Subhalo effective density slope measurements from HST strong lensing data with neural likelihood-ratio estimation

Abstract

Examining the properties of subhalos with strong gravitational lensing images can shed light on the nature of dark matter. From upcoming large-scale surveys, we expect to discover orders of magnitude more strong lens systems that can be used for subhalo studies. To optimally extract information from a large number of strong lensing images, machine learning provides promising avenues for efficient analysis that is unachievable with traditional analysis methods, but application of machine learning techniques to real observations is still limited. We build upon previous work, which uses a neural likelihood-ratio estimator, to constrain the effective density slopes of subhalos and demonstrate the feasibility of this method on real strong lensing observations. To do this, we implement significant improvements to the forward simulation pipeline and undertake careful model evaluation using simulated images. Ultimately, we use our trained model to predict the effective subhalo density slope from combining a set of strong lensing images taken by the \textit{Hubble Space Telescope}. We found the subhalo slope measurement of this set of observations to be steeper than the slope predictions of cold dark matter subhalos. Our result adds to several previous works that also measured high subhalo slopes in observations. Although a possible explanation for this is that subhalos with steeper slopes are easier to detect due to selection effects and thus contribute to statistical bias, our result nevertheless points to the need for careful analysis of more strong lensing observations from future surveys.

arXiv comment11 pages, 6 figures, v2; matches published version in MNRAS

References in corpus (64)

• A Universal Density Profile from Hierarchical Clustering
• Decoupled Weight Decay Regularization
• Observational evidence for self-interacting cold dark matter
• The Cosmic Evolution Survey (COSMOS) -- Overview
• Ellipsoidal collapse and an improved model for the number and spatial distribution of dark matter haloes
• Halo Formation in Warm Dark Matter Models
• Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles
• Cosmological Simulations with Self-Interacting Dark Matter I: Constant Density Cores and Substructure
• The COSMOS Survey: Hubble Space Telescope / Advanced Camera for Surveys (HST/ACS) Observations and Data Processing
• Direct Detection of CDM Substructure
• The properties of warm dark matter haloes
• The Sloan Lens ACS Survey. V. The Full ACS Strong-Lens Sample
• The haloes of bright satellite galaxies in a warm dark matter universe
• The Structural Evolution of Substructure
• Do ImageNet Classifiers Generalize to ImageNet?
• Gravitational detection of a low-mass dark satellite at cosmological distance
• Toward High-Precision Astrometry with WFPC2. I. Deriving an Accurate PSF
• The population of galaxy-galaxy strong lenses in forthcoming optical imaging surveys
• Detection of lensing substructure using ALMA observations of the dusty galaxy SDP.81
• Lenstronomy: multi-purpose gravitational lens modelling software package
• Core Formation in Dwarf Halos with Self Interacting Dark Matter: No Fine-Tuning Necessary
• Detection of a Dark Substructure through Gravitational Imaging
• The Sloan Lens ACS Survey. IX. Colors, Lensing and Stellar Masses of Early-type Galaxies
• Shear and Ellipticity in Gravitational Lenses
• FIRE in the Field: Simulating the Threshold of Galaxy Formation
• There is No Missing Satellites Problem
• Parameterized Machine Learning for High-Energy Physics
• The stellar mass-halo mass relation of isolated field dwarfs: a critical test of $\Lambda$CDM at the edge of galaxy formation
• Inference of the Cold Dark Matter substructure mass function at z=0.2 using strong gravitational lenses
• An excess of small-scale gravitational lenses observed in galaxy clusters
• Gravitational lens modeling with basis sets
• The Third Gravitational Lensing Accuracy Testing (GREAT3) Challenge Handbook
• Fast calculation of a family of elliptical mass gravitational lens models
• A Quantitative Study of Interacting Dark Matter in Halos
• Structure and Subhalo Population of Halos in a Self-Interacting Dark Matter Cosmology
• Approximating Likelihood Ratios with Calibrated Discriminative Classifiers
• Low-mass halo perturbations in strong gravitational lenses at redshift z$\sim$0.5 are consistent with CDM
• Accelerated core collapse in tidally stripped self-interacting dark matter halos
• Lensing substructure quantification in RXJ1131-1231: A 2 keV lower bound on dark matter thermal relic mass
• The structure and evolution of cold dark matter halos
• Measuring the power spectrum of dark matter substructure using strong gravitational lensing
• Discovering New Strong Gravitational Lenses in the DESI Legacy Imaging Surveys
• Precision simulation of ground-based lensing data using observations from space
• Diversity in density profiles of self-interacting dark matter satellite halos
• Mining for Dark Matter Substructure: Inferring subhalo population properties from strong lenses with machine learning
• Core-collapse, evaporation and tidal effects: the life story of a self-interacting dark matter subhalo
• The tidal evolution of dark matter substructure -- II. The impact of artificial disruption on subhalo mass functions and radial profiles
• Probing the nature of dark matter by forward modeling flux ratios in strong gravitational lenses
• Self-Interacting Dark Matter and Small-Scale Gravitational Lenses in Galaxy Clusters
• On the Power Spectrum of Dark Matter Substructure in Strong Gravitational Lenses
• Gravitational Lensing and the Power Spectrum of Dark Matter Substructure: Insights from the ETHOS N-body Simulations
• Substructure Detection Reanalyzed: Dark Perturber shown to be a Line-of-Sight Halo
• A Dark Census: Statistically Detecting the Satellite Populations of Distant Galaxies
• A persistent excess of galaxy-galaxy strong lensing observed in galaxy clusters
• The probability of galaxy-galaxy strong lensing events in hydrodynamical simulations of galaxy clusters
• From Images to Dark Matter: End-To-End Inference of Substructure From Hundreds of Strong Gravitational Lenses
• Probing the small-scale structure in strongly lensed systems via transdimensional inference
• Beyond subhalos: Probing the collective effect of the Universe's small-scale structure with gravitational lensing
• Estimating the warm dark matter mass from strong lensing images with truncated marginal neural ratio estimation
• Inferring the concentration of dark matter subhalos perturbing strongly lensed images
• Extracting the Subhalo Mass Function from Strong Lens Images with Image Segmentation
• Image segmentation for analyzing galaxy-galaxy strong lensing systems
• Quantifying the power spectrum of small-scale structure in semi-analytic galaxies
• Inferring subhalo effective density slopes from strong lensing observations with neural likelihood-ratio estimation

Cited by in corpus (7)

• A Self-interacting Dark Matter Solution to the Extreme Diversity of Low-mass Halo Properties
• Numerical Challenges in Modeling Gravothermal Collapse in Self-Interacting Dark Matter Halos
• Gravothermal collapse and the diversity of galactic rotation curves
• Macromodel-free flux-ratio prediction in quadruply imaged quasars with local constraints from lensed arcs
• Semi-Analytic Modeling of Dark Matter Subhalo Encounters with Thin Stellar Streams: Statistical Predictions for GD-1-like Streams in CDM
• Robustness of Neural Ratio and Posterior Estimators to Distributional Shifts for Population-Level Dark Matter Analysis in Strong Gravitational Lensing
• LSST Strong Lensing Systems Dark Matter Sensitivity Analysis with Neural Ratio Estimators