Keck-I MOSFIRE spectroscopy of compact star-forming galaxies at z ≳ 2: high velocity dispersions in progenitors of compact quiescent galaxies

• Published in: The Astrophysical journal 2014-11, Vol.795 (2)
• Main Authors: Barro, Guillermo, Koo, David C., Faber, Sandra M., Guo, Yicheng, Toloba, Elisa, Fang, Jerome J., Trump, Jonathan R., Dekel, Avishai, Kassin, Susan A., Koekemoer, Anton M., Kocevski, Dale D., Van der Wel, Arjen, Pérez-González, Pablo G., Pacifici, Camilla, Simons, Raymond, Campbell, Randy D., Goodrich, Bob, Kassis, Marc, Ceverino, Daniel, Finkelstein, Steven L.
• Format: Article
• Language: English
• Subjects: ABSORPTION; ABSORPTION SPECTROSCOPY; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPACTS; DISPERSIONS; EMISSION; GALAXIES; INFRARED SPECTRA; INFUSION; MASS; NEAR INFRARED RADIATION; NONLUMINOUS MATTER; PHOTOMETRY; RED SHIFT; STARS; VELOCITY
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/795/2/145

We present Keck-I MOSFIRE near-infrared spectroscopy for a sample of 13 compact star-forming galaxies (SFGs) at redshift 2 ≤ z ≤ 2.5 with star formation rates of SFR ∼ 100 M {sub ☉} yr{sup –1} and masses of log(M/M {sub ☉}) ∼10.8. Their high integrated gas velocity dispersions of σ{sub int} =230{sub −30}{sup +40} km s{sup –1}, as measured from emission lines of Hα and [O III], and the resultant M {sub *}-σ{sub int} relation and M {sub *}-M {sub dyn} all match well to those of compact quiescent galaxies at z ∼ 2, as measured from stellar absorption lines. Since log(M {sub *}/M {sub dyn}) =–0.06 ± 0.2 dex, these compact SFGs appear to be dynamically relaxed and evolved, i.e., depleted in gas and dark matter (