A Luminous Quasar at Redshift 7.642
Feige Wang, Jinyi Yang, Xiaohui Fan, Joseph F. Hennawi, Aaron J. Barth, Eduardo Banados, Fuyan Bian, Konstantina Boutsia, Thomas Connor, Frederick B. Davies, Roberto Decarli, Anna-Christina Eilers, Emanuele Paolo Farina, Richard Green, Linhua Jiang, Jiang-Tao Li, Chiara Mazzucchelli, Riccardo Nanni, Jan-Torge Schindler, Bram Venemans, Fabian Walter, Xue-Bing Wu, Minghao Yue
DDraft version January 12, 2021
Typeset using L A TEX twocolumn style in AASTeX63
A Luminous Quasar at Redshift 7.642
Feige Wang, ∗ Jinyi Yang, † Xiaohui Fan, Joseph F. Hennawi,
2, 3
Aaron J. Barth, Eduardo Banados, Fuyan Bian, Konstantina Boutsia, Thomas Connor, Frederick B. Davies,
8, 3
Roberto Decarli, Anna-Christina Eilers, ∗ Emanuele Paolo Farina, Richard Green, Linhua Jiang, Jiang-Tao Li, Chiara Mazzucchelli, Riccardo Nanni, Jan-Torge Schindler, Bram Venemans, Fabian Walter, Xue-Bing Wu,
12, 14 and Minghao Yue Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA Max Planck Institut f¨ur Astronomie, K¨onigstuhl 17, D-69117, Heidelberg, Germany Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA European Southern Observatory, Alonso de C´ordova 3107, Casilla 19001, Vitacura, Santiago 19, Chile Las Campanas Observatory, Carnegie Observatories, Colina El Pino, Casilla 601, La Serena, Chile Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, USA INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Gobetti 93/3, I-40129 Bologna, Italy MIT-Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue, Building 37, Room 664L, Cambridge,Massachusetts 02139, USA Max Planck Institut f¨ur Astrophysik, Karl–Schwarzschild–Straße 1, D-85748, Garching bei M¨unchen, Germany Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China Department of Astronomy, University of Michigan, 311 West Hall, 1085 S. University Ave, Ann Arbor, MI, 48109-1107, USA Department of Astronomy, School of Physics, Peking University, Beijing 100871, China
ABSTRACTDistant quasars are unique tracers to study the formation of the earliest supermassive black holes(SMBHs) and the history of cosmic reionization. Despite extensive efforts, only two quasars have beenfound at z ≥ .
5, due to a combination of their low spatial density and the high contamination rate inquasar selection. We report the discovery of a luminous quasar at z = 7 . − . × L (cid:12) . Deep spectroscopicobservations reveal a SMBH with a mass of (1 . ± . × M (cid:12) in this quasar. The existence of such amassive SMBH just ∼
670 million years after the Big Bang challenges significantly theoretical models ofSMBH growth. In addition, the quasar spectrum exhibits strong broad absorption line (BAL) featuresin C IV and Si IV , with a maximum velocity close to 20% of the speed of light. The relativistic BALfeatures, combined with a strongly blueshifted C IV emission line, indicate that there is a strong activegalactic nucleus (AGN) driven outflow in this system. ALMA observations detect the dust continuumand [C II ] emission from the quasar host galaxy, yielding an accurate redshift of 7 . ± . ∼
200 M (cid:12) yr − and a dust mass of ∼ × M (cid:12) . Followup observations of this reionization-eraBAL quasar will provide a powerful probe of the effects of AGN feedback on the growth of the earliestmassive galaxies. INTRODUCTIONLuminous high-redshift quasars are key probes of thehistory of cosmic reionization. Deep spectroscopy of
Corresponding author: Feige [email protected] ∗ Hubble Fellow † Strittmatter Fellow z > z (cid:38) z (cid:46) a r X i v : . [ a s t r o - ph . GA ] J a n Wang et al. tron scattering optical depth (e.g. Planck Collaborationet al. 2020).In addition, the earliest supermassive black holes(SMBHs), the engines of the most distant quasars, arecrucial for understanding the formation mechanisms ofthe first generation black hole seeds (see Inayoshi et al.2020, for a recent review). A billion solar mass SMBHat z ∼
7, having grown at the Eddington limit since for-mation, requires a seed black hole of mass ∼ M (cid:12) atthe time the first luminous object formed in the Universe(i.e., z ∼
30, Tegmark et al. 1997). This growth corre-sponds to a factor of ∼ increase in mass within amere ∼
650 Myr. The recent discovery of a 1 . × M (cid:12) SMBH in a luminous quasar at z = 7 .
52 poses the moststringent constraints yet on the masses of the seed blackholes (Yang et al. 2020a).After a decade of industrious searches, a sample ofmore than 50 quasars now exists at 6 . < z < z > α emission is redshifted to near-infrared wavelengths, making both imaging and spec-troscopic observations more challenging. In addition,the number density of z > z > z = 7 . − z = 7 . . × M (cid:12) SMBH and strong out-flows in this quasar provide new insights into the forma-tion and the growth of the earliest SMBH. Throughoutthis Letter, we use a ΛCDM cosmological model with H = 70 . − Mpc − , Ω M = 0 .
3, and Ω Λ = 0 . OBSERVATIONS AND DATA REDUCTIONJ0313–1806 was selected as a z > . Wide-field Infrared Survey Explorer sur-vey (
WISE,
Wright et al. 2010). J0313–1806 falls intoa sky area covered by PS1, DELS, VHS, and
WISE .It drops out in all of the optical bands but is well de-tected in the infrared bands (see Figure. 1) with colorsof z − J > . J − W1 = 0 .
91, and W1 − W2 = − . z -band and the blue slope ofthe continuum make it a promising quasar candidate at z > .
2. The detailed photometry for J0313–1806 islisted in Table 1 and the cutout images are shown inFigure 1. 2.1.
Near-infrared Spectroscopy
The initial spectroscopic observation for J0313–1806was obtained on 2019 November 04 (UT) with Mag-ellan/FIRE (Simcoe et al. 2010) using the high-throughput longslit mode. A 15-minute exposure showsa clear Lyman break at 1.048 µ m, indicating that it is asource at z (cid:38) .
6. We then followed this object up withMagellan/FIRE in Echelle mode and with the JH grismon Gemini/Flamingos-2 (Eikenberry et al. 2004) andconfirmed it as a high redshift quasar. Since the Mg II emission line, the most reliable line for measuring blackhole mass at high redshifts, is redshifted to the edge ofthe ground-based infrared observation window, exten-sive spectroscopic observations were obtained with Mag-ellan/FIRE (Echelle mode), Gemini/Flamingos-2 (withHK Grism), Keck/NIRES and Gemini/GNIRS (Eliaset al. 2006) to improve the S/N at this wavelength. De-tailed information for all the observations is listed inTable 1.All spectra were reduced with the spectroscopic datareduction pipeline PyPeIt (Prochaska et al. 2020a,b).The pipeline includes flat fielding, wavelength calibra-tion, sky subtraction, optimal extraction, flux calibra-tion and telluric correction. More detailed descriptionsof each processing step can be found in Prochaska et al.(2020b) and Wang et al. (2020a). We stacked all spec-tra obtained from FIRE (Echelle mode), Flamingos-2(with the HK Grism), NIRES and GNIRS after binningthem to a common wavelength grid with a pixel size of ∼
86 km s − (similar to the GNIRS native pixel scale).We then scaled the stacked spectrum by carrying outsynthetic photometry on the spectrum using the VISTA J -band filter response curve to match the J -band pho-tometry for absolute flux calibration. The final spec-trum after correcting for Galactic extinction based on https://github.com/pypeit/PypeIt Luminous Quasar at z = 7 .
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Figure 1.
Upper panel: image cutouts (20 (cid:48)(cid:48) × (cid:48)(cid:48) , north is up and east is to the left) for J0313–1806 in PS1 z , PS1 y ,DELS z , VISTA J , VISTA K s, WISE W1 and WISE W2 bands. The photometry is given in Table 1. Lower panel: the finalstacked spectrum of J0313–1806. In the figure, we re-binned the spectrum by two spectral pixels ( ∼
173 km s − ) for illustrationpurposes. The black and gray lines represent the Galactic extinction-corrected spectrum and the error vector, respectively. Theblue line denotes the quasar composite spectrum constructed with SDSS z ∼ IV blueshifts and linestrengths. The purple dashed line denotes the power-law continuum. The orange points are flux densities determined fromphotometry in the J and K s-bands. The inset panel shows the Mg II line fitting with the purple dot-dashed line denotingthe power-law continuum, the green dashed line denoting the pseudo-continuum model (the sum of power law continuum, Fe II emission, and Balmer continuum), the orange line representing the Gaussian fitting of the Mg II line and the red line representingthe total fit of pseudo-continuum and Mg II line. The thin grey lines in the insert panel represent the spectral fitting of 100mock spectra as described in § the dust map of Schlegel et al. (1998) and extinctionlaw of Cardelli et al. (1989) is shown in Figure 1.2.2. ALMA Observations
In order to determine the systemic redshift and inves-tigate the host galaxy properties, we observed J0313–1806 with the Atacama Large Millimeter/submillimeterArray (ALMA) in the C43-4 configuration (program ID:2019.A.00017.S, PI: F. Wang). We tuned two spectralwindows centered at the expected frequency of the [C II ]line and the other two spectral windows centered atabout 15 GHz away from the expected [C II ] line. Theobservations were taken in 2020 March 02 with 29 min-utes of on-source integration time.The ALMA data were reduced using the CASA 5.6.1pipeline (McMullin et al. 2007) following the standardcalibration procedures. The continuum map was im-aged by averaging over all the line-free channels usingBriggs cleaning via the CASA task tclean with robust- ness parameter r = 2 .
0, corresponding to natural visibil-ity weights, to maximize the signal-to-noise ratio (S/N)of our observations. The beam size for the continuumimage is 0 . (cid:48)(cid:48) × . (cid:48)(cid:48)
56. We subtracted the continuum us-ing the uvcontsub before imaging the [C II ] line. The[C II ] map was collapsed over ± . σ line to maximizethe S/N of the intensity map. Since both the contin-uum and [C II ] emissions are marginally resolved, weextracted the 1D spectrum with an 1 . (cid:48)(cid:48) II ] map and [C II ]+continuum spectrumare shown in Figure 2. From the spectral fitting of the[C II ]+continuum spectrum, we derive a [C II ] redshiftof z [CII] = 7 . ± . A 1.6 BILLION SOLAR MASS BLACK HOLEThe most reliable tool for measuring the mass ofSMBHs at high redshift is the Mg II virial estimator(Vestergaard & Osmer 2009). We first de-redshift the Wang et al. − ∆RA (kpc) − ∆ D E C ( k p c ) Continuum map − ∆RA (kpc) − ∆ D E C ( k p c ) [C ii ] map . . . . . . . . Observed frequency [GHz] F ν [ m J y ] [C ii ] spectrum0 . . . m J y b e a m − − . . . J yk m s − b e a m − Figure 2.
ALMA observations of the dust continuum and [C II ] line. The left panel shows the dust continuum map withcontour levels of [3, 5, 7, 9, 11, 13] × σ , where σ = 0 .
02 mJy. The middle panel shows the integrated [C II ] emission with contourlevels of [3, 4] × σ , where σ = 0 .
04 Jy km s − . The sizes of the continuum cutout and the [C II ] cutout are 4 (cid:48)(cid:48) × (cid:48)(cid:48) . The [C II ]intensity map was collapsed over ± . σ line . The white crosses in both the left and middle panels highlight the quasar positionderived from VHS infrared images. The right panel shows the [C II ] spectrum (black) and noise vector (blue) extracted from thedata cube with an aperture diameter of 1 . (cid:48)(cid:48) ∼
30 km s − ). The spectral fitting (red line) gives FWHM = 312 ±
94 km s − and z [CII] = 7 . ± . spectrum to the rest-frame using the [C II ] redshift.Then we fit a pseudo-continuum model that containsa power-law continuum, Fe II emission (Vestergaard &Wilkes 2001; Tsuzuki et al. 2006) and a Balmer contin-uum (De Rosa et al. 2014) to spectral regions free ofstrong, broad emission/absorption lines (except for theFe II ). This procedure allows us to measure a rest-frameUV slope of α λ = − . ± .
02 and a quasar bolometricluminosity of (1 . ± . × erg s − after applying abolometric correction factor of C = 5 .
15 (Shen et al.2011). After subtracting the pseudo-continuum modelfrom the spectrum, we fit a two-Gaussian model to theMg II line and derive a full width at half maximum ofFWHM = 3670 ±
405 km s − and a Mg II -based redshiftof z MgII = 7 . ± . II virial estimator of Vestergaard & Osmer(2009), we estimate the mass of the central SMBH tobe M BH = (1 . ± . × M (cid:12) . The Eddington ratioof this SMBH is L bol /L Edd = 0 . ± .
14, which indi-cates that the quasar is in a rapidly accreting phase,similar to other luminous quasars known at z > σ error. All the measure-ments and corresponding uncertainties from the spectralfitting are listed in Table 1.In Figure 1, we also show the individual fittings of the100 mock spectra. Note that our best-fit model slightlyover-estimates the flux in the ranges of 22800–23400 ˚Aand 24400–25000˚A. In order to explore the effects of the continuum overestimation on M BH measurements,we re-fit the spectrum in K-band only and estimateFWHM MgII = 4108 ±
473 km s − and M BH = (1 . ± . × M (cid:12) , consistent with that derived from theglobal fitting within uncertainties. This K -band spec-tral model gives a better fit over this wavelength range,but extrapolating it to the J and H bands shows thatit overestimates the continuum at wavelengths shorterthan K , suggesting that the quasar could be slightly red-dened by dust and cannot be well modeled with a singlepower law. In addition, the fitting could also be affectedby the difference between the iron template and the ironemission from this particular quasar, the possible Mg II absorption from outflowing gas and/or intervening metalabsorbers (see § µ m are needed tocharacterize the dust extinction and to better constrainthe M BH . In this work, we adopt the best fit from theglobal fitting as our fiducial model.To compare the constraints of seed black hole massesand the growth history of the earliest SMBHs from z > z > M BH measurements in Figure 3 by as-suming an Eddington accretion with a 10% radiativeefficiency and a duty cycle of unity. In this figure,all M BH were measured using the same Mg II virialestimator (Vestergaard & Osmer 2009) and thus havethe same systematic uncertainties ( ∼ . z >
7, poses the most challeng-ing constraint on the seed black hole mass. AssumingEddington-limited accretion, if the SMBH started itsgrowth at redshift z ∼ −
30 (i.e., ∼ −
570 Myrgrowth time), it requires a 10 − M (cid:12) seed black hole;such a seed is inconsistent with being a Population III Luminous Quasar at z = 7 .
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Table 1.
The observational information andphysical properties of J0313–1806R.A. (J2000) 03:13:43.84Decl. (J2000) − J ± K s ± ± ± g , r , z > . > . > . a z ps1 , y ps1 > . > . a M − ± z [CII] ± z MgII ± z CIV ± v MgII − [CII] ±
140 km s − ∆ v CIV − MgII ±
332 km s − FWHM
MgII ±
405 km s − α λ − ± λL ˚ A (2.7 ± × erg s − L bol (1.4 ± × erg s − M BH (1.6 ± × M (cid:12) L bol /L Edd ± [CII] ±
94 km s − F [CII] ± − L [CII] (0.80 ± × L (cid:12) S . ± L TIR (1.5 ± × L (cid:12) M dust ∼ × M (cid:12) SFR [CII] − M (cid:12) yr − SFR
TIR ± M (cid:12) yr − t exp , ALMA
29 min t exp , FIRE , Longslit
15 min t exp , Flamingos , JH
30 min t exp , FIRE , Echelle
362 min t exp , Flamingos , HK
184 min t exp , GNIRS
485 min t exp , NIRES
264 min a In these undetected bands, we report the 2 σ limiting magnitudes measured from a 3 . (cid:48)(cid:48) star remnant (e.g. Madau & Rees 2001) or the product ofdynamical processes in dense star clusters (e.g. PortegiesZwart et al. 2004). Instead, direct-collapse black holes(DCBH) forming in pre-galactic dark matter halos (e.g.Begelman et al. 2006) is the preferred seeding scenario. Redshift M B H [ M (cid:12) ] Remnant of Pop III starDense star clusterDCBH
J0252 − z = 7 . − z = 7 . z = 7 . z = 7 . z = 7 . z = 7 . − z = 7 . Time since Big Bang (Gyr)
Figure 3.
Black hole growth track of z ≥ z > EXTREMELY HIGH VELOCITY OUTFLOWAnother notable feature of J0313–1806 is that thespectrum contains several broad absorption line (BAL)features. The BAL features are thought to be producedby strong outflows launched from the accretion disk ofthe accreting SMBH. In Figure 4, we show the normal-ized spectra in the velocity space of the Si IV , C IV , andMg II emission lines. The composite spectrum (blue linein Figure 1) that was used for normalizing the observedspectrum was constructed from the spectra of a sampleof low-redshift quasars with similar relative blueshiftsbetween C IV and Mg II lines and similar equivalentwidths of C IV to those of J0313–1806, following the al-gorithm developed by Wang et al. (2020a). It was scaledto match the observed spectrum in the observed-frame2 . − . µ m. Using the normalized spectrum shownin Figure 4, we identified two C IV absorption troughs(highlighted orange regions in the middle panel of Figure4) at extremely high velocities of (0.171–0.186) c (troughA) and (0.109–0.155) c (trough B). We use the “balnic- Wang et al. ity” index (BI; Weymann et al. 1991) to estimate thestrength of the BALs in the quasar. The measured BIsare 1300 km s − and 5400 km s − for troughs A and B,respectively. Trough B also has a Si IV absorption inthe corresponding velocity range. The associated Si IV absorption for trough A falls into the Gunn-Petersontrough and is thus undetectable. Because the potentialBAL absorptions from Si IV could clobber the proximityzone, we can not use this quasar to perform the dampingwing studies.We also considered the alternative explanation thatthe two troughs are Si IV absorption troughs (high-lighted orange regions in the top panel of Figure 4)with slightly lower velocities (i.e. < . c ). We rulethis explanation out given that there are no associatedC IV absorption troughs at the corresponding velocities.We note that there is a possible weak Mg II absorp-tion (highlighted purple regions in the bottom panelof Figure 4), which would mean that J0313–1806 is aLow-ionization BAL (LoBAL). However, the Mg II ab-sorption feature does not satisfy the BI definition (i.e.continuously smaller than 0.9 for more than 2000 kms − ). The absorption could also be affected by a mis-match of the iron emission between the composite andJ0313–1806. Foreground absorption from the interven-ing IGM and/or circumgalactic medium (CGM) couldalso contribute to some of the absorption. Future highresolution spectroscopic observations are needed to iden-tify individual foreground metal absorbers.Extremely high velocity ( > . c ) outflows are amongthe most promising evidence for active galactic nucleus(AGN) feedback, given that their kinetic power mightbe high enough to affect the star formation in quasarhost galaxies (e.g. Chartas et al. 2009). Such outflowsare also very rare phenomena at lower redshifts; for ex-ample, Rodr´ıguez Hidalgo et al. (2020) identified only40 ( ∼ . ∼ z ∼ −
5. Thus, the discovery of relativistic outflowsin J0313–1806 and J0038–1527 ( z = 7 .
03; Wang et al.2018) among a sample of only 8 z > IV broad emission line has a substantial blueshift, anothersignature of radiation driven outflows, with a velocityof 3080 km s − relative to the Mg II line and 4152 kms − relative to the [C II ] line. The substantial blueshiftof the C IV broad emission line, consistent with what isexpected from the relation between the outflow velocityand the C IV blueshift (Rankine et al. 2020), is amongthe most extreme cases observed at lower redshifts. Such Figure 4.
The normalized spectrum of J0313–1806. Thesolid and dashed lines represent 100% and 90% of the nor-malized spectrum, respectively. The top panel shows theoutflow velocity of the Si IV line, the middle panel denotesthe outflow velocity of the C IV line, and the bottom panelrepresents the outflow velocity of the Mg II line. We interpretthe two most obvious troughs (orange regions) as extremelyhigh velocity C IV outflow systems with trough A having v =(0 . − . c and trough B having v = (0 . − . c .There is a potential weak Mg II absorption trough (the high-lighted purple region in the bottom panel), but it does notsatisfy the BI definition. large blueshifts of C IV emission have also commonlybeen observed in other luminous z > . QUASAR HOST GALAXYThe dust continuum around the redshifted [C II ] emis-sion from the quasar host galaxy is significantly de-tected by ALMA (Figure 2). We measure the contin-uum flux S . = 0 . ± .
05 mJy from a two-dimensional Gaussian fit to the collapsed continuummap using the CASA task imfit . The continuum emis-sion is marginally resolved with a de-convolved size of0 . (cid:48)(cid:48) × . (cid:48)(cid:48)
29 or a physical size of 3 . × .
44 kpc, similarto the sizes of other quasar host galaxies at z (cid:38) T dust = 47 K andan emissivity index of β = 1 . Luminous Quasar at z = 7 .
642 7ground on the dust emission, we estimate a total infraredluminosity of L TIR = (1 . ± . × L (cid:12) . We estimatethe star formation rate (SFR) of the quasar host galaxyto be SFR=225 ± M (cid:12) yr − based on the scaling rela-tion between the SFR and L TIR (Murphy et al. 2011).With the same set of assumptions, we estimate a totaldust mass of ∼ × M (cid:12) following Venemans et al.(2018).The [C II ] line is also detected (with peak pixel at > σ ) in our ALMA observations as shown in Figure2. A single Gaussian fit to the [C II ] line gives z [CII] =7 . ± . [CII] = 312 ±
94 km s − . In-stead of measuring the total [C II ] line flux from the one-D spectrum, we measure it from the two-dimensionalintegrated line map using imfit following Decarli etal. (2018), and derive F [CII] = 0 . ± .
16 Jy km s − .This corresponds to a [C II ] luminosity of L [CII] =(0 . ± . × L (cid:12) and a SFR [CII] = 40 − M (cid:12) yr − by adopting the empirical relation from De Looze et al.(2014), consistent with the SFR derived from the totalinfrared luminosity. The properties of the quasar hostgalaxy are comparable to that of the other two quasarhost galaxies known at z > . III ] emis-sion with the Near-Infrared Spectrograph (NIRSpec) onJames Webb Space Telescope (JWST) will be necessaryto carry out more detailed investigations of the dynami-cal mass of the host galaxy and the impact of the quasaroutflow on star formation in the host galaxy. SUMMARYIn this letter, we report the discovery of a luminousquasar, J0313–1806, at redshift z = 7 . L bol = (1 . ± . × erg s − andhosts a SMBH with a mass of (1 . ± . × M (cid:12) ,accreting at an Eddington ratio of 0 . ± .
14. Theexistence of such a SMBH just ∼
670 million years af-ter the Big Bang puts strong constraints on the forma-tion models of seed black holes. The quasar’s rest-frameUV spectrum exhibits broad absorption troughs fromextremely high-velocity outflows. These outflows havea maximum velocity up to ∼
20% of the speed of light.We also detect strong dust emission and [C II ] line emis-sion from the host galaxy in ALMA data. The ALMAobservations suggest that J0313–1806 is hosted by anintensely star-forming galaxy with a star formation rateof ∼ M (cid:12) yr − . The continuum observations in-dicate that substantial dust ( ∼ × M (cid:12) ) was al-ready built up in the quasar host galaxy. The relativistic quasar outflow and the fast SMBH growth phase, com-bined with the intense star forming activity in the hostgalaxy, suggest that J0313–1806 is an ideal target forinvestigating the assembly of the earliest SMBHs andtheir massive host galaxies with future high resolutionALMA and JWST NIRSpec/IFU observations.ACKNOWLEDGMENTSSupport for this work was provided by NASAthrough the NASA Hubble Fellowship grant Wang et al. knowledgement: The National Radio Astronomy Ob-servatory is a facility of the National Science Founda-tion operated under cooperative agreement by Associ-ated Universities, Inc.This research is based in part on observations obtainedat the international Gemini Observatory (GS-2019B-Q-134, GN-2019B-DD-110), a program of NSF’s NOIR-Lab, which is managed by the Association of Universi-ties for Research in Astronomy (AURA) under a cooper-ative agreement with the National Science Foundation.on behalf of the Gemini Observatory partnership: theNational Science Foundation (United States), NationalResearch Council (Canada), Agencia Nacional de Inves-tigaci´on y Desarrollo (Chile), Ministerio de Ciencia, Tec-nolog´ıa e Innovaci´on (Argentina), Minist´erio da Ciˆencia,Tecnologia, Inova¸c˜oes e Comunica¸c˜oes (Brazil), and Ko-rea Astronomy and Space Science Institute (Republic ofKorea).Some of the data presented in this paper were obtainedat the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute ofTechnology, the University of California, and the Na-tional Aeronautics and Space Administration. The Ob-servatory was made possible by the generous financialsupport of the W. M. Keck Foundation. The authorswish to recognize and acknowledge the very significantcultural role and reverence that the summit of Mau-nakea has always had within the indigenous Hawaiiancommunity.This paper includes data gathered with the 6.5 meterMagellan Telescopes located at Las Campanas Observa-tory, Chile.
Facilities:
ALMA, Magellan (FIRE), Gemini(FLAMINGOS-2), Gemini (GNIRS), Keck (NIRES)
Software:
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Luminous Quasar at z = 7 .
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