Article
Astronomy & Astrophysics
Fabrizio Gentile, Crescenzo Tortora, Giovanni Covone, Leon V. E. Koopmans, Chiara Spiniello, Zuhui Fan, Rui Li, Dezi Liu, Nicola R. Napolitano, Mattia Vaccari, Liping Fu
Summary: The authors identified 16 likely strong gravitational lenses using CNNs on data from the VOICE survey, with two different CNNs trained on composite images to accurately identify systems with different Einstein radii. The high-confidence lens candidate sample was visually inspected by nine of the authors, with roughly 75% of the systems classified as likely lenses. This work confirms the effectiveness of CNNs in inspecting large samples of galaxies for gravitational lenses, which will be crucial for future surveys with the Euclid satellite and the Vera Rubin Observatory.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
H. Wang, R. Canameras, G. B. Caminha, S. H. Suyu, A. Yildirim, G. Chirivi, L. Christensen, C. Grillo, S. Schuldt
Summary: We study the inner structure of the group-scale lens CASSOWARY 31 by adopting both strong lensing and dynamical modeling. Our results show that CSWA 31 is a peculiar fossil group, strongly dark-matter dominated toward the central region, and with a projected total mass profile similar to higher-mass cluster-scale halos.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Amy Etherington, James W. Nightingale, Richard Massey, Andrew Robertson, XiaoYue Cao, Aristeidis Amvrosiadis, Shaun Cole, Carlos S. Frenk, Qiuhan He, David J. Lagattuta, Samuel Lange, Ran Li
Summary: Observations suggest that the combination of dark matter and stars in early-type galaxies leads to a surprisingly simple mass distribution. By analyzing 48 early-type galaxies with gravitational lensing effects, we find a consistent mass distribution with a mean value of 2.075 and an intrinsic scatter of 0.172. However, when measuring the dependence of surface mass density on lens galaxy, the consistency breaks down, indicating the presence of an inflection point in the total mass-density profile.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Anowar J. Shajib, Tommaso Treu, Simon Birrer, Alessandro Sonnenfeld
Summary: By utilizing a joint lensing-dynamics analysis, the study investigates the internal structure of elliptical galaxies at a redshift of z≈0.2, revealing that dark matter haloes are well described by a standard Navarro-Frenk-White halo. Additionally, comparison of inferred stellar masses with those obtained from the stellar population synthesis method supports a heavy initial mass function (IMF) such as the Salpeter IMF.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Abdolhosein Hashemizadeh, Simon P. Driver, Luke J. M. Davies, Aaron S. G. Robotham, Sabine Bellstedt, Rogier A. Windhorst, Malcolm Bremer, Steven Phillipps, Matt Jarvis, Benne W. Holwerda, Claudia del P. Lagos, Soheil Koushan, Malgorzata Siudek, Natasha Maddox, Jessica E. Thorne, Pascal Elahi
Summary: By visually classifying galaxies at redshifts less than 1, it was found that optical morphological classification becomes increasingly difficult as redshift increases. Around two-thirds of the total stellar mass of the Universe was already in place by a redshift of about 1, with double-component galaxies dominating the stellar mass density at all epochs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
J. Dabringhausen, P. Kroupa
Summary: This article discusses the radial accelerations of 462 early-type galaxies (ETGs) at their half-mass radii. By comparing them with the baryonic masses of the same galaxies, it is found that the Newtonian radial acceleration relation (RAR) fails at low masses without non-baryonic dark matter, but the two MONDian RARs may still work. However, all RARs fail at high masses unless the theory of integrated galaxy-wide stellar initial mass functions (IGIMFs) is used.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Anowar J. Shajib, Eden Molina, Adriano Agnello, Peter R. Williams, Simon Birrer, Tommaso Treu, Christopher D. Fassnacht, Takahiro Morishita, Louis Abramson, Paul L. Schechter, Lutz Wisotzki
Summary: The study reports on 3 years of follow-up and confirmation work using the Near-Infrared Camera, identifying a total of 15 lenses and forming a sample of 20 lenses. The research also provides lens properties and predicted time delays to aid in planning follow-up observations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Adriano Poci, Russell J. Smith
Summary: In this study, we compare the mass estimates derived from independent modelling techniques based on the relative proximity of the nearby strong-lens galaxy SNL-1. Our results show that SNL-1 has a constant intermediate triaxiality at all radii, and occupies the most-compact edge on the mass-size plane. We also investigate how the observed lensing configuration is affected by the orientation of the lens galaxy.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Alessandro Sonnenfeld, Crescenzo Tortora, Henk Hoekstra, Marika Asgari, Maciej Bilicki, Catherine Heymans, Hendrik Hildebrandt, Konrad Kuijken, Nicola R. Napolitano, Nivya Roy, Edwin Valentijn, Angus H. Wright
Summary: Using weak gravitational lensing observations, this study investigates the relationship between the dark matter halo mass and the properties of massive elliptical galaxies. The results show that there is no significant correlation between the halo mass and the half-light radius or colour of the galaxies, indicating that the average star formation efficiency of these galaxies is not dependent on their final size or colour. This suggests that the diversity in the size and colour distribution of massive elliptical galaxies may be attributed to other factors.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
R. Gobat, C. D'Eugenio, D. Liu, G. B. Caminha, E. Daddi, D. Blanquez
Summary: The amount of gas and dust in high-redshift quiescent galaxies is still uncertain, with few and contradictory answers. New research suggests that the dust content is more complex than previously thought, and the measurement results are highly sensitive to the adopted extraction method and conversion factors.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
E. Perez-Hernandez, S. N. Kemp, V. H. Ramirez-Siordia, A. Nigoche-Netro
Summary: This study presents a comprehensive investigation of deep optical long-slit spectroscopy and deep broad-band photometry of NGC 6086. The results reveal the presence of two separate structures in NGC 6086 and the existence of an envelope. Additionally, the study finds radial discontinuity in the distribution of galaxies in the cluster A2162, indicating the need for further investigation of the cluster's kinematics.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Roohi Dalal, Michael A. Strauss, Tomomi Sunayama, Masamune Oguri, Yen-Ting Lin, Song Huang, Youngsoo Park, Masahiro Takada
Summary: This study focuses on brightest cluster galaxies (BCGs) in approximately 5000 galaxy clusters from the HSC Subaru Strategic Program, indicating that BCGs are 'special' and not consistent with the mass distribution of other cluster galaxies, especially at high redshifts.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Shawn Knabel, B. W. Holwerda, J. Nightingale, T. Treu, M. Bilicki, S. Brough, S. Driver, L. Finnerty, L. Haberzettl, S. Hegde, A. M. Hopkins, K. Kuijken, J. Liske, A. K. Pimblett, R. C. Steele, A. H. Wright
Summary: This study applies automated Bayesian lens modelling methods to large-survey data from KiDS and GAMA in order to model strong gravitational lenses. The results demonstrate the feasibility of modelling strong lenses with lower resolution large-survey data as a complementary approach to studying individual lenses at higher resolution.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
M. Bernardi, H. Dominguez Sanchez, R. K. Sheth, J. R. Brownstein, R. R. Lane
Summary: We investigated the systematic errors associated with estimating SSP parameters and M*/L gradients of different types of galaxies using stacked spectra from the MaNGA survey. The method of spectrum normalization, emission subtraction, spectrum fitting strategy, and choice of SSP models all contribute to these systematics. We found that the central regions of elliptical slow rotators show younger ages and lower alpha enhancement values, while central regions have higher [M/H] values. The IMF is also found to be more bottom-heavy in the central regions. There are differences among E-SRs, E-FRs, and S0s in terms of their ages and alpha enhancement values, suggesting that they are not SSPs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
M. Bernardi, H. Dominguez Sanchez, R. K. Sheth, J. R. Brownstein, R. R. Lane
Summary: This study examines the systematics in estimating simple stellar population (SSP) parameters and associated M-*/L gradients of different types of galaxies. The methods used for stacking spectra, subtracting emission, choosing the fitting range, and different SSP models all contribute to the uncertainties in the estimates. The results show clear differences between elliptical slow rotators (E-SRs), fast rotators (E-FRs), and S0s, suggesting that they are not SSPs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Russell J. Smith, John R. Lucey, Alastair C. Edge
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2017)
Article
Astronomy & Astrophysics
William P. Collier, Russell J. Smith, John R. Lucey
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
M. Mezcua, J. Hlavacek-Larrondo, J. R. Lucey, M. T. Hogan, A. C. Edge, B. R. McNamara
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
William P. Collier, Russell J. Smith, John R. Lucey
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
John R. Lucey, Paul L. Schechter, Russell J. Smith, T. Anguita
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
P. D. Alton, R. J. Smith, J. R. Lucey
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
Russell J. Smith, John R. Lucey, William P. Collier
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
Article
Astronomy & Astrophysics
William P. Collier, Russell J. Smith, John R. Lucey
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
Khaled Said, Matthew Colless, Christina Magoulas, John R. Lucey, Michael J. Hudson
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
Omar Ruiz-Macias, Pauline Zarrouk, Shaun Cole, Carlton M. Baugh, Peder Norberg, John Lucey, Arjun Dey, Daniel J. Eisenstein, Peter Doel, Enrique Gaztanaga, ChangHoon Hahn, Robert Kehoe, Ellie Kitanidis, Martin Landriau, Dustin Lang, John Moustakas, Adam D. Myers, Francisco Prada, Michael Schubnell, David H. Weinberg, M. J. Wilson
Summary: In this study, a reliable and complete input galaxy catalogue for the DESI BGS was produced using Legacy Survey DR8 DECam, addressing key issues in target selection and validating completeness and performance by cross-matching with the GAMA survey. Additionally, clustering of sources in the BGS catalogue was validated and the dependence of target galaxy density on imaging and other properties was assessed to evaluate the robustness of the selection criteria.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Madhooshi R. Senarath, Michael J. Brown, Michelle E. Cluver, Thomas H. Jarrett, Christian Wolf, Nicholas P. Ross, John R. Lucey, Vaishali Parkash, Wei J. Hon
Summary: The research team conducted a systematic survey for AGNs with redshift z < 0.04 that may have changed spectral class over the past decade. Through optical color selection method, they identified four AGNs with varying spectra and confirmed two new CLAGNs, NGC 1346 and 2MASX J20075129-1108346.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Joseph B. Jensen, John P. Blakeslee, Chung-Pei Ma, Peter A. Milne, Peter J. Brown, Michele Cantiello, Peter M. Garnavich, Jenny E. Greene, John R. Lucey, Anh Phan, R. Brent Tully, Charlotte M. Wood
Summary: High-quality surface brightness fluctuation (SBF) distances were measured for 63 massive early-type galaxies using the Hubble Space Telescope. Significant improvements to the SBF calibration and data analysis procedures were required for achieving precision at distances of 50-100 Mpc. The study demonstrates the versatility of the SBF method for measuring distances to galaxies with evolved stellar populations and constraining the local value of the Hubble constant up to 100 Mpc.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2021)
Article
Astronomy & Astrophysics
Stuart McAlpine, John C. Helly, Matthieu Schaller, Till Sawala, Guilhem Lavaux, Jens Jasche, Carlos S. Frenk, Adrian Jenkins, John R. Lucey, Peter H. Johansson
Summary: sibelius-dark is a constrained realization simulation of the local volume, which accurately matches observational data and provides important insights into the large-scale structure and galaxy populations of the universe.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Cullan Howlett, Khaled Said, John R. Lucey, Matthew Colless, Fei Qin, Yan Lai, R. Brent Tully, Tamara M. Davis
Summary: This study presents a catalogue of distances and velocities of early-type galaxies derived from the Sloan Digital Sky Survey. The catalogue provides a large and accurate dataset for studying the properties and structure of galaxies and the universe.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Russell J. Smith, William P. Collier, Shinobu Ozaki, John R. Lucey
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)