A5045401377- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Statistical and numerical algorithms
- Machine Learning in Materials Science
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Neural Networks and Applications
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- Pulsars and Gravitational Waves Research
- Computational Physics and Python Applications
- Seismology and Earthquake Studies
- Inorganic Fluorides and Related Compounds
- Gaussian Processes and Bayesian Inference
- Space Exploration and Technology
- earthquake and tectonic studies
- Calibration and Measurement Techniques
- Text and Document Classification Technologies
- demographic modeling and climate adaptation
- Seismic Imaging and Inversion Techniques
Perimeter Institute
2024-2025
Institute for Advanced Study
2023-2024
Albert Einstein College of Medicine
2024
Johns Hopkins University
2019-2023
École Normale Supérieure - PSL
2023
Abstract As weak lensing surveys go deeper, there is an increasing need for reliable characterization of non-Gaussian structures at small angular scales. Here we present the first cosmological constraints with scattering transform, a statistical estimator that combines efficiency, robustness, and interpretability. With Hyper Suprime-Cam survey (HSC) year 1 data, obtain Ω m = 0.29 -0.03 +0.04 , S 8 ≡ σ (Ω /0.3) 0.5 0.83±0.02, intrinsic alignment strength A IA 1.0±0.4 through simulation-based...
Parameter estimation with non-Gaussian stochastic fields is a common challenge in astrophysics and cosmology. In this paper, we advocate performing task using the scattering transform, statistical tool sharing ideas convolutional neural networks (CNNs) but requiring no training nor tuning. It generates compact set of coefficients, which can be used as robust summary statistics for information. especially suited presenting localized structures hierarchical clustering, such cosmological...
Recent cosmic shear studies have shown that higher-order statistics (HOS) developed by independent teams now outperform standard two-point estimators in terms of statistical precision thanks to their sensitivity the non-Gaussian features large-scale structure. The aim Higher-Order Weak Lensing Statistics (HOWLS) project is assess, compare, and combine constraining power ten different HOS on a common set $Euclid$-like mocks, derived from N-body simulations. In this first paper HOWLS series,...
ABSTRACT We present cosmological constraints derived from peak counts, minimum and the angular power spectrum of Subaru Hyper Suprime-Cam first-year (HSC Y1) weak lensing shear catalogue. Weak counts contain non-Gaussian information hence are complementary to conventional two-point statistics in constraining cosmology. In this work, we forward-model three summary their dependence on cosmology, using a suite N-body simulations tailored HSC Y1 data. investigate systematic astrophysical effects...
Abstract Cooling white dwarfs (WDs) can yield accurate ages when theoretical cooling models fully account for the physics of dense plasma WD interiors. We use MESA to investigate a set massive and ultramassive WDs (0.9–1.3 <?CDATA ${M}_{\odot }$?> ) which previous have failed match kinematic age indicators based on Gaia DR2. find that in this population be explained as C/O cores experiencing unexpectedly rapid 22 Ne sedimentation strongly liquid interior just prior crystallization. propose...
Abstract Double white dwarf (double-WD) binaries may merge within a Hubble time and produce high-mass WDs. Compared to other WDs, the double-WD merger products have higher velocity dispersion because they are older. With power of Gaia data, we show strong evidence for among WDs by analyzing transverse-velocity distribution more than 1000 (0.8–1.3 M ⊙ ). We estimate that fraction in our sample is about 20%. also obtain precise rate its mass dependence. Our estimates close binary population...
As weak lensing surveys become deeper, they reveal more non-Gaussian aspects of the convergence field which can only be extracted using statistics beyond power spectrum. In Cheng et al. (2020) we showed that scattering transform, a novel statistic borrowing mathematical concepts from convolutional neural networks, is powerful tool for cosmological parameter estimation in regime. Here, extend analysis to explore its sensitivity dark energy and neutrino mass parameters with surveys. We first...
White dwarf stars are the most common end point of stellar evolution. Of special interest ultramassive white dwarfs, as they related to type Ia Supernovae explosions, merger events, and Fast Radio Bursts. Ultramassive dwarfs expected harbour oxygen-neon (ONe) cores a result single standard However, fraction them could have carbon-oxygen (CO) cores. Recent studies, based on new observations provided by {\it Gaia} space mission, indicate that small experience strong delay in their cooling,...
Abstract Galactic short-period close white dwarf binaries (CWDBs) are important objects for space-borne gravitational-wave (GW) detectors in the millihertz frequency bands. Due to intrinsically low luminosity, only about 25 identified CWDBs detectable by Laser Interferometer Space Antenna (LISA), which also known as verification (VBs). The Gaia Early Data Release 3 (EDR3) provids a catalog containing large number of CWDB candidates, includes parallax and photometry measurements. We...
Recently, the power of Gaia data has revealed an enhancement high-mass white dwarfs (WDs) on Hertzsprung--Russell diagram, called Q branch. This branch is located at end recently identified crystallization Investigating its properties, we find that number density and velocity distribution cannot be explained by cooling delay alone, suggesting existence extra delay. To quantify this delay, statistically compare two age indicators -- dynamical inferred from transverse velocity, photometric...
While it is well established that giant-planet occurrence rises rapidly with host star metallicity, not yet clear if small-planet around late-type dwarf stars depends on metallicity. Using the Kepler Data Release 25 planet candidate list and its completeness data products, we explore as a function of metallicity in field's stellar population. We find increases for all radii $R_{\mathrm{p}}$ down to at least $R_{\mathrm{p}}\approx2~R_{\oplus}$ range $2~R_{\oplus}\lesssim...
Abstract The mass–radius relation of white dwarfs is largely determined by the equation state degenerate electrons, which causes stellar radius to decrease as mass increases. Here we observationally measure this using gravitational redshift effect, a prediction general relativity that depends on ratio between and radius. Using observations over 3000 from Sloan Digital Sky Survey Gaia space observatory, derive apparent radial velocities absorption lines, radii photometry parallaxes, surface...
Physicists routinely need probabilistic models for a number of tasks such as parameter inference or the generation new realizations field. Establishing highly non-Gaussian fields is challenge, especially when samples limited. In this paper, we introduce scattering spectra stationary and show that they provide accurate robust statistical descriptions wide range encountered in physics. These are based on covariances coefficients, i.e. wavelet decomposition field coupled with pointwise modulus....
Aims. With the next generation of large surveys coming to stage observational cosmology soon, it is important explore their potential synergies and maximise scientific outcomes. In this study, we aim investigate complementarity two upcoming space missions Euclid China Space Station Telescope (CSST), focusing on weak lensing (WL) cosmology. particular, analyse photometric redshifts (photo-zs) galaxy blending effects. For Euclid, WL measurements suffer from chromatic PSF this, CSST can provide...
ABSTRACT We infer the dynamical masses of stars across Hertzsprung–Russell (H–R) diagram using wide binaries from Gaia survey. Gaia’s high-precision astrometry measures binaries’ orbital motion, which contains mass information. Using as training sample, we measure 2D H–R combination statistical inference and neural networks. Our results provide measurements for main-sequence 0.1 to 2 M⊙, unresolved binaries, triples on main sequence, mean giants white dwarfs. Two regions in show interesting...
As weak lensing surveys go deeper, there is an increasing need for reliable characterization of non-Gaussian structures at small angular scales. Here we present the first cosmological constraints with scattering transform, a statistical estimator that combines efficiency, robustness, and interpretability. With Hyper Suprime-Cam survey (HSC) year 1 data, obtain $\Omega_\text{m}=0.29_{-0.03}^{+0.04}$, $S_8\equiv \sigma_8(\Omega_\text{m}/0.3)^{0.5}=0.83\pm0.02$, intrinsic alignment strength...
Extracting information from stochastic fields or textures is a ubiquitous task in science, exploratory data analysis to classification and parameter estimation. From physics biology, it tends be done either through power spectrum analysis, which often too limited, the use of convolutional neural networks (CNNs), require large training sets lack interpretability. In this paper, we advocate for scattering transform (Mallat 2012), powerful statistic borrows mathematical ideas CNNs but does not...
We present cosmological constraints derived from peak counts, minimum and the angular power spectrum of Subaru Hyper Suprime-Cam first-year (HSC Y1) weak lensing shear catalog. Weak counts contain non-Gaussian information hence are complementary to conventional two-point statistics in constraining cosmology. In this work, we forward-model three summary their dependence on cosmology, using a suite $N$-body simulations tailored HSC Y1 data. investigate systematic astrophysical effects...
Baryonic feedback is a major systematic in weak lensing cosmology. Its most studied effect the suppression of power spectrum, second-order statistic, on small scales. Motivated by growing interest statistics beyond second order, we investigate baryons non-Gaussian and resulting biases matter clustering amplitude $S_8 = \sigma_8\sqrt{\Omega_m/0.3}$. We focus Subaru Hyper Suprime-Cam Year 1 (HSC-Y1) data which, with its high source number density, closely resembles those expected from upcoming...