Article
Astronomy & Astrophysics
A. Niemiec, M. Jauzac, D. Eckert, D. Lagattuta, K. Sharon, A. M. Koekemoer, K. Umetsu, A. Acebron, J. M. Diego, D. Harvey, E. Jullo, V Kokorev, M. Limousin, G. Mahler, P. Natarajan, M. Nonino, C. Steinhardt, S- Tam, A. Zitrin
Summary: The study presents a combined strong and weak lensing analysis of the Abell 370 cluster using the HST BUFFALO program. Seven candidate substructures were identified and evaluated for their physical significance. Five of these candidates were found to be reliable, and the mass distribution in Abell 370 was observed to extend along the north-west and south-east directions. This research provides new insights into the complex mass distribution of clusters at large cluster-centric radii.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Xiaoyue Cao, Ran Li, J. W. Nightingale, Richard Massey, Andrew Robertson, Carlos S. Frenk, Aristeidis Amvrosiadis, Nicola C. Amorisco, Qiuhan He, Amy Etherington, Shaun Cole, Kai Zhu
Summary: The distribution of mass in galaxies is more complex than the widely used elliptical power-law model. The biases caused by this model mismatch have been quantified using simulated Hubble Space Telescope imaging of lenses with mass distributions inferred from SDSS-MaNGA stellar dynamics data. Although source galaxy morphology is accurately recovered, there is a tendency to infer sources to be more compact than their true size. The recovery of the lens's Einstein radius and the global density slope is robust, but asymmetric lenses lead to a spurious fitted external shear and underestimated time delays.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
M. M. Cueli, L. Bonavera, J. Gonzalez-Nuevo, D. Crespo, J. M. Casas, A. Lapi
Summary: This paper derives observational constraints on the halo mass function by performing a tomographic analysis of the magnification bias signal on a sample of submillimeter galaxies. The results show an improvement in uncertainty reduction when tomography is adopted. The obtained results are in disagreement with the standard N-body values for the Sheth and Tormen fit.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
M. M. Cueli, L. Bonavera, J. Gonzalez-Nuevo, A. Lapi
Summary: This study aims to provide a proof-of-concept method to derive tabulated observational constraints on the halo mass function by studying the magnification bias effect. The results show that traditional fits can provide a good description of the data within certain parameter ranges.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Agniva Ghosh, Liliya L. R. Williams, Jori Liesenborgs, Ana Acebron, Mathilde Jauzac, Anton M. Koekemoer, Guillaume Mahler, Anna Niemiec, Charles Steinhardt, Andreas L. Faisst, David Lagattuta, Priyamvada Natarajan
Summary: We utilized the BUFFALO strong lensing image catalogue of Abell 370 to obtain a mass model, revealing three distinct mass features and new filament-like structure. By testing hypotheses, calculating magnification distributions, and exploring lensing effects on sources, we gained a deeper understanding of the cluster's characteristics.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Tim Schrabback, Henk Hoekstra, Ludovic Van Waerbeke, Edo van Uitert, Christos Georgiou, Marika Asgari, Patrick Cote, Jean-Charles Cuillandre, Thomas Erben, Laura Ferrarese, Stephen D. J. Gwyn, Catherine Heymans, Hendrik Hildebrandt, Arun Kannawadi, Konrad Kuijken, Alexie Leauthaud, Martin Makler, Simona Mei, Lance Miller, Anand Raichoor, Peter Schneider, Angus Wright
Summary: By combining data from five weak lensing surveys, the observational constraints on galaxy-scale halo ellipticity have been tightened, leading to a significant detection of the halo flattening signature at the mass scale of galaxies with corrected systematics.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Jacob Maresca, Simon Dye, Nan Li
Summary: This study examines a method using a Convolutional Neural Network to analyze lens modeling and source reconstruction, showcasing a significant reduction in unphysical source reconstructions by reinitializing the models based on CNN predictions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
James Pearson, Jacob Maresca, Nan Li, Simon Dye
Summary: The study trains a CNN to predict mass profile parameters of galaxy-galaxy gravitational lenses, with significantly lower errors compared to traditional methods, especially when incorporating uncertainties predicted by the CNN. Combining neural networks with conventional techniques can greatly improve accuracy and speed in automated modelling.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
C. M. O'Riordan, S. J. Warren, D. J. Mortlock
Summary: When modelling strong gravitational lenses, the widely used singular power-law model for mass profile may not be flexible enough for accurate work. A more adaptable model, the elliptical 2DBPL model, is derived to better represent the lensing properties. The study shows that the slope of the mass profile interior to the images can be accurately recovered for lenses of moderate ellipticity, contrary to the common notion.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
G. Vernardos
Summary: We present a self-consistent and versatile forward modelling software package for time-varying strongly lensed systems. It addresses the missing time dimension in existing approaches and demonstrates the importance of observation cadence and combining information from different wavelengths in correctly measuring time delays.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Andrew Robertson
Summary: The research investigates the discrepancy between observed galaxy clusters and simulated ones in producing galaxy-galaxy strong lensing (GGSL) and finds that higher resolution simulations are necessary for accurate results. Different galaxy formation models also affect the predicted GGSL probabilities in ACDM cosmology, indicating that the current understanding does not contradict the ACDM model.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Ziwen Zhang, Huiyuan Wang, Wentao Luo, H. J. Mo, Zhixiong Liang, Ran Li, Xiaohu Yang, Tinggui Wang, Hongxin Zhang, Hui Hong, Xiaoyu Wang, Enci Wang, Pengfei Li, JingJing Shi
Summary: Based on the spectroscopic and shear catalogs for SDSS galaxies in the local Universe, the study found that active galactic nuclei (AGNs) preferentially appear in the starburst and 'green valley' phases, and the stellar population of their host galaxies is independent of stellar mass, unlike typical galaxies. Additionally, AGN host galaxies share a similar SHMR with star-forming galaxies for a given stellar mass.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
G. B. Caminha, C. Grillo, P. Rosati, A. Liu, A. Acebron, P. Bergamini, K. I. Caputi, A. Mercurio, P. Tozzi, E. Vanzella, R. Demarco, B. Frye, G. Rosani, K. Sharon
Summary: This study presents a detailed strong lensing analysis of the massive and distant galaxy cluster ACT0102. The results show two mass components in the cluster, namely the cluster members and the lensing effect of a foreground group of galaxies, with very similar mass values.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Ashish Kumar Meena, Wenlei Chen, Adi Zitrin, Patrick L. Kelly, Miriam Golubchik, Rui Zhou, Amruth Alfred, Tom Broadhurst, Jose M. Diego, Alexei Filippenko, Sung Kei Li, Masamune Oguri, Nathan Smith, Liliya L. R. Williams
Summary: A transient event was discovered in a strongly lensed arc in the Abell 370 galaxy cluster, observed through the Hubble Space Telescope. The transient is detected at a specific magnitude in two different observed epochs, and is identified as a lensed star candidate based on its location and brightness. The observation also reveals a time delay and a blue color, ruling out other transient candidates. This discovery suggests that more similar events can be expected in future cluster surveys with the Hubble Space Telescope and JWST.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
A. Acebron, C. Grillo, P. Bergamini, G. B. Caminha, P. Tozzi, A. Mercurio, P. Rosati, G. Brammer, M. Meneghetti, M. Nonino, E. Vanzella
Summary: SDSS J2222+2745 is a promising lens cluster for cosmological studies, but additional information is needed for accurate measurements due to its complex morphology and model degeneracies.
ASTRONOMY & ASTROPHYSICS
(2022)