中文
相关论文

相关论文: A Photometric Method for Quantifying Asymmetries i…

200 篇论文

I present the mean metallicity distribution of stars in the Milky Way Galaxy based on photometry from the Sloan Digital Sky Survey. I utilize an empirically calibrated set of stellar isochrones developed in previous work to estimate the…

星系天体物理 · 物理学 2019-06-19 Deokkeun An

Surface photometry from 16 HST/WFPC2 fields in the I(F814W) filter is used to derive the distribution of apparent axis ratios for galaxies in progressively fainter magnitude intervals for I<25. We assess the systematic and accidental errors…

天体物理学 · 物理学 2009-10-30 S. C. Odewahn , D. Burstein , R. A. Windhorst

Using a sample of 133 991 galaxies distributed in the sky region $100^{\circ} <\alpha<270^{\circ}$ and $7^{\circ}<\delta<65^{\circ}$, extracted from the SDSS NASA/AMES Value Added Galaxy Catalog (AMES-VAGC), we estimate the fractal…

宇宙学与河外天体物理 · 物理学 2021-05-07 T. Canavesi , T. E. Tapia

Symmetry is an important composition feature by investigating similar sides inside an image plane. It has a crucial effect to recognize man-made or nature objects within the universe. Recent symmetry detection approaches used a smoothing…

计算机视觉与模式识别 · 计算机科学 2017-04-24 Mohamed Elawady , Olivier Alata , Christophe Ducottet , Cecile Barat , Philippe Colantoni

(Abridged) We present a non-parametric cell-based method of selecting highly pure and largely complete samples of spiral galaxies using photometric and structural parameters as provided by standard photometric pipelines and simple shape…

宇宙学与河外天体物理 · 物理学 2015-06-17 M. W. Grootes , R. J. Tuffs , C. C. Popescu , A. S. G. Robotham , M. Seibert , L. S. Kelvin

To analyze the vertical structure of edge-on galaxies, we have used images of a large uniform sample of flat galaxies that have been taken during the 2MASS all-sky survey. The photometric parameters, such as the radial scale length, the…

天体物理学 · 物理学 2009-11-07 Dmitry Bizyaev , Sofija Mitronova

We present a method to obtain quantitative measures of galaxy morphology and apply it to a spectroscopic sample of field galaxies in order to determine the luminosity and stellar mass functions of galactic disks and spheroids. We estimate,…

天体物理学 · 物理学 2009-11-07 A. J. Benson , C. S. Frenk , R. M. Sharples

We map the kinematics of stars in simulated galaxy disks with spiral arms using the velocity ellipsoid vertex deviation (l$_v$). We use test particle simulations, and for the first time, fully self-consistent high resolution N-body models.…

We perform a detailed photometric analysis (bulge-disk-bar decomposition and Concentration-Asymmetry-Clumpiness - CAS parametrization) for a well defined sample of isolated galaxies, extracted from the Catalog of Isolated Galaxies…

天体物理学 · 物理学 2008-12-18 A. Durbala , J. W. Sulentic , R. Buta , L. Verdes-Montenegro

We use deep r-band photometry and Halpha rotation curves for a sample of 290 late-type spirals to model their mass distribution within the optical radius. We examine luminosity profile decompositions into bulge and disk carefully and…

天体物理学 · 物理学 2007-05-23 Adrick H. Broeils , Stephane Courteau

The morphological classification of galaxies is considered a relevant issue and can be approached from different points of view. The increasing growth in the size and accuracy of astronomical data sets brings with it the need for the use of…

星系天体物理 · 物理学 2023-03-01 M. S. Rosito , L. A. Bignone , P. B. Tissera , S. E. Pedrosa

The practice of measuring galaxy distances from their spatial fluctuations in surface brightness is now a decade old. While several past articles have included some review material, this is the first intended as a comprehensive review of…

天体物理学 · 物理学 2016-01-27 John P. Blakeslee , Edward A. Ajhar , John L. Tonry

The nature of galaxy spin is still not fully known. Iye et al (2021) applied a 3D analysis to a dataset of bright SDSS galaxies that was used in the past for photometric analysis. They showed that the distribution of spin directions of…

宇宙学与河外天体物理 · 物理学 2022-10-12 Lior Shamir

We examine different measures of asymmetry for galaxy HI velocity profiles. We introduce the channel-by-channel asymmetry and the velocity-of-equality statistics to quantify profile asymmetries. Using a sample of simulated galaxies, we…

星系天体物理 · 物理学 2020-05-27 N. Deg , S. Blyth , N. Hank , S. Kruger , C. Carignan

We present deep optical imaging of three face-on disk galaxies together with a detailed description of the reduction and calibration methods used, in order to measure the intrinsic shape of their outer stellar edges. Whereas it is now well…

天体物理学 · 物理学 2007-05-23 M. Pohlen , R. -J. Dettmar , R. Luetticke , G. Aronica

We present a new technique for the numerical simulation of axisymmetric systems. This technique avoids the coordinate singularities which often arise when cylindrical or polar-spherical coordinate finite difference grids are used,…

广义相对论与量子宇宙学 · 物理学 2008-11-26 M. Alcubierre , S. Brandt , B. Bruegmann , D. Holz , E. Seidel , R. Takahashi , J. Thornburg

We measure the contribution of galaxy disks to the overall gravitational potential of 30 nearly face-on intermediate-to-late-type spirals from the DiskMass Survey. The central vertical velocity dispersion of the disk stars, sigma(z,R=0), is…

We study how well the complex gas velocity fields induced by massive spiral arms are modelled by the hydrodynamical simulations we used to constrain the dark matter fraction in nearby spiral galaxies (Kranz et al. 2001, 2003). More…

天体物理学 · 物理学 2009-11-10 Adrianne Slyz , Thilo Kranz , Hans-Walter Rix

Galaxy evolution is driven to a large extent by interactions and mergers with other galaxies and the gas in galaxies is extremely sensitive to the interactions. One method to measure such interactions uses the quantified morphology of…

宇宙学与河外天体物理 · 物理学 2015-05-27 B. W. Holwerda , N. Pirzkal , W. J. G. de Blok , A. Bouchard , S-L. Blyth , K. J. van der Heyden , E. C. Elson

Given a foreground galaxy-density field or shear field, its cross-correlation with the shear field from a background population of source galaxies scales with the source redshift in a way that is specific to lensing. Such a source-scaling…

天体物理学 · 物理学 2008-11-26 Jun Zhang , Lam Hui , Albert Stebbins