19 citations · 50 across the 18 of their papers we have counts for
12 papers · 1 filter
Model independent lensing sub-structure detection with multiply-imaged star clusters constellations
Leo W. H. Fung, Tom Broadhurst, Sung Kei Li +3
A broad class of dark matter (DM) models predicts the existence of sub-structures residing in DM haloes on sub-resolvable angular scales. Techniques to extract such a generic featu…
Gravitational Lensing Predictions from Wave Simulations of Fuzzy Dark Matter
Jiajun Zhou, Zhengxiang Li, Amruth Alfred +3
In the cold dark matter paradigm, ultra-light particles are emerging as strong contenders to conventional massive particles. A unique prediction of dark matter comprising such ultr…
The Subversive Role of Excessive External Shear in Concealing Lensing Anomalies
Amruth Alfred, Shashpal Singh, Rommulus Francis Lewis +5
To best reproduce observed multiply-lensed lensed images, lens models usually incorporate shear attributed to objects unrelated to the lensing galaxy (i.e., external shear): whethe…
Lensed stars in galaxy-galaxy strong lensing -- a JWST prediction for the Cosmic Horseshoe
Sung Kei Li, Luke Weisenbach, Thomas E. Collett +10
We explore for the first time the possibility of detecting lensed star transients in galaxy-galaxy strong lensing systems upon repeated, deep imaging using the {\it James-Webb Spac…
Magnification bias reveals severe contamination in Hubble Frontier Field photo-z catalogs
Jiashuo Zhang, Jeremy Lim, Tom Broadhurst +4
Gravitational lensing by massive galaxy clusters enables faint distant galaxies to be more abundantly detected than in blank fields, thereby allowing one to construct galaxy lumino…
Signatures of Fuzzy Dark Matter Inside Radial Critical Curves
J. M. Palencia, Paloma Morilla, Sung Kei Li +5
We investigate the strong gravitational lensing properties of fuzzy dark matter (FDM) halos, focusing on the magnification properties near radial critical curves (CCs). Using simul…
Transient star B/R ratio and star formation in lensed galaxies
Sung Kei Li, Jose M. Palencia, Jose M. Diego +8
The extreme magnification from galaxy clusters and microlenses therein allows the detection of individual, luminous stars in lensed galaxies as transient events, and hence provides…
Multi-copy Axion Transfer Function and Observational Implications of Effective de Broglie Scales
Jiashuo Zhang, Tom Broadhurst, Jeremy Lim +2
Ultra-light axions are viable fuzzy/wave-like dark matter (DM) candidates generically predicted by the String Axiverse paradigm with multiple particle copies, whereas most of th…
A high-resolution view of the source-plane magnification near cluster caustics in wave dark matter models
Jose M. Diego, Alfred Amruth, Jose M. Palencia +10
We present the highest resolution images to date of caustics formed by wave dark matter (DM) fluctuations near the critical curves of cluster gravitational lenses. We describe t…
Dark Matter distinguished by skewed microlensing in the "Dragon Arc"
Tom Broadhurst, Sung Kei Li, Amruth Alfred +18
Microlensed stars recently discovered by JWST & HST follow closely the winding critical curve of A370 along all sections of the ``Dragon Arc" traversed by the critical curve. These…
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…
Flashlights: Transients among Gravitationally-Lensed Star Clusters in the Dragon Arc. I. Stellar Microlensing vs Stellar Outbursts
Sung Kei Li, Jose M. Diego, Patrick L. Kelly +8
We report the discovery of transients among star clusters in a distant galaxy that is gravitationally lensed by a foreground galaxy cluster, and explore whether these transients co…