Dark Matter in Draco and Boötes I: Hints of a Core in an Ultra-Faint Dwarf from Simulation-Based Inference

Kavli Affiliate: Lina Necib | Summary:The density profiles of dwarf spheroidal galaxies are among the most sensitive probes of dark matter physics, yet extracting them from noisy stellar kinematics remains a fundamental obstacle. We present GraphNPE, a simulation-based inference method for dynamical mass modeling that incorporates measurement uncertainties and spectroscopic selection functions in the forward […]


Continue.. Dark Matter in Draco and Boötes I: Hints of a Core in an Ultra-Faint Dwarf from Simulation-Based Inference

Observation of A Solar Like Magnetic Reconnection Event in an AGN Corona with XRISM

Kavli Affiliate: Erin Kara | Summary:The X-ray source in AGN is commonly referred to as the corona by analogy to stellar coronae. The similarities between the two suggest that the heating mechanism of AGN coronae is magnetic reconnection — as in cool stars — but this has not yet been directly observed. This work presents […]


Continue.. Observation of A Solar Like Magnetic Reconnection Event in an AGN Corona with XRISM

Observation of A Solar Like Magnetic Reconnection Event in an AGN Corona with XRISM

Kavli Affiliate: Erin Kara | Summary:The X-ray source in AGN is commonly referred to as the corona by analogy to stellar coronae. The similarities between the two suggest that the heating mechanism of AGN coronae is magnetic reconnection — as in cool stars — but this has not yet been directly observed. This work presents […]


Continue.. Observation of A Solar Like Magnetic Reconnection Event in an AGN Corona with XRISM

Kepler Image-Subtracted Light Curves and Variable Star Catalog of NGC 6819

Kavli Affiliate: Andrew Vanderburg | Summary:Variable stars in open clusters are valuable probes of stellar evolution. They provide precise measurements of stellar properties, constrain cluster ages and distances, and trace the angular momentum evolution of stellar populations. To advance these studies, we applied image subtraction and systematic reduction techniques to the NGC 6819 Kepler superstamp […]


Continue.. Kepler Image-Subtracted Light Curves and Variable Star Catalog of NGC 6819

Kepler Image-Subtracted Light Curves and Variable Star Catalog of NGC 6819

Kavli Affiliate: Andrew Vanderburg | Summary:Variable stars in open clusters are valuable probes of stellar evolution. They provide precise measurements of stellar properties, constrain cluster ages and distances, and trace the angular momentum evolution of stellar populations. To advance these studies, we applied image subtraction and systematic reduction techniques to the NGC 6819 Kepler superstamp […]


Continue.. Kepler Image-Subtracted Light Curves and Variable Star Catalog of NGC 6819

Observing a 542-day transiting giant with large TTVs: The 2025 transit of HIP 41378 f and new constraints on the outer system

Kavli Affiliate: Avi Shporer | Summary:Characterizing long-period transiting exoplanets is inherently challenging due to the rarity and long duration of transit events. Yet, these systems provide unique insights into planetary formation, migration, the detection of exomoons, and primordial atmospheres by occupying a sparsely populated region of the exoplanet parameter space. The complexity increases further for […]


Continue.. Observing a 542-day transiting giant with large TTVs: The 2025 transit of HIP 41378 f and new constraints on the outer system

Observing a 542-day transiting giant with large TTVs: The 2025 transit of HIP 41378 f and new constraints on the outer system

Kavli Affiliate: Avi Shporer | Summary:Characterizing long-period transiting exoplanets is inherently challenging due to the rarity and long duration of transit events. Yet, these systems provide unique insights into planetary formation, migration, the detection of exomoons, and primordial atmospheres by occupying a sparsely populated region of the exoplanet parameter space. The complexity increases further for […]


Continue.. Observing a 542-day transiting giant with large TTVs: The 2025 transit of HIP 41378 f and new constraints on the outer system

JWST-TST High Contrast: First Direct Spectroscopy of GJ 504 b reveals Clouds and Possible Metal Enrichment

Kavli Affiliate: Sara Seager | Summary:Characterizing the coldest directly imaged companions through direct spectroscopy has only recently become possible with the James Webb Space Telescope. We present moderate-resolution (R $sim$ 2,700) spectroscopic observations of the directly imaged planetary-mass companion (PMC), GJ 504 b, using the $JWST$/NIRSpec. As the coldest imaged PMC of the pre-JWST era […]


Continue.. JWST-TST High Contrast: First Direct Spectroscopy of GJ 504 b reveals Clouds and Possible Metal Enrichment

Reconstructing Galactic Gravitational Potentials from Stellar Kinematics with Physics-Informed Neural Networks

Kavli Affiliate: Lina Necib | Summary:The gravitational potential of a galaxy encodes its mass distribution, formation history, and dark matter halo structure. Accurate potential models are therefore critical for interpreting stellar kinematics, orbital dynamics, and the influence of satellite systems like the Large Magellanic Cloud. Analytic potential models offer interpretability and efficiency but struggle to […]


Continue.. Reconstructing Galactic Gravitational Potentials from Stellar Kinematics with Physics-Informed Neural Networks

The Lumina Project: Intergalactic Clumping and Recombination Sinks

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 […]


Continue.. The Lumina Project: Intergalactic Clumping and Recombination Sinks