Early-type galaxy distances from the Fundamental Plane and surface brightness fluctuations

Within the hierarchical CDM framework, gas-poor mergers contribute substantially to the building of the most massive galaxies (Faber et al. 2007). We want to test this scenario by studying the fundamental plane (FP) and the stellar populations of the most massive galaxies. We investigate a well-defined sample of massive early-type galaxies at 0.1<z<0.4, identified from the SDSS database. Out of 42,000 possible targets in the SDSS database, we extracted 23 luminous early-type galaxies with bona fide high velocity dispersions of σ>350 km s−1. These systems are located either in high or low-density environments and show a variety of small surface-brightness structure. Using archival HST/ACS images and Gemini/GMOS spectroscopy, we will explore the photometric and spectroscopic properties of these galaxies.

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Near-IR Imaging of Elliptical Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900109556 ◽

1995 ◽

Vol 164 ◽

pp. 443-443 ◽

Cited By ~ 1

Author(s):

M.A. Pahre ◽

S. Djorgovski ◽

K. Matthews ◽

D. Shupe ◽

R. De Carvalho ◽

...

Keyword(s):

Surface Brightness ◽

Stellar Population ◽

Elliptical Galaxies ◽

Virgo Cluster ◽

Fundamental Plane ◽

Near Ir ◽

Surface Brightness Fluctuations ◽

Distance Indicator ◽

Color Gradients ◽

Optical Color

We have imaged more than thirty early-type galaxies in the K-band to investigate their stellar populations. Our surface brightness fluctuations (SBF) measurements for the nearest 14 galaxies produce a mean fluctuations magnitude in the K-band of The scatter in the Virgo cluster is small at 0.18 mag, which implies that infrared SBF is potentially a good distance indicator (Pahre & Mould 1994). Inspection of the simple stellar population tracks of Worthey (1994) suggests that a plot of the fluctuation color against broadband color (V – I) might be useful in discriminating between age and metallicity effects in elliptical galaxies. We have measured (r – K) color gradients for the entire sample utilizing three methods, two of them independent of sky-subtraction errors, as found in Sparks & Jørgensen (1993). Our color gradients are consistent with a mean metallicity gradient of 0.14 mag dex−1, which is somewhat smaller than that implied by optical color and line gradients alone, suggesting that age gradients may also be important. Finally, we have constructed an infrared Fundamental Plane (FP) which is consistent with its optical counterpart; continued work will determine if there is a significant change in the tilt of the FP between the optical and infrared.

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A rare example of low surface-brightness radio lobes in a gas-rich early-type galaxy: the story of NGC 3998

Astronomy and Astrophysics ◽

10.1051/0004-6361/201628282 ◽

2016 ◽

Vol 592 ◽

pp. A94 ◽

Cited By ~ 7

Author(s):

Bradley S. Frank ◽

Raffaella Morganti ◽

Tom Oosterloo ◽

Kristina Nyland ◽

Paolo Serra

Keyword(s):

Surface Brightness ◽

Early Type ◽

Low Surface Brightness ◽

Early Type Galaxy

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Scaling relations in early-type galaxies from integral-field stellar kinematics

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310008343 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 81-81

Author(s):

M. Cappellari ◽

N. Scott ◽

K. Alatalo ◽

L. Blitz ◽

M. Bois ◽

...

Keyword(s):

Surface Brightness ◽

Velocity Dispersion ◽

Scaling Relations ◽

Early Type ◽

Stellar Kinematics ◽

Fundamental Plane ◽

The Past ◽

Stellar Velocity ◽

Integral Field ◽

Significant Effort

Early-type galaxies (ETGs) satisfy a now classic scaling relation Re ∝ σ1.2eI−0.8e, the Fundamental Plane (FP; Djorgovski & Davis 1987; Dressler et al. 1987), between their size, stellar velocity dispersion and mean surface brightness. A significant effort has been devoted in the past twenty years to try to understand why the coefficients of the relation are not the ones predicted by the virial theorem Re ∝ σ2eI−1e.

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Scaling relations of early-type galaxies in the 6dF Galaxy Survey

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310008379 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 84-84

Author(s):

C. Magoulas ◽

M. Colless ◽

H. Jones ◽

J. Mould ◽

C. Springob

Keyword(s):

Surface Brightness ◽

Near Infrared ◽

Velocity Dispersion ◽

Three Dimensional ◽

Gaussian Model ◽

Early Type ◽

Fundamental Plane ◽

Infrared Wavelengths ◽

Observational Errors ◽

Intrinsic Scatter

Over 10,000 early-type galaxies from the 6dF Galaxy Survey (6dFGS) (Jones, D. H. et al. (2009), Jones et al. (2004)) have been used to determine the Fundamental Plane at optical and near-infrared wavelengths. We find that a maximum likelihood fit to an explicit three-dimensional Gaussian model for the distribution of galaxies in size, surface brightness and velocity dispersion can precisely account for selection effects, censoring and observational errors, leading to precise and unbiased parameters for the Fundamental Plane and its intrinsic scatter.

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The first detection of ultra-diffuse galaxies in the Hydra I cluster from the VEGAS survey

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038523 ◽

2020 ◽

Vol 642 ◽

pp. A48

Author(s):

E. Iodice ◽

M. Cantiello ◽

M. Hilker ◽

M. Rejkuba ◽

M. Arnaboldi ◽

...

Keyword(s):

Surface Brightness ◽

Total Population ◽

Matter Content ◽

Early Type ◽

Low Surface Brightness ◽

Colour Distribution ◽

Specific Frequency ◽

Stellar Masses ◽

Low Surface Brightness Galaxies ◽

Early Type Galaxy

In this paper, we report the discovery of 27 low-surface brightness galaxies, of which 12 are candidates for ultra-diffuse galaxies (UDG) in the Hydra I cluster, based on deep observations taken as part of the VST Early-type Galaxy Survey (VEGAS). This first sample of UDG candidates in the Hydra I cluster represents an important step in our project that aims to enlarge the number of confirmed UDGs and, through study of statistically relevant samples, constrain the nature and formation of UDGs. This study presents the main properties of this class of galaxies in the Hydra I cluster. For all UDGs, we analysed the light and colour distribution, and we provide a census of the globular cluster (GC) systems around them. Given the limitations of a reliable GC selection based on two relatively close optical bands only, we find that half of the UDG candidates have a total GC population consistent with zero. Of the other half, two galaxies have a total population larger than zero at 2σ level. We estimate the stellar mass, the total number of GCs, and the GC specific frequency (SN). Most of the candidates span a range of stellar masses of 107 − 108 M⊙. Based on the GC population of these newly discovered UDGs, we conclude that most of these galaxies have a standard or low dark matter content, with a halo mass of ≤1010 M⊙.

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Fundamental Plane and Merger Scenario

Symposium - International Astronomical Union ◽

10.1017/s0074180900112501 ◽

1999 ◽

Vol 186 ◽

pp. 185-188

Author(s):

K. Bekki

Keyword(s):

Surface Brightness ◽

Velocity Dispersion ◽

Evolutionary Process ◽

Elliptical Galaxies ◽

Scaling Relation ◽

Early Type ◽

Dynamical Mass ◽

Fundamental Plane ◽

Apparent Deviation ◽

The Mean

The Fundamental Plane (FP) is one of the most important universal relations in early type galaxies because it contains valuable information about the formative and evolutionary process of galaxies (Djorgovski & Davis 1987, Dressler et al. 1987). The commonly used form of the scaling relation in the FP is described as Re = σAIB, where Re, σ, and I are effective radius, central velocity dispersion, and mean surface brightness of elliptical galaxies, respectively. The exponents A, B are considered to be 1.56 ± 0.07 and −0.94 ± 0.09 in the FP derived by K band photometry, respectively, and these values deviate significantly from the values A = 2.0 and B = −1.0 expected from virial theorem (Pahre et al. 1995; Djorgovski, Pahre, & de Carvalho 1996). This apparent deviation requires that the ratio of dynamical mass (M) to luminosity of elliptical galaxies (L) depends on M as M/L ∝ Mα (α = 0.12 ± 0.03 for K band). Possible interpretations for the required dependence of M/L on M are generally considered to be divided into the following two. One is that the required dependence of M/L on M results from the fact that the mean stellar age and metalicity of elliptical galaxies depend systematically on M. The other is that the required dependence reflects the M dependence of structural and kinematical properties of elliptical galaxies (“nonhomology”). Although we should not neglect the importance of stellar populations in generating the M dependence of the M/L (Renzini & Ciotti 1993), we here consider that the origin of the required M dependence of M/L is closely associated with the structural and kinematical properties dependent on M or L in elliptical galaxies.

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Chandra Early-Type Galaxy Atlas

Proceedings of the International Astronomical Union ◽

10.1017/s174392131800594x ◽

2018 ◽

Vol 14 (S342) ◽

pp. 242-243

Author(s):

Dong-Woo Kim ◽

Craig Anderson ◽

Douglas Burke ◽

Raffaele D’Abrusco ◽

Giuseppina Fabbiano ◽

...

Keyword(s):

Surface Brightness ◽

Structural Features ◽

Early Type ◽

Evolutionary Mechanisms ◽

Hot Gas ◽

Spatially Resolved ◽

Data Products ◽

Formation And Evolution ◽

High Level ◽

Early Type Galaxy

AbstractThe hot ISM in early-type galaxies (ETGs) plays a crucial role in understanding their formation and evolution. The structural features of the hot gas identified by Chandra observations point to key evolutionary mechanisms, (e.g., kim12). In our Chandra Galaxy Atlas (CGA) project, taking full advantage of the Chandra capabilities, we systematically analyzed the archival Chandra data of 72 ETGs and produced uniform data products of the hot gas properties. The main data products include spatially resolved 2D spectral maps of the hot gas from individual galaxies. We emphasize that new features can be identified in the spectral maps which are not easily visible in the surface brightness maps. The high-level images can be viewed at the dedicated CGA website, and the CGA data products can be downloaded to compare with other wavelength data and to perform user-specific analyses. Utilizing our data products, we will further address focused science topics.

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Measuring the Evolution of the M/L Ratio from the Fundamental Plane

Symposium - International Astronomical Union ◽

10.1017/s0074180900108654 ◽

1995 ◽

Vol 164 ◽

pp. 269-274

Author(s):

Marijn Franx

Keyword(s):

Star Formation ◽

Surface Brightness ◽

Star Formation History ◽

Early Type ◽

Fundamental Plane ◽

Formation History ◽

Sensitive Tool ◽

The Imf

The Fundamental plane provides a sensitive tool to measure the change in the M/L ratio of early type galaxies with redshift. The evolution of the M/L ratio is a function of the star formation history. It depends on the IMF, the formation redshift, and cosmology. Some model examples are shown, and a first result on the cluster Abell 665 at z=0.18 is given. The measurements confirm the cosmological surface brightness dimming, and imply an evolution of the (red) L/M ratio ∝ (1 + z)1,8±0,7. More data are needed to extend this result to higher redshifts, and to test the underlying assumptions.

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An HST Survey of Cores of Early-Type Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900232221 ◽

1996 ◽

Vol 171 ◽

pp. 105-116 ◽

Cited By ~ 1

Author(s):

John Kormendy ◽

Yong-Ik Byun ◽

E. A. Ajhar ◽

Tod R. Lauer ◽

Alan Dressler ◽

...

Keyword(s):

Outer Surface ◽

Surface Brightness ◽

Hubble Space Telescope ◽

Elliptical Galaxies ◽

Core Radius ◽

Early Type ◽

Late Type ◽

Fundamental Plane ◽

The Core ◽

Oblate Spheroidal

Photometry of the central parts of bulges and elliptical galaxies with the Hubble Space Telescope (HST) confirms and extends ground-based results. Most giant ellipticals have cuspy cores: at the “break radius” rb (formerly the core radius rc), the steep outer surface brightness profile turns down to a shallow inner power law I(r) ∝ r–γ, 0 ≤ γ ≲ 0.25. The corresponding slope of the deprojected profile is derived; the flattest cores allow box orbits to survive. Cores continue to satisfy fundamental plane parameter correlations like those found from the ground. In particular, HST confirms that the luminosity sequence of elliptical galaxies (from cDs to M 32) is physically unrelated to spheroidal galaxies like Fornax. The latter are closely related to late-type dwarfs. Low-luminosity ellipticals do not show cores: 0.5 ≲ γ ≲ 1.3. The most important new result is that global and core properties both show signs of a dichotomy between (i) low-luminosity ellipticals that rotate rapidly, that are nearly isotropic and oblate-spheroidal, that have disky-distorted isophotes, and that are coreless and (ii) giant ellipticals that are essentially nonrotating, anisotropic, and moderately triaxial, that are boxy-distorted, and that have cuspy cores.

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