Search Publications
Strong constraints on the gravitational law from Gaia DR3 wide binaries
Mieske, Steffen; Famaey, Benoit; Ibata, Rodrigo +4 more
We test Milgromian dynamics (MOND) using wide binary stars (WBs) with separations of 2-30 kAU. Locally, the WB orbital velocity in MOND should exceed the Newtonian prediction by $\approx 20~{{\ \rm per\ cent}}$ at asymptotically large separations given the Galactic external field effect (EFE). We investigate this with a detailed statistical analys…
Fundamental scaling relationships revealed in the optical light curves of tidal disruption events
Ingram, Adam; van Velzen, Sjoert; Hammerstein, Erica +4 more
We present fundamental scaling relationships between properties of the optical/UV light curves of tidal disruption events (TDEs) and the mass of the black hole that disrupted the star. We have uncovered these relations from the late-time emission of TDEs. Using a sample of 63 optically selected TDEs, the latest catalogue to date, we observed flatt…
Chasing the impact of the Gaia-Sausage-Enceladus merger on the formation of the Milky Way thick disc
Ting, Yuan-Sen; Grand, Robert J. J.; Fragkoudi, Francesca +8 more
We employ our Bayesian Machine Learning framework BINGO (Bayesian INference for Galactic archaeOlogy) to obtain high-quality stellar age estimates for 68 360 red giant and red clump stars present in the 17th data release of the Sloan Digital Sky Survey, the APOGEE-2 high-resolution spectroscopic survey. By examining the denoised age-met…
Insight from JWST/Near Infrared Camera into galaxy overdensities around bright Lyman-alpha emitters during reionization: implications for ionized bubbles at z 9
Charlot, Stéphane; Chen, Zuyi; Stark, Daniel P. +4 more
Several studies have detected Lyman-alpha (Ly Α) from bright ($M_{\small UV}\lesssim -21.5$) galaxies during the early stages of reionization despite the significantly neutral intergalactic medium. To explain these detections, it has been suggested that z > 7 Ly Α emitters (LAEs) inhabit physical Mpc (pMpc)-scale ionized regions powered by over…
Ionizing properties of galaxies in JADES for a stellar mass complete sample: resolving the cosmic ionizing photon budget crisis at the Epoch of Reionization
Maiolino, R.; Johnson, B. D.; Willott, C. +26 more
We use NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) to study the ionizing properties of a sample of 14 652 galaxies at
A JWST investigation into the bar fraction at redshifts 1 ≤ z ≤ 3
Conselice, Christopher J.; Fragkoudi, Francesca; Ferreira, Leonardo +7 more
The presence of a stellar bar in a disc galaxy indicates that the galaxy hosts in its main part a dynamically settled disc and that bar-driven processes are taking place in shaping its evolution. Studying the cosmic evolution of the bar fraction in disc galaxies is therefore essential to understand galaxy evolution in general. Previous studies hav…
Bursty star formation and galaxy-galaxy interactions in low-mass galaxies 1 Gyr after the Big Bang
Willott, Chris J.; Harshan, Anishya; Bradač, Maruša +14 more
We use CANUCS JWST/NIRCam imaging of galaxies behind the gravitationally-lensing cluster MACS J0417.5-1154 to investigate star formation burstiness in low-mass (M⋆ ~ 108 M⊙) galaxies at z ~ 4.7-6.5. Our sample of 123 galaxies is selected using the Lyman break selection and photometric emission-line excess methods. …
GA-NIFS: an extremely nitrogen-loud and chemically stratified galaxy at z 5.55
Charlot, Stéphane; Übler, Hannah; D'Eugenio, Francesco +11 more
We report the chemical abundance pattern of GS_3073, a galaxy hosting an overmassive active black hole at
JWST spectroscopy of z 5-8 UV-selected galaxies: new constraints on the evolution of the Ly α escape fraction in the reionization era
Charlot, Stéphane; Chen, Zuyi; Tang, Mengtao +5 more
We describe JWST/NIRSpec prism measurements of Ly α emission in z ≳ 5 galaxies. We identify Ly α detections in 10 out of 69 galaxies with robust rest-optical emission-line redshift measurements at 5 ≤ z < 7 in the Cosmic Evolution Early Release Science (CEERS) and DDT-2750 observations of the Extended Groth Strip field. Galaxies at z ≃ 6 with f…
Strong gravitational lensing's 'external shear' is not shear
Koekemoer, Anton M.; Mahler, Guillaume; Frye, Brenda L. +20 more
The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus 'external shear', which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight. A small amount of external shear could come from these sources, but we show that the vast majority does not. Except in…