Kavli Affiliate: Mark Vogelsberger | Summary:Early JWST/NIRCam surveys revealed a puzzling population of high-redshift massive galaxy candidates largely absent from previous rest-frame UV surveys. Spectroscopic follow-up has both confirmed and contested these candidates, whose potential overabundance may challenge traditional models of galaxy formation. In this study we evaluate the reliability of the photometric selections used […]

Kavli Affiliate: Eric Miller | Summary:We present the results of a deep 251 ks XRISM/Resolve observation of the cool core of the galaxy cluster Abell 2199. From the integrated spectrum of the central $3′ times 3’$ Resolve field of view ($104 times 104 mathrm~kpc^2$), we find that the intracluster medium (ICM) redshift is consistent with […]

Kavli Affiliate: Mark Vogelsberger | Summary:Self-interacting dark matter (SIDM) influences halo structure through collisional heat transport and may solve several small-scale puzzles in structure formation. SIDM creates thermalized cores in low-mass haloes, which may account for the observed cored dwarf galaxies. During late-time gravothermal core collapse, SIDM can produce dense low-mass DM haloes and substructures […]

Kavli Affiliate: Erin Kara | Summary:We present results from a comprehensive multi-wavelength monitoring campaign of the changing-look active galactic nucleus 1ES 1927+654 during the onset and evolution of a radio jet (May 2022-August 2025). Using observations from XMM-Newton, Swift, TNG, ZTF, VLA, and VLBA, we characterize the spectral evolution of the source. Soft X-ray emission […]

Kavli Affiliate: Michael Fausnaugh | Summary:We report the discovery of Gaia23bra b, the first gravitationally bound microlensing planet detected by the Transiting Exoplanet Survey Satellite (TESS). Initially flagged as a single-lens event by the Gaia Science Alerts system, Gaia23bra was serendipitously observed by TESS over two consecutive sectors. During those TESS sectors, the light curve […]

Kavli Affiliate: Andrew Vanderburg | Summary:We revisit the TOI-2134 planetary system with three new high-cadence TESS sectors and 98 more spectra. This new analysis confirms the two orbiting planets by simultaneously modelling a total of eight sectors of corrected TESS photometry and 280 HARPS-N and SOPHIE radial velocities: an inner mini-Neptune in a near-circular $9.229198pm0.000003$ […]

Kavli Affiliate: Andrew Vanderburg | Summary:We revisit the TOI-2134 planetary system with three new high-cadence TESS sectors and 98 more spectra. This new analysis confirms the two orbiting planets by simultaneously modelling a total of eight sectors of corrected TESS photometry and 280 HARPS-N and SOPHIE radial velocities: an inner mini-Neptune in a near-circular $9.229198pm0.000003$ […]

Kavli Affiliate: Erin Kara | Summary:Tidal Disruption Events (TDEs) serve as direct probes of the population of supermassive black holes in the center of galaxies and are nowadays regularly detected in optical wide-field time-domain sky surveys. Recent studies have demonstrated that a large fraction of TDEs can be uniquely identified in the infrared (IR) waveband, […]

Kavli Affiliate: Robert Simcoe | Summary:JWST’s Little Red Dots (LRDs) display a unique constellation of features that do not occur simultaneously in any other class of galaxies or AGN. Here we observe that many of these features find parallels in the 19th century Great Eruption (GE) of $η$ Carinae and a sub-class of supernovae (Type […]

Kavli Affiliate: Sara Seager | Summary:Gas giant planets with periods $20~<~P~<~300~rm days$ orbiting Sun-like stars are a relatively uncommon outcome of planetary formation, and key questions about the nature and formation of this sub-population remain unanswered. Theoretical models for the location of their formation (in- or ex-situ) and for their subsequent migration predict different outcomes […]