All Outputs (8)

Lopsidedness in early-type galaxies: the role of the m = 1 multipole in isophote fitting and strong lens modelling (2025)
Journal Article
Amvrosiadis, A., Nightingale, J. W., He, Q., Robertson, A., Lange, S., Frenk, C. S., Cole, S., Massey, R., & Poci, A. (2025). Lopsidedness in early-type galaxies: the role of the m = 1 multipole in isophote fitting and strong lens modelling. Monthly Notices of the Royal Astronomical Society, 540(4), 3281-3288. https://doi.org/10.1093/mnras/staf857

The surface brightness distribution of massive early-type galaxies (ETGs) often deviates from a perfectly elliptical shape. To capture these deviations in their isophotes during an ellipse fitting analysis, Fourier modes of order are often used. In s... Read More about Lopsidedness in early-type galaxies: the role of the m = 1 multipole in isophote fitting and strong lens modelling.

Galaxy mass modelling from multiwavelength JWST strong lens analysis: dark matter substructure, angular mass complexity, or both? (2025)
Journal Article
Lange, S. C., Amvrosiadis, A., Nightingale, J. W., He, Q., Frenk, C. S., Robertson, A., Cole, S., Massey, R., Cao, X., Li, R., & Wang, K. (2025). Galaxy mass modelling from multiwavelength JWST strong lens analysis: dark matter substructure, angular mass complexity, or both?. Monthly Notices of the Royal Astronomical Society, 539(2), 704-726. https://doi.org/10.1093/mnras/staf491

We analyse two galaxy-scale strong gravitational lenses, SPT0418-47 and SPT2147-50, using JWST NIRCam imaging across multiple filters. To account for angular complexity in the lens mass distribution, we introduce multipole perturbations with orders m... Read More about Galaxy mass modelling from multiwavelength JWST strong lens analysis: dark matter substructure, angular mass complexity, or both?.

The onset of bar formation in a massive galaxy at z ∼ 3.8 (2025)
Journal Article
Amvrosiadis, A., Lange, S., Nightingale, J. W., He, Q., Frenk, C. S., Oman, K. A., Smail, I., Swinbank, A. M., Fragkoudi, F., Gadotti, D. A., Cole, S., Borsato, E., Robertson, A., Massey, R., Cao, X., & Li, R. (2025). The onset of bar formation in a massive galaxy at z ∼ 3.8. Monthly Notices of the Royal Astronomical Society, 537(2), 1163-1181. https://doi.org/10.1093/mnras/staf048

We examine the morphological and kinematical properties of SPT-2147, a strongly lensed, massive, dusty, star-forming galaxy at z = 3.762. Combining data from JWST, Hubble Space Telescope, and ALMA, we study the galaxy’s stellar emission, dust continu... Read More about The onset of bar formation in a massive galaxy at z ∼ 3.8.

Unveiling lens light complexity with a novel multi-Gaussian expansion approach for strong gravitational lensing (2024)
Journal Article
He, Q., Nightingale, J. W., Amvrosiadis, A., Robertson, A., Cole, S., Frenk, C. S., Massey, R., Li, R., Cao, X., Lange, S. C., & França, J. P. C. (2024). Unveiling lens light complexity with a novel multi-Gaussian expansion approach for strong gravitational lensing. Monthly Notices of the Royal Astronomical Society, 532(2), 2441-2462. https://doi.org/10.1093/mnras/stae1577

In a strong gravitational lensing system, the distorted light from a source is analysed to infer the properties of the lens. However, light emitted by the lens itself can contaminate the image of the source, introducing systematic errors in the analy... Read More about Unveiling lens light complexity with a novel multi-Gaussian expansion approach for strong gravitational lensing.

Strong gravitational lensing’s ‘external shear’ is not shear (2024)
Journal Article
Etherington, A., Nightingale, J., Massey, R., Tam, S.-I., Cao, X., Niemiec, A., He, Q., Robertson, A., Li, R., Amvrosiadis, A., Cole, S., Diego, J., Frenk, C., Frye, B., Harvey, D., Jauzac, M., Koekemoer, A., Lagattuta, D., Lange, S., Limousin, M., …Steinhardt, C. (2024). Strong gravitational lensing’s ‘external shear’ is not shear. Monthly Notices of the Royal Astronomical Society, 531(3), 3684-3697. https://doi.org/10.1093/mnras/stae1375

The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus ‘external shear’, which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight. A small amount of e... Read More about Strong gravitational lensing’s ‘external shear’ is not shear.

Scanning for dark matter subhaloes in Hubble Space Telescope imaging of 54 strong lenses (2023)
Journal Article
Nightingale, J. W., He, Q., Cao, X., Amvrosiadis, A., Etherington, A., Frenk, C. S., Hayes, R. G., Robertson, A., Cole, S., Lange, S., Li, R., & Massey, R. (2024). Scanning for dark matter subhaloes in Hubble Space Telescope imaging of 54 strong lenses. Monthly Notices of the Royal Astronomical Society, 527(4), 10480-10506. https://doi.org/10.1093/mnras/stad3694

The cold dark matter (DM) model predicts that every galaxy contains thousands of DM subhaloes; almost all other DM models include a physical process that smooths away the subhaloes. The subhaloes are invisible, but could be detected via strong gravit... Read More about Scanning for dark matter subhaloes in Hubble Space Telescope imaging of 54 strong lenses.

Beyond the bulge–halo conspiracy? Density profiles of early-type galaxies from extended-source strong lensing (2023)
Journal Article
Etherington, A., Nightingale, J. W., Massey, R., Robertson, A., Cao, X., Amvrosiadis, A., Cole, S., Frenk, C. S., He, Q., Lagattuta, D. J., Lange, S., & Li, R. (2023). Beyond the bulge–halo conspiracy? Density profiles of early-type galaxies from extended-source strong lensing. Monthly Notices of the Royal Astronomical Society, 521(4), 6005-6018. https://doi.org/10.1093/mnras/stad582

Observations suggest that the dark matter and stars in early-type galaxies ‘conspire’ to produce a surprisingly simple distribution of total mass, ρ(r) ∝ ρ−γ, with γ ≈ 2. We measure the distribution of mass in 48 early-type galaxies that gravitationa... Read More about Beyond the bulge–halo conspiracy? Density profiles of early-type galaxies from extended-source strong lensing.

PyAutoGalaxy: Open-Source Multiwavelength Galaxy Structure & Morphology (2023)
Journal Article
Nightingale, J. W., Amvrosiadis, A., Hayes, R. G., He, Q., Etherington, A., Cao, X., Cole, S., Frawley, J., Frenk, C. S., Lange, S., Li, R., Massey, R. J., Negrello, M., & Robertson, A. (2023). PyAutoGalaxy: Open-Source Multiwavelength Galaxy Structure & Morphology. The Journal of Open Source Software, 8(81), Article 4475. https://doi.org/10.21105/joss.04475

Nearly a century ago, Edwin Hubble famously classified galaxies into three distinct groups: ellipticals, spirals and irregulars (Hubble, 1926). Today, by analysing millions of galaxies with advanced image processing techniques Astronomers have expand... Read More about PyAutoGalaxy: Open-Source Multiwavelength Galaxy Structure & Morphology.