We present JWST NIRSpec IFU spectroscopic measurements of one of the faintest (M_UV>-13.6) known ionizing sources at z=5.66, dubbed Small And Lensed Source Arc, SALSA. This source is highly magnified (μ>100) by the lensing galaxy cluster Abell 2744, providing a unique opportunity to investigate the physical properties of faint sources in the Epoch of Reionization. We characterize SALSA's nebular emission using rest-frame UV and optical emission lines and investigate the relationship between its ionizing efficiency, nebular excitation, and chemical enrichment. We robustly detect Hα emission and use it to predict the Hβ flux assuming negligible dust attenuation. We also measure the [OIII]λ5007 emission and estimate oxygen abundance resulting in a high R3 index 2.82_-0.25^+0.34 and relatively low metallicity 12+log(O/H)= 7.43±0.09. SALSA presents a high ionizing production efficiency log(ξ_ion)=25.49_-0.08^+0.09 Hz erg ^-1, consistent with theoretical models from very massive stars and constant star formation rate, and a high Lyα escape fraction f_esc^Lyα=0.39±0.14. These properties place SALSA among the most extreme star-forming sources known at this epoch.

Luminous quasars at the redshift frontier z > 7 serve as stringent probes of super-massive black hole (SMBH) formation and they are thought to undergo much of their growth obscured by dense gas and dust in their host galaxies. Fully characterizing the symbiotic evolution of SMBHs and hosts requires rest-frame optical observations that span spatial scales from the broad-line region (BLR) to the interstellar and circumgalactic medium (ISM and CGM). The James Webb Space Telescope (JWST) now provides the necessary spatially resolved spectroscopy to do so. However, the physical conditions that regulate the interplay between SMBHs and their hosts at the highest redshifts, especially the nature of early feedback phases, remain unclear. We present JWST/NIRSpec integral field unit (IFU) observations of J0313-1806 at z = 7.64, the most distant luminous quasar known. From the rest-frame optical spectrum of the unresolved quasar, we derived a black hole mass of M-BH = (1.63 +/- 0.10)& times;10(9) M-circle dot based on H beta lambda 4861 (H beta) and an Eddington rate of lambda = L/L-Edd = 0.80 +/- 0.05, consistent with previous Mg II lambda 2800-based estimates. J0313-1806 exhibits no detectable [O III] lambda lambda 4959, 5007 emission on nuclear scales (3 sigma upper limit equivalent width of [O III] lambda 5007 < 1.42 & Aring;). Most remarkably, we did detect an ionized gas shell extending out to similar to 1.8 kpc traced by H beta emission that also lacks any significant [O III] lambda lambda 4959, 5007, with a 3 sigma upper limit on the [O III] lambda 5007 to H beta flux ratio of log(10)(F([O III])/F(H beta)) = -1.15. Through photoionization modeling, we demonstrate that the extended emission is consistent with a thin, clumpy outflowing shell where [O III] is collisionally de-excited by dense gas. We interpret this structure as a fossil remnant of a recent blowout phase, providing evidence for episodic feedback cycles in one of the earliest quasars. These findings suggest that dense ISM phases may play a crucial role in shaping the spectral properties of quasars across cosmic time.

We present a blind time-delay cosmography measurement of the Hubble constant H_0 based on the quadruply imaged quasar SDSSJ1433+6007. Our analysis combines deep Hubble Space Telescope imaging, extended time-delay monitoring from the Wendelstein and Maidanak Observatories, and spatially resolved stellar kinematics from the Keck Cosmic Web Imager and Reionization Mapper. We build a robust lens model to reconstruct the mass distribution and high-signal-to-noise kinematic maps to break the mass-sheet degeneracy (MSD), explicitly accounting for the lens galaxy's oblateness, rotation, and anisotropy. Furthermore, we constrain the external convergence (κ_ ext) by characterizing the line-of-sight environment using wide-field photometry from the Dark Energy Spectroscopic Instrument (DESI) Legacy Survey data release 10. We incorporate these constraints into our joint lensing and dynamical model, running multiple iterations to estimate random and systematic uncertainties. Accounting for maximal flexibility of the mass-sheet transformation, and assuming a flat ΛCDM cosmology and an Ω_ m, 0 prior from DESI data release 2, we infer H_0 = 73.2^+4.8_-4.7 km s^-1 Mpc^-1 (a 6.5% precision), and an internal mass-sheet parameter λ_ int=1.12^+0.05_-0.06. Notably, λ_ int is 2σ away from unity for this system, highlighting the importance of treating it as a free parameter. Our H_0 measurement is consistent with the result from our 2025 milestone paper, and it will be included in our next hierarchical analysis to improve the overall precision. Moving forward, the comprehensive pipeline demonstrated herein establishes a robust framework that can be readily applied to future strongly lensed systems to further refine cosmological constraints.

We present a systematic study of the environments of 25 luminous quasars at z > 6.5 from the ASPIRE program. Using JWST/NIRCam wide-field slitless spectroscopy data, we identified 487 galaxies at 5.3 less than or similar to z less than or similar to 7.0 exhibiting [O III] emission. Among these, 122 [O III] emitters lie within divided by Delta v(los)divided by < 1000 km s(-1) of the quasars, corresponding to a similar to 9.4-fold enhancement relative to the average galaxy density at other redshifts. Furthermore, we identified 16 [C II]-emitting galaxies at the quasar redshifts from Atacama Large Millimeter/submillimeter Array (ALMA) mosaic observations. A cross-correlation function analysis between quasars and [O III]+[C II] emitters yields a cross-correlation length of r(0)(QG) = 8.68 (+ 0.51)(-0.55) h(-1) cMpc and an autocorrelation of r(0)(QQ )= 15.7 6(- 2.70 )(+2.48) h(-1 )cMpc , indicating that z similar to 7 quasars reside in dark matter halos with M-halo = 10(12.27) (-0.26) (+0.21) M circle dot and have a quasar lifetime of t(Q) = 10 (7.05 )(-1.01) (+0.95 )yr . Notably, the number of [O III]-emitting galaxies at quasar redshifts varies significantly from field to field, ranging from 0 to 20, highlighting a diverse quasar environment. Remarkably, seven quasars trace significant galaxy overdensities (i.e., protoclusters), with delta(gal) > 5 within a volume of V similar to 500 cMpc(3). We also find that divided by Delta v(los)divided by increases rapidly toward smaller galaxy-quasar separations in protocluster fields, consistent with galaxy kinematics around extremely massive halos in cosmological simulations. By combining JWST and ALMA data, we reveal the complex and diverse environments of these early quasars, providing robust evidence that the earliest luminous quasars are effective tracers of galaxy overdensities, albeit with substantial field-to-field variation.

The first generation of stars, known as Population III (Pop III), formed from primordial gas consisting solely of hydrogen and helium and is believed to have emerged only a few hundred million years after the Big Bang. Detecting the chemical enrichment of metal-poor circumgalactic gas offers a promising way to trace the enrichment signature of Pop III stars. Along the sightline to the quasar SDSS J0100+2802, a metal absorber at z = 5.945, showing over-abundant carbon and silicon compared to solar, has been reported to be consistent with the enrichment pattern of Pop III stars. With the James Webb Space Telescope, we report the discovery of an unusually metal-poor galaxy overdensity of 17 members (mean metallicity ≈ 3% solar) near this metal absorber, which is ∼ 0.4 dex more metal-poor than coeval galaxies in similarly overdense environments. This less chemically evolved system may have provided favorable conditions for preserving the absorption signatures of Pop III enrichment. We infer a minimum dark matter halo of log(M_h,min/M_⊙)=10.68^+0.93_-1.72, supporting late-time Pop III formation at the outskirts of atomic hydrogen cooling halos. Our findings open a promising observational pathway to identify the chemical imprints of the first stars and constrain the conditions for their formation.

The population of bright galaxies at z≳10 discovered by JWST, including the so-called "blue monsters", has been difficult to reconcile with standard galaxy evolution models. To shed light on this extraordinary population, we study the z∼8 galaxies discovered by the BoRG-JWST survey. These slightly-lower redshift analogs are comparable in UV luminosity to the blue monsters, and their lower redshift makes it much easier to access key rest frame optical diagnostics with NIRspec. We find that BoRG-JWST galaxies are consistent with being dust-poor based on their blue UV slopes and Balmer decrement ratios. We find no strong evidence for dominant active galactic nuclei contribution to the UV brightness, based on line-ratio diagnostics, though some contribution cannot be excluded. We further infer the stellar mass, star formation and UV-brightness history of the BoRG-JWST galaxies by fitting their rest-frame UV-optical spectra. We see evidence for stochastic episodes of star formation for all the BoRG-JWST galaxies, providing a temporal boosting of UV luminosity in short timescales. The UV-bright blue monsters at z≳10 can be explained by the presence of stars with ages below 100 Myr.

We present new results on the rest-frame UV luminosity function (UVLF) and stellar mass-to-light ( M / L ) ratio of bright ( M UV ≲ −20 mag) spectroscopically confirmed galaxies at z = 7–9 derived from the BoRG-JWST survey, a unique data set of NIRSpec prism follow-up of Hubble Space Telescope (HST)–selected sources from random-pointing imaging. By selecting galaxies from over 300 independent sight lines, the survey minimizes cosmic variance, ensuring a statistically robust sample of the bright-galaxy population during the epoch of reionization. The data are used to constrain, for the first time, the bright end of the UVLF at z = 7–9 from spectroscopically confirmed galaxies over eight independent fields. We find that the bright end of the UVLF is higher than found using imaging over JWST legacy fields, suggesting that the latter may be significantly affected by cosmic variance, and thus reducing the tension with recent findings from JWST at z > 10 and comparable to models invoking little dust attenuation and bursty star formation. Additionally, we use the galaxies’ JWST spectra to infer their stellar masses and M / L ratios relative to other HST and JWST studies. We show that the stellar mass scales almost linearly with UV luminosity ( M * ∝ L UV 0.85 ± 0.12 ), albeit with large (∼0.5 dex) intrinsic scatter, consistent with stochastic bursts of star formation in early galaxy formation.

We present the first study dedicated to measuring the timescales for black hole accretion and jet launching in a quasar at the edge of reionization, PSO J352.4034–15.3373 at z = 5.832 ± 0.001. Previous work presented evidence of the strong radio synchrotron emission from the jet affecting the host galaxy's dust-dominated continuum emission at ν rest = 683 GHz ( ν obs = 100 GHz), implying a break in the synchrotron spectrum. In this work, we present quasi-simultaneous observations at 1.5 GHz–42 GHz with the Karl G. Jansky Very Large Array, and derive a frequency break at ν rest break = 196.46 GHz ( ν obs break = 28.76 GHz). Modeling these observations, we calculate the jet spectral aging from the cooling of electrons to be t spec ∼ 580 yr. From this measurement, we approximate the dynamical age t dyn to be ∼2000 yr, implying a recent jet ejection. We compare the jet timescale to the quasar’s lifetime ( t Q ) that indicates the duration of the latest black hole accretion event and is derived from the proximity zone size in the rest-UV/optical spectrum. However, a ghostly damped Ly α system affects this measurement yielding an upper limit of t Q ≲ 10 4 yr, consistent with the jet lifetime and indicative of a young quasar. This suggests that the triggering of a UV-bright quasar phase may occur within comparable timescales as the launch of a relativistic radio jet. Therefore, we may be witnessing an early stage of black hole and jet interactions in a quasar during the first billion years of the Universe.

A SPectroscopic survey of bIased halos in the Reionization Era is a quasar legacy survey primarily using JWST to target a sample of 25 z > 6 quasars with NIRCam slitless spectroscopy and imaging. The first study in this series found evidence of a strong overdensity of galaxies around J0305−3150, a luminous quasar at z = 6.61, within a single NIRCam pointing obtained in JWST Cycle 1. Here we present the first results of a JWST Cycle 2 mosaic that covers 35 arcmin ^2 with NIRCam imaging/wide-field slitless spectroscopy of the same field to investigate the spatial extent of the putative protocluster. The F356W grism data target [O iii ]+H β at 5.3 < z < 7 and reveal a population of 124 line emitters down to a flux limit of 1.2 × 10 ^−18 erg s ^−1 cm ^−2 . Fifty-three of these galaxies lie at 6.5 < z < 6.8 spanning 10 cMpc on the sky, corresponding to an overdensity within a 2500 cMpc ^3 volume of 12.5 ± 2.6, anchored by the quasar. Comparing to the [O iii ] luminosity function from the Emission line galaxies and Intergalactic Gas in the Epoch of Reionization project, we find a dearth of faint [O iii ] emitters at log( L /erg s ^−1 ) < 42.3, which we suggest is consistent with either bursty star formation causing galaxies to scatter around the grism detection limit or modest suppression from quasar feedback. While we find a strong filamentary overdensity of [O iii ] emitters consistent with a protocluster, we suggest that we could be insensitive to a population of older, more massive Lyman break galaxies with weak nebular emission on scales >​​​​​​10 cMpc.

The population of bright galaxies at $z\gtrsim10$ discovered by JWST, including the so-called "blue monsters", has been difficult to reconcile with standard galaxy evolution models. To shed light on this extraordinary population, we study the $z\sim8$ galaxies discovered by the BoRG-$JWST$ survey. These slightly-lower redshift analogs are comparable in UV luminosity to the blue monsters, and their lower redshift makes it much easier to access key rest frame optical diagnostics with NIRspec. We find that BoRG-$JWST$ galaxies are consistent with being dust-poor based on their blue UV slopes and Balmer decrement ratios. We find no strong evidence for dominant active galactic nuclei contribution to the UV brightness, based on line-ratio diagnostics, though some contribution cannot be excluded. We further infer the stellar mass, star formation and UV-brightness history of the BoRG-$JWST$ galaxies by fitting their rest-frame UV-optical spectra. We see evidence for stochastic episodes of star formation for all the BoRG-$JWST$ galaxies, providing a temporal boosting of UV luminosity in short timescales. The UV-bright blue monsters at $z\gtrsim10$ can be explained by the presence of stars with ages below 100 Myr.

We present the BoRG-JWST survey, a combination of two JWST Cycle 1 programs aimed at obtaining NIRSpec spectroscopy of representative, UV-bright 7 < z < 10 galaxy candidates across 22 independent sight lines selected from Hubble/WFC3 pure-parallel observations. We confirm the high- z nature of 12 out of 21 observed primary targets through low-resolution prism observations, with the rest revealing themselves unsurprisingly to be z ∼ 1–3 interlopers, brown dwarfs, or yielding inconclusive results. From the Multi Shutter Array (MSA) observations, we confirm an additional nine filler sources at z > 5, highlighting the large abundance of high-redshift galaxies even in individual WFC3 pointings. The primary sample spans the absolute magnitude range −20.4 mag < M _UV < −22.4 mag and harbors UV continuum slopes of β ≃ −2.5 to −2.0, representing some of the most luminous z > 7 sources currently known and comparable to the brightest NIRCam sources at z > 10. Prominent [O iii ]+H β lines are found across the full sample, while a stack of sources reveals a plethora of other rest-optical lines and additional rest-UV C III ] 1909 Å emission. Despite their luminosities, none of the low-resolution spectra display evidence for type 1 active galactic nucleus activity based on a search for broad-line emission. Lastly, we present a spectroscopic data release of 188 confirmed 0.5 ≲ z ≲ 5.0 sources from filler MSA observations, highlighting the legacy value of the survey and a representative benchmark for comparisons to deep field observations.

We present James Webb Space Telescope (JWST)/NIRSpec PRISM spectroscopic characterization of GHZ9 at z = 10.145 ± 0.010, currently the most distant source detected by the Chandra X-ray Observatory. The spectrum reveals several UV high-ionization lines, including C II , Si IV , N IV ], C IV , He II , O III ], N III ], and C III ]. The prominent rest-frame equivalent widths (EW(C IV ) ≃ 65 Å, EW(O III ]) ≃ 28 Å, and EW(C III ]) ≃ 48 Å) show the presence of a hard active galactic nucleus (AGN) radiation field, while line ratio diagnostics are consistent with either AGN or star formation as the dominant ionizing source. GHZ9 is nitrogen-enriched (6–9.5 (N/O) _⊙ ), carbon-poor (0.2–0.65 (C/O) _⊙ ), metal-poor ( Z = 0.01–0.1 Z _⊙ ), and compact (<106 pc), similarly to GN-z11, GHZ2, and recently discovered N-enhanced high redshift objects. We exploited the newly available JWST/NIRSpec and NIRCam data set to perform an independent analysis of the Chandra data confirming that GHZ9 is the most likely JWST source associated with X-ray emission at 0.5–7 keV. Assuming a spectral index Γ = 2.3 (1.8), we estimate a black hole (BH) mass of 1.60 ± 0.31 (0.48 ± 0.09) × 10 ^8 M _⊙ , which is consistent either with Eddington-accretion onto heavy (≥10 ^6 M _⊙ ) BH seeds formed at z = 18 or super-Eddington accretion onto a light seed of ∼10 ^2 –10 ^4 M _⊙ at z = 25. The corresponding BH-to-stellar mass ratio M _BH / M _star = 0.33 ± 0.22 (0.10 ± 0.07), with a stringent limit >0.02, implies an accelerated growth of the BH mass with respect to the stellar mass. GHZ9 is the ideal target to constrain the early phases of AGN–galaxy coevolution with future multifrequency observations.

We present in this paper (Paper II of the series) a 35 arcmin ^2 JWST/NIRCam imaging and wide-field slitless spectroscopy mosaic centered on J0305–3150, a luminous quasar at z = 6.61. The F356W grism data reveal 124 [O iii ]+H β emitters at 5.3 < z < 7, 53 of which constitute a protocluster spanning (10 cMpc) ^2 across 6.5 < z < 6.8. We find no evidence of any broad-line active galactic nucleus (AGN) in individual galaxies or stacking, reporting a median H β FWHM of 585 ± 152 km s ^−1 ; however, the mass–excitation diagram and “little red dot” color and compactness criteria suggest that there are a few AGN candidates on the outskirts of the protocluster. We fit the spectral energy distributions (SEDs) of the [O iii ] emitters with Prospector and Bagpipes and find that none of the SED-derived properties (stellar mass, age, or star formation rate) correlate with proximity to the quasar. While there is no correlation between galaxy age and local galaxy density, we find modest correlations of local galaxy density with increasing stellar mass, decreasing 10–100 Myr star formation rate ratios, and decreasing nebular line equivalent widths. We further find that the protocluster galaxies are consistent with being more massive, being older, and hosting higher star formation rates than the field sample at the 3 σ level, distributed in a filamentary structure that supports inside-out formation of the protocluster. There is modest evidence that galaxy evolution proceeds differently as a function of the density of local environment within protoclusters during the epoch of reionization, and the central quasar has little effect on the galaxy properties of the surrounding structure.

We present high-angular resolution (0.068", ~400pc) ALMA imaging of the [CII] line and dust continuum emission of PSO J352.4034-15.3373, a radio-loud quasar at z=5.83. The observations reveal a remarkably close match between the orientation of the [CII] and thermal dust emission mapped by ALMA, and radio synchrotron emission of a radio jet previously mapped by the VLBA. This narrow alignment extends over ~4kpc, reminiscent of the well-studied 'alignment effect' in lower-redshift radio galaxies. The [CII] kinematics show a linear increase in velocity with galactocentric radii up to ~200 km/s at r=2kpc, consistent with bulk motions within the galaxy potential, and not relativistic jet motions. The kinematics and respective morphologies are consistent with a picture in which the relativistic jet injects energy into the interstellar medium (potentially leading to subsequent star formation), giving rise to the observed alignment and significant (> 100 km/s) [CII] velocity dispersion within the host galaxy on kiloparsec scales. Indeed, the astonishingly close alignment and narrow linearity of the radio jet with the [CII] and dust emission are hard to conceive without some fundamental relationship between the two.

With enough X-ray flux to be detected in a 160 s scan by SRG/eROSITA, the z = 6.19 quasar CFHQS J142952+544717 is, by far, the most luminous X-ray source known at z > 6. We present deep (245 ks) NuSTAR observations of this source; with ∼180 net counts in the combined observations, CFHQS J142952+544717 is the most distant object ever observed by the observatory. Fortuitously, this source was independently observed by Chandra ∼110 days earlier, enabling the identification of two nearby (30″ and 45″ away), fainter X-ray sources. We jointly fit both Chandra and NuSTAR observations—self-consistently including interloper sources—and find that, to greater than 90% confidence, the observed 3–7 keV flux varied by a factor of ∼2.6 during that period, corresponding to approximately two weeks in the quasar rest frame. This brightening is one of the most extreme instances of statistically significant X-ray variability seen in the Epoch of Reionization. We discuss possible scenarios that could produce such rapid change, including X-ray emission from jets too faint at radio frequencies to be observed.

We present high-angular-resolution (0 . ″ 068, ∼400 pc) Atacama Large Millimeter/submillimeter Array (ALMA) imaging of the [C ii ] line and dust continuum emission of PSO J352.4034–15.3373, a radio-loud quasar at z = 5.83. The observations reveal a remarkably close match between the orientation of the [C ii ] and thermal dust emission mapped by ALMA and radio synchrotron emission of a radio jet previously mapped by the Very Long Baseline Array. This narrow alignment extends over ∼4 kpc, reminiscent of the well-studied “alignment effect” in lower-redshift radio galaxies. The [C ii ] kinematics show a linear increase in velocity with galactocentric radii up to ∼200 km s −1 at r = 2 kpc, consistent with bulk motions within the galaxy potential, and not relativistic jet motions. The kinematics and respective morphologies are consistent with a picture in which the relativistic jet injects energy into the interstellar medium (potentially leading to subsequent star formation), giving rise to the observed alignment and significant (≳100 km s −1 ) [C ii ] velocity dispersion within the host galaxy on kiloparsec scales. Indeed, the astonishingly close alignment and narrow linearity of the radio jet with the [C ii ] and dust emission are hard to conceive without some fundamental relationship between the two.

Relativistic jets are thought to play a crucial role in the formation and evolution of massive galaxies and supermassive black holes. Blazars, which are quasars with jets aligned along our line of sight, provide insights into the jetted population and have been observed up to redshifts of z = 6.1. Here, we report the discovery and multi-wavelength characterization of the blazar VLASS J041009.05-013919.88 at z = 7 (age of the Universe similar to 750 Myr), which is powered by a similar to 7 x 10(8) M-circle dot black hole. The presence of this high-redshift blazar implies a large population of similar but unaligned jetted sources in the early Universe. Our findings suggest two possible scenarios. In one, the jet in J0410-0139 is intrinsically low power but appears highly luminous due to relativistic beaming, suggesting that most ultraviolet-bright quasars at this redshift host jets. Alternatively, if J0410-0139 represents an intrinsically powerful radio source, there should be hundreds to thousands of radio-quiet quasars at z approximate to 7 with properties like those of J0410-0139, a prediction in tension with observed quasar densities based on their ultraviolet luminosity function. These results support the hypothesis that the rapid growth of black holes in the early Universe may be driven by jet-enhanced or obscured super-Eddington accretion, potentially playing a key role in forming massive black holes during the epoch of reionization.

We study the megaparsec-scale environments of the three highest-redshift luminous quasars at z ≥ 7.5 (J031343.84-180636.40, J134208.11+092838.61, and J100758.27+211529.21) to understand their connection to large-scale structure. Cosmological simulations show that these early supermassive black holes are expected to form in the most massive dark matter halos. Therefore, it is expected that they are anchors of galaxy overdensities if luminous matter traces the underlying dark matter structure of the Universe. Using JWST NIRCam (F090W/F115W/F250M/F360M/F430M) imaging, we observe the large-scale structure out to ∼13 comoving Mpc (cMpc) around these quasars. We select F090W-dropout Lyman-break galaxies (LBGs) and F430M-excess [O iii ] emitters in the three fields. We find 18, 21, and 6 LBG candidates in the fields of J0313, J1342, and J1007, respectively, resulting in a wide range of overdensities (1 + δ ∼ 19, 24, and 7). The photometric redshifts indicate serendipitous foreground and background overdensities in the J0313 field. The joint angular autocorrelation of the combined LBG sample shows significant clustering on <1.8 cMpc scales, demonstrating that the selected galaxies are likely associated with the large-scale structure surrounding the quasars. This first systematic study of z ∼ 7.5 quasars shows a diverse set of quasar environments at the onset of their formation, providing empirical data to help constrain theoretical predictions of early structure formation.

We present a spectroscopic redshift catalogue of sources within the Abell 2744 cluster field, derived from JWST/NIRISS observations, obtained as part of the GLASS-JWST Early Release Science programme. We describe the data reduction, the contamination modelling, and the source detection, as well as the data quality assessment, the redshift determination, and the validation. The catalogue consists of 354 secure and 134 tentative redshifts, of which 245 are new spectroscopic redshifts, spanning the range 0.1 <= z <= 8.2. These include 17 galaxies at the cluster redshift, one galaxy at z approximate to 8, and a triply imaged galaxy at z = 2.653 +/- 0.002. Comparing against galaxies with existing spectroscopic redshifts (z(spec)), we find a small offset of Delta z=(z(spec)-z(NIRISS))/(1+z(spec)) =(1.3 +/- 1.6)x10(-3). We also present a forced extraction tool (PYGRIFE) and a visualisation tool (PYGCG) to the community, to aid with the reduction and classification of grism data. This catalogue will enable future studies of the spatially resolved properties of galaxies throughout cosmic noon, including dust attenuation and star formation. As a first application of the catalogue, we discuss the spectroscopic confirmation of multiple image systems and the identification of multiple overdensities at 1

We present millimeter observations of the host galaxy of the most distant blazar known, VLASS J041009.05-013919.88 (hereafter J0410-0139) at z = 7, using Atacama Large Millimeter/submillimeter Array (ALMA) and NOrthern Extended Millimeter Array (NOEMA) observations. The ALMA data reveal a (2.02 +/- 0.36) x 10(42) erg s(-1) [C II] 158 mu m emission line at z = 6.9964 with a [C II]-inferred star formation rate (SFR) of 58 +/- 9 M-circle dot yr(-1). We estimate a dynamical mass of M-dyn,[C II(]) = (4.6 +/- 2.0) x 10(9)M(circle dot), implying a black hole mass to host a dynamical mass ratio of 0.15(-0.05)(+0.08). The 238 GHz continuum (rest-frame IR) decreased by similar to 33% from the NOEMA to the ALMA observations taken similar to 10 months apart. The Very Large Array 3-10 GHz radio flux densities showed a similar to 37% decrease in a similar time frame, suggesting a causal connection. At face value, J0410-0139 would have the lowest [CII]-to-IR luminosity ratio of a z > 5.7 quasar reported to date (similar to 10(-4)). However, if only <20% of the measured IR luminosity was due to thermal emission from dust, the [C II]-to-IR luminosity ratio would be typical of (U)LIRGs, and the SFRs derived from [C II] and IR luminosities would be consistent. These results provide further evidence that synchrotron emission significantly contributes to the observed rest-frame IR emission of J0410-0139, similar to what has been reported in some radio-loud active galactic nuclei at z < 1.