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
F. La Barbera, A. Vazdekis, I Ferreras, A. Pasquali
Summary: The study investigated the radial gradients of optical and near-infrared initial mass function (IMF)-sensitive features along the major axis of the central bulge of M31, finding varying IMF distributions at different galactocentric distances.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
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
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
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
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
L. Cortese, A. Fraser-McKelvie, J. Woo, B. Catinella, K. E. Harborne, J. van de Sande, J. Bland-Hawthorn, S. Brough, J. J. Bryant, S. Croom, S. Sweet
Summary: In this study, the correlation between stellar surface density (sigma(1)) and the proxy for stellar spin parameter (lambda(re)) was investigated for 1599 nearby galaxies. The results showed that changes in sigma(1) were mirrored by changes in lambda(re) on the star-forming main sequence, but not below it. Passive galaxies were found to be more heterogeneous in terms of their structure compared to star-forming galaxies and may have followed different evolutionary paths.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(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
Alister W. Graham
Summary: One of the longstanding problems in astronomy is understanding the evolution of galaxy morphology. Recent research has found that spiral galaxies serve as a bridging population between low-mass accretion-built galaxies and dusty merger-built lenticular galaxies. Additionally, a new morphology sequence called the "Triangal" has been identified, which highlights the bridging nature of overlooked lenticular galaxies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
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
Alister W. Graham, Nandini Sahu
Summary: We present revised scaling relations between black hole mass and spheroid stellar mass, as well as galaxy stellar mass, based on color-dependent stellar mass-to-light ratios. By decomposing luminosities obtained at 3.6 micrometers, we consider various components and show how disc-galaxy mergers explain the offset between lenticular galaxy bulges and elliptical galaxies. We confirm a steep scaling relation for spiral galaxies and discuss the implications of this work, including the role of mergers in shaping the high-mass end of the galaxy mass function.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Massimiliano Matteuzzi, Federico Marinacci, Carlo Nipoti, Stefano Andreon
Summary: Based on cosmological simulations, this research explores the size evolution of massive satellite early-type galaxies (ETGs) in galaxy clusters. It is found that the effective radius of these galaxies tends to be larger at lower redshifts. The simulation reveals that the acquisition of new galaxies and the transformation of existing galaxies contribute to this size evolution. The stellar mass function of these simulated satellite ETGs does not significantly differ between different redshifts.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Evelyn J. Johnston, Boris Haussler, Keerthana Jegatheesan, Amelia Fraser-McKelvie, Lodovico Coccato, Arianna Cortesi, Yara Jaffe, Gaspar Galaz, Marcelo Mora, Yasna Ordenes-Briceno
Summary: This study used BUDDI to extract the spectra of the bulges and discs of 78 S0 galaxies and compared their stellar populations. The results show that bulges are generally older and more metal rich than discs. The stellar mass of a galaxy plays a more significant role in the formation of bulges. More massive S0 galaxies form through an inside-out scenario, while lower mass ones may form through an outside-in scenario or together with the discs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Junqiang Ge, Shude Mao, Youjun Lu, Michele Cappellari, Richard J. Long, Renbin Yan
Summary: The study reveals that the gradient of stellar mass-to-light ratio varies with galaxy mass and is heavily influenced by stellar age. Galaxies with higher specific star formation rates show steeper negative del(M-*/L-r) gradients.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
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
Automation & Control Systems
Marco Augusto Vasquez-Beltran, Bayu Jayawardhana, Reynier F. Peletier
Summary: In this work, we studied a class of Duhem hysteresis operators that can exhibit butterfly loops. We first investigated the consistency property of such operators, which corresponds to the existence of an attractive periodic solution under a periodic input signal. We then studied the two defining functions of the Duhem operator to allow corresponding periodic solutions to have a butterfly input-output phase plot. Several examples were presented where Duhem butterfly hysteresis operators were constructed using two zero-level set curves that satisfy certain mild conditions.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(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
Eirini Angeloudi, Jesus Falcon-Barroso, Marc Huertas-Company, Regina Sarmiento, Annalisa Pillepich, Daniel Walo-Martin, Lukas Eisert
Summary: Quantifying the contribution of mergers to the stellar mass of galaxies is crucial for understanding galaxy formation. This study uses machine learning to investigate the accuracy of inferring the fraction of accreted stars in nearby galaxies based on observable properties and different galaxy formation models. The results show high accuracy at fixed simulation, but a lack of generalization to different models. However, using only stellar mass and kinematics maps for training can remove the bias and recover the ex situ stellar mass fraction with low scatter in both simulations. This suggests the potential for robust inference of galaxy accretion histories from existing surveys.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Alessandro Loni, Paolo Serra, Marc Sarzi, Gyula I. G. Jozsa, Pablo M. Galan-de Anta, Nikki Zabel, Dane Kleiner, Filippo M. Maccagni, Daniel Molnar, Mpati Ramatsoku, Francesca Loi, Enrico M. Corsini, D. J. Pisano, Peter Kamphuis, Timothy A. Davis, W. J. G. de Blok, Ralf J. Dettmar, Jesus Falcon-Barroso, Enrichetta Iodice, Maritza A. Lara-Lopez, S. Ilani Loubser, Kana Morokuma-Matsui, Reynier Peletier, Francesca Pinna, Adriano Poci, Matthew W. L. Smith, Scott C. Trager, Glenn van de Ven
Summary: We study the evolutionary path of NGC 1436 in the Fornax Cluster and find that it is transitioning from a spiral to a lenticular morphology. The star-forming disc is confined within the inner region, while the cold gas disc has settled and has not been affected by environmental interactions in the last 1 billion years. The star-formation history shows a burst of star formation 5 billion years ago followed by quenching in the outer disc and continued star formation in the inner disc.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Kai Zhu, Shengdong Lu, Michele Cappellari, Ran Li, Shude Mao, Liang Gao
Summary: This paper presents a catalogue of dynamically determined quantities for over 10,000 nearby galaxies using the MaNGA survey. The dynamical properties are extracted using the JAM method and systematic uncertainties are assessed using eight dynamical models. The catalogue provides quantities related to mass distributions and complete models for each galaxy.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Kai Zhu, Ran Li, Xiaoyue Cao, Shengdong Lu, Michele Cappellari, Shude Mao
Summary: This paper derived an empirical aperture correction formula and provided a lookup table of correction factors for different galaxy types. They also provided a Python script to obtain the correction factors from the lookup table.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Christian R. Hayes, Kim A. Venn, Fletcher Waller, Jaclyn Jensen, Alan W. Mcconnachie, John Pazder, Federico Sestito, Andre Anthony, Gabriella Baker, John Bassett, Joao Bento, Trystyn Berg, Gregory Burley, Jurek Brzeski, Scott Case, Edward Chapin, Timothy Chin, Eric Chisholm, Vladimir Churilov, Adam Densmore, Ruben Diaz, Jennifer Dunn, Michael Edgar, Tony Farrell, Veronica Firpo, Joeleff Fitzsimmons, Juan Font-Serra, Javier Fuentes, Colin Ganton, Manuel Gomez-Jimenez, Tim Hardy, David Henderson, Alexis Hill, Brian Hoff, Michael Ireland, Venu Kalari, Neal Kelly, Urs Klauser, Yuriy Kondrat, Kathleen Labrie, Sam Lambert, Lance Luvaul, Jon Lawrence, Jordan Lothrop, G. Scott Macdonald, Slavko Mali, Steve Margheim, Richard Mcdermid, Helen Mcgregor, Bryan Miller, Felipe Miranda, Rolf Muller, Jon Nielsen, Ryan Norbury, Oliver Oberdorf, Naveen Pai, Gabriel Perez, Pablo Prado, Ian Price, Carlos Quiroz, Vladimir Reshetov, Gordon Robertson, Roque Ruiz-Carmona, Ricardo Salinas, Kim M. Sebo, Andrew Sheinis, Matthew Shetrone, Keith Shortridge, Katherine Silversides, Karleyne Silva, Chris Simpson, Greg Smith, Kei Szeto, Julia Tims, Eduardo Toro, Cristian Urrutia, Sudharshan Venkatesan, Lewis Waller, Ivan Wevers, Ramunas Wierzbicki, Marc White, Peter Young, Ross Zhelem
Summary: This paper presents the first science results from the GHOST spectrograph and its observations of a benchmark star and stars in the Reticulum II dwarf galaxy. The candidate member GDR3 0928 is confirmed to be a member of Ret ii and exhibits abundance patterns similar to CEMP-no stars in other ultrafaint dwarf galaxies, which are believed to be produced by faint supernovae.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Youquan Fu, Michele Cappellari, Shude Mao, Shengdong Lu, Kai Zhu, Ran Li
Summary: We analyzed the integral field spectroscopy data of approximately 10,000 galaxies in the final data release of the MaNGA survey. We found 188 galaxies with emission lines that cannot be described by single Gaussian components. These galaxies can be classified into three categories: (1) 38 galaxies with broad H alpha and [O III] lambda 5007 lines, (2) 101 galaxies with broad H alpha lines but no broad [O III] lambda 5007 lines, and (3) 49 galaxies with double-peaked narrow emission lines. Most of the broad-line galaxies are active galactic nuclei (AGNs) according to their line ratios. The catalog provides insights into AGN-galaxy coevolution and the relationship between broad-line properties and host galaxies' dynamical properties.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Jindra Gensior, Timothy A. Davis, Martin Bureau, J. M. Diederik Kruijssen, Michele Cappellari, Ilaria Ruffa, Thomas G. Williams
Summary: Observations show that the central gas discs in early-type galaxies are smoother than those in late-type galaxies. Simulations suggest that the suppression of fragmentation in spheroid-dominated galaxies is due to the shear-induced turbulence. Power spectrum slope analysis indicates that high shear can lead to incompressible turbulence.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(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)
Article
Astronomy & Astrophysics
Michele Cappellari
Summary: This study introduces improvements to the ppxf method in measuring the kinematics, star formation history, and chemical composition of galaxies. The updated ppxf method shows more reliable estimates for stellar population mass and reveals relationships between galaxy age, metallicity, and stellar velocity dispersion. The comparison with different model assumptions demonstrates the importance of model comparisons in interpreting the results.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Jesus Dominguez-Gomez, Isabel Perez, Tomas Ruiz-Lara, Reynier F. Peletier, Patricia Sanchez-Blazquez, Ute Lisenfeld, Jesus Falcon-Barroso, Manuel Alcazar-Laynez, Maria Argudo-Fernandez, Guillermo Blazquez-Calero, Helene Courtois, Salvador Duarte Puertas, Daniel Espada, Estrella Florido, Ruben Garcia-Benito, Andoni Jimenez, Kathryn Kreckel, Monica Relano, Laura Sanchez-Menguiano, Thijs van der Hulst, Rien van de Weygaert, Simon Verley, Almudena Zurita
Summary: Galaxies in voids exhibit distinct properties compared to those in denser large-scale environments, such as being bluer, less massive, later in morphology, and having higher star formation rates. However, it has not been proven observationally that the star formation histories in voids differ substantially from other environments. This study reveals that void galaxies have undergone slower star formation histories on average compared to galaxies in filaments, walls, and clusters.
Article
Astronomy & Astrophysics
K. E. Harborne, A. Serene, E. J. A. Davies, C. Derkenne, S. Vaughan, A. I. Burdon, C. del P. Lagos, R. Mcdermid, S. O'Toole, C. Power, A. S. G. Robotham, G. Santucci, R. Tobar
Summary: This work presents a methodology and code-base for constructing mock IFS observations of simulated galaxies, aiming to improve collaboration and comparison between observation and theory, and accelerate our understanding of galaxy kinematics evolution. The open-source package SimSpin, written in R, can be interacted with in any coding language via an API interface and is being utilized by international IFS collaborations.
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF AUSTRALIA
(2023)