SIMBAD references

2008ApJ...672..177L - Astrophys. J., 672, 177-197 (2008/January-1)

The evolution of galaxy mergers and morphology at z < 1.2 in the Extended Groth Strip.

LOTZ J.M., DAVIS M., FABER S.M., GUHATHAKURTA P., GWYN S., HUANG J., KOO D.C., LE FLOC'H E., LIN L., NEWMAN J., NOESKE K., PAPOVICH C., WILLMER C.N.A., COIL A., CONSELICE C.J., COOPER M., HOPKINS A.M., METEVIER A., PRIMACK J., RIEKE G. and WEINER B.J.

Abstract (from CDS):

We present the quantitative rest-frame B morphological evolution and galaxy merger fraction at 0.2<z<1.2 as observed by the All-Wavelength Extended Groth Strip International Survey (AEGIS). We use the Gini coefficient and M20 to identify major mergers and classify galaxy morphology for a volume-limited sample of 3009 galaxies brighter than 0.4L*B, assuming pure luminosity evolution. We find that the merger fraction remains roughly constant at 10%±2% for 0.2<z<1.2. The fraction of E/S0/Sa galaxies increases from 21%±3% at z∼1.1 to 44%±9% at z∼0.3, while the fraction of Sb-Ir galaxies decreases from 64%±6% at z∼1.1 to 47%±9% at z∼0.3. The majority of z<1.2 Spitzer MIPS 24 µm sources with L(IR)>1011 Lare disk galaxies, and only ∼15% are classified as major merger candidates. Edge-on and dusty disk galaxies (Sb-Ir) are almost a third of the red sequence at z∼1.1, while E/S0/Sa make up over 90% of the red sequence at z∼0.3. Approximately 2% of our full sample are red mergers. We conclude (1) the merger rate does not evolve strongly between 0.2<z<1.2; (2) the decrease in the volume-averaged star formation rate density since z∼1 is a result of declining star formation in disk galaxies rather than a disappearing population of major mergers; (3) the build-up of the red sequence at z<1 can be explained by a doubling in the number of spheroidal galaxies since z∼1.2.

Abstract Copyright:

Journal keyword(s): Galaxies: Evolution - Galaxies: High-Redshift - Galaxies: Interactions - Galaxies: Structure

Simbad objects: 6

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2008ApJ...672..177L and select 'bookmark this link' or equivalent in the popup menu