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We analyze JWST NIRSpec+MIRI/MRS observations of the infrared (IR) gas-phase molecular bands of the most enshrouded source (D1) within the interacting system and luminous IR galaxy II Zw 096. We report the detection of rovibrational lines of H2O ν2 = 1 − 0 (∼5.3–7.2 μm) and 12CO ν = 1 − 0 (∼4.45–4.95 μm) in D1. The CO band shows the R- and P-branches in emission and the spectrum of the H2O band shows the P-branch in emission and the R-branch in absorption. The H2O R-branch in absorption unveils an IR-bright embedded compact source in D1 and the CO broad component features a highly turbulent environment. From both bands, we also identified extended intense star-forming (SF) activity associated with circumnuclear photodissociation regions (PDRs), consistent with the strong emission of the ionised 7.7 μm polycyclic aromatic hydrocarbon band in this source. By including the 4.5–7.0 μm continuum information derived from the H2O and CO analysis, we modelled the IR emission of D1 with a dusty torus and SF component. The torus is very compact (diameter of ∼3 pc at 5 μm) and characterised by warm dust (∼370 K), giving an IR surface brightness of ∼3.6 × 108 L⊙ pc−2. This result suggests the presence of a dust-obscured active galactic nucleus (AGN) in D1, which has an exceptionally high covering factor that prevents the direct detection of AGN emission. Our results open a new way to investigate the physical conditions of inner dusty tori via modelling the observed IR molecular bands. [ABSTRACT FROM AUTHOR]

We present a CO(3−2) study of four systems composed of six (ultra) luminous infrared galaxies (U/LIRGs), located at 0.28 < z < 0.44, that straddle the transition region between regular star-forming galaxies and starbursts. These galaxies benefit from previous multiwavelength analysis allowing in depth exploration of an understudied population of U/LIRGs at a time when the universe is experiencing a rapid decline in star formation rate density. We detect CO(3−2) emission in four targets and these galaxies fall between the loci of regular star-forming galaxies and starbursts on the Kennicutt–Schmidtt relation. Compared to low luminosity LIRGs and high luminosity ULIRGs at similar redshifts, we find they all have similar molecular gas budgets with the difference in their star formation rates (SFR) driven by the star formation efficiency (SFE). This suggests that at these redshifts large molecular gas reservoirs must coincide with an increased SFE to transition a galaxy into the starburst regime. We studied the structure and kinematics and found our four detections are either interacting or have disturbed morphology which may be driving the SFE. One of the CO(3−2) non-detections has a strong continuum detection, and has been previously observed in H α, suggesting an unusual interstellar medium for a ULIRG. We conclude that our sample of transitioning U/LIRGs fill the gap between regular star-forming galaxies and starbursts, suggest a continuous change in SFE between these two populations and the increased SFE may be driven by morphology and differing stages of interaction. [ABSTRACT FROM AUTHOR]

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 simulate the flux emitted from galaxy haloes in order to quantify the brightness of the circumgalactic medium (CGM). We use dedicated zoom-in cosmological simulations with the hydrodynamical adaptive mesh refinement code ramses , which are evolved down to z  = 0 and reach a maximum spatial resolution of 380 h −1 pc and a gas mass resolution up to |$1.8\times 10^{5} \, h^{-1}\, \rm {M}_{\odot }$| in the densest regions. We compute the expected emission from the gas in the CGM using cloudy emissivity models for different lines (e.g. Lyα, C  iv , O  vi , C  vi , O  viii) considering UV background fluorescence, gravitational cooling and continuum emission. In the case of Lyα, we additionally consider the scattering of continuum photons. We compare our predictions to current observations and find them to be in good agreement at any redshift after adjusting the Lyα escape fraction. We combine our mock observations with instrument models for Faint Intergalactic Redshifted Emission Balloon-2 (FIREBall-2; UV balloon spectrograph) and HARMONI (visible and NIR IFU on the ELT) to predict CGM observations with either instrument and optimize target selections and observing strategies. Our results show that Lyα emission from the CGM at a redshift of 0.7 will be observable with FIREBall-2 for bright galaxies (NUV∼18 mag), while metal lines like O  vi and C  iv will remain challenging to detect. HARMONI is found to be well suited to study the CGM at different redshifts with various tracers. [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 We present observations of Arp 147, a galaxy system comprising a collisionally created ring galaxy and an early-type galaxy, using the Oxford SWIFT integral field spectrograph (IFS) at the 200-inch Hale telescope. We derive spatially resolved kinematics from the IFS data and use these to study the interaction between the two galaxies. We find the edge-to-edge expansion velocity of the ring is 225 ± 8 km s−1, implying an upper limit on the time-scale for the collision of 50 Myr. We also calculate that the angle of impact for the collision is between , where 0° would imply a perpendicular collision. The ring galaxy is strongly star forming with the star formation likely to have been triggered by the collision between the two galaxies. We also measure some key physical parameters in an integrated and spatially resolved manner for the ring galaxy. Using the observed B− I colours and the Hα equivalent widths, we conclude that two stellar components (a young and an old population) are required everywhere in the ring to simultaneously match both observed quantities. We are able to constrain the age range, light and mass fractions of the young star formation activity in the ring, finding a modest age range, a light fraction of less than a third, and a negligible (<1 per cent) mass fraction. We postulate that the redder colours observed in the south-east corner of the ring galaxy could correspond to the nuclear bulge of the original disc galaxy from which the ring was created, consistent with the stellar mass in the south-east quadrant being 30-50 per cent of the total. The ring appears to have been a typical disc galaxy prior to the encounter. The ring shows electron densities consistent with typical values for star-forming H ii regions. The eastern half of the ring exhibits a metallicity a factor of ∼2 higher than the western half. The ionization parameter, measured across the ring, roughly follows the previously observed trend with metallicity. [ABSTRACT FROM AUTHOR]

Efforts to formalise the role of traditional birth attendants (TBAs) in maternal and neonatal health programmes have had limited success. TBAs' continued attendance at home deliveries suggests the potential to influence maternal and neonatal outcomes. The objective of this qualitative study was to identify and understand the knowledge, attitudes and practices of TBAs in rural Nepal. Twenty-one trained and untrained TBAs participated in focus groups and in-depth interviews about antenatal care, delivery practices, maternal complications and newborn care. Antenatal care included advice about nutrition and tetanus toxoid (TT) immunisation, but did not include planning ahead for transport in cases of complications. Clean delivery practices were observed by most TBAs, though hand-washing practices differed by training status. There was no standard practice to identify maternal complications, such as excessive bleeding, prolonged labour, or retained placenta, and most referred outside in the event of such complications. Newborn care practices included breastfeeding with supplemental feeds, thermal care after bathing, and mustard seed oil massage. TBAs reported high job satisfaction and desire to improve their skills. Despite uncertainty regarding the role of TBAs to manage maternal complications, TBAs may be strategically placed to make potential contributions to newborn survival. [ABSTRACT FROM AUTHOR]

We combine VLT/ISAAC near-infrared (NIR) spectroscopy with archival HST/WFPC2 and HST/NICMOS imaging to study the central 20 × 20 arcsec2 of M83. Our NIR indices for clusters in the circumnuclear starburst region are inconsistent with simple instantaneous burst models. However, models of a single burst dispersed over a duration of 6 Myr fit the data well and provide the clearest evidence yet of an age gradient along the star-forming arc, with the youngest clusters nearest the north-east dust lane. The long-slit kinematics show no evidence to support previous claims of a second hidden mass concentration, although we do observe changes in molecular gas velocity consistent with the presence of a shock at the edge of the dust lane. [ABSTRACT FROM AUTHOR]

We present near-infrared (NIR) adaptive optics-assisted spectroscopic observations of the absorption bands towards the centre of the giant elliptical galaxy NGC 1399. The observations were made with NAOS-CONICA (on the European Southern Observatory's Very Large Telescope) and have a full width at half-maximum resolution of 0.15 arcsec (14 pc). Kinematic analysis of the observations reveals a decoupled core and strongly non-Gaussian line-of-sight velocity profiles in the central 0.2 arcsec (19 pc). NIR imaging also indicates an asymmetric elongation of the central isophotes in the same region. We use spherical orbit-superposition models to interpret the kinematics, using a set of orthogonal ‘eigen-velocity profiles’ that allow us to fit models directly to spectra. The models require a central black hole of mass , with a strongly tangentially biased orbit distribution in the inner 40 pc. [ABSTRACT FROM AUTHOR]

We present Herschel far-IR photometry and spectroscopy as well as ground-based CO observations of an intermediate redshift (0.21 ⩽ z ⩽ 0.88) sample of Herschel-selected (ultra)-luminous infrared galaxies (LIR > 1011.5L☼). With these measurements, we trace the dust continuum, far-IR atomic line emission, in particular [C II] 157.7 μm, as well as the molecular gas of z ∼ 0.3 luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) and perform a detailed investigation of the interstellar medium of the population. We find that the majority of Herschel-selected intermediate redshift (U)LIRGs have LC II /LFIR ratios that are a factor of about 10 higher than that of local ULIRGs and comparable to that of local normal and high-z star-forming galaxies. Using our sample to bridge local and high-z [C II] observations, we find that the majority of galaxies at all redshifts and all luminosities follow an LC II –LFIR relation with a slope of unity, from which local ULIRGs and high-z active-galactic-nucleus-dominated sources are clear outliers. We also confirm that the strong anti-correlation between the LC II /LFIR ratio and the far-IR color L60/L100 observed in the local universe holds over a broad range of redshifts and luminosities, in the sense that warmer sources exhibit lower LC II /LFIR at any epoch. Intermediate redshift ULIRGs are also characterized by large molecular gas reservoirs and by lower star formation efficiencies compared to that of local ULIRGs. The high LC II /LFIR ratios, the moderate star formation efficiencies (LIR/ or LIR/), and the relatively low dust temperatures of our sample (which are also common characteristics of high-z star-forming galaxies with ULIRG-like luminosities) indicate that the evolution of the physical properties of (U)LIRGs between the present day and z > 1 is already significant by z ∼ 0.3. [ABSTRACT FROM AUTHOR]