Search Publications
The evolution of the galaxy UV luminosity function at redshifts z ≃ 8 - 15 from deep JWST and ground-based near-infrared imaging
Moneti, A.; Bowler, R. A. A.; Cullen, F. +11 more
We reduce and analyse the available JWST ERO and ERS NIRCam imaging (SMACS0723, GLASS, CEERS) in combination with the latest deep ground-based near-infrared imaging in the COSMOS field (provided by UltraVISTA DR5) to produce a new measurement of the evolving galaxy UV luminosity function (LF) over the redshift range z = 8 - 15. This yields a new e…
A Sun-like star orbiting a black hole
Conroy, Charlie; Rix, Hans-Walter; Howard, Andrew W. +18 more
We report discovery of a bright, nearby ($G = 13.8;\, \, d = 480\, \rm pc$) Sun-like star orbiting a dark object. We identified the system as a black hole candidate via its astrometric orbital solution from the Gaia mission. Radial velocities validated and refined the Gaia solution, and spectroscopy ruled out significant light contributions from a…
A red giant orbiting a black hole
Conroy, Charlie; Bieryla, Allyson; Latham, David W. +18 more
We report spectroscopic and photometric follow-up of a dormant black hole (BH) candidate from Gaia DR3. The system, which we call Gaia BH2, contains a ~1 M⊙ red giant and a dark companion with mass $M_2 = 8.9\pm 0.3\, {\rm M}_{\odot }$ that is very likely a BH. The orbital period, Porb = 1277 d, is much longer than that of an…
The chemical characterization of halo substructure in the Milky Way based on APOGEE
Bizyaev, Dmitry; Cunha, Katia; Smith, Verne V. +21 more
Galactic haloes in a Λ-CDM universe are predicted to host today a swarm of debris resulting from cannibalized dwarf galaxies. The chemodynamical information recorded in their stellar populations helps elucidate their nature, constraining the assembly history of the Galaxy. Using data from APOGEE and Gaia, we examine the chemical properties of vari…
Unveiling the nature of infrared bright, optically dark galaxies with early JWST data
Brammer, G.; Oesch, P. A.; van Dokkum, P. +18 more
Over the last few years, both Atacama Large Millimeter/submillimeter Array (ALMA) and Spitzer observations have revealed a population of likely massive galaxies at z > 3 that was too faint to be detected inHubble Space Telescope(HST) rest-frame ultraviolet imaging. However, due to the very limited photometry for individual galaxies, the true na…
A first look at the SMACS0723 JWST ERO: spectroscopic redshifts, stellar masses, and star-formation histories
Cullen, F.; McLure, R. J.; Dunlop, J. S. +9 more
We present a first-look analysis of the JWST ERO data in the SMACS J0723.3-7327 cluster field. We begin by reporting 10 new spectroscopic redshifts from λobs = 1.8-5.2 µm NIRSpec medium-resolution (R = λ/Δλ = 1000) data. These are determined via multiple high-SNR emission line detections with five objects at 1 < z < 3 displa…
Parameters of 220 million stars from Gaia BP/RP spectra
Rix, Hans-Walter; Zhang, Xiangyu; Green, Gregory M.
We develop, validate and apply a forward model to estimate stellar atmospheric parameters (Teff, log g, and [Fe/H]), revised distances and extinctions for 220 million stars with XP spectra from Gaia DR3. Instead of using ab initio stellar models, we develop a data-driven model of Gaia XP spectra as a function of the stellar parameters, …
The ultraviolet continuum slopes (β) of galaxies at z ≃ 8-16 from JWST and ground-based near-infrared imaging
Bowler, R. A. A.; McLure, R. J.; Dunlop, J. S. +7 more
We study the rest-frame ultraviolet (UV) continuum slopes (β) of galaxies at redshifts 8 < z < 16 (⟨z⟩ = 10), using a combination of JWST ERO and ERS NIRCam imaging and ground-based near-infrared imaging of the COSMOS field. The combination of JWST and ground-based imaging provides a wide baseline in both redshift and absolute UV magnitude (…
Star formation at the smallest scales: a JWST study of the clump populations in SMACS0723
Mahler, Guillaume; Richard, Johan; Adamo, Angela +3 more
We present the clump populations detected in 18 lensed galaxies at redshifts 1--8.5 within the lensing cluster field SMACS0723. The recent JWST Early Release Observations of this poorly known region of the sky have revealed numerous point-like sources within and surrounding their host galaxies, undetected in the shallower Hubble Space Telescope im…
galstreams: A library of Milky Way stellar stream footprints and tracks
Mateu, Cecilia
Nearly a hundred stellar streams have been found to date around the Milky Way and the number keeps growing at an ever faster pace. Here we present the galstreams library, a compendium of angular position, distance, proper motion, and radial velocity track data for nearly a hundred (95) Galactic stellar streams. The information published in the lit…