Local Analogs of Little Red Dots: Clues to the X-ray Weakness

Kavli Affiliate: Luis Ho | Summary:A major question about JWST’s little red dots (LRDs) at $zsim4-8$ is the origin of their apparent X-ray weakness. Even deep Chandra stacks yield only tentative detections or broad-band limits and cannot distinguish among super-Eddington accretion, intrinsic X-ray weakness, and Compton-thick (CT) obscuration. Local analogs offer a powerful complementary route. […]


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Nuclear Millimeter Continuum Emission in Radio-Quiet Active Galactic Nuclei: an ALMA Spectral and Variability Study

Kavli Affiliate: Claudio Ricci | Summary:Unresolved millimeter (mm) emission is observed in radio-quiet (RQ) Active Galactic Nuclei (AGN), but its physical origin remains debated. Self-absorbed synchrotron emission from the compact X-ray corona is one of the leading candidates. Previous support for this coronal synchrotron origin has mainly been based on variability and spectral indices in […]


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Boot-AVT: Asymptotically Anytime-Valid Testing with Degenerate U-Statistics via Bootstrap

Kavli Affiliate: Feng Long| Summary: Many nonparametric tests are based on $U$-statistics that are degenerate under the null hypothesis. We develop Boot-AVT, a bootstrap procedure for asymptotically anytime-valid testing with these statistics. Using Brownian scaling and time inversion for the limiting Gaussian chaos process, we show that logarithmically penalized maxima over observed and future sample […]


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Mid-infrared Imaging of SR 12 c with JWST/MIRI: Grain Growth in an Evolved Circumplanetary Disk

Kavli Affiliate: Gregory Herczeg | Summary:The physical properties of circumplanetary disks offer insights into the formation of giant planets and their satellites. The circumbinary planetary-mass companion SR 12 c (1200 au from SR 12 AB) hosts an isolated dust disk directly detected with ALMA. We present JWST/MIRI imaging of SR 12 c from 5.6 to […]


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Dynamic Programming for Value-at-risk Markov Decision Processes in Continuous Spaces

Kavli Affiliate: Xian Chen| Summary: Value-at-Risk (VaR) is a widely adopted quantile-based risk measure in practice, yet incorporating VaR objectives into Markov decision processes (VaR MDPs) remains a longstanding challenge. Recent work has derived dynamic programming equations for VaR MDPs in finite state and action spaces but left the case of more general spaces unresolved. […]


Continue.. Dynamic Programming for Value-at-risk Markov Decision Processes in Continuous Spaces

Dynamic Programming for Value-at-Risk Markov Decision Processes in Continuous Spaces

Kavli Affiliate: Xian Chen| Summary: Value-at-Risk (VaR) is a widely adopted quantile-based risk measure in practice, yet incorporating VaR objectives into Markov decision processes (VaR MDPs) remains a longstanding challenge. Recent work has derived dynamic programming equations for VaR MDPs in finite state and action spaces but left the case of more general spaces unresolved. […]


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Probing fundamental physics with ALMA2040 mm-wavelength observations of neutron stars

Kavli Affiliate: Lijing Shao | Summary:Bursty or (rotation-induced) pulsed coherent radio emission from pulsars, magnetars, and fast radio transients originates in some of the most extreme environments in the Universe. However, the exact physical mechanism behind the scenes remains poorly understood. ALMA2040 will allow for systematic exploration of the millimeter-wavelength spectral window for pulsars and […]


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An Attenuation Bump at z=9.3: Probing Dust Diversity at Cosmic Dawn

Kavli Affiliate: Kohei Inayoshi | Summary:We report the identification of a UV attenuation bump in the Black Pearl, a galaxy at a spectroscopic redshift of 9.3335 observed with JWST/NIRSpec as part of the ZENITH and EMBER surveys. This is the highest-redshift UV bump reported to date, probing dust properties only approximately 500 Myr after the […]


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How Little Red Dots Turn Blue: Evolution of Kelvin-Helmholtz Contracting Black Hole Envelopes and Observational Diagnostics

Kavli Affiliate: Kohei Inayoshi | Summary:James Webb Space Telescope (JWST) observations have revealed compact, red-colored, broad-line emitters known as little red dots (LRDs), while a bluer counterpart population has been referred to as little blue dots (LBDs). Their physical connection remains unclear: they may represent different evolutionary stages of the same phenomenon, distinct populations, or […]


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A Step-Like Transition Underlying the Life and Death of Galaxies

Kavli Affiliate: Luis Ho | Summary:How galaxies stop forming stars is a complex and central problem in astrophysics. Numerous physical mechanisms have been proposed, yet a simple, unified framework connecting these mechanisms remains lacking. Here, we derive a step-function quenching response from the fundamental principle of gas mass conservation, governed by the competition between gas-supply […]


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