%0 Generic %1 karman2013restframe %A Karman, W. %A Caputi, K. I. %A Trager, S. C. %A Almaini, O. %A Cirasuolo, M. %D 2013 %K galaxies lbg massive outflows velocity %T Rest-frame ultra-violet spectra of massive galaxies at z=3: evidence for high-velocity outflows %U http://arxiv.org/abs/1311.5761 %X Galaxy formation models invoke the presence of strong feedback mechanisms that regulate the growth of massive galaxies at high redshifts. In this paper we aim to: (1) confirm spectroscopically the redshifts of a sample of massive galaxies selected with photometric redshifts larger than 2.5; (2) investigate the properties of their stellar and interstellar media; (3) detect the presence of outflows, and measure their velocities. To achieve this, we analysed deep, high-resolution (R=2000) FORS2 rest-frame UV spectra for 11 targets. We confirmed that 9 out of 11 have spectroscopic redshifts larger than 2.5. We also serendipitously found two mask fillers at redshift larger than 2.5, which originally were assigned photometric redshifts between 2.0 and 2.5. In the four highest-quality spectra we derived outflow velocities by fitting the absorption line profiles with models including multiple dynamical components. We found strongly asymmetric, high-ionisation lines, from which we derived outflow velocities ranging between 480 and 1528 km/s. We revised the spectral energy distribution fitting U-band through 8 micron photometry, including the analysis of a power-law component subtraction to identify the possible presence of active galactic nuclei (AGN). The revised stellar masses of all but one of our targets are larger than 1e10 solar masses, with four having stellar masses 5e10 solar masses. Three galaxies have a significant power-law component in their spectral energy distributions, which indicates that they host AGN. We conclude that massive galaxies are characterised by significantly higher velocity outflows than the typical Lyman break galaxies at redshifts around 3. The incidence of high-velocity outflows (approximately 40 per cent within our sample) is also much higher than among massive galaxies at redshifts below 1. (Abridged)

@misc{karman2013restframe, abstract = {Galaxy formation models invoke the presence of strong feedback mechanisms that regulate the growth of massive galaxies at high redshifts. In this paper we aim to: (1) confirm spectroscopically the redshifts of a sample of massive galaxies selected with photometric redshifts larger than 2.5; (2) investigate the properties of their stellar and interstellar media; (3) detect the presence of outflows, and measure their velocities. To achieve this, we analysed deep, high-resolution (R=2000) FORS2 rest-frame UV spectra for 11 targets. We confirmed that 9 out of 11 have spectroscopic redshifts larger than 2.5. We also serendipitously found two mask fillers at redshift larger than 2.5, which originally were assigned photometric redshifts between 2.0 and 2.5. In the four highest-quality spectra we derived outflow velocities by fitting the absorption line profiles with models including multiple dynamical components. We found strongly asymmetric, high-ionisation lines, from which we derived outflow velocities ranging between 480 and 1528 km/s. We revised the spectral energy distribution fitting U-band through 8 micron photometry, including the analysis of a power-law component subtraction to identify the possible presence of active galactic nuclei (AGN). The revised stellar masses of all but one of our targets are larger than 1e10 solar masses, with four having stellar masses 5e10 solar masses. Three galaxies have a significant power-law component in their spectral energy distributions, which indicates that they host AGN. We conclude that massive galaxies are characterised by significantly higher velocity outflows than the typical Lyman break galaxies at redshifts around 3. The incidence of high-velocity outflows (approximately 40 per cent within our sample) is also much higher than among massive galaxies at redshifts below 1. (Abridged)}, added-at = {2013-11-25T18:34:12.000+0100}, author = {Karman, W. and Caputi, K. I. and Trager, S. C. and Almaini, O. and Cirasuolo, M.}, biburl = {https://www.bibsonomy.org/bibtex/2db5279d30fb0f0a2c9251ef62d74849a/miki}, description = {[1311.5761] Rest-frame ultra-violet spectra of massive galaxies at z=3: evidence for high-velocity outflows}, interhash = {819ca346e26d5da4a2c3fc15897bb1c1}, intrahash = {db5279d30fb0f0a2c9251ef62d74849a}, keywords = {galaxies lbg massive outflows velocity}, note = {cite arxiv:1311.5761Comment: 17 pages, 14 figures, Submintted to A&A}, timestamp = {2013-11-25T18:34:12.000+0100}, title = {Rest-frame ultra-violet spectra of massive galaxies at z=3: evidence for high-velocity outflows}, url = {http://arxiv.org/abs/1311.5761}, year = 2013 }