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Related papers: Galaxy surface photometry

200 papers

We present a physically motivated extension of the FP for elliptical galaxies, derived from the scalar virial theorem and calibrated using observational data. Starting from the basic equilibrium condition, we incorporate key physical…

Astrophysics of Galaxies · Physics 2025-11-05 Tarek Yehia

The statistical properties of the ellipticities of galaxy images depend on how galaxies form and evolve, and therefore constrain models of galaxy morphology, which are key to the removal of the intrinsic alignment contamination of…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-28 B. Joachimi , E. Semboloni , P. E. Bett , J. Hartlap , S. Hilbert , H. Hoekstra , P. Schneider , T. Schrabback

A photometric method for quantifying deviations from axisymmetry in optical images of disk galaxies is applied to a sample of 32 face-on and nearly face-on spirals. The method involves comparing the relative fluxes contained within…

Astrophysics · Physics 2009-10-30 David A. Kornreich , Martha P. Haynes , Richard V. E. Lovelace

Star Formation Rates or SFRs are crucial to constrain theories of galaxy formation and evolution. SFRs are usually estimated via spectroscopic observations requiring large amounts of telescope time. We explore an alternative approach based…

Instrumentation and Methods for Astrophysics · Physics 2019-06-07 M. Delli Veneri , S. Cavuoti , M. Brescia , G. Longo , G. Riccio

I present a method for the fast convolution of a model galaxy profile by a point-spread function (PSF) model represented as a pixel grid. The method relies upon three observations: First, most simple radial galaxy profiles of common…

Instrumentation and Methods for Astrophysics · Physics 2021-01-01 Dustin Lang

Early-type galaxies -- slow and fast rotating ellipticals (E-SRs and E-FRs) and S0s/lenticulars -- define a Fundamental Plane (FP) in the space of half-light radius $R_e$, enclosed surface brightness $I_e$ and velocity dispersion…

Astrophysics of Galaxies · Physics 2020-05-13 M. Bernardi , H. Domínguez Sanchez , B. Margalef-Bentabol , F. Nikakhtar , R. K. Sheth

Luminosity profiles of galaxies acting as strong gravitational lenses can be tricky to study. Indeed, strong gravitational lensing images display several lensed components, both point-like and diffuse, around the lensing galaxy. Those…

Astrophysics of Galaxies · Physics 2015-12-23 J. Biernaux , P. Magain , D. Sluse , V. Chantry

Modern spectroscopic surveys can only target a small fraction of the vast amount of photometrically cataloged sources in wide-field surveys. Here, we report the development of a generative AI method capable of predicting optical galaxy…

We demonstrate in this paper the use of asymmetry in conjunction with the integrated (B-V) color of galaxies for physical morphological purposes. We show how color-asymmetry diagrams can be used to distinguish between various types of…

Astrophysics · Physics 2009-10-31 Christopher J. Conselice

We describe a technique that uses radial color gradients in disk galaxies to detect the presence of bulk non-circular motion or elliptical orbits. In a disk galaxy with both a radial color gradient and non-circular motion, isochromes or…

Astrophysics · Physics 2016-08-15 A. C. Quillen , Solange V. Ramírez , Jay A. Frogel

A deep understanding of the Milky Way galaxy, its formation and evolution requires observations of huge numbers of stars. Stellar photometry, therefore, provides an economical method to obtain intrinsic stellar parameters. With the addition…

Solar and Stellar Astrophysics · Physics 2019-01-30 Louise M. Howes , Lennart Lindegren , Sofia Feltzing , Ross P. Church , Thomas Bensby

We are using optical/IR surface brightness fluctuations (SBFs) to validate the latest stellar population synthesis models and to understand the stellar populations of ellipticals. Integrated light and spectra measure only the first moment…

Astrophysics · Physics 2007-05-23 Michael C. Liu , Stephane Charlot , James R. Graham

We present a two-dimensional (2-D) fitting algorithm (GALFIT, Version 3) with new capabilities to study the structural components of galaxies and other astronomical objects in digital images. Our technique improves on previous 2-D fitting…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Chien Y. Peng , Luis C. Ho , Chris D. Impey , Hans-Walter Rix

We describe the application of the `shapelet' linear decomposition of galaxy images to multi-wavelength morphological classification using the $u,g,r,i,$ and $z$-band images of 1519 galaxies from the Sloan Digital Sky Survey. We utilize…

Astrophysics · Physics 2009-11-10 B. C. Kelly , T. A. McKay

The EDGE-CALIFA survey provides spatially resolved optical integral field unit (IFU) and CO spectroscopy for 125 galaxies selected from the CALIFA Data Release 3 sample. The Extragalactic Database for Galaxy Evolution (EDGE) presents the…

The fundamental plane (FP) of galaxies can be recovered in the framework of $f(R)$ gravity avoiding the issues related to dark matter to fit the observations. In particular, the power-law version $f(R)\propto R^n$, resulting from the…

Astrophysics of Galaxies · Physics 2016-10-12 V. Borka Jovanović , S. Capozziello , P. Jovanović , D. Borka

Current and future imaging surveys will measure cosmic shear with a statistical precision that demands a deeper understanding of potential systematic biases in galaxy shape measurements than has been achieved to date. We investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 J. E. Meyers , P. R. Burchat

A major problem in extragalactic astronomy is the inability to distinguish in a robust, physical, and model independent way how galaxy populations are related to each other and to their formation histories. A similar, but distinct, and also…

Astrophysics · Physics 2009-11-07 Christopher J. Conselice

We present a novel approach for classifying star-forming galaxies using photometric images. By utilizing approximately $124,000$ optical color composite images and spectroscopic data of nearby galaxies at $0.01<z<0.06$ from the Sloan…

Astrophysics of Galaxies · Physics 2025-08-01 Kyuseok Oh , M. Dennis Turp

The Carnegie-Irvine Galaxy Survey (CGS) is a comprehensive investigation of the physical properties of a complete, representative sample of 605 bright (B_T <= 12.9 mag) galaxies in the southern hemisphere. This contribution describes the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Zhao-Yu Li , Luis C. Ho , Aaron J. Barth , Chien Y. Peng