Tracing Recent Star Formation of Red Early-type Galaxies out to $z$ $\sim$ 1

Abstract

We study the mid-infrared (IR) excess emission of early-type galaxies (ETGs) on the red-sequence at $z<$ 1 using a spectroscopic sample of galaxies in the fields of Great Observatories Origins Deep Survey (GOODS). In the mass-limited sample of 1025 galaxies with $M_{star}$ $>$ 10${}^{10.5}$ $M_{\odot }$ and $0.4<z<1.05$, we identify 696 $Spitzer$ 24 $\mu$m detected (above the 5$\sigma$) galaxies and find them to have a wide range of NUV-$r$ and $r$-[12 $\mu$m] colors despite their red optical $u-r$ colors. Even in the sample of very massive ETGs on the red sequence with $M_{star}$ $>$ 10${}^{11.2}$ $M_{\odot }$, more than 18% show excess emission over the photospheric emission in the mid-IR. The combination with the results of red ETGs in the local universe suggests that the recent star formation is not rare among quiescent, red ETGs at least out to $z\sim 1$ if the mid-IR excess emission results from intermediate-age stars or/and from low-level ongoing star formation. Our color$-$color diagram including near-UV and mid-IR emissions are efficient not only for identifying ETGs with recent star formation, but also for distinguishing quiescent galaxies from dusty star-forming galaxies.

25 pages, 9 figures, accepted for publication in ApJ

References in corpus (16)

• Cold streams in early massive hot haloes as the main mode of galaxy formation
• Galaxy Zoo: the dependence of morphology and colour on environment
• PRIMUS: Constraints on Star Formation Quenching and Galaxy Merging, and the Evolution of the Stellar Mass Function From z=0-1
• The 0.4 < z < 1.3 star formation history of the Universe as viewed in the far-infrared
• The stellar masses of 25000 galaxies at 0.2<z<1.0 estimated by the COMBO-17 survey
• The Great Observatories Origins Deep Survey. VLT/VIMOS Spectroscopy in the GOODS-South Field
• A Spectroscopic Survey of Redshift 1.4<z<3.0 Galaxies in the Goods-North Field: Survey Description, Catalogs, and Properties
• The STAGES view of red spirals and dusty red galaxies: Mass-dependent quenching of star-formation in cluster infall
• The role of minor mergers in the recent star formation history of early-type galaxies
• Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4
• The UV properties of E+A galaxies: constraints on feedback-driven quenching of star formation
• SPITZER IRS spectra of Virgo early type galaxies: detection of stellar silicate emission
• The mid-infrared colour-magnitude relation of early-type galaxies in the Coma cluster as measured by Spitzer-IRS
• Evidence for Morphology and Luminosity Transformation of Galaxies at High Redshifts
• The Nature of Blue Early-Type Galaxies in the Goods Fields
• The Fundamental Planes of E+A galaxies and GALEX UV-excess early-type galaxies: Revealing their intimate connection

Cited by in corpus (1)

• Intracluster Light Properties in a Fossil Cluster at z=0.47