Article
Astronomy & Astrophysics
Guy Worthey, Xiang Shi, Tathagata Pal, Hyun-chul Lee, Baitian Tang
Summary: Stellar evolution calculations with variable abundance ratios were used to investigate the effects on temperatures, luminosities, and lifetimes in different phases. The temperature variable was found to have the most significant impact on integrated light models, rather than the time-scale or luminosity. By deriving a method to include abundance-sensitive temperature effects, enhanced isochrones were generated and incorporated into stellar population models for comparison with galaxy data. The study revealed a strong oxygen-age degeneracy and an increase in the age range of early-type galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Taniya Parikh, Daniel Thomas, Claudia Maraston, Kyle B. Westfall, Brett H. Andrews, Nicholas Fraser Boardman, Niv Drory, Grecco Oyarzun
Summary: By studying a large sample of galaxies, differences in age, metallicity, and various element abundances between ETGs and LTGs were identified. The age gradients in LTGs were found to be negatively correlated with galaxy mass, while internal processes regulated metallicity in ETGs rather than age. Different galaxy types exhibit distinct gradient characteristics.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
P. Rodriguez-Beltran, A. Vazdekis, M. Cervino, M. A. Beasley
Summary: The study explores the potential of utilizing surface brightness fluctuations (SBF) for studying composite stellar populations (CSP) by calculating models composed of different mass fractions of two single stellar populations. The findings show that combining mean and SBF values simultaneously leads to improved results in revealing small secondary components in elliptical galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
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
Yu-Zhong Wu, Wei Zhang
Summary: This study analyzes 4615 star-forming early-type galaxies (ETGs) using data from the Galaxy Zoo and Max Planck Institute for Astrophysics-Johns Hopkins University (MPA-JHU) emission-line measurements. It reveals a significant trend of lower/higher stellar mass ETGs having lower/higher star formation rates (SFRs), and establishes a best-fit model for the SFR and stellar mass relationship. The study also highlights the correlation of stellar mass-metallicity (MZ) relation in star-forming ETGs, as well as potential sources for higher metallicity measurements.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Francesco D'Eugenio, Matthew Colless, Nicholas Scott, Arjen van der Wel, Roger L. Davies, Jesse van de Sande, Sarah M. Sweet, Sree Oh, Brent Groves, Rob Sharp, Matt S. Owers, Joss Bland-Hawthorn, Scott M. Croom, Sarah Brough, Julia J. Bryant, Michael Goodwin, Jon S. Lawrence, Nuria P. F. Lorente, Samuel N. Richards
Summary: The study focuses on the Fundamental Plane (FP) of early-type galaxies using data from the SAMI survey. It finds that the FP residuals are most strongly correlated with luminosity-weighted simple stellar population (SSP) age, rather than with structural observables. The scatter in the FP is partly attributed to the broad age and Upsilon(*) distribution at any given surface mass density.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Hyunjin Jeong, Kyuseok Oh, Seok-Joo Joo, Sukyoung K. Yi
Summary: Based on GALEX UV data and SUSS data, a study characterized the stellar population properties of luminous early-type galaxies, finding that 7.7% of the sample galaxies exhibit recent star formation and tend to be more metal-poor, possibly due to external processes such as mergers or interactions driving the observed star formation activity.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
A. E. Watkins, H. Salo, E. Laurikainen, S. Diaz-Garcia, S. Comeron, J. Janz, A. H. Su, R. Buta, E. Athanassoula, A. Bosma, L. C. Ho, B. W. Holwerda, T. Kim, J. H. Knapen, S. Laine, K. Menendez-Delmestre, R. F. Peletier, K. Sheth, D. Zaritsky
Summary: The Spitzer Survey of Stellar Structure in Galaxies (S(4)G) is a detailed study of over 2300 nearby galaxies in the near-infrared, which has been critical to our understanding of the detailed structures of nearby galaxies. A follow-up Spitzer survey was conducted to add early-type galaxies (ETGs) to the sample and analyze them in a consistent manner. The results show various scaling relations among the derived parameters and highlight differences between ETGs and late-type galaxies (LTGs).
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
I. Martin-Navarro, F. Pinna, L. Coccato, J. Falcon-Barroso, G. van de Ven, M. Lyubenova, E. M. Corsini, K. Fahrion, D. A. Gadotti, E. Iodice, R. M. McDermid, A. Poci, M. Sarzi, T. W. Spriggs, S. Viaene, P. T. de Zeeuw, L. Zhu
Summary: The stellar initial mass function (IMF) is crucial in interpreting astronomical observables and understanding baryonic processes within galaxies. The universality of the IMF, suggested by observations in our Milky Way, has been questioned due to excess low-mass stars in massive quiescent galaxies. Studying 23 quiescent galaxies in the Fornax cluster revealed that IMF maps exhibit various behaviors linked to metallicity, but metallicity alone cannot fully explain their complexity.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
M. L. L. Dantas, P. R. T. Coelho, P. Sanchez-Blazquez
Summary: The study compares UV weak and upturn galaxies in terms of their stellar population properties, using propensity score matching to mitigate biases. Results show that UV upturn galaxies are redder in the optical, more metallic, and had earlier last burst of star-formation, suggesting they have shorter star-formation histories and evolved more passively compared to UV weak galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Soumavo Ghosh, Kanak Saha, Paola Di Matteo, Francoise Combes
Summary: The study investigates the dynamical impact of a minor galaxy merger on the fate of a stellar bar in the merger remnant, finding that the central stellar bar weakens substantially in the post-merger remnants. The efficiency of mass accumulation from the satellite in the central parts of merger remnants depends on the orbital parameters as well as on the satellite's morphology. Consequently, different minor merger models display different degrees of bar-weakening event, suggesting that minor galaxy mergers are a plausible avenue for bar weakening in disc galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
P. Lagos, S. Loubser, T. C. Scott, E. O'Sullivan, K. Kolokythas, A. Babul, A. Nigoche-Netro, V Olivares, C. Sengupta
Summary: By investigating the ionized gas in early-type group-dominant galaxies, we found that the ionization sources have different impacts at different radii, with low-luminosity active galactic nuclei influencing the central regions and other mechanisms ionizing the extended low-ionization nuclear emission-line region-like emission. We also discovered that the gas-phase metallicity decreases with radius, and the extended structures have shallow metallicity gradients.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Guy Worthey, Xiang Shi
Summary: Integrated light models incorporating chemically peculiar stars improve accuracy of recovered stellar population parameters, but do not show unique age information from CP star features compared to other methods. Some local group galaxies have older stellar populations, while NGC 205 stands out for its younger component.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Davide Bevacqua, Michele Cappellari, Silvia Pellegrini
Summary: We present the integral-field kinematics and stellar population properties of 64 galaxies with Counter-Rotating stellar Disks (CRD) selected from the MaNGA survey. The study reveals that CRDs have similar trends in age and metallicity to Early-Type galaxies (ETGs), but are less metallic at low masses, and show flatter age and steeper metallicity gradients, on average. The results suggest that CRDs mainly form via gas accretion in retrograde rotation with respect to a pre-existing stellar disc.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
C. Pulsoni, O. Gerhard, M. Arnaboldi, A. Pillepich, V. Rodriguez-Gomez, D. Nelson, L. Hernquist, V. Springel
Summary: The study reveals that the rotational support and intrinsic shapes of stellar halos in early-type galaxies are influenced by their accretion and merger histories, as well as the stellar mass. Low-mass galaxies are mainly driven by in-situ stars in shaping their halos, while high-mass galaxies and events with high f(exsitu) values affect the rotation velocity and shape.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Ryan Leaman, Glenn van de Ven
Summary: A simple model is presented to study the relationship between galaxy nucleation fraction, nuclear star cluster mass, and surviving globular cluster mass in galaxies. The analytical expression for the critical mass limit above which a globular cluster can in-spiral to the galaxy center and survive tidal dissolution is found to be crucial in modeling the nucleation fraction for populations of galaxies. The model predicts limits to the relationships between galaxy mass and globular cluster mass as well as nuclear star cluster mass, while also illustrating how these scaling relations vary with changes in star cluster formation efficiency, galaxy environment, and galaxy size-mass relation.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
David Sobral, Arjen van der Wel, Rachel Bezanson, Eric Bell, Adam Muzzin, Francesco D'Eugenio, Behnam Darvish, Anna Gallazzi, Po-Feng Wu, Michael Maseda, Jorryt Matthee, Ana Paulino-Afonso, Caroline Straatman, Pieter G. van Dokkum
Summary: Galaxy evolution is influenced by various physical processes, and their rates differ for different dark matter haloes and environments. By using absorption-line spectroscopy, this study examines the impact of environment and stellar mass on galaxy stellar populations in the COSMOS field at around z~0.6-1. The findings indicate that the characteristics of stellar populations, such as D(n)4000 and H delta equivalent widths, not only depend on stellar mass but also on the environment.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Pablo M. Galan-de Anta, M. Sarzi, A. Pillepich, Y. Ding, L. Zhu, L. Coccato, E. M. Corsini, K. Fahrion, J. Falcon-Barroso, D. A. Gadotti, E. Iodice, M. Lyubenova, I Martin-Navarro, R. M. McDermid, F. Pinna, G. van de Ven, P. T. de Zeeuw
Summary: In this study, the evolution of kinematically defined stellar discs in Fornax-like clusters from the IllustrisTNG simulations was investigated. It was found that very few stellar discs survive in such dense environments, which is consistent with the survival rates observed in other massive clusters. However, the low number of present-day disc galaxies in Fornax-like clusters contradicts the presence of edge-on disc galaxies observed in the actual Fornax cluster. Additionally, the comparison of stellar population properties revealed that some disc galaxies in Fornax have unique features that cannot be matched by any disc galaxies in the simulations. These findings suggest the need for future studies on passive cluster spirals to further understand cosmological simulations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Camila de Sa-Freitas, Francesca Fragkoudi, Dimitri A. Gadotti, Jesus Falcon-Barroso, Adrian Bittner, Patricia Sanchez-Blazquez, Glenn van de Ven, Rebekka Bieri, Lodovico Coccato, Paula Coelho, Katja Fahrion, Geraldo Goncalves, Taehyun Kim, Adriana de Lorenzo-Caceres, Marie Martig, Ignacio Martin-Navarro, Jairo Mendez-Abreu, Justus Neumann, Miguel Querejeta
Summary: Determining the age of galactic bars is crucial for understanding galaxy formation and evolution. This study presents a new methodology for obtaining the age of bars by examining the star formation history of nuclear discs. The method is applied to the galaxy NGC 1433, revealing the presence of a 7.5 billion-year-old bar and providing evidence for inside-out growth of the nuclear disc.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Y. Ding, L. Zhu, G. van de Ven, L. Coccato, E. M. Corsini, L. Costantin, K. Fahrion, J. Falcon-Barroso, D. A. Gadotti, E. Iodice, M. Lyubenova, I. Martin-Navarro, R. M. McDermid, F. Pinna, M. Sarzi
Summary: In this study, we used the MUSE/VLT observations from the Fornax3D project to analyze 16 galaxies in the Fornax cluster. By fitting various properties of the galaxies simultaneously, we obtained information about the internal stellar orbit distribution and the age and metallicity distribution on different orbits. Our findings reveal a strong correlation between the age of the cold disk in galaxies and their infall time into the cluster. Furthermore, we found that the assembly of cold disks in galaxies is influenced by their infall into clusters, leading to differences in the age gradient between the inner and outer disks.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Natascha Sattler, Francesca Pinna, Nadine Neumayer, Jesus Falcon-Barroso, Marie Martig, Dimitri A. Gadotti, Glenn van de Ven, Ivan Minchev
Summary: We trace the evolution of the edge-on spiral galaxy NGC 3501 using deep integral-field spectroscopy MUSE observations. The study presents stellar kinematic and population maps, as well as the star formation history, of the galaxy. The maps reveal a young galaxy with a thicker metal-poor structure and an inner metal-rich one. Comparison of the star formation history suggests the formation of a future massive thin disc embedded in the preexisting thicker disc.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Computer Science, Artificial Intelligence
Fabian Hinterer, Simon Hubmer, Prashin Jethwa, Kirk M. Soodhalter, Glenn van de Ven, Ronny Ramlau
Summary: In this paper, the problem of reconstructing a galaxy's stellar population-kinematic distribution function from optical integral field unit measurements is investigated. A projected Nesterov-Kaczmarz reconstruction method is proposed to efficiently solve the high-dimensional integral equation and incorporate physical prior information. The performance of the reconstruction approach is tested using a simulated dataset and compared to the widely used pPXF software.
SIAM JOURNAL ON IMAGING SCIENCES
(2023)
Article
Astronomy & Astrophysics
E. J. Lilley, G. van de Ven
Summary: We propose a unified approach to describing (bi-)orthogonal basis sets for gravitating systems. The concept of mutual gravitational energy is central to our discussion, leading to a 'self-energy inner product' on mass densities. We examine a self-adjoint first-order differential operator with respect to this inner product and prove a general theorem that specifies the conditions for a (bi-)orthogonal basis set to arise through repeated application of this operator. We demonstrate the fulfillment of these conditions by existing families of analytical basis sets with infinite extent. Moreover, our new theoretical framework is closely connected to Fourier-Mellin transforms and serves as a powerful tool for constructing general basis sets. To illustrate this, we derive a basis set for the isochrone model and validate its numerical reliability by reproducing a known result on unstable radial modes.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Fabian Parzer, Prashin Jethwa, Alina Boecker, Mayte Alfaro-Cuello, Otmar Scherzer, Glenn van de Ven
Summary: This article introduces a method for uncertainty-aware blob detection in stellar population modelling. The method utilizes the classic Laplacian-of-Gaussians method and introduces an efficient method for computing uncertainties in spectral modelling. The method was applied to data from the star cluster M 54, identifying 2-3 significant and distinct populations among its stars.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Mohammad Akhshik, Katherine E. Whitaker, Joel Leja, Johan Richard, Justin S. Spilker, Mimi Song, Gabriel Brammer, Rachel Bezanson, Harald Ebeling, Anna R. Gallazzi, Guillaume Mahler, Lamiya A. Mowla, Erica J. Nelson, Camilla Pacifici, Keren Sharon, Sune Toft, Christina C. Williams, Lillian Wright, Johannes Zabl
Summary: REQUIEM-2D is a survey that combines natural magnification from strong gravitational lensing with high-spatial-resolution grism spectroscopy of the Hubble Space Telescope to study spatially resolved stellar populations in eight massive quiescent galaxies at z similar to 2. The survey reveals diverse formation histories with age gradients at the 1 sigma- 3 sigma level, challenging the currently accepted paradigm of how massive quiescent galaxies form. The results also suggest that earlier-formed galaxies exhibit slow and uniform growth in their inner core, while later-formed galaxies have rapid inner growth with younger ages than the outskirts.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Giulia Santucci, Sarah Brough, Jesse van de Sande, Richard McDermid, Stefania Barsanti, Joss Bland-Hawthorn, Julia J. Bryant, Scott M. Croom, Claudia Lagos, Jon S. Lawrence, Matt S. Owers, Glenn van de Ven, Sam P. Vaughan, Sukyoung K. Yi
Summary: Most dynamical models of galaxies assume axisymmetry but this is not the case for a significant fraction of massive galaxies. Using Schwarzschild models, we reconstructed the inner orbital structure and mass distribution of 153 passive galaxies observed by the SAMI Galaxy Survey. We found that environment plays a role in shaping the internal structures and properties of these galaxies, with denser regions exhibiting more radial anisotropy.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
A. Zanella, F. Valentino, A. Gallazzi, S. Belli, G. Magdis, A. Bolamperti
Summary: Post-starburst galaxies at redshift z > 1 are important for studying the cessation of star formation. Our CO(3-2) ALMA observations of two massive post-starburst galaxies indicate a molecular gas fraction of f(H2) = M-H2/M-⋆ & SIM; 8-16%, consistent with z < 1 post-starburst galaxies. The decrease in gas content after the last major burst of star formation is correlated with the D(n)4000 spectral index, suggesting a gradual decline. Additionally, one of our targets is undergoing a major merger phase with star-forming companions, indicating that perturber events may quench star formation without removing all the molecular gas.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Tutku Kolcu, Witold Maciejewski, Dimitri A. Gadotti, Francesca Fragkoudi, Peter Erwin, Patricia Sanchez-Blazquez, Justus Neumann, Glenn Van de Ven, Camila de Sa-Freitas, Steven Longmore, Victor P. Debattista
Summary: In this study, we use VLT/MUSE integral-field spectroscopic data to search for extended coherent shocks that drive gas inflows in the centres of galaxies, focusing on the barred spiral galaxy NGC 1097. We explore different techniques to identify these shocks, considering the potential distortions caused by inaccurate velocity extraction and other factors like rotational flow and stellar outflows. By including multiple components in the emission-line fits and examining differences in the LOSVD moments, we are able to reveal the presence of continuous shocks in the inward regions of NGC 1097, supporting the nuclear spiral models.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Po-Feng Wu, Rachel Bezanson, Francesco D'Eugenio, Anna R. Gallazzi, Jenny E. Greene, Michael V. Maseda, Katherine A. Suess, Arjen van der Wel
Summary: We present a multiwavelength study of five post-starburst galaxies at z similar to 0.7, examining their stars, gas, and star formation activities. We observe a high incidence of companion galaxies and tidal features, indicating a close relationship between galaxy interactions and quenching. We model the stellar continuum and detect molecular gas spreading over a large distance. Based on comparisons between different parameters, we find a low star-forming efficiency.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Bahar Bidaran, Francesco La Barbera, Anna Pasquali, Glenn van de Ven, Reynier Peletier, Jesus Falcon-Barroso, Dimitri A. Gadotti, Agnieszka Sybilska, Eva K. Grebel
Summary: Using MUSE data, this study investigates the radial gradients of stellar population properties and finds that dwarf early-type galaxies experienced intense star formation before their infall onto the Virgo cluster. Additionally, younger, more metal-rich, and less alpha-enhanced stellar populations dominate their inner regions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)