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We present the results of an integral field spectroscopy survey of a sample of dusty (ultra) luminous infrared galaxies (U/LIRGs) at 2 < z < 2.5 using KMOS on the Very Large Telescope. The sample has been drawn from Herschel deep field surveys and benefits from ancillary multiwavelength data. Our goal is to investigate the physical characteristics, kinematics, and the drivers of star formation in the galaxies whose contribution dominates the peak of the cosmic star formation density. Two-thirds of the sample are main-sequence galaxies in contrast to the starburst nature of local U/LIRGs. Our kinematic study, unique in its focus on z ∼ 2 dusty star-forming galaxies, uses the H α emission line to find that ∼40 per cent appear to be isolated discs based on the ratio of rotational velocity to the velocity dispersion, suggesting steady-state mechanisms are sufficient to power the large star formation rates (SFRs). The ratio of obscured to unobscured star formation indicates the sample of galaxies experiences less dust obscuration compared to intermediate and local counterparts, while also hosting cooler dust than local U/LIRGs. In addition to H α we detect [N  ii ] 6583 Å in our targets and show the gas-phase metallicities do not exhibit the metal deficiency of local U/LIRGs. These results indicate that, despite their extreme IR luminosity, the underlying mechanisms driving the massive SFRs found at cosmic noon are due to scaled up disc galaxies as opposed to mergers. [ABSTRACT FROM AUTHOR]

We present detailed simulations of integral field spectroscopic observations of a supernova in a host galaxy at z  ∼ 3, as observed by the HARMONI spectrograph on the Extremely Large Telescope, assisted by laser tomographic adaptive optics. The goal of the simulations, using the HSIM simulation tool, is to determine whether HARMONI can discern the supernova type from spectral features in the supernova spectrum. We find that in a 3 h observation, covering the near-infrared H and K bands, at a spectral resolving power of ∼3000, and using the 20 × 20 mas spaxel scale, we can classify Type Ia supernovae and their redshift robustly up to 80 d past maximum light (20 d in the supernova rest frame). We show that HARMONI will provide spectra at z  ∼ 3, which are of comparable (or better) quality to the best spectra we can currently obtain at z  ∼ 1, thus allowing studies of cosmic expansion rates to be pushed to substantially higher redshifts. [ABSTRACT FROM AUTHOR]

We present a study into the capabilities of integrated and spatially resolved integral field spectroscopy of galaxies at z = 2-4 with the future HARMONI spectrograph for the European Extremely Large Telescope (E-ELT) using the simulation pipeline, hsim. We focus particularly on the instrument's capabilities in stellar absorption line integral field spectroscopy, which will allow us to study the stellar kinematics and stellar population characteristics. Such measurements for star-forming and passive galaxies around the peak star formation era will provide a critical insight into the star formation, quenching and mass assembly history of high-z, and thus present-day galaxies. First, we perform a signal-to-noise study for passive galaxies at a range of stellar masses for z = 2-4, assuming different light profiles; for this population, we estimate that integrated stellar absorption line spectroscopy with HARMONI will be limited to galaxies with M* ≳ 1010.7 M⊙. Secondly, we use hsim to perform a mock observation of a typical star-forming 1010 M⊙ galaxy at z = 3 generated from the high-resolution cosmological simulation nutfb. We demonstrate that the input stellar kinematics of the simulated galaxy can be accurately recovered from the integrated spectrum in a 15-h observation, using common analysis tools. Whilst spatially resolved spectroscopy is likely to remain out of reach for this particular galaxy, we estimate HARMONI's performance limits in this regime from our findings. This study demonstrates how instrument simulators such as hsim can be used to quantify instrument performance and study observational biases on kinematics retrieval; and shows the potential of making observational predictions from cosmological simulation output data. [ABSTRACT FROM AUTHOR]

We present hsim: a dedicated pipeline for simulating observations with the High Angular Resolution Monolithic Optical and Near-infrared Integral field spectrograph (HARMONI) on the European Extremely Large Telescope. hsim takes high spectral and spatial resolution input data cubes, encoding physical descriptions of astrophysical sources, and generates mock observed data cubes. The simulations incorporate detailed models of the sky, telescope and instrument to produce realistic mock data. Further, we employ a new method of incorporating the strongly wavelength-dependent adaptive optics point spread functions. hsim provides a step beyond traditional exposure time calculators and allows us to both predict the feasibility of a given observing programme with HARMONI and perform instrument design trade-offs. In this paper, we concentrate on quantitative measures of the feasibility of planned observations. We give a detailed description of hsim and present two studies: estimates of point source sensitivities along with simulations of star-forming emission-line galaxies at z ~ 2-3. We show that HARMONI will provide exquisite resolved spectroscopy of these objects on sub-kpc scales, probing and deriving properties of individual star-forming regions. [ABSTRACT FROM AUTHOR]

ABSTRACT The 'Eagle' galaxy at a redshift of 0.77 is studied with the Oxford Short Wavelength Integral Field Spectrograph (SWIFT) and multiwavelength data from the All-wavelength Extended Groth strip International Survey (AEGIS). It was chosen from AEGIS because of the bright and extended emission in its slit spectrum. 3D kinematic maps of the Eagle reveal a gradient in velocity dispersion which spans 35-75 ± 10 km s−1 and a rotation velocity of 25 ± 5 km s−1 uncorrected for inclination. Hubble Space Telescope images suggest it is close to face-on. In comparison with galaxies from AEGIS at similar redshifts, the Eagle is extremely bright and blue in the rest-frame optical, highly star forming, dominated by unobscured star formation and has a low metallicity for its size. This is consistent with its selection. The Eagle is likely undergoing a major merger and is caught in the early stage of a starburst when it has not yet experienced metal enrichment or formed the mass of dust typically found in star-forming galaxies. [ABSTRACT FROM AUTHOR]