February 2026 – Page 13 – Kavli Institute Pre-Print Publications

Direct pathway to the Early Supermassive Black Holes: A Red Super-Eddington Quasar in a Massive Starburst Host at $z=7.2$

Posted by klaurent February 12, 2026February 23, 2026Peking

Kavli Affiliate: Luis Ho | Summary:We present a panchromatic optical-mm characterization of GNz7q, a recently identified X-ray weak, rapidly growing red quasar embedded within a dusty starburst galaxy at $z=7.1899$, using the full suite of JWST/NIRCam, NIRSpec, MIRI, and archival NOEMA observations. Our deep NIRSpec/G395M spectroscopy reveals unambiguous broad Balmer emission (FWHM $=2221pm20$kms$^-1$), confirming a […]

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A simple model for extracting astrophysics from black hole images

Posted by klaurent February 12, 2026February 23, 2026Chicago

Kavli Affiliate: Daniel Holz | Summary:The Event Horizon Telescope (EHT) is providing unprecedented high-resolution images of supermassive black holes. These images are fundamentally related to properties of the luminous accretion disks, since black holes themselves produce no light. We develop a simple prescription to relate observational features of black hole images to a toy model […]

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Is cosmic birefringence due to dark energy or dark matter? Simulation-based inference

Posted by klaurent February 12, 2026February 23, 2026Tokyo

Kavli Affiliate: Eiichiro Komatsu | Summary:Simulation-based inference (SBI) is a powerful inference technique for cases where the exact functional form of the likelihood is not known. A prime example is the likelihood of cross-correlation power spectra of the cosmic microwave background (CMB) fields at low multipoles, $elllesssim 10$. In this paper, we investigate a parity-violating […]

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Subaru High-$z$ Exploration of Low-Luminosity Quasars (SHELLQs). XXV. Large-scale environments of low-luminosity quasars at $zsim6$ traced by Ly$α$ emitters

Posted by klaurent February 12, 2026Tokyo

Kavli Affiliate: John Silverman | Summary:High-$z$ quasars are believed to reside in massive dark matter haloes (DMHs), suggesting that they reside in galaxy overdense regions. However, previous observations have shown a range of environments around them. These fields have been limited to luminous quasars ($M_1450lesssim-25$), for which photoevaporation may hinder galaxy formation in their vicinity. […]

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Subaru High-$z$ Exploration of Low-Luminosity Quasars (SHELLQs). XXV. Large-scale environments of low-luminosity quasars at $zsim6$ traced by Ly$α$ emitters

Posted by klaurent February 12, 2026February 23, 2026Tokyo

Kavli Affiliate: John Silverman | Summary:High-$z$ quasars are believed to reside in massive dark matter haloes (DMHs), suggesting that they reside in galaxy overdense regions. However, previous observations have shown a range of environments around them. The previous targets are limited to bright quasars ($M_1450lesssim-25$), for which photoevaporation may hinder galaxy formation in their vicinity. […]

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Numerical simulation of the stochastic formalism including non-Markovianity

Posted by klaurent February 12, 2026February 23, 2026Tokyo

Kavli Affiliate: Masahiro Kawasaki | Summary:We numerically investigate stochastic dynamics in cosmology by solving Langevin equations for Infrared (IR) modes with stochastic noises generated by Ultraviolet (UV) modes at the coarse-graining scale. By construction, the stochastic formalism relies on the separation of scales, which requires solving the equations for UV modes on top of the […]

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Graded anisotropic metamaterials for elastic wave mode conversion

Posted by klaurent February 12, 2026Caltech

Kavli Affiliate: Chiara Daraio | Summary:Efficient transmission of elastic waves across interfaces is central to several applications, including medical imaging, seismic isolation, and transducer design. Interfaces with abrupt changes in the material properties significantly impede wave transmission, leading to reflections. This limitation, known as impedance mismatch, becomes even more prominent for mode conversion between different […]

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Distinct spatial and non-spatial response properties of excitatory narrow-spike and burst-firing neurons in the marmoset auditory cortex

Posted by dbos February 11, 2026February 23, 2026Hopkins

Kavli Affiliate: Xiaoqin Wan | Authors: Chenggang Chen, Evan D Remington and Xiaoqin Wang | Summary: Cell types are the basic units of the cerebral cortex. Broad and narrow spike waveforms (BW and NW) are the primary criteria for classifying putative excitatory and inhibitory cortical neurons, particularly in non-human primates where genetic accessibility is limited. […]

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Measurement prospects for the pair-instability mass cutoff with gravitational waves

Posted by klaurent February 11, 2026MIT

Kavli Affiliate: Salvatore Vitale | Summary:Pair-instability supernovae leave behind no compact remnants, resulting in a predicted gap in the distribution of stellar black-hole masses. Gravitational waves from binary black-hole mergers probe the relevant mass range and analyses of the LIGO-Virgo-KAGRA catalog (GWTC-4) indicate a possible mass cutoff at $40$-$50,M_odot$. However, the robustness of this result […]

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Measurement prospects for the pair-instability mass cutoff with gravitational waves

Posted by klaurent February 11, 2026MIT

Kavli Affiliate: Salvatore Vitale | Summary:Pair-instability supernovae leave behind no compact remnants, resulting in a predicted gap in the distribution of stellar black-hole masses. Gravitational waves from binary black-hole mergers probe the relevant mass range and analyses of the LIGO-Virgo-KAGRA catalog (GWTC-4) indicate a possible mass cutoff at $40$-$50M_odot$. However, the robustness of this result […]

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