Massive bulges are not just ellipticals surrounded by disks

AbstractUsing results from parametric multi-component multi-band image fitting of 1000 local massive galaxies in the SDSS, I investigate scaling relations of elliptical galaxies and bulges of disk galaxies. I show that ellipticals and bulges occupy different loci in both the edge-on and face-on views of the fundamental plane. In addition, ellipticals and bulges have offset mass-size relations (see Fig. 1). These results imply that massive bulges are not just massive ellipticals with a surrounding disk, a misconception driven by early studies. This is evidence that massive ellipticals and bulges have different formation histories, with important consequences for studies on galaxy formation and evolution. Full details can be seen in Gadotti (2009).

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Disk Galaxies in the Magneticum Pathfinder Simulations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314009491 ◽

2014 ◽

Vol 10 (S309) ◽

pp. 145-148 ◽

Cited By ~ 3

Author(s):

Rhea-Silvia Remus ◽

Klaus Dolag ◽

Lisa K. Bachmann ◽

Alexander M. Beck ◽

Andreas Burkert ◽

...

Keyword(s):

Galaxy Formation ◽

Mass Function ◽

Disk Galaxies ◽

Physical Processes ◽

Galaxy Formation And Evolution ◽

Mass Size ◽

Formation And Evolution ◽

Galaxy Populations ◽

Size Relation ◽

The Universe

AbstractWe presentMagneticum Pathfinder, a new set of hydrodynamical cosmological simulations covering a large range of cosmological scales. Among the important physical processes included in the simulations are the chemical and thermodynamical evolution of the diffuse gas as well as the evolution of stars and black holes and the corresponding feedback channels. In the high resolution boxes aimed at studies of galaxy formation and evolution, populations of both disk and spheroidal galaxies are self-consistently reproduced. These galaxy populations match the observed stellar mass function and show the same trends for disks and spheroids in the mass–size relation as observations from the SDSS. Additionally, we demonstrate that the simulated galaxies successfully reproduce the observed specific angular-momentum–mass relations for the two different morphological types of galaxies. In summary, theMagneticum Pathfindersimulations are a valuable tool for studying the assembly of cosmic and galactic structures in the universe.

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Past, Present, and Future of the Scaling Relations of Galaxies and Active Galactic Nuclei

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2021.694554 ◽

2021 ◽

Vol 8 ◽

Author(s):

Mauro D’Onofrio ◽

Paola Marziani ◽

Cesare Chiosi

Keyword(s):

Active Galactic Nuclei ◽

Galaxy Formation ◽

Galactic Nuclei ◽

Scaling Relations ◽

Short History ◽

Physical Mechanisms ◽

Galaxy Formation And Evolution ◽

The Galaxy ◽

History Of ◽

Formation And Evolution

We review the properties of the established Scaling Relations (SRs) of galaxies and active galactic nuclei (AGN), focusing on their origin and expected evolution back in time, providing a short history of the most important progresses obtained up to now and discussing the possible future studies. We also try to connect the observed SRs with the physical mechanisms behind them, examining to what extent current models reproduce the observational data. The emerging picture clarifies the complexity intrinsic to the galaxy formation and evolution process as well as the basic uncertainties still affecting our knowledge of the AGN phenomenon. At the same time, however, it suggests that the detailed analysis of the SRs can profitably contribute to our understanding of galaxies and AGN.

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Spatially resolving the relics: The inferring the physics driving the quenching of massive galaxies from kinematics at z ∼ 1 and beyond

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320001222 ◽

2019 ◽

Vol 15 (S352) ◽

pp. 267-267

Author(s):

Rachel Bezanson

Keyword(s):

Star Formation ◽

Galaxy Formation ◽

High Redshift ◽

Elliptical Galaxies ◽

Spectroscopic Studies ◽

Gas Reservoirs ◽

Massive Galaxies ◽

Spatially Resolved ◽

Galaxy Formation And Evolution ◽

Ordered Motion

AbstractToday's massive elliptical galaxies are primarily red-and-dead, dispersion supported ellipticals. The physical process(es) driving the shutdown or ‘quenching’ of star formation in these galaxies remains one of the least understood aspects of galaxy formation and evolution. Although today's spiral and elliptical galaxies exhibit a clear bimodality in their structures, kinematics, and stellar populations, it may be that the quenching and structural transformation do no occur simultaneously. In this talk I will present evidence that early quiescent galaxies, observed much closer to their quenching epoch at z ∼ 1, retain significant rotational support (∼ twice as much as local ellipticals). This suggests that the mechanisms responsible for shutting down star formation do not also have to destroy ordered motion in massive galaxies; the increased dispersion support could occur subsequently via hierarchical growth and minor merging. I will discuss this evidence in conjunction with recent ALMA studies of the dramatic range in molecular gas reservoirs of recently quenched high redshift galaxies to constrain quenching models. Finally, I will discuss prospects for extending spatially resolved spectroscopic studies of galaxies immediately following quenching with JWST and eventually 30-m class telescopes.

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Direct Evidence for AGN-Driven Winds in a z = 1.5 Radio Galaxy

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310006915 ◽

2009 ◽

Vol 5 (S267) ◽

pp. 407-407

Author(s):

Eric Steinbring

Keyword(s):

Adaptive Optics ◽

Galaxy Formation ◽

Direct Evidence ◽

Radio Galaxy ◽

Massive Galaxies ◽

Radio Jets ◽

Galaxy Formation And Evolution ◽

Formation And Evolution ◽

Integral Field Spectrograph ◽

Good Agreement

Feedback from AGN is a key component in most current models of galaxy formation and evolution. For the most massive galaxies, heating and removal of gas by the AGN could precipitate an abrupt quenching of star formation during a dramatic blow-out phase. The “smoking gun” for such a scenario would be direct evidence of powerful outflows associated with the jet. I present some preliminary results of a program to look for these in high-z radio galaxies (HzRGs). Recent observations of the z = 1.5 radio galaxy 3C 230 obtained with the NIFS integral-field spectrograph and Altair laser adaptive optics facility on Gemini North are shown. These reveal with unprecedented resolution the complex kinematics of this system in redshifted Hα and [N ii] emission. The bi-polar velocity field is aligned with the jet axis, with a kinematic center associated with the radio core itself, and turbulent edges approaching the galaxy's escape velocity. This suggests a gas mass of roughly 1011M⊙ has been propagating outwards for 107 to 108 years, corresponding to a mass loss of roughly 102–3M⊙ yr−1, based on its velocity and spatial extent. This is in good agreement with the energetics and typical ages of radio jets, and likely heralds the onset of the “red and dead” stage for this HzRG.

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Scale Length of Disk Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311023027 ◽

2010 ◽

Vol 6 (S277) ◽

pp. 317-320

Author(s):

Kambiz Fathi

Keyword(s):

Galaxy Formation ◽

Surface Brightness ◽

Sloan Digital Sky Survey ◽

Disk Galaxies ◽

Test Bed ◽

Massive Galaxies ◽

Central Surface ◽

Galaxy Formation And Evolution ◽

The Galaxy ◽

Scale Length

AbstractDisk scale length rd and central surface brightness μ0 for a sample of 29955 bright disk galaxies from the Sloan Digital Sky Survey have been analyzed. Cross correlation of the SDSS sample with the LEDA catalogue allowed us to investigate the variation of the scale lengths for different types of disk/spiral galaxies and present distributions and typical trends of scale lengths all the SDSS bands with linear relations that indicate the relation that connect scale lengths in one passband to another. We use the volume corrected results in the r-band and revisit the relation between these parameters and the galaxy morphology, and find the average values 〈rd〉 = 3.8 ± 2.1 kpc and 〈μ0〉 = 20.2 ± 0.7 mag arcsec−2. The derived scale lengths presented here are representative for a typical galaxy mass of 1010.8 M⊙, and the RMS dispersion is larger for more massive galaxies. We analyse the rd–μ0 plane and further investigate the Freeman Law and confirm that it indeed defines an upper limit for μ0 in bright disks (rmag < 17.0), and that disks in late type spirals (T ≥ 6) have fainter central surface brightness. Our results are based on a sample of galaxies in the local universe (z < 0.3) that is two orders of magnitudes larger than any sample previously studied, and deliver statistically significant results that provide a comprehensive test bed for future theoretical studies and numerical simulations of galaxy formation and evolution.

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Trends in Galaxy Formation and Evolution in the Context of the Virial and Fundamental Planes

Symposium - International Astronomical Union ◽

10.1017/s0074180900112550 ◽

1999 ◽

Vol 186 ◽

pp. 195-195

Author(s):

Tapan K. Chatterjee ◽

V.B. Magalinsky

Keyword(s):

Galaxy Formation ◽

Homogeneous Medium ◽

Parametric Form ◽

Subsequent Evolution ◽

Scale Separation ◽

Small Perturbations ◽

Fundamental Plane ◽

Galaxy Formation And Evolution ◽

Formation And Evolution ◽

Gravitating Systems

The kinetic description of gravitating systems has acquired vital importance in the context of trends in galaxy formation and evolution as evidenced by the existence of the virial and fundamental planes. The fundamental plane deviates for brighter and fainter ellipticals; until the brightest cluster members (BCMs), whose structures have been most modified by interactions, seem to occupy a fundamental plane with a different slope as compared to normal ellipticals. Extending the work of Magalinsky (1972, AZh, 49, 1017; Sov. Astron.-AJ, 16, 830), the Vlasov equation is applied to study small perturbations (considered as protogalaxies) of the exact solution corresponding to a spatially homogeneous medium in expansion. It is found that a perturbation attains a saturated size whose scale length, as a function of a reduced parameter of evolution (in terms of the characteristic frequency of dispersion of momenta, τ), R(τ) ∝ K.E./P.E. ∝ (K.E.)2/σ ∝ (δV)2/Proj.density ∝ σ2/I, which has the parametric form of the virial plane. The subsequent evolution is characterized principally by the variation of the energy due to the gravitational interactions between stars (considered as mass points), given by the potential energy such that the harmonic mean separation scale (between stars) characterizes this evolution. In this stage of the evolution the harmonic scale separation has the parametric form, 〈r−1〉 ∝ (K.E.)1/2, and 〈r−1〉 ∝ (P-E.) such that 〈r−1〉 ∝ (K.E.)1/2/(P.E.) ∝ σ/I. Notice that this is the parametric form of the fundamental plane of evolved ellipticals since the harmonic scale separation determines a physically significant scale.

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The radial distribution in nearby galaxies of the ionizing field of radiation of hii regions using photoionization models

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319004241 ◽

2018 ◽

Vol 14 (A30) ◽

pp. 258-258

Author(s):

Enrique Pérez-Montero ◽

Rubén García-Benito ◽

José M. Vílchez

Keyword(s):

Galaxy Formation ◽

Radial Distribution ◽

Disk Galaxies ◽

Ionized Gas ◽

Local Universe ◽

Galaxy Formation And Evolution ◽

Nearby Galaxies ◽

Formation And Evolution ◽

Ionization Parameter

AbstractHii regions in galaxy disks can be used as a powerful tool to trace the radial distribution of several of their properties and shed some light on the different relevant processes on galaxy formation and evolution. Among the properties that can be extracted from the study of the ionized gas are the metallicity, the excitation and the hardness of the ionizing field of radiation. In this contribution we focus on the determination of both the ionization parameter (U) and the effective temperature of the ionizing clusters (T) by means of a bayesian-like comparison between the observed relative fluxes of several emission-lines with the predictions from a set of photoionization models. We also show the implications that the use of our method has for the study of the radial variation of both U and T in some very well-studied disk galaxies of the Local Universe.

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Comparing the star formation history of three nearby disk galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318003927 ◽

2018 ◽

Vol 14 (S344) ◽

pp. 271-273

Author(s):

Ruixiang Chang ◽

Xiaoyu Kang ◽

Fenghui Zhang

Keyword(s):

Star Formation ◽

Galaxy Formation ◽

Local Environment ◽

Star Formation History ◽

Disk Galaxies ◽

Galaxy Formation And Evolution ◽

Formation History ◽

History Of ◽

Formation And Evolution ◽

Later Phase

AbstractUnderstanding the effect of environment on galaxy formation and evolution is one of the hot topics in extragalactic astronomy. Here we constructed a chemical evolution model of disk galaxies. By comparing the model predictions with the observed profiles, we investigated the star formation history of M33, NGC 300 and NGC 2403. We found that M33 has much longer infall timescale than NGC 300 and NGC 2403, and the star formation process of M33 is still active at later phase. Our results suggested that the cold gas supply of M33 is sufficient in the present-day, which may originate from the HI bridge between M33 and M31. In other words, we argue that the local environment plays an important role on the star formation history of a galaxy, at least for M33.

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Searching for Ultra-diffuse galaxies in the low-density environment around NGC 3115

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320001957 ◽

2019 ◽

Vol 15 (S359) ◽

pp. 257-259

Author(s):

Marco Canossa-Gosteinski ◽

Ana L. Chies-Santos ◽

Cristina Furlanetto ◽

Rodrigo F. Freitas ◽

William Schoenell

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Visual Inspection ◽

Milky Way ◽

Structural Parameters ◽

Low Density ◽

Massive Galaxies ◽

Galaxy Formation And Evolution ◽

Formation And Evolution

AbstractUltra-diffuse galaxies (UDGs) are extremely low luminosity galaxies and some of them seem to have a lack of dark matter. Therefore, they can offer important clues to better understand galaxy formation and evolution. Little is known about UDGs in less dense environments, as most of the known UDGs have been found in very dense regions, in the outskirts of massive galaxies in galaxy clusters. In this work, we present the properties of UDGs candidates identified through visual inspection around the low-density environment of NGC 3115, the closest S0 galaxy from the Milky Way. We have measured the structural parameters of 41 UDGs candidates using images obtained with the Dark Energy Camera at the Blanco Telescope. Such structural parameters will be used to characterise and select the best UDG candidates, that will have their properties traced for future follow-up campaigns.

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A Precise Benchmark for Cluster Scaling Relations: Fundamental Plane, Mass Plane and IMF in the Coma Cluster from Dynamical Models

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1043 ◽

2020 ◽

Cited By ~ 2

Author(s):

Shravan Shetty ◽

Michele Cappellari ◽

Richard M McDermid ◽

Davor Krajnović ◽

P T de Zeeuw ◽

...

Keyword(s):

Galaxy Formation ◽

Scaling Relations ◽

Coma Cluster ◽

Dynamical Models ◽

Fundamental Plane ◽

Cluster Galaxies ◽

Dynamical Scaling ◽

Small Uncertainty ◽

Cluster Distance ◽

Using Data

Abstract We study a sample of 148 early-type galaxies in the Coma cluster using SDSS photometry and spectra, and calibrate our results using detailed dynamical models for a subset of these galaxies, to create a precise benchmark for dynamical scaling relations in high-density environments. For these galaxies, we successfully measured global galaxy properties, modeled stellar populations, and created dynamical models, and support the results using detailed dynamical models of 16 galaxies, including the two most massive cluster galaxies, using data taken with the SAURON IFU. By design, the study provides minimal scatter in derived scaling relations due to the small uncertainty in the relative distances of galaxies compared to the cluster distance. Our results demonstrate low (≤55% for 90th percentile) dark matter fractions in the inner 1Re of galaxies. Owing to the study design, we produce the tightest, to our knowledge, IMF-σe relation of galaxies, with a slope consistent with that seen in local galaxies. Leveraging our dynamical models, we transform the classical Fundamental Plane of the galaxies to the Mass Plane. We find that the coefficients of the mass plane are close to predictions from the virial theorem, and have significantly lower scatter compared to the Fundamental plane. We show that Coma galaxies occupy similar locations in the (M* - Re) and (M* - σe) relations as local field galaxies but are older. This, and the fact we find only three slow rotators in the cluster, is consistent with the scenario of hierarchical galaxy formation and expectations of the kinematic morphology-density relation.

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