TDCOSMO 2025: Cosmological constraints from strong lensing time delays
Astronomy & Astrophysics EDP Sciences 704 (2025) a63
Abstract:
We present cosmological constraints from eight strongly lensed quasars (hereafter, the TDCOSMO-2025 sample). Building on previous work, our analysis incorporated new deflector stellar velocity dispersions measured from spectra obtained with the James Webb Space Telescope (JWST), the Keck Telescopes, and the Very Large Telescope (VLT), utilizing improved methods. We used integrated JWST stellar kinematics for five lenses, VLT-MUSE for 2, and resolved kinematics from Keck and JWST for RX J1131−1231. We also considered two samples of non-time-delay lenses: 11 from the Sloan Lens ACS (SLACS) sample with Keck-KCWI resolved kinematics; and four from the Strong Lenses in the Legacy Survey (SL2S) sample. We improved our analysis of line-of-sight effects, the surface brightness profile of the lens galaxies, and orbital anisotropy, and corrected for projection effects in the dynamics. Our uncertainties are maximally conservative by accounting for the mass-sheet degeneracy in the deflectors’ mass density profiles. The analysis was blinded to prevent experimenter bias. Our primary result is based on the TDCOSMO-2025 sample, in combination with Ω m constraints from the Pantheon+ Type Ia supernovae (SN) dataset. In the flat Λ cold dark matter (CDM), we find H 0 = 71.6 +3.9 −3.3 km s −1 Mpc −1 . The SLACS and SL2S samples are in excellent agreement with the TDCOSMO-2025 sample, improving the precision on H 0 in flat ΛCDM to 4.6%. Using the Dark Energy Survey SN Year-5 dataset (DES-SN5YR) or DESI-DR2 baryonic acoustic oscillations (BAO) likelihoods instead of Pantheon+ yields very similar results. We also present constraints in the open ΛCDM, w CDM, w 0 w a CDM, and w ϕ CDM cosmologies. The TDCOSMO H 0 inference is robust and consistent across all presented cosmological models, and our cosmological constraints in them agree with those from the BAO and SN.JADES and BlackTHUNDER: rest-frame Balmer-line absorption and the local environment in a Little Red Dot at z = 5
Monthly Notices of the Royal Astronomical Society 91̽»¨ University Press 545:3 (2025) staf2117
Abstract:
We present a ‘Little Red Dot’ (LRD) broad-line active galactic nucleus (AGN) at , observed with NIRSpec/MSA (micro-shutter assembly) and NIRSpec/IFU (integral-field unit) by the JADES (JWST Advanced Deep Extragalactic Survey) and BlackTHUNDER (Black holes in THe early Universe aNd their DensE surRoundings) surveys. Combining spatially resolved and high-resolution spectroscopy, we characterize its central engine, host, and environment. H has multiple components, including two broad Gaussians, yielding a black-hole mass , while [O iii]5007 gives a galaxy dynamical mass , suggesting an overmassive black hole relative to the host galaxy. The target is immersed in a 7-kpc wide pool of ionized gas and has three neighbours: a satellite galaxy, a possible satellite/gas cloud, and a tentatively detected spatially detached outflow. H shows strong, rest-frame absorption, deeper than the continuum, ruling out a stellar origin. The velocity and velocity dispersion are and . There is tentative evidence (2.6σ) of temporal variability in the equivalent width of the H absorber over two rest-frame months, suggesting a highly dynamic nucleus. Notably, while the H absorber is clearly visible and even dominant in the high-resolution G395H observations, it is not detected in the medium-resolution G395M data of the same epoch. This implies that the current incidence rate of absorbers in LRDs – and especially of rest-frame absorbers – may be severely underestimated, because most LRDs rely on lower resolution spectroscopy. The high incidence rate of rest-frame absorbers in LRDs may indicate a configuration that is either intrinsically stationary, such as a rotating disc, or that exhibits time-averaged stability, such as an oscillatory ‘breathing mode’ accretion with cyclic expansion and contraction of the gas around the supermassive black hole.GATOS. VIII. On the Physical Origin of the Extended Mid-infrared Emission in Active Galactic Nuclei
The Astrophysical Journal American Astronomical Society 994:2 (2025) 206
Abstract:
The polar mid-infrared (MIR) emission detected within tens to hundreds of parsecs in some active galactic nuclei (AGN) has been associated with dusty winds driven away by radiation pressure. The physical characterization of this extended polar emission remains uncertain. Here, we combine 10–21 μm JWST/Mid-InfRared Instrument (MIRI) imaging observations with 7–25 μm JWST/MIRI MRS integral field spectroscopic observations of six nearby, D¯=35.4±4.6 Mpc, AGN from the GATOS Survey to quantify the nature of the extended MIR emission at ∼75 pc resolution at 21 μm. These AGN have similar bolometric luminosities, log10(L¯bol[ergs−1])=44.0±0.3 , span a wide range of optical outflow rates, Ṁ= 0.003–0.21 M⊙ yr−1, column densities, log10(NHX−ray[cm−2])= 22.2–24.3, and Eddington ratios, λEdd = 0.005–0.06. We cross-correlate the line-only and continuum-only images and find a poor correlation, which indicates that the extended MIR continuum emission is spatially uncorrelated with the warm outflows associated with narrow emission lines within 10–15 μm. Line emission is resolved along the jet axis, while dust emission is perpendicular to it. The 75–450 pc continuum emission has a fairly constant dust temperature, Td=132−7+7 K, and mass, Md=728−27+29 M⊙. Using the conditions of energy balance between radiation-pressure and gravity (λEdd versus NH), we find that our AGN sample is in the gravitationally bounded regime consistent with no detection of dusty winds. At 10 μm, the level of extended line emission contribution is correlated with the outflow kinetic energy and mass outflow rates. We find no correlation with the AGN properties. These results indicate that the radio jet may be triggering the gas outflow and line emission, while the extended dust emission is distributed in molecular clouds and/or shocked regions.JADES: Carbon-enhanced, Nitrogen-normal compact galaxy at z=11.2
Monthly Notices of the Royal Astronomical Society (2025) staf2107
Abstract:
Over the past few years JWST has been a major workhorse in detecting and constraining the metal enrichment of the first galaxies in the early Universe and finding the source of the ionisation of their interstellar medium. In this work, we present new deep JWST/NIRSpec spectroscopy of GS-z11-1, a galaxy at z = 11.28, in which we report the detection of multiple rest-frame UV and optical emission lines: CIII]λλ1907,09, CIV]λλ1548,51, [OII]λλ3726,29, [NeIII]λ3869, Hγ and tentative evidence for HeIIλ1640. The ionisation properties of GS-z11-1 are consistent with star formation, with potential contribution from an active galactic nucleus (AGN). We estimate a galaxy stellar mass of log(M⋆/M⊙) = 7.8±0.2 and log(SFR/(M⊙ yr−1))= 0.32±0.11 for the fiducial SF-only models. We measured C/O from the SED modelling of C/O = 1.20±0.15 × solar. This is one of the highest C/O abundances at z>10, and it is consistent with either PopII and PopIII enrichment paths. Despite this source being extremely compact, with a half-light radius of 73±10 pc, we see no increased equivalent width of NIV] and NIII] emission lines as seen in some other compact sources at similar redshifts, a potential signature of second-generation stars in GCs. Overall, this galaxy exhibits low metallicity and high ionisation parameter consistent with intense star-formation or AGN activity in the early Universe, possibly observed before the enrichment by the second generation of stars in proto-globular clusters in the core of the galaxy.Kinematics show consistency between stellar mass and supermassive black hole parent population jet speeds
Monthly Notices of the Royal Astronomical Society 91̽»¨ University Press 545:4 (2025) staf2102