A5103125655- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Astronomical Observations and Instrumentation
- Calibration and Measurement Techniques
- Gaussian Processes and Bayesian Inference
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Statistical and numerical algorithms
University of Portsmouth
2023-2025
The University of Sydney
2025
ABSTRACT The ΛCDM paradigm successfully explains the large-scale structure of Universe, but is less well constrained on subgalactic scales. Gravitational lens modelling has been used to measure imprints dark substructures lensed arcs, testing small-scale predictions ΛCDM. However, methods required for these tests are subject degeneracies among mass model and source light profile. We present a case study unique compound gravitational SDSSJ0946+1006, wherein dark, massive substructure...
ABSTRACT We investigate the ability of human ‘expert’ classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. recruited a total 55 people that completed more than 25 per cent project. During classification task, we present participants 1489 images. The sample contains variety data including simulations, real lenses, non-lens examples, and unlabelled data. find experts are extremely good at finding bright, well-resolved Einstein rings, while arcs with...
Abstract The time delay between multiple images of strongly lensed quasars has been used to infer the Hubble constant. primary systematic uncertainty for time-delay cosmography is mass-sheet transform (MST), which preserves lensing observables while altering inferred H0. TDCOSMO collaboration velocity dispersion measurements and galaxies that mass sheets are present, decrease H0 by 8%. Here, we test assumption density profiles galaxy-galaxy galaxy-quasar lenses same. We use a composite...
Abstract The nature of dark matter is poorly constrained on subgalactic scales. Alternative models to cold matter, such as warm or self-interacting could produce very different haloes these One the few known smaller than a galaxy was discovered in triple source plane strong lens system J0946+1006. Previous studies have found that this structure much more concentrated expected ΛCDM, but assumed halo at same redshift main deflector (zmain = 0.222). In paper, we fit for halo. We reconstruct...
The $\Lambda$CDM paradigm successfully explains the large-scale structure of Universe, but is less well constrained on sub-galactic scales. Gravitational lens modelling has been used to measure imprints dark substructures lensed arcs, testing small-scale predictions $\Lambda$CDM. However, methods required for these tests are subject degeneracies among mass model and source light profile. We present a case study unique compound gravitational SDSSJ0946+1006, wherein dark, massive substructure...
The time delay between multiple images of strongly lensed quasars has been used to infer the Hubble constant. primary systematic uncertainty for time-delay cosmography is mass-sheet transform (MST), which preserves lensing observables while altering inferred $H_0$. TDCOSMO collaboration velocity dispersion measurements and galaxies that mass sheets are present, decrease $H_0$ by 8$\%$. Here, we test assumption density profiles galaxy-galaxy galaxy-quasar lenses same. We use a composite...
The nature of dark matter is poorly constrained on subgalactic scales. Alternative models to cold matter, such as warm or self-interacting could produce very different haloes these One the few known smaller than a galaxy was discovered in triple source plane strong lens system J0946+1006. Previous studies have found that this structure much more concentrated expected $\Lambda$CDM, but assumed halo at same redshift main deflector ($z_{\rm main}=0.222$). In paper, we fit for halo. We...
We investigate the ability of human 'expert' classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. recruited a total 55 people that completed more than 25$\%$ project. During classification task, we present participants 1489 images. The sample contains variety data including simulations, real lenses, non-lens examples, and unlabeled data. find experts are extremely good at finding bright, well-resolved Einstein rings, whilst arcs with $g$-band...