Search Publications

A double take on early and interacting dark energy from JWST
DOI: 10.1088/1475-7516/2024/05/097 Bibcode: 2024JCAP...05..097F

Melchiorri, Alessandro; Mena, Olga; Nunes, Rafael C. +4 more

The very first light captured by the James Webb Space Telescope (JWST) revealed a population of galaxies at very high redshifts more massive than expected in the canonical ΛCDM model of structure formation. Barring, among others, a systematic origin of the issue, in this paper, we test alternative cosmological perturbation histories. We argue that…

2024 Journal of Cosmology and Astroparticle Physics
JWST 30
Beyond Gaia DR3: Tracing the [α/M] - [M/H] bimodality from the inner to the outer Milky Way disc with Gaia-RVS and convolutional neural networks
DOI: 10.1051/0004-6361/202347122 Bibcode: 2024A&A...682A...9G

Guiglion, G.; Fabbro, S.; Valentini, M. +17 more

Context. In June 2022, Gaia DR3 provided the astronomy community with about one million spectra from the Radial Velocity Spectrometer (RVS) covering the CaII triplet region. In the next Gaia data releases, we anticipate the number of RVS spectra to successively increase from several 10 million spectra to eventually more than 200 million spectra. T…

2024 Astronomy and Astrophysics
Gaia 30
A mature quasar at cosmic dawn revealed by JWST rest-frame infrared spectroscopy
DOI: 10.1038/s41550-024-02273-0 Bibcode: 2024NatAs...8.1054B

Henning, Thomas; Costantin, Luca; Langeroodi, Danial +29 more

The rapid assembly of the first supermassive black holes is an enduring mystery. Until now, it was not known whether quasar `feeding' structures (the `hot torus') could assemble as fast as the smaller-scale quasar structures. We present JWST/MRS (rest-frame infrared) spectroscopic observations of the quasar J1120+0641 at z = 7.0848 (well within th…

2024 Nature Astronomy
JWST 30
The Three-phase Evolution of the Milky Way
DOI: 10.3847/1538-4357/ad5b60 Bibcode: 2024ApJ...972..112C

Conroy, Charlie; Hernquist, Lars; Li, Jiadong +6 more

We illustrate the formation and evolution of the Milky Way over cosmic time, utilizing a sample of 10 million red giant stars with full chemodynamical information, including metallicities and α-abundances from low-resolution Gaia XP spectra. The evolution of angular momentum as a function of metallicity—a rough proxy for stellar age, particularly …

2024 The Astrophysical Journal
Gaia 30
A nebular origin for the persistent radio emission of fast radio bursts
DOI: 10.1038/s41586-024-07782-6 Bibcode: 2024Natur.632.1014B

Tripodi, Roberta; Savaglio, Sandra; Zhang, Bing +12 more

Fast radio bursts (FRBs) are millisecond-duration, bright (approximately Jy) extragalactic bursts, whose production mechanism is still unclear1. Recently, two repeating FRBs were found to have a physically associated persistent radio source of non-thermal origin2,3. These two FRBs have unusually large Faraday rotation measure…

2024 Nature
eHST 30
Hubble tension or distance ladder crisis?
DOI: 10.1103/PhysRevD.110.123518 Bibcode: 2024PhRvD.110l3518P

Perivolaropoulos, Leandros

We present an up-to-date compilation of published Hubble constant (H0) measurements that are independent of the cosmic microwave background sound horizon scale. This compilation is split in two distinct groups: A. Distance …

2024 Physical Review D
Gaia 29
Triage of the Gaia DR3 astrometric orbits. II. A census of white dwarfs
DOI: 10.1093/mnras/stae773 Bibcode: 2024MNRAS.529.3729S

Mazeh, T.; Shahaf, S.; Toonen, S. +4 more

The third data release of Gaia was the first to include orbital solutions assuming non-single stars. Here, we apply the astrometric triage technique of Shahaf et al. to identify binary star systems with companions that are not single main-sequence stars. Gaia's synthetic photometry of these binaries is used to distinguish between systems likely to…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 29
GJ 367b Is a Dark, Hot, Airless Sub-Earth
DOI: 10.3847/2041-8213/ad1a07 Bibcode: 2024ApJ...961L..44Z

Knutson, Heather A.; Hu, Renyu; Dai, Fei +6 more

We present the mid-infrared (5–12 µm) phase curve of GJ 367b observed by the Mid-Infrared Instrument on the James Webb Space Telescope (JWST). GJ 367b is a hot (T eq = 1370 K), extremely dense (10.2 ± 1.3 g cm‑3) sub-Earth orbiting an M dwarf on a 0.32 day orbit. We measure an eclipse depth of 79 ± 4 ppm, a nightside pl…

2024 The Astrophysical Journal
JWST 29
PDRs4All. II. JWST's NIR and MIR imaging view of the Orion Nebula
DOI: 10.1051/0004-6361/202346747 Bibcode: 2024A&A...685A..73H

Hartigan, Patrick; Zhang, Yong; Gordon, Karl D. +139 more

Context. The James Webb Space Telescope (JWST) has captured the most detailed and sharpest infrared (IR) images ever taken of the inner region of the Orion Nebula, the nearest massive star formation region, and a prototypical highly irradiated dense photo-dissociation region (PDR).
Aims: We investigate the fundamental interaction of far-ultra…

2024 Astronomy and Astrophysics
eHST JWST 29
Unveiling the hidden Universe with JWST: the contribution of dust-obscured galaxies to the stellar mass function at z 3 - 8
DOI: 10.1093/mnras/stae754 Bibcode: 2024MNRAS.530..966G

Xiao, M.; Brammer, G.; Toft, S. +17 more

With the advent of JWST, we can probe the rest-frame optical emission of galaxies at $z\gt 3$ with high sensitivity and spatial resolution, making it possible to accurately characterize red, optically faint galaxies and thus move towards a more complete census of the galaxy population at high redshifts. To this end, we present a sample of 148 mass…

2024 Monthly Notices of the Royal Astronomical Society
eHST JWST 29