)^~(5-6)], and that galaxy mergers start to dominate the cosmic IR energy density at z greater than or ~ 1.
PB American Astronomical Society
SN 0004-637X
YR 2009
FD 2009-06-01
LK https://hdl.handle.net/20.500.14352/45118
UL https://hdl.handle.net/20.500.14352/45118
LA eng
NO © 2009 The American Astronomical Society. All rights reserved. We thank the anonymous referee for detailed comments. Support for this work was provided by NASA through contract 1255094 issued by JPL/California Institute of Technology. J.M.L. acknowledges support from Leo Goldberg Fellowship sponsored by the National Optical Astronomy Observatory. P.G.P.-G. acknowledges support from the Spanish Programa Nacional de Astronomía y Astrofísica under grants AYA 2006– 02358 and AYA 2006–15698–C02–02, and from the Ramón y Cajal Program financed by the Spanish Government and the European Union.
NO Ministerio de Economía y Competitividad (MINECO)
NO National Aeronautics and Space Administration (NASA)
NO Leo Goldberg Fellowship
NO National Optical Astronomy Observatory (NOAO), EE.UU.
NO Programa Nacional de Astronomía y Astrofísica (PNAyA), España
NO Unión Europea (UE)
NO Ayudas para contratos Ramón y Cajal (RYC), MINECO
DS Docta Complutense
RD 10 abr 2025