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arXiv · 0806.0657

Spectroscopic Confirmation Of An Extreme Starburst At Redshift 4.547

Peter Capak·C. L. Carilli·N. Lee·T. Aldcroft·H. Aussel·E. Schinnerer·G. W. Wilson·M. S. Yun·A . Blain·M. Giavalisco·O. Ilbert·J. Kartaltepe·K. -S. Lee·H. McCracken·B. Mobasher·M. Salvato·S. Sasaki·K. S. Scott·K. Sheth·Y. Shioya·D. Thompson·M. Elvis·D. B. Sanders·N. Z. Scoville·Y. Tanaguchi
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Abstract

We report the spectroscopic confirmation of a sub-mm galaxy (SMG) at z=4.547 with an estimated L_IR=0.5-2.0x10^13 L_sun. The spectra, mid-IR, and X-ray properties indicate the bolometric luminosity is dominated by star formation at a rate of >1000M_sun per yr. Multiple, spatially separated components are visible in the Ly-Alpha line with an observed velocity difference of up to 380 km/sec and the object morphology indicates a merger. The best fit spectral energy distribution and spectral line indicators suggest the object is 2-8 Myr old and contains >10^10 M_sun of stellar mass. This object is a likely progenitor for the massive early type systems seen at z~2.

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Peter Capak, C. L. Carilli, N. Lee, T. Aldcroft, H. Aussel, E. Schinnerer, G. W. Wilson, M. S. Yun, A . Blain, M. Giavalisco, O. Ilbert, J. Kartaltepe, K. -S. Lee, H. McCracken, B. Mobasher, M. Salvato, S. Sasaki, K. S. Scott, K. Sheth, Y. Shioya, D. Thompson, M. Elvis, D. B. Sanders, N. Z. Scoville, Y. Tanaguchi. 2008-06-03. Spectroscopic Confirmation Of An Extreme Starburst At Redshift 4.547. https://doi.org/10.1086/590555

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