Kavli Affiliate: Mark Vogelsberger | Summary:Understanding how galaxies and active galactic nuclei (AGN) jointly drive the reionization of the intergalactic medium (IGM) across cosmic time remains a major challenge in cosmology. We present Lumina, a large-volume radiation-hydrodynamic simulation that self-consistently follows the coupled evolution of the intergalactic medium, galaxies, and AGN through HI, HeI, and […]

Kavli Affiliate: Moritz Guenther | Summary:The Chandra Interactive Analysis of Observations (CIAO) software, developed by the Chandra X-ray Center, has been the data analysis package for the Chandra X-ray Observatory since its launch in 1999. Over nearly three decades, CIAO has grown from a small software suite into a widely used system for X-ray data […]

Kavli Affiliate: Anna Frebel | Summary:Ultra-faint dwarf galaxies (UFDs, $M_* < 10^5 M_odot$) offer unique insights into early chemical evolution in low-mass systems. However, interpreting their metallicity distribution functions (MDFs) has been challenging due to limited spectroscopic samples, especially beyond the red giant branch. We present metallicities from the Ca II K absorption feature, measured […]

Kavli Affiliate: Avi Shporer | Summary:We report the discovery and characterisation of the multi-planetary system around TOI-4311, a K dwarf kinematically between the Galactic thick disk and Hercules stream. TOI-4311 hosts an ultra-short-period super-Earth (P$sim$0.99 d, $1.376substack+0.077\-0.080$ R$_oplus$) and a longer period sub-Neptune (P$sim$15 d, $2.47substack+0.12\-0.11$ R$_oplus$) that was first detected in the TESS photometry. […]

Kavli Affiliate: Paul Schechter | Summary:Lensed supernovae (SNae) are among the most eagerly anticipated transients expected from the Legacy Survey of Space and Time (LSST). Quadruply lensed SNae permit more highly constrained models than "mere" doubles. The quadruply lensed SN 2025wny offers multiple lessons on how one might respond to an alert. The full benefits […]

Kavli Affiliate: Anna Frebel | Summary:As part of the ongoing work of the $R$-Process Alliance (RPA), detailed abundance measurements of 29 heavy elements in three metal-poor stars, 2MASS J14592981$-$3852558, 2MASS J19445483$-$4039459, and 2MASS J15211026$-$0607566, are presented based on an analysis of high-resolution ($Rsim 80,000$), high signal-to-noise “portrait” spectra from the Magellan Inamori Kyocera Echelle (MIKE) […]

Kavli Affiliate: Kiyoshi Masui | Summary:We present 30 newly discovered repeating fast radio burst (FRB) sources from the second catalog of bursts detected by the FRB backend on the Canadian Hydrogen Intensity Mapping Experiment (CHIME/FRB). These repeaters have extragalactic dispersion measures (DMs) spanning $99.4-1446.0 textpc cm^-3$ and burst rates between $10^-5.7$ and $10^-0.5$ hr$^-1$ scaled […]

Kavli Affiliate: Sara Seager | Summary:TRAPPIST-1 is an ultra-cool dwarf that flares frequently. These flares shape the surrounding planets’ high-energy irradiation environments, with consequences for atmospheric chemistry and escape, and they can contaminate transmission spectroscopy of those planets. A quantitative flare-frequency distribution (FFD) spanning the full energy range is therefore essential for both interpreting JWST […]

Kavli Affiliate: Salvatore Vitale | Summary:The degree of black-hole spin-orbit misalignment ("tilts") in the astrophysical population could be a powerful diagnostic to distinguish between binary formation in isolation, in dynamical environments, or in hierarchical triples. However, robust population-level spin tilt measurements are complicated by model misspecification as well as numerical and Poisson variance, ultimately owing […]

Kavli Affiliate: Lina Necib | Summary:The merger history of a galaxy leaves imprints on its present-day stellar chemodynamics, yet dynamical processes progressively erase this record. We ask: how far back in time, and from which observables, can a galaxy’s assembly history still be recovered? We provide a quantitative framework to address this question, using Mutual […]