FMOS near-IR spectroscopy of Herschel-selected galaxies: star formation rates, metallicity and dust attenuation at z similar to 1

I. G. Roseboom, A. Bunker, M. Sumiyoshi, L. Wang, G. Dalton, M. Akiyama, J. Bock, D. Bonfield, V. Buat, C. Casey, E. Chapin, D. L. Clements, A. Conley, E. Curtis-Lake, A. Cooray, J. S. Dunlop, D. Farrah, S. J. Ham, E. Ibar, F. IwamuroM. Kimura, I. Lewis, E. Macaulay, G. Magdis, T. Maihara, G. Marsden, T. Mauch, Y. Moritani, K. Ohta, S. J. Oliver, M. J. Page, B. Schulz, Douglas Scott, M. Symeonidis, N. Takato, N. Tamura, T. Totani, K. Yabe, M. Zemcov

Research output: Contribution to journalArticlepeer-review

Abstract

We investigate the properties (e.g. star formation rate, dust attenuation, stellar mass and metallicity) of a sample of infrared (IR) luminous galaxies at z similar to 1 via near-IR spectroscopy with Subaru-FMOS. Our sample consists of Herschel SPIRE and Spitzer MIPS selected sources in the COSMOS field with photometric redshifts in the range of 0.7 <zphot <1.8, which have been targeted in two pointings (0.5 deg2) with FMOS. We find a modest success rate for emission-line detections, with candidate Ha emission lines detected for 57 of 168 SPIRE sources (34 per cent). By stacking the near-IR spectra we directly measure the mean Balmer decrement for the Ha and H beta lines, finding a value of <E(B - V)> = 0.51 +/- 0.27 for <LIR > = 1012L circle dot sources at <z > = 1.36. By comparing star formation rates estimated from the IR and from the dust-uncorrected Ha line we find a strong relationship between dust attenuation and star formation rate. This relation is broadly consistent with that previously seen in star-forming galaxies at z similar to 0.1. Finally, we investigate the metallicity via the N2 ratio, finding that z similar to 1 IR-selected sources are indistinguishable from the local massmetallicity relation. We also find a strong correlation between dust attenuation and metallicity, with the most metal-rich IR sources experiencing the largest levels of dust attenuation.

Original languageEnglish
Pages (from-to)1782-1792
Number of pages11
JournalMonthly Notices of the Royal Astronomical Society
Volume426
Issue number3
DOIs
Publication statusPublished - Nov 2012

Keywords

  • galaxies: evolution
  • submillimetre: galaxies
  • VLT DEEP SURVEY
  • FAR-INFRARED PROPERTIES
  • HIGH-REDSHIFT GALAXIES
  • DIGITAL SKY SURVEY
  • FORMING GALAXIES
  • MASS-METALLICITY
  • EXTRAGALACTIC SURVEY
  • STELLAR MASS
  • H-ALPHA
  • PHOTOMETRIC REDSHIFTS

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