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Massive galaxies in the early Universe host supermassive black holes at their centers. When material falls toward the black hole, it releases energy and is observed as a quasar. Astronomers found a population of powerful distant quasars that are obscured by dust, but it has been unclear how they are formed. Díaz-Santos et al. observed the dust-obscured quasar WISE J224607.56-052634.9 at submillimeter wavelengths, finding three small companion galaxies connected to the quasar by bridges of gas and dust. They inferred that galaxy mergers can provide both the raw material to power a quasar and large quantities of dust to obscure it. Science , this issue p. 1034 Galaxy mergers can provide the raw materials to drive powerful dust-observed quasars in the early Universe. Galaxy mergers and gas accretion from the cosmic web drove the growth of galaxies and their central black holes at early epochs. We report spectroscopic imaging of a multiple merger event in the most luminous known galaxy, WISE J224607.56−052634.9 (W2246−0526), a dust-obscured quasar at redshift 4.6, 1.3 billion years after the Big Bang. Far-infrared dust continuum observations show three galaxy companions around W2246−0526 with disturbed morphologies, connected by streams of dust likely produced by the dynamical interaction. The detection of tidal dusty bridges shows that W2246−0526 is accreting its neighbors, suggesting that merger activity may be a dominant mechanism through which the most luminous galaxies simultaneously obscure and feed their central supermassive black holes.

We present new X-ray observations of luminous heavily dust-reddened quasars (HRQs) selected from infrared sky surveys. HRQs appear to be a dominant population at high redshifts and the highest luminosities, and may be associated with a transitional \"blowout\" phase of black hole and galaxy co-evolution models. Despite this, their high-energy properties have been poorly known. We use the overall sample of \\(10\\) objects with XMM-Newton coverage to study the high-energy properties of HRQs at \\(\\left< L_{\\rm bol} \\right> = 10^{47.5}\\) erg/s and \\(\\left< z \\right>= 2.5\\). For the seven sources with strong X-ray detections, we perform spectral analyses. These find a median X-ray luminosity of \\(\\left< L_{\\rm 2-10\\,keV} \\right> = 10^{45.1}\\) erg/s, comparable to the most powerful X-ray quasars known. The gas column densities are \\(N_{\\rm H}=(1\\)-\\(8)\\times 10^{22}\\) cm\\(^{-2}\\), in agreement with the amount of dust extinction observed. The dust to gas ratios are sub-Galactic, but are higher than found in local AGN. The intrinsic X-ray luminosities of HRQs are weak compared to the mid-infrared (\\(L_{\\rm 6\\mu m}\\)) and bolometric luminosities (\\(L_{\\rm bol}\\)), in agreement with findings for other luminous quasar samples. For instance, the X-ray to bolometric corrections range from \\(\\kappa_{\\rm bol}\\approx 50\\)-\\(3000\\). The moderate absorption levels and accretion rates close to the Eddington limit (\\(\\left< \\lambda_{\\rm Edd} \\right>=1.06\\)) are in agreement with a quasar blowout phase. Indeed, we find that the HRQs lie in the forbidden region of the \\(N_{\\rm H}\\)-\\(\\lambda_{\\rm Edd}\\) plane, and therefore that radiation pressure feedback on the dusty interstellar medium may be driving a phase of blowout that has been ongoing for a few \\(10^{5}\\) years. The wider properties, including [OIII] narrow-line region kinematics, broadly agree with this interpretation.

We present a study of a luminous, z=0.15, type-2 quasar (log [L([OIII])/(erg/s)]=42.8) from the Quasar Feedback Survey. It is classified as 'radio-quiet' (log [L(1.4 GHz)/(W/Hz)]=23.8); however, radio imaging reveals ~1 kpc low-power jets (log [Pjet/(erg/s)]=44) inclined into the plane of the galaxy disk. We combine MUSE and ALMA observations to map stellar kinematics and ionised and molecular gas properties. The jets are seen to drive galaxy-wide bi-conical turbulent outflows, reaching W80 = 1000-1300 km/s, in the ionised phase (traced via optical emission-lines), which also have increased electron densities compared to the quiescent gas. The turbulent gas is driven perpendicular to the jet axis and is escaping along the galaxy minor axis, reaching 7.5 kpc on both sides. Traced via CO(3-2) emission, the turbulent material in molecular gas phase is one-third as spatially extended and has 3 times lower velocity-dispersion as compared to ionised gas. The jets are seen to be strongly interacting with the interstellar medium (ISM) through enhanced ionised emission and disturbed/depleted molecular gas at the jet termini. We see further evidence for jet-induced feedback through significantly higher stellar velocity-dispersion aligned, and co-spatial with, the jet axis (<5 deg). We discuss possible negative and positive feedback scenarios arising due to the interaction of the low-power jets with the ISM in the context of recent jet-ISM interaction simulations, which qualitatively agree with our observations. We discuss how jet-induced feedback could be an important feedback mechanism even in bolometrically luminous 'radio-quiet' quasars.

We report on the discovery of a new, transient ultraluminous X-ray source (ULX) in the galaxy NGC 7090. This new ULX, which we refer to as NGC 7090 ULX3, was discovered via monitoring with \\(Swift\\) during 2019-20, and to date has exhibited a peak luminosity of \\(L_{\\rm{X}} \\sim 6 \\times 10^{39}\\) erg s\\(^{-1}\\). Archival searches show that, prior to its recent transition into the ULX regime, ULX3 appeared to exhibit a fairly stable luminosity of \\(L_{\\rm{X}} \\sim 10^{38}\\) erg s\\(^{-1}\\). Such strong long-timescale variability may be reminiscent of the small population of known ULX pulsars, although deep follow-up observations with \\(XMM\\)-\\(Newton\\) and \\(NuSTAR\\) do not reveal any robust X-ray pulsation signals. Pulsations similar to those seen from known ULX pulsars cannot be completely excluded, however, as the limit on the pulsed fraction of any signal that remains undetected in these data is \\(\\lesssim\\)20\\%. The broadband spectrum from these observations is well modelled with a simple thin disc model, consistent with sub-Eddington accretion, which may instead imply a moderately large black hole accretor (\\(M_{\\rm{BH}} \\sim 40 ~ M_{\\odot}\\)). Similarly, though, more complex models consistent with the super-Eddington spectra seen in other ULXs (and the known ULX pulsars) cannot be excluded given the limited signal-to-noise of the available broadband data. The nature of the accretor powering this new ULX therefore remains uncertain.

We use a sample of powerful z~0.1 type 2 quasars ('obscured'; log[L(AGN)/erg/s]>~45), which host kiloparsec-scale ionized outflows and jets, to identify possible signatures of AGN feedback on the total molecular gas reservoirs of their host galaxies. Specifically, we present Atacama Pathfinder EXperiment (APEX) observations of the CO(2-1) transition for nine sources and the CO(6-5) for a subset of three. We find that the majority of our sample reside in starburst galaxies (average specific star formation rates of 1.7/Gyr), with the seven CO-detected quasars also having large molecular gas reservoirs (average Mgas = 1.3x10^10Msun), even though we had no pre-selection on the star formation or molecular gas properties. Despite the presence of quasars and outflows, we find that the molecular gas fractions (Mgas/Mstar = 0.1-1.2) and depletion times (Mgas/SFR = 0.16-0.95Gyr) are consistent with those expected for the overall galaxy population with matched stellar masses and specific star formation rates. Furthermore, for at least two of the three targets with the required measurements, the CO(6-5)/CO(2-1) emission-line ratios are consistent with star formation dominating the CO excitation over this range of transitions. The targets in our study represent a gas-rich phase of galaxy evolution with simultaneously high levels of star formation and nuclear activity; furthermore, the jets and outflows do not have an immediate appreciable impact on the global molecular gas reservoirs.

Motivated by the recent discoveries that six Ultraluminous X-ray Sources (ULXs) are powered by highly super-Eddington X-ray pulsars, we searched for additional pulsating ULX (PULX) candidates by identifying sources that exhibit long-term flux variability of at least an order of magnitude (a common feature seen in the 6 known PULXs, which may potentially be related to transitions to the propeller regime). Expanding on previous studies, we used the available fluxes from XMM-Newton, Swift and Chandra, along with carefully computed upper limits in cases of a non-detection, to construct long-term lightcurves for a sample of 296 ULXs selected from the XMM-Newton archive. Among these 296, we find 25 sources showing flux variability larger than a factor of 10, of which 17 show some evidence for (or are at least consistent with) exhibiting bi-modal flux distributions, as would be expected for sources undergoing propeller transitions. These sources are excellent candidates for continued monitoring programs to further test for this behaviour. There are 3 sources in our final sample with fluxes similar to NGC 5907 ULX1, currently the faintest known PULX, which would also be good targets for deeper observations with current facilities to search for pulsations. For the rest of the PULX candidates identified here, the next generation of X-ray telescopes (such as Athena) may be required to determine their nature owing to their lower peak fluxes.

We present the first results from the Quasar Feedback Survey, a sample of 42 z<0.2, [O III] luminous AGN (L[O III]>10^42.1 ergs/s) with moderate radio luminosities (i.e. L(1.4GHz)>10^23.4 W/Hz; median L(1.4GHz)=5.9x10^23 W/Hz). Using high spatial resolution (~0.3-1 arcsec), 1.5-6 GHz radio images from the Very Large Array, we find that 67 percent of the sample have spatially extended radio features, on ~1-60 kpc scales. The radio sizes and morphologies suggest that these may be lower radio luminosity versions of compact, radio-loud AGN. By combining the radio-to-infrared excess parameter, spectral index, radio morphology and brightness temperature, we find radio emission in at least 57 percent of the sample that is associated with AGN-related processes (e.g. jets, quasar-driven winds or coronal emission). This is despite only 9.5-21 percent being classified as radio-loud using traditional criteria. The origin of the radio emission in the remainder of the sample is unclear. We find that both the established anti-correlation between radio size and the width of the [O III] line, and the known trend for the most [O III] luminous AGN to be associated with spatially-extended radio emission, also hold for our sample of moderate radio luminosity quasars. These observations add to the growing evidence of a connection between the radio emission and ionised gas in quasar host galaxies. This work lays the foundation for deeper investigations into the drivers and impact of feedback in this unique sample.

We present the X-ray properties of the 'Teacup AGN' (SDSS J1430+1339), a \\(z=0.085\\) type 2 quasar which is interacting dramatically with its host galaxy. Spectral modelling of the central quasar reveals a powerful, highly obscured AGN with a column density of \\(N_{\\rm H}=(4.2\\)-\\(6.5)\\times 10^{23}\\) cm\\(^{-2}\\) and an intrinsic luminosity of \\(L_{\\rm 2\\mbox{-}10\\,keV}=(0.8\\)-\\(1.4)\\times 10^{44}\\) erg s\\(^{-1}\\). The current high bolometric luminosity inferred (\\(L_{\\rm bol}\\approx 10^{45}\\)-\\(10^{46}\\) erg s\\(^{-1}\\)) has ramifications for previous interpretations of the Teacup as a fading/dying quasar. High resolution Chandra imaging data reveal a \\(\\approx 10\\) kpc loop of X-ray emission, co-spatial with the 'eastern bubble' previously identified in luminous radio and ionised gas (e.g., [OIII] line) emission. The X-ray emission from this structure is in good agreement with a shocked thermal gas, with \\(T=(4\\)-\\(8)\\times 10^{6}\\) K, and there is evidence for an additional hot component with \\(T\\gtrsim 3\\times 10^{7}\\) K. Although the Teacup is a radiatively dominated AGN, the estimated ratio between the bubble power and the X-ray luminosity is in remarkable agreement with observations of ellipticals, groups, and clusters of galaxies undergoing AGN feedback.

We present the results and the source catalog of the NuSTAR survey in the UKIDSS Ultra Deep Survey (UDS) field, bridging the gap in depth and area between NuSTAR's ECDFS and COSMOS surveys. The survey covers a \\(\\sim 0.6\\) deg\\(^2\\) area of the field for a total observing time of \\(\\sim\\) 1.75 Ms, to a half-area depth of \\(\\sim\\) 155 ks corrected for vignetting at \\(3-24\\) keV, and reaching sensitivity limits at half-area in the full (\\(3-24\\) keV), soft (\\(3-8\\) keV) and hard (\\(8-24\\) keV) bands of \\(2.2 \\times 10^{-14}\\) erg cm\\(^{-2}\\) s\\(^{-1}\\), \\(1.0 \\times 10^{-14}\\) erg cm\\(^{-2}\\) s\\(^{-1}\\), and \\(2.7 \\times 10^{-14}\\) erg cm\\(^{-2}\\) s\\(^{-1}\\), respectively. A total of 67 sources are detected in at least one of the three bands, 56 of which have a robust optical redshift with a median of \\(\\langle z\\rangle \\sim 1.1\\). Through a broadband (\\(0.5-24\\) keV) spectral analysis of the whole sample combined with the NuSTAR hardness ratios, we compute the observed Compton-thick (CT; \\(N_{\\rm H} > 10^{24}\\) cm\\(^{-2}\\)) fraction. Taking into account the uncertainties on each \\(N_{\\rm H}\\) measurement, the final number of CT sources is \\(6.8\\pm1.2\\). This corresponds to an observed CT fraction of \\((11.5\\pm2.0)\\%\\), providing a robust lower limit to the intrinsic fraction of CT AGN and placing constraints on cosmic X-ray background synthesis models.

We present a study of the average X-ray spectral properties of the sources detected by the NuSTAR extragalactic survey, comprising observations of the E-CDFS, EGS and COSMOS fields. The sample includes 182 NuSTAR sources (64 detected at 8-24 keV), with 3-24 keV fluxes ranging between \\(f_{\\rm 3-24 keV}\\approx10^{-14}\\) and \\(6\\times10^{-13}\\) erg/cm\\(^2\\)/s (\\(f_{\\rm 8-24 keV}\\approx3\\times10^{-14}-3\\times10^{-13}\\) erg/cm\\(^2\\)/s) and redshifts of \\(z=0.04-3.21\\). We produce composite spectra from the Chandra+NuSTAR data (\\(E\\approx2-40\\) keV, rest frame) for all the sources with redshift identifications (95%) and investigate the intrinsic, average spectra of the sources, divided into broad-line (BL) and narrow-line (NL) AGN, and also in different bins of X-ray column density and luminosity. The average power-law photon index for the whole sample is \\(\\Gamma=1.65_{-0.03}^{+0.03}\\), flatter than \\(\\Gamma\\approx1.8\\) typically found for AGN. While the spectral slope of BL and X-ray unabsorbed AGN is consistent with typical values (\\(\\Gamma=1.79_{-0.01}^{+0.01}\\)), a significant flattening is seen in NL AGN and heavily-absorbed sources (\\(\\Gamma=1.60_{-0.05}^{+0.08}\\) and \\(\\Gamma=1.38_{-0.12}^{+0.12}\\), respectively), likely due to the effect of absorption and to the contribution from Compton reflection to the high-energy flux (E>10 keV). We find that the typical reflection fraction in our spectra is \\(R\\approx0.5\\) (for \\(\\Gamma=1.8\\)), with a tentative indication of an increase of the reflection strength with column density. While there is no significant evidence for a dependence of the photon index with X-ray luminosity in our sample, we find that \\(R\\) decreases with luminosity, with relatively high levels of reflection (\\(R\\approx1.2\\)) for \\(L_{\\rm 10-40 keV}<10^{44}\\) erg/s and \\(R\\approx0.3\\) for \\(L_{\\rm 10-40 keV}>10^{44}\\) erg/s AGN, assuming \\(\\Gamma=1.8\\).