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We present the first systematic study of the molecular gas and star formation efficiency in a sample of ten narrow-line Seyfert 1 galaxies selected to have X-ray Ultra Fast Outflows and, therefore, to potentially show AGN feedback effects. CO observations were obtained with the IRAM 30-m telescope in six galaxies and from the literature for four galaxies. We derived the stellar mass, star formation rate, AGN, and FIR dust luminosities by fitting the multi-band spectral energy distributions with the CIGALE code. Most of the galaxies in our sample lie above the main sequence (MS), and the molecular depletion time is one to two orders of magnitude shorter than the one typically measured in local star-forming galaxies. Moreover, we found a promising correlation between the star formation efficiency and the Eddington ratio, as well as a tentative correlation with the AGN luminosity. The role played by the AGN activity in the regulation of star formation within the host galaxies of our sample remains uncertain (little or no effect? positive feedback?). Nevertheless, we can conclude that quenching by the AGN activity is minor and that star formation will likely stop in a short time due to gas exhaustion by the current starburst episode. [ABSTRACT FROM AUTHOR]

The final phase of the reionization process can be probed by rest-frame UV absorption spectra of quasars at z ≳ 6, shedding light on the properties of the diffuse intergalactic medium within the first Gyr of the Universe. The ESO Large Programme 'XQR-30: the ultimate XSHOOTER legacy survey of quasars at z ≃ 5.8–6.6' dedicated ∼250 h of observations at the VLT to create a homogeneous and high-quality sample of spectra of 30 luminous quasars at z ∼ 6, covering the rest wavelength range from the Lyman limit to beyond the Mg  ii emission. Twelve quasar spectra of similar quality from the XSHOOTER archive were added to form the enlarged XQR-30 sample, corresponding to a total of ∼350 h of on-source exposure time. The median effective resolving power of the 42 spectra is R ≃ 11 400 and 9800 in the VIS and NIR arm, respectively. The signal-to-noise ratio per 10 km s−1 pixel ranges from ∼11 to 114 at λ ≃ 1285 Å rest frame, with a median value of ∼29. We describe the observations, data reduction, and analysis of the spectra, together with some first results based on the E-XQR-30 sample. New photometry in the H and K bands are provided for the XQR-30 quasars, together with composite spectra whose characteristics reflect the large absolute magnitudes of the sample. The composite and the reduced spectra are released to the community through a public repository, and will enable a range of studies addressing outstanding questions regarding the first Gyr of the Universe. [ABSTRACT FROM AUTHOR]

The Narrow Line Seyfert 1 Galaxy IRAS17020+4544 is one of the few active galactic nuclei (AGNs) where a galaxy-scale energy-conserving outflow was revealed. This paper reports on NOEMA observations addressed to constrain the spatial scale of the CO emission in outflow. The molecular outflowing gas is resolved in five components tracing approaching and receding gas, all located at a distance of 2–3 kpc on the west and east sides of the active nucleus. This high-velocity gas (up to vout = ±1900 km s−1) is not coincident with the rotation pattern of the CO gas in the host galaxy disc. The estimated mass outflow rate shows that with a global mass output of |$\dot{M}_{H_2}$| = 139 |$\pm 20~\, \mathrm{M}_\odot$|  yr−1, this powerful galaxy-scale outflow is consistent with the wind conserving its energy, and with a momentum rate boost of a factor of ∼30 compared to the momentum rate of the nuclear X-ray wind. Preliminary results from ancillary X-ray (Chandra) and radio images (e-MERLIN) are reported. While the nature of the radio source is not conclusive, the Chandra image may tentatively trace extended emission, as expected by an expanding bubble of hot X-ray gas. The outcome of the NOEMA analysis and of the past and ongoing publications dedicated to the description of the outflow multiband phenomenology in IRAS17020+4544 concur to provide compelling reasons to postulate that an outflow shocking with the galaxy interstellar medium is driving the multiphase wind in this peculiar AGN. [ABSTRACT FROM AUTHOR]

The narrow-line Seyfert 1 galaxy IRAS 17020+4544 is one of the few sources where both an X-ray ultrafast outflow and a molecular outflow were observed to be consistent with energy conservation. However, IRAS 17020+4544 is less massive and has a much more modest active galactic nucleus (AGN) luminosity than the other examples. Using recent CO(1–0) observations with the NOrthern Extended Millimeter Array, we characterized the molecular gas content of the host galaxy for the first time. We found that the molecular gas is distributed into an apparent central disc of 1.1 × 109 M⊙, and a northern extension located up to 8 kpc from the centre with a molecular gas mass |$M_{\mathrm{ H}_2}\sim 10^8\, \mathrm{ M}_\odot$|⁠. The molecular gas mass and the CO dynamics in the northern extension reveal that IRAS 17020+4544 is not a standard spiral galaxy, instead it is interacting with a dwarf object corresponding to the northern extension. This interaction possibly triggers the high accretion rate on to the supermassive black hole. Within the main galaxy, which hosts the AGN, a simple analytical model predicts that the molecular gas may lie in a ring, with less molecular gas in the nuclear region. Such distribution may be the result of the AGN activity that removes or photodissociates the molecular gas in the nuclear region (AGN feedback). Finally, we have detected a molecular outflow of mass |$M_{\mathrm{ H}_2}=(0.7\!-\!1.2)\times 10^7\, \mathrm{ M}_\odot$| in projection at the location of the northern galaxy, with a similar velocity to that of the massive outflow reported in previous millimetre data obtained by the Large Millimeter Telescope. [ABSTRACT FROM AUTHOR]

We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of eight highly excited CO (⁠|${\rm J_{\rm up}}$|  > 8) lines and continuum emission in two z  ∼ 6 quasars: SDSS J231038.88+185519.7 (hereafter J2310), for which CO(8–7), CO(9–8), and CO(17–16) lines have been observed, and ULAS J131911.29+095951.4 (J1319), observed in the CO(14–13), CO(17–16), and CO(19–18) lines. The continuum emission of both quasars arises from a compact region (<0.9 kpc). By assuming a modified blackbody law, we estimate dust masses of log(M dust/M⊙) = 8.75 ± 0.07 and log(M dust/M⊙) = 8.8 ± 0.2 and dust temperatures of T dust = 76 ± 3 K and |$T_{\rm dust}=66^{+15}_{-10}\,{\rm K}$|⁠ , respectively, for J2310 and J1319. Only CO(8–7) and CO(9–8) in J2310 are detected, while 3σ upper limits on luminosities are reported for the other lines of both quasars. The CO line luminosities and upper limits measured in J2310 and J1319 are consistent with those observed in local active galactic nuclei and starburst galaxies, and other z  ∼ 6 quasars, except for SDSS J1148+5251 (J1148), the only quasar at z  = 6.4 with a previous CO(17–16) line detection. By computing the CO spectral line energy distributions normalized to the CO(6–5) line and far-infrared luminosities for J2310, J1319, and J1148, we conclude that different gas heating mechanisms (X-ray radiation and/or shocks) may explain the different CO luminosities observed in these z  ∼ 6 quasar. Future |${\rm J_{\rm up}}$|  > 8 CO observations will be crucial to understand the processes responsible for molecular gas excitation in luminous high- z quasars. [ABSTRACT FROM AUTHOR]

We report the detection of the CO(3-2) emission line from the host galaxy of gamma-ray burst (GRB) 080207 at z=2.086. This is the first detection of molecular gas in emission from a GRB host galaxy beyond redshift 1. We find this galaxy to be rich in molecular gas with a mass of 1.1 x 1011 M⊙ assuming αCO = 4.36 M⊙ (K km s-1 pc²)-1. The molecular gas mass fraction of the galaxy is ~0.5, typical of star-forming galaxies (SFGs) with similar stellar masses and redshifts. With an SFRFIR of 260 M⊙ yr-1, we measure a molecular gas depletion time-scale of 0.43 Gyr, near the peak of the depletion time-scale distribution of SFGs at similar redshifts. Our findings are therefore in contradiction with the proposed molecular gas deficiency in GRB host galaxies. We argue that the reported molecular gas deficiency for GRB hosts could be the artefact of improper comparisons or neglecting the effect of the typical low metallicities of GRB hosts on the CO-to-molecular-gas conversion factor. We also compare the kinematics of the CO(3-2) emission line to that of the Hα emission line from the host galaxy. We find the Hα emission to have contributions from two separate components, a narrow and a broad one. The narrow component matches the CO emission well in velocity space. The broad component, with a full width at half-maximum of ~1100 km s-1, is separated by +390 km s-1 in velocity space from the narrow component. We speculate this broad component to be associated with a powerful outflow in the host galaxy or in an interacting system. [ABSTRACT FROM AUTHOR]

We present the first attempt to detect outflows from galaxies approaching the Epoch of Reionization (EoR) using a sample of nine star-forming (SFR = 31 ± 20M⊚ yr-1) z ∼ 5.5 galaxies for which the [C II]158 μm line has been previously obtained with Atacama Large Millimeter Array (ALMA). We first fit each line with a Gaussian function and compute the residuals by subtracting the best-fitting model from the data. We combine the residuals of all sample galaxies and find that the total signal is characterized by a flux excess of ∼0.5mJy extended over ∼1000 km s-1. Although we cannot exclude that part of this signal is due to emission from faint satellite galaxies, we show that the most probable explanation for the detected flux excess is the presence of broad wings in the [CII] lines, signatures of starburst-driven outflows. We infer an average outflow rate of M = 54 ± 23M⊚ yr-1, providing a loading factor η = M˙ /SFR = 1.7 ± 1.3 in agreement with observed local starbursts. Our interpretation is consistent with outcomes from zoomed hydrosimulations of Dahlia, a z ∼ 6 galaxy (SFR ∼ 100M⊚ yr-1), whose feedback-regulated star formation results into an outflow rate ˙M ∼ 30M⊚ yr-1. The quality of the ALMA data is not sufficient for a detailed analysis of the [C II] line profile in individual galaxies. Nevertheless, our results suggest that starburst-driven outflows are in place in the EoR and provide useful indications for future ALMA campaigns. Deeper observations of the [CII] line in this sample are required to better characterize feedback at high-z and to understand the role of outflows in shaping early galaxy formation. [ABSTRACT FROM AUTHOR]

Similarly to the cosmic star formation history, the black hole accretion rate density of the Universe peaked at 1CO ∼ 6.3-25.1 × 109 L⊚, which translates to a molecular hydrogen gas mass of 2.5–10 × 1010M⊚ assuming conventional conversion factor of αCO ∼ 3.6. Our results indicate a >99 per cent probability of lower depletion time-scales and lower molecular gas fractions in AGN hosts with respect to the non-AGN comparison sample. We discuss the implications of these observations on the impact that AGN feedback may have on star formation efficiency of z >1 galaxies. [ABSTRACT FROM AUTHOR]

We present the 78 ks Chandra observations of the z = 6.4 quasar SDSS J1148+5251. The source is clearly detected in the energy range 0.3-7 keV with 42 counts (with a significance ≳9σ). The X-ray spectrum is best fitted by a power law with photon index Γ = 1.9 absorbed by a gas column density of NH = 2.0-1.5+2.0 x 1023 cm-2. We measure an intrinsic luminosity at 2-10 and 10-40 keV equal to ~ 1.5 x 1045 erg s-1, comparable with luminous local and intermediate-redshift quasar properties. Moreover, the X-ray to optical power-law slope value (αOX = -1.76 ± 0.14) of J1148 is consistent with the one found in quasars with similar rest-frame 2500 Å luminosity (L2500 ~ 1032 erg s-1 Å-1). Then we use Chandra data to test a physically motivated model that computes the intrinsic X-ray flux emitted by a quasar starting from the properties of the powering black hole and assuming that X-ray emission is attenuated by intervening, metal-rich (Z ≥ Z⊙) molecular clouds (MC) distributed on ~kpc scales in the host galaxy. Our analysis favours a black hole mass MBH ~ 3 x 109 M⊙ and a molecular hydrogen mass ... ~ 2 x 1010 M⊙, in good agreement with estimates obtained from previous studies. We finally discuss strengths and limits of our analysis. [ABSTRACT FROM AUTHOR]

We present ALMA observations of cold dust and molecular gas in four high-luminosity, heavily reddened (AV ~ 2.5-6 mag) type 1 quasars at z ~ 2.5 with virial MBH ~ 1010 Mʘ, to test whether dusty, massive quasars represent the evolutionary link between submillimetre-bright galaxies and unobscured quasars. All four quasars are detected in both the dust continuum and in the 12CO(3-2) line. The mean dust mass is 6 x 108 Mʘ assuming a typical high-redshift quasar spectral energy distribution (T = 41 K, β = 1.95 or T = 47 K, β = 1.6). The implied star formation rates are very high - ≳1000 Mʘ yr-1 in all cases. Gas masses estimated from the CO line luminosities cover ~1-5x 1010(αCO/0.8)Mʘ and the gas depletion time-scales are very short - ~5-20?Myr. A range of gas-to-dust ratios is observed in the sample. We resolve the molecular gas in one quasar - ULASJ2315+0143 (z = 2.561) - which shows a strong velocity gradient over ~20 kpc. The velocity field is consistent with a rotationally supported gas disc but other scenarios, e.g. mergers, cannot be ruled out at the current resolution of these data. In another quasar - ULASJ1234+0907 (z = 2.503) - we detected molecular line emission from two millimetre-bright galaxies within 200 kpc of the quasar, suggesting that this quasar resides in a significant overdensity. The high detection rate of both cold dust and molecular gas in these sources, suggests that reddened quasars could correspond to an early phase in massive galaxy formation associated with large gas reservoirs and significant star formation. [ABSTRACT FROM AUTHOR]

We explore the possibility of detecting hydrogen radio recombination lines from 0 < z < 10 quasars. We compute the expected Hna flux densities as a function of absolute magnitude and redshift by considering (i) the range of observed active galactic nucleus spectral indices from UV to X-ray bands, (ii) secondary ionizations from X-ray photons, and (iii) stimulated emission due to non-thermal radiation. All these effects are important to determine the line fluxes. We find that the combination of slopes: αX,hard = -1.11, αX,soft = -0.7, αEUV = -1.3, αUV = -1.7, maximizes the expected flux, fHnα ≈ 10 µJy for z ~ 7 quasars with MAB = -27 in the n ~ 50 lines; allowed spectral energy distribution variations produce variations by a factor of 3 around this value. Secondaries boost the line intensity by a factor of 2-4, while stimulated emission in high-z quasars with MAB ≈ -26 provides an extra boost to radio recombination line flux observed at ν ~ 1 GHz if recombinations arise in H II regions with Te ≈ 103 - 5 K, ne ≈ 103 - 5 cm-3. We compute the sensitivity required for a 5s detection of Hnα lines using the Square Kilometre Array (SKA), finding that the SKA-MID could detect sources with MAB ≲ -27 (MAB ≲ -26) at z ≲ 8 (z ≲ 3) in less than 100 h of observing time. These observations could open new paths to searches for obscured SMBH progenitors, complementing X-ray, optical/IR and sub-mm surveys. [ABSTRACT FROM AUTHOR]

Cosmic metal enrichment is one of the key physical processes regulating galaxy formation and the evolution of the intergalactic medium (IGM). However, determining the metal content of the most distant galaxies has proven so far almost impossible; also, absorption line experiments at z ≿ 6 become increasingly difficult because of instrumental limitations and the paucity of background quasars. With the advent of Atacama Large Millimeter/submillimeter Array (ALMA), far-infrared emission lines provide a novel tool to study early metal enrichment. Among these, the [CII] line at 157.74 μm is the most luminous line emitted by the interstellar medium of galaxies. It can also resonant scatter comic microwave background (CMB) photons inducing characteristic intensity fluctuations (△I/ICMB) near the peak of the CMB spectrum, thus allowing to probe the low-density IGM. We compute both [CII] galaxy emission and metal-induced CMB fluctuations at z ~ 6 by using adaptive mesh refinement cosmological hydrodynamical simulations and produce mock observations to be directly compared with ALMA Band 6 data (νobs ∼ 272 GHz). The [CII] line flux is correlated with MUV as log(Fpeak/μJy) = -27.205 - 2.253MUV - 0.038M2 UV. Such relation is in very good agreement with recent ALMA observations of MUV < -20 galaxies by e.g. Maiolino et al. and Capak et al. We predict that a MUV = -19 (MUV = -18) galaxy can be detected at 4σ in ≃40 (2000) h, respectively. CMB resonant scattering can produce ≃±0.1 μJy/beam emission/absorptions features that are very challenging to be detected with current facilities. The best strategy to detect these signals consists in the stacking of deep ALMA observations pointing fields with known MUV ≃ -19 galaxies. This would allow to simultaneously detect both [C II] emission from galactic reionization sources and CMB fluctuations produced by z ∼ 6 metals. [ABSTRACT FROM AUTHOR]

We report the results from a 2011 Suzaku observation of the nearby low-ionization broad absorption line (BAL) quasar/ULIRG Markarian 231 (Mrk 231). These data reveal that the X-ray spectrum has undergone a large variation from the 2001 XMM–Newton and BeppoSAX observations. We interpret this finding according to a scenario whereby the X-ray continuum source is obscured by a two-component partial-covering absorber with NH ∼ 1022 and ∼1024 cm−2, respectively. The observed spectral change is mostly explained by a progressive appearance of the primary continuum at <10 keV due to the decrease of the covering fraction of the denser absorption component. The properties of the X-ray obscuration in Mrk 231 match well with those of the X-ray shielding gas predicted by the theoretical models for an efficient radiatively driven acceleration of the BAL wind. In particular, the X-ray absorber might be located at the extreme base of the outflow. We measure a 2–10 keV luminosity of L2-10 = 3.3 × 1043 erg s−1 for the 2011 data set, i.e. an increase of 30 per cent with respect to the 2001 value. [ABSTRACT FROM PUBLISHER]

ABSTRACT Most theoretical models invoke quasar-driven outflows to quench star formation in massive galaxies, and this feedback mechanism is required to account for the population of old and passive galaxies observed in the local Universe. The discovery of massive, old and passive galaxies at z∼ 2 implies that such quasar feedback on to the host galaxy must have been at work very early on, close to the reionization epoch. We have observed the [C ii] 158 m transition in SDSS J114816.64+525150.3, which, at z= 6.4189, is one of the most distant quasars known. We detect broad wings of the line tracing a quasar-driven massive outflow. This is the most distant massive outflow ever detected and is likely tracing the long-sought quasar feedback, already at work in the early Universe. The outflow is marginally resolved on scales of ∼16 kpc, implying that the outflow can really affect the whole galaxy, as required by quasar feedback models. The inferred outflow rate, , is the highest ever found. At this rate, the outflow can clean the gas in the host galaxy, and therefore quench star formation, in a few million years. [ABSTRACT FROM AUTHOR]

ABSTRACT We present a long (≈76 ks) Chandra observation of IRAS 09104+4109, a hyperluminous galaxy, optically classified as a type 2 active galactic nuclei (AGN) hosted in a cD galaxy in a cluster at z= 0.442. We also report on the results obtained by fitting its broad-band spectral energy distribution. The Compton-thick nature of this source (which has been often referred to as an 'archetype' of Compton-thick type 2 quasars) was formerly claimed on the basis of its marginal detection in the Phoswich Detection System (PDS) instrument onboard BeppoSAX, being then disputed using XMM-Newton data. Both Chandra analysis and optical/mid-infrared (IR) spectral fitting are consistent with the presence of heavy (≈1-5 × 1023 cm−2), but not extreme (Compton-thick) obscuration. However, using the mid-IR and the [O iii] emission as proxies of the nuclear hard X-ray luminosity suggests the presence of heavier obscuration. The 54-month Swift BAT map shows excess hard X-ray emission likely related to a nearby ( z= 0.009) type 2 AGN, close enough to IRAS 09104+4109 to significantly enhance and contaminate its emission in the early BeppoSAX PDS data. [ABSTRACT FROM AUTHOR]