%0 Generic %1 wuyts2016kmos3d %A Wuyts, S. %A Schreiber, N. M. Förster %A Wisnioski, E. %A Genzel, R. %A Burkert, A. %A Bandara, K. %A Beifiori, A. %A Belli, S. %A Bender, R. %A Brammer, G. B. %A Chan, J. %A Davies, R. %A Fossati, M. %A Galametz, A. %A Kulkarni, S. K. %A Lang, P. %A Lutz, D. %A Mendel, J. T. %A Momcheva, I. G. %A Naab, T. %A Nelson, E. J. %A Saglia, R. P. %A Seitz, S. %A Tacconi, L. J. %A Tadaki, K. %A Übler, H. %A van Dokkum, P. G. %A Wilman, D. J. %A Wuyts, E. %D 2016 %K baryon budget disks high-z %T KMOS^3D: Dynamical constraints on the mass budget in early star-forming disks %U http://arxiv.org/abs/1603.03432 %X We exploit deep integral-field spectroscopic observations with KMOS/VLT of 240 star-forming disks at 0.6 < z < 2.6 to dynamically constrain their mass budget. Our sample consists of massive ($10^9.8 M_ødot$) galaxies with sizes $R_e 2$ kpc. By contrasting the observed velocity and dispersion profiles to dynamical models, we find that on average the stellar content contributes 31% of the total dynamical mass, with a significant spread among galaxies (68th percentile range f_star ~ 16 - 60%). Including molecular gas as inferred from CO- and dust-based scaling relations, the estimated baryonic mass adds up to 63% of total for the typical galaxy in our sample. We conclude that baryons make up most of the mass within the disk regions of high-redshift star-forming galaxies, with nearly all disks at z > 2 being strongly baryon-dominated within $R_e$. Substantial object-to-object variations in both stellar and baryonic mass fractions are observed among the galaxies in our sample, larger than what can be accounted for by the formal uncertainties in their respective measurements. In both cases, the mass fractions correlate most strongly with measures of surface density. High $\Sigma_star$ galaxies feature stellar mass fractions closer to unity, and systems with high inferred gas or baryonic surface densities leave less room for additional mass components other than stars and molecular gas. Our findings can be interpreted as more extended disks probing further (and more compact disks probing less far) into the dark matter halos that host them. However, a non-negligible tail of the derived baryonic mass fraction distribution reaching into the unphysical $f_bar > 1$ regime may in addition hint at more efficient star formation in high surface density disks than adopted in our methodology.

@misc{wuyts2016kmos3d, abstract = {We exploit deep integral-field spectroscopic observations with KMOS/VLT of 240 star-forming disks at 0.6 < z < 2.6 to dynamically constrain their mass budget. Our sample consists of massive ($\gtrsim 10^{9.8} M_\odot$) galaxies with sizes $R_e \gtrsim 2$ kpc. By contrasting the observed velocity and dispersion profiles to dynamical models, we find that on average the stellar content contributes 31% of the total dynamical mass, with a significant spread among galaxies (68th percentile range f_star ~ 16 - 60%). Including molecular gas as inferred from CO- and dust-based scaling relations, the estimated baryonic mass adds up to 63% of total for the typical galaxy in our sample. We conclude that baryons make up most of the mass within the disk regions of high-redshift star-forming galaxies, with nearly all disks at z > 2 being strongly baryon-dominated within $R_e$. Substantial object-to-object variations in both stellar and baryonic mass fractions are observed among the galaxies in our sample, larger than what can be accounted for by the formal uncertainties in their respective measurements. In both cases, the mass fractions correlate most strongly with measures of surface density. High $\Sigma_{star}$ galaxies feature stellar mass fractions closer to unity, and systems with high inferred gas or baryonic surface densities leave less room for additional mass components other than stars and molecular gas. Our findings can be interpreted as more extended disks probing further (and more compact disks probing less far) into the dark matter halos that host them. However, a non-negligible tail of the derived baryonic mass fraction distribution reaching into the unphysical $f_{bar} > 1$ regime may in addition hint at more efficient star formation in high surface density disks than adopted in our methodology.}, added-at = {2016-03-14T09:41:21.000+0100}, author = {Wuyts, S. and Schreiber, N. M. Förster and Wisnioski, E. and Genzel, R. and Burkert, A. and Bandara, K. and Beifiori, A. and Belli, S. and Bender, R. and Brammer, G. B. and Chan, J. and Davies, R. and Fossati, M. and Galametz, A. and Kulkarni, S. K. and Lang, P. and Lutz, D. and Mendel, J. T. and Momcheva, I. G. and Naab, T. and Nelson, E. J. and Saglia, R. P. and Seitz, S. and Tacconi, L. J. and Tadaki, K. and Übler, H. and van Dokkum, P. G. and Wilman, D. J. and Wuyts, E.}, biburl = {https://www.bibsonomy.org/bibtex/27e05c8ee51c02d1a18411fb22457254d/miki}, description = {[1603.03432] KMOS^3D: Dynamical constraints on the mass budget in early star-forming disks}, interhash = {8ae60f4f769c8f01209096b9f585264b}, intrahash = {7e05c8ee51c02d1a18411fb22457254d}, keywords = {baryon budget disks high-z}, note = {cite arxiv:1603.03432Comment: Submitted to ApJ. Fig. 4 compares stellar and baryonic masses to dynamical masses. Fig. 6 and 7 show the dependence of stellar and baryonic mass fractions on redshift and surface density}, timestamp = {2016-03-14T09:41:21.000+0100}, title = {KMOS^3D: Dynamical constraints on the mass budget in early star-forming disks}, url = {http://arxiv.org/abs/1603.03432}, year = 2016 }