HERSCHEL DETECTION OF DUST EMISSION FROM UV-LUMINOUS STAR-FORMING GALAXIES AT 3.3 {approx}< z {approx}< 4.3

Journal Article · Sat Oct 20 04:00:00 EDT 2012 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/758/2/L31· OSTI ID:22078488

Lee, Kyoung-Soo ^[1]; Alberts, Stacey; Pope, Alexandra ^[2]; Atlee, David; Dey, Arjun; Jannuzi, Buell T ^[3]; Reddy, Naveen ^[4]; Brown, Michael J. I. ^[5]

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1. Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907 (United States)
2. Department of Astronomy, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003 (United States)
3. National Optical Astronomy Observatory, Tucson, AZ 85726 (United States)
4. Department of Physics and Astronomy, University of California, Riverside, 900 University Avenue, Riverside, CA 92521 (United States)
5. School of Physics, Monash University, Clayton, Victoria 3800 (Australia)

We report the Herschel/SPIRE detection of dust emission arising from UV-luminous (L {approx}> L*) star-forming galaxies at 3.3 {approx}< z {approx}< 4.3. Our sample of 1913 Lyman break galaxy (LBG) candidates is selected over an area of 5.3 deg{sup 2} in the Booetes field of the NOAO Deep Wide-Field Survey. This is one of the largest samples of UV-luminous galaxies at this epoch and enables an investigation of the bright end of the galaxy luminosity function. We divide our sample into three luminosity bins and stack the Herschel/SPIRE data to measure the average spectral energy distribution (SED) of LBGs at far-infrared (FIR) wavelengths. We find that these galaxies have average IR luminosities of (3-5) Multiplication-Sign 10{sup 11} L{sub Sun} and 60%-70% of their star formation obscured by dust. The FIR SEDs peak at {lambda}{sub rest} {approx}> 100 {mu}m suggesting dust temperatures (T{sub d} = 27-30 K) significantly colder than that of local galaxies of comparable IR luminosities. The observed IR-to-UV luminosity ratio (IRX {identical_to} L{sub IR}/L{sub UV}) is low ( Almost-Equal-To 3-4) compared with that observed for z Almost-Equal-To 2 LBGs (IRX{sub z{approx}2} Almost-Equal-To 7.1 {+-} 1.1). The correlation between the slope of the UV continuum and IRX for galaxies in the two lower luminosity bins suggests dust properties similar to those of local starburst galaxies. However, the galaxies in the highest luminosity bin appear to deviate from the local relation, suggesting that their dust properties may differ from those of their lower-luminosity and low-redshift counterparts. We speculate that the most UV-luminous galaxies at this epoch are being observed in a short-lived and young evolutionary phase.

• OSTI ID: 22078488
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 758; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COSMIC DUST
EMISSION
ENERGY SPECTRA
FAR INFRARED RADIATION
LUMINOSITY
MILKY WAY
RED SHIFT
ULTRAVIOLET SPECTRA
WAVELENGTHS