Kavli Affiliate: Mark Vogelsberger | Summary:Recombinations during the Epoch of Reionization are intrinsically inhomogeneous, with different regions of the intergalactic medium contributing unevenly depending on their density, temperature, ionization state, and spatial patchiness. We combine the high- and medium-resolution 95.5 cMpc Thesan-1 andh Thesan-2 runs with the significantly larger 500 cMpc Lumina simulation to measure […]

Kavli Affiliate: Dheeraj Pasham | Summary:We present JWST/NIRCam observations of the extremely long-duration gamma-ray burst (GRB) 250702B taken at ~ 95 days post-GRB (observer frame). The observations of the host galaxy reveal a single galaxy with a prominent dust lane observed nearly edge-on. Prospector modeling of the host galaxy photometry finds a high stellar mass […]

Kavli Affiliate: Erin Kara | Summary:The intracluster medium (ICM) is rich in chemical elements, produced by core-collapse (SNcc) and Type Ia supernovae (SNIa) over the last $sim$12 Gyr. Whereas cluster outskirts are uniformly enriched with Fe at $sim$0.3 solar – strongly suggesting that the gas had been pre-enriched during or before the assembly of galaxies […]

Kavli Affiliate: Erin Kara | Summary:The intracluster medium (ICM) is rich in chemical elements, produced by core-collapse (SNcc) and Type Ia supernovae (SNIa) over the last $sim$12 Gyr. Whereas cluster outskirts are uniformly enriched with Fe at $sim$0.3 solar – strongly suggesting that the gas had been pre-enriched during or before the assembly of galaxies […]

Kavli Affiliate: Michael Fausnaugh | Summary:The Luminous Fast Blue Optical Transient (LFBOT) AT2022tsd exhibited minutes-timescale optical flares in the tens of days following the initial transient event, likely due to a central engine — either an accreting black hole or a magnetar. In this paper, we use data from the Transiting Exoplanet Survey Satellite (TESS) […]

Kavli Affiliate: Lina Necib | Summary:Understanding how galaxies like the Milky Way assembled over cosmic time remains a central question in astrophysics. Understanding the processes that shaped their formation and evolution is greatly enhanced by the joint use of observational data and high-resolution cosmological simulations. Old stars in the inner regions of galaxies serve as […]

Kavli Affiliate: Mark Vogelsberger | Summary:Understanding the sources and evolution of cosmic reionization remains a central challenge in astrophysics, with the escape of ionizing Lyman-continuum (LyC) photons from early galaxies representing a major uncertainty. In this work, we use more than 35,000 galaxy realisations from the THESAN-ZOOM cosmological radiation-hydrodynamic simulations to identify indirect diagnostics of […]

Kavli Affiliate: Mark Vogelsberger | Summary:The JWST discoveries of supermassive black holes (BHs) at $z gtrsim 5$ may provide key insights into their seeding origins. Using new $[18-72~rm Mpc]^3$ BRAHMA cosmological simulations, we investigate how variations in heavy-seed prescriptions, coupled with a subgrid dynamical friction model, shape BH populations at $z sim 5$ and $z […]

Kavli Affiliate: Anna Frebel | Summary:Carbon-enhanced metal-poor (CEMP; with $rm[Fe/H] le -2.0$ and $rm[C/Fe] ge 0.7$) stars preserve information about early chemical enrichment, low-mass star formation, and the hierarchical assembly of galaxies. In this study, we have compiled an extensive literature sample of 1032 stellar carbon abundances spanning the metal-poor Milky Way halo (437 stars), […]

Kavli Affiliate: Salvatore Vitale | Summary:The distribution of the effective inspiral spin ($χ_mathrmeff$) of the binary black holes detected by LIGO-Virgo-KAGRA can shed light on their formation pathways. We analyze the GWTC-5.0 dataset with two models-one flexible, one fully parametric-that jointly describe $χ_mathrmeff$ and primary mass. We clarify that the previously-reported skewness in the $χ_mathrmeff$ […]