The FMOS-COSMOS Survey of Star-forming Galaxies at Z ~ 1.6. V: Properties of Dark Matter Halos Containing Hα Emitting Galaxies
We study the properties of dark matter halos that contain star-forming galaxies at 1.43 ≤ z ≤ 1.74, using the FMOS-COSMOS survey. The sample consists of 516 objects with a detection of the Hα emission line, which represent the star forming population at this epoch, having a stellar mass range of 10^9.57 ≤ M */M ⊙ lesssim 10^11.4 and a star-formation rate range of 15 lesssim SFR/(M ⊙ yr^−1) lesssim ^600. We measure the projected two-point correlation function while carefully taking into account observational biases, and find a significant clustering amplitude at scales of 0.04–10 h ^−1 cMpc, with a correlation length r0 =5.26-0.62^+0.75h^-1cMpc and a bias b =2.44-0.32^+0.38. We interpret our clustering measurement using a halo occupation distribution model. The sample galaxies appear to reside in halos with mass Mh=4.71-1.62^+1.19×10^12h^-1,M⊙ on average, which will likely become present-day halos of mass M h (z = 0) ~ 2 × 10^13 h ^−1 M ⊙, equivalent to the typical halo mass scale of galaxy groups. We then confirm the decline of the stellar-to-halo mass ratio at M h < 10^12 M ⊙, finding M */M h ≈ 5 × 10^−3 at M h = 7. 5 × 10^11 M ⊙, which is lower by a factor of 2–4 than those measured at higher masses (M h ~ 10^12–13 M ⊙). Finally, we use our results to illustrate the future capabilities of Subaru's Prime-Focus Spectrograph, a next-generation instrument that will provide strong constraints on the galaxy-formation scenario by obtaining precise measurements of galaxy clustering at z>1.
- Astrophysical Journal
Astrophysical Journal 843(2), 138-138, 2017-07-10