Publications (52)
Self-Interacting Dark Matter, Core Collapse and the Galaxy-Galaxy Strong Lensing Discrepancy
Isaque Dutra, Priyamvada Natarajan, Daniel Gilman
Gravitational lensing by galaxy clusters has emerged as a powerful tool to probe the standard Cold Dark Matter (CDM) paradigm of structure formation in the Universe. Despite the re…
Strong lensing constraints on primordial black holes as a dark matter candidate
Veronica Dike, Daniel Gilman, Tommaso Treu
Dark matter could comprise, at least in part, primordial black holes (PBH). To test this hypothesis, we present an approach to constrain the PBH mass () and mass frac…
Probing the nature of dark matter by forward modeling flux ratios in strong gravitational lenses
Daniel Gilman, Simon Birrer, Tommaso Treu +2
The free streaming length of dark matter particles determines the abundance of structure on sub-galactic scales. We present a statistical technique, amendable to any parameterizati…
Testing the Nature of Dark Matter with Extremely Large Telescopes
Joshua D. Simon, Simon Birrer, Keith Bechtol +12
For nearly 40 years, dark matter has been widely assumed to be cold and collisionless. Cold dark matter models make fundamental predictions for the behavior of dark matter on small…
Core collapse in resonant self-interacting dark matter across two decades in halo mass
Vinh Tran, Xuejian Shen, Daniel Gilman +5
Core collapse, a process associated with self-interacting dark matter (SIDM) models, can increase the central density of halos by orders of magnitude with observable consequences f…
Turbocharging constraints on dark matter substructure through a synthesis of strong lensing flux ratios and extended lensed arcs
Daniel Gilman, Simon Birrer, Anna Nierenberg +1
Strong gravitational lensing provides a purely gravitational means to infer properties of dark matter halos and thereby constrain the particle nature of dark matter. Strong lenses…
Generating Dark Matter Subhalo Populations Using Normalizing Flows
Jack Lonergan, Andrew Benson, Daniel Gilman
Strong gravitational lensing is a powerful tool for probing the nature of dark matter, as lensing signals are sensitive to the dark matter substructure within the lensing galaxy. W…
Role of prompt cusps in driving the core collapse of SIDM halos
Vinh Tran, Daniel Gilman, M. Sten Delos +4
Prompt cusps (PCs) form from the direct collapse of overdensities in the early Universe, reside at the center of every dark matter halo, and have density profiles steeper than $r^{…
Elliptical multipoles for gravitational lenses
Hadrien Paugnat, Daniel Gilman
Gravitational lensing galaxies are commonly modeled with elliptical density profiles, to which angular complexity is sometimes added through a multipole expansion - encoding deform…
Constraints on the mass-concentration relation of cold dark matter halos with 11 strong gravitational lenses
Daniel Gilman, Xiaolong Du, Andrew Benson +3
The mass-concentration relation of dark matter halos reflects the assembly history of objects in hierarchical structure formation scenarios, and depends on fundamental quantities i…
The Magnificent Five Images of Supernova Refsdal: Time Delay and Magnification Measurements
Patrick L. Kelly, Steven Rodney, Tommaso Treu +28
In late 2014, four images of Supernova (SN) "Refsdal," the first known example of a strongly lensed SN with multiple resolved images, were detected in the MACS J1149 galaxy-cluster…
The primordial matter power spectrum on sub-galactic scales
Daniel Gilman, Andrew Benson, Jo Bovy +3
The primordial matter power spectrum quantifies fluctuations in the distribution of dark matter immediately following inflation. Over cosmic time, over-dense regions of the primord…
Gravothermal Catastrophe in Resonant Self-interacting Dark Matter Models
Vinh Tran, Daniel Gilman, Mark Vogelsberger +3
We investigate a self-interacting dark matter (SIDM) model featuring a velocity-dependent cross section with an order-of-magnitude resonant enhancement of the cross section at $\si…
Macromodel-free flux-ratio prediction in quadruply imaged quasars with local constraints from lensed arcs
Hadrien Paugnat, Tommaso Treu, Daniel Gilman
Strong gravitational lensing is a powerful cosmological probe, providing a direct tool to unveil the properties of dark matter (DM) on sub-galactic scales. In particular, flux-rati…
Tidal evolution of cored and cuspy dark matter halos
Xiaolong Du, Andrew Benson, Zhichao Carton Zeng +9
The internal structure and abundance of dark matter halos and subhalos are powerful probes of the nature of dark matter. In order to compare observations with dark matter models, a…
TDCOSMO 2025: Cosmological constraints from strong lensing time delays
TDCOSMO Collaboration, Simon Birrer, Elizabeth J. Buckley-Geer +30
We present cosmological constraints from 8 strongly lensed quasars (hereafter, the TDCOSMO-2025 sample). Building on previous work, our analysis incorporated new deflector stellar…
Faster than SAM: An empirical model for the tidal evolution of dark matter substructure around strong gravitational lenses
Xiaolong Du, Daniel Gilman, Tommaso Treu +2
Strong gravitational lenses enable direct inference of halo abundance and internal structure, which in turn enable constraints on the nature of dark matter and the primordial matte…
Snowmass2021 Cosmic Frontier White Paper: Cosmological Simulations for Dark Matter Physics
Arka Banerjee, Kimberly K. Boddy, Francis-Yan Cyr-Racine +15
Over the past several decades, unexpected astronomical discoveries have been fueling a new wave of particle model building and are inspiring the next generation of ever-more-sophis…
Probing dark matter structure down to solar masses: flux ratio statistics in gravitational lenses with line of sight halos
Daniel Gilman, Simon Birrer, Tommaso Treu +2
Strong lensing provides a powerful means of investigating the nature of dark matter as it probes dark matter structure on sub-galactic scales. We present an extension of a forward…
HST imaging, pipeline modeling, and time-delay predictions of 2 triply-imaged and 15 quadruply-imaged lensed quasars
William Sheu, Tommaso Treu, Adriano Agnello +9
The Hubble-Lema\^ıtre tension remains a significant challenge in modern cosmology, exhibiting a discrepancy between early-Universe cosmic microwave background measurements and loca…
SN 2022riv in RX J2129: Discovery, Spectroscopic Classification, and Microlensing of a Strongly Lensed Type Ia Supernova from JWST and HST Observations
Birendra Dhanasingham, Patrick L. Kelly, Wenlei Chen +27
The multiply imaged SN 2022riv was discovered through a search of galaxy cluster fields as part of a Hubble Space Telescope (HST) SNAP program to find highly magnified stars. The s…
Neural posterior estimation of the line-of-sight and subhalo populations in galaxy-scale strong lensing systems
Birendra Dhanasingham, Francis-Yan Cyr-Racine, Daniel Gilman
Strong gravitational lensing is a powerful probe for studying the fundamental properties of dark matter on sub-galactic scales. Detailed analyses of galaxy-scale lenses have reveal…
Strong lensing signatures of self-interacting dark matter in low-mass halos
Daniel Gilman, Jo Bovy, Tommaso Treu +4
Core formation and runaway core collapse in models with self-interacting dark matter (SIDM) significantly alter the central density profiles of collapsed halos. Using a forward mod…
LensWatch. II. Improved Photometry and Time-delay Constraints on the Strongly Lensed Type Ia Supernova 2022qmx ("SN Zwicky") with HST Template Observations
Conor Larison, Justin D. R. Pierel, Max J. B. Newman +34
Strongly lensed supernovae (SNe) are a rare class of transient that can offer tight cosmological constraints that are complementary to methods from other astronomical events. We pr…
Constraints on sterile neutrino models from strong gravitational lensing, Milky Way satellites, and Lyman- forest
Ioana A. Zelko, Tommaso Treu, Kevork N. Abazajian +5
The nature of dark matter is one of the most important unsolved questions in science. Some dark matter candidates do not have sufficient nongravitational interactions to be probed…
Warm dark matter chills out: constraints on the halo mass function and the free-streaming length of dark matter with 8 quadruple-image strong gravitational lenses
Daniel Gilman, Simon Birrer, Anna Nierenberg +3
The free-streaming length of dark matter depends on fundamental dark matter physics, and determines the abundance and concentration of dark matter halos on sub-galactic scales. Usi…
Report of the Topical Group on Cosmic Probes of Dark Matter for Snowmass 2021
Alex Drlica-Wagner, Chanda Prescod-Weinstein, Hai-Bo Yu +37
Cosmological and astrophysical observations currently provide the only robust, positive evidence for dark matter. Cosmic probes of dark matter, which seek to determine the fundamen…
JWST Lensed quasar dark matter survey II: Strongest gravitational lensing limit on the dark matter free streaming length to date
Ryan E. Keeley, Anna M. Nierenberg, Daniel Gilman +20
This is the second in a series of papers in which we use JWST MIRI multiband imaging to measure the warm dust emission in a sample of 31 multiply imaged quasars, to be used as a pr…
Dark Galactic subhalos and the Gaia snail
Daniel Gilman, Jo Bovy, Neige Frankel +1
Gaia has revealed a clear signal of disequilibrium in the solar neighborhood in the form of a spiral (or snail) feature in the vertical phase-space distribution. We investigate the…
Strong lensing signatures of luminous structure and substructure in early-type galaxies
Daniel Gilman, Adriano Agnello, Tommaso Treu +2
The arrival times, positions, and fluxes of multiple images in strong lens systems can be used to infer the presence of dark subhalos in the deflector, and thus test predictions of…
Interlopers speak out: studying the dark universe using small-scale lensing anisotropies
Birendra Dhanasingham, Francis-Yan Cyr-Racine, Annika H. G. Peter +2
Strongly lensed systems are powerful probes of the distribution of dark matter on small scales. In this paper, we show that line-of-sight haloes between the source and the observer…
Joint Semi-Analytic Multipole Priors from Galaxy Isophotes and Constraints from Lensed Arcs
Maverick S. H. Oh, Anna Nierenberg, Daniel Gilman +1
Flux-ratio anomalies in quadruply imaged quasars are sensitive to the imprint of low-mass dark-matter haloes. The reliability of detection depends on the robustness of the smooth m…
Dark Matter Substructure: A Lensing Perspective
Charles Gannon, Anna Nierenberg, Andrew Benson +3
The study of dark matter substructure through strong gravitational lensing has shown enormous promise in probing the properties of dark matter on sub-galactic scales. This approach…
Dents in the Mirror: A Novel Probe of Dark Matter Substructure in Galaxy Clusters from the Astrometric Asymmetry of Lensed Arcs
Derek Perera, Daniel Gilman, Liliya L. R. Williams +5
Astrometric perturbations of lensed arcs behind galaxy clusters have been recently suggested as promising probes of small-scale () dark matter substructure.…
LSST Strong Lensing Systems Dark Matter Sensitivity Analysis with Neural Ratio Estimators
Andreas Filipp, Yashar Hezaveh, Laurence Perreault-Levasseur +2
Strong gravitational lensing offers a unique probe of dark matter (DM) on sub-galactic scales, where the abundance and distribution of low-mass halos are highly sensitive to the un…
Novel density profile for isothermal cores of dark matter halos
Vinh Tran, Xuejian Shen, Mark Vogelsberger +5
We present a novel analytic density profile for halos in self-interacting dark matter (SIDM) models, which accurately captures the isothermal-core configuration, i.e. where both th…
TDCOSMO III: Dark matter substructure meets dark energy -- the effects of (sub)halos on strong-lensing measurements of
Daniel Gilman, Simon Birrer, Tommaso Treu
Time delay cosmography uses the arrival time delays between images in strong gravitational lenses to measure cosmological parameters, in particular the Hubble constant . The l…
Constraining the Physical Properties of Quadruply Lensed Quasars using Optical-to-X-Ray Data
Kriti Kamal Gupta, Dominique Sluse, Maarten Baes +5
Gravitational lensing of luminous active galactic nuclei (AGN; or quasars) can be used as a natural telescope to zoom in on their inner structures. With more and more lensed AGN be…
JWST Spectroscopy of SN H0pe: Classification and Time Delays of a Triply-imaged Type Ia Supernova at z = 1.78
Wenlei Chen, Patrick L. Kelly, Brenda L. Frye +19
SN H0pe is a triply imaged supernova (SN) at redshift discovered using the James Webb Space Telescope (JWST). In order to classify the SN spectroscopically and measure the…
Statistical imprints of wave-like dark matter on multiply-imaged galaxies in strong cluster lenses from JWST
Nino Ephremidze, Daniel Gilman, Cora Dvorkin
Wave-like dark matter (DM) is an elusive dark matter (DM) candidate. The model, often also called fuzzy or ultralight DM, proposes that DM is an extremely light ($m\sim10^{-22}…
Time Delay Lens Modeling Challenge: I. Experimental Design
Xuheng Ding, Tommaso Treu, Anowar J. Shajib +11
Strong gravitational lenses with measured time delay are a powerful tool to measure cosmological parameters, especially the Hubble constant (). Recent studies show that by com…
Constraints on the Hubble constant from Supernova Refsdal's reappearance
Patrick L. Kelly, Steven Rodney, Tommaso Treu +27
The gravitationally lensed Supernova Refsdal appeared in multiple images, produced through gravitational lensing by a massive foreground galaxy cluster. After the supernova appeare…
Snowmass2021 Cosmic Frontier White Paper: Dark Matter Physics from Halo Measurements
Keith Bechtol, Simon Birrer, Francis-Yan Cyr-Racine +41
The non-linear process of cosmic structure formation produces gravitationally bound overdensities of dark matter known as halos. The abundances, density profiles, ellipticities, an…
Constraining resonant dark matter self-interactions with strong gravitational lenses
Daniel Gilman, Yi-Ming Zhong, Jo Bovy
We devise a method to constrain self-interacting dark matter (SIDM) from observations of quadruply-imaged quasars, and apply it to five self-interaction potentials with a long-rang…
First measurement of narrow-line flux ratios for a lensed quasar with JWST/NIRSpec IFS
Hadrien Paugnat, Tommaso Treu, Anna M. Nierenberg +3
Strong gravitational lensing is a powerful probe of dark matter (DM) structure on subgalactic scales: in particular, statistics of flux-ratio anomalies (discrepancies between mass…
lenstronomy II: A gravitational lensing software ecosystem
Simon Birrer, Anowar J. Shajib, Daniel Gilman +18
lenstronomy is an Astropy-affiliated Python package for gravitational lensing simulations and analyses. lenstronomy was introduced by Birrer and Amara (2018) and is based on the li…
Pushing the Limits of Detectability: Mixed Dark Matter from Strong Gravitational Lenses
Ryan E. Keeley, Anna M. Nierenberg, Daniel Gilman +3
One of the frontiers for advancing what is known about dark matter lies in using strong gravitational lenses to characterize the population of the smallest dark matter halos. There…
JAXtronomy: A JAX port of lenstronomy
Alan Huang, Simon Birrer, Daniel Gilman +4
Gravitational lensing is a phenomenon where light bends around massive objects, resulting in distorted images seen by an observer. Studying gravitationally lensed systems provides…
Quantum fluctuations masquerade as halos: Bounds on ultra-light dark matter from quadruply-imaged quasars
Alexander Laroche, Daniel Gilman, Xinyu Li +2
Ultra-light dark matter (ULDM) refers to a class of theories, including ultra-light axions, in which particles with mass comprise a significant fraction…
Imaging dark matter at the smallest scales with lensed stars
J. M. Diego, Sung Kei Li, Alfred Amruth +19
Observations of caustic-crossing galaxies at redshift show a wealth of transient events. Most of them are believed to be microlensing events of highly magnified stars. Ea…
Dark Matter Subhalos and Higher Order Catastrophes in Gravitational Wave Lensing
Luka Vujeva, Jose MarÃa Ezquiaga, Daniel Gilman +2
Gravitational lensing is an invaluable probe of the nature of dark matter, and the structures it forms. Lensed gravitational waves in particular allow for unparalleled sensitivity…
Dark Matter Constraints from a Unified Analysis of Strong Gravitational Lenses and Milky Way Satellite Galaxies
Ethan O. Nadler, Simon Birrer, Daniel Gilman +5
Joint analyses of small-scale cosmological structure probes are relatively unexplored and promise to advance measurements of microphysical dark matter properties using heterogeneou…