Reconstructing the velocity dispersion profiles from the line-of-sight kinematic data in disc galaxies

Abstract

We present a modification of the method for reconstructing the stellar velocity ellipsoid (SVE) in disc galaxies. Our version does not need any parametrization of the velocity dispersion profiles and uses only one assumption that the ratio ${\sigma }_z/{\sigma }_R$ remains constant along the profile or along several pieces of the profile. The method was tested on two galaxies from the sample of other authors and for the first time was applied to three lenticular galaxies NGC~1167, NGC~3245 and NGC~4150 as well as to one Sab galaxy NGC~338. We found that for galaxies with a high inclination ($i>55-60^{\circ }$) it is difficult or rather impossible to extract the information about SVE while for galaxies at an intermediate inclination the procedure of extracting is successful. For NGC~1167 we managed to reconstruct SVE, provided that the value of ${\sigma }_z/{\sigma }_R$ is piecewise constant. We found ${\sigma }_z/{\sigma }_R=0.7$ for the inner parts of the disc and ${\sigma }_z/{\sigma }_R=0.3$ for the outskirts. We also obtained a rigid constrain on the value of the radial velocity dispersion ${\sigma }_R$ for highly inclined galaxies and tested the result using the asymmetric drift equation, provided that the gas rotation curve is available.

References in corpus (31)

• Local stellar kinematics from Hipparcos data
• A direct dynamical measurement of the Milky Way's disk surface density profile, disk scale length, and dark matter profile at 4 kpc < R < 9 kpc
• The SCORPIO focal reducer
• Evolutionary synthesis of galaxies at high spectral resolution with the code PEGASE-HR
• Triaxial orbit based galaxy models with an application to the (apparent) decoupled core galaxy NGC 4365
• Bulges Of Nearby Galaxies With Spitzer: Scaling Relations in Pseudobulges and Classical Bulges
• Made-to-measure N-body systems
• Radial Migration Does Little for Galactic Disc Thickening
• The Westerbork HI Survey of spiral and irregular galaxies III: HI observations of early-type disk galaxies
• The mass distribution in early-type disk galaxies: declining rotation curves and correlations with optical properties
• NMAGIC: Fast Parallel Implementation of a Chi-Squared-Made-to-Measure Algorithm for Modelling Observational Data
• The DiskMass Survey. VI. Gas and stellar kinematics in spiral galaxies from PPak integral-field spectroscopy
• The Disk Mass project; science case for a new PMAS IFU module
• Dark matter content and internal dynamics of NGC 4697: NMAGIC particle models from slit data and planetary nebulae velocities
• Observational Constraints on Disk Heating as a Function of Hubble Type
• Structure and kinematics of edge-on galaxy discs -- V. The dynamics of the stellar discs
• Kinematic Signatures of Bulges Correlate with Bulge Morphologies and Sérsic Index
• A clear age-velocity dispersion correlation in Andromeda's stellar disk
• An Iterative Method for Constructing Equilibrium Phase Models of Stellar Systems
• The shape of the velocity ellipsoid in NGC 488
• Disc heating in NGC 2985
• Self-consistent models of cuspy triaxial galaxies with dark matter haloes
• Disk heating agents across the Hubble sequence
• The stellar mass distribution in early-type disk galaxies: surface photometry and bulge-disk decompositions
• Cold gas in group-dominant elliptical galaxies
• An investigation of the structure and kinematics of the spiral galaxy NGC 6503
• Large scale nested stellar discs in NGC 7217
• Bending instability in galactic discs. Advocacy of the linear theory
• An Iterative Method for the Construction of Equilibrium N-Body Models for Stellar Disks
• Exploring Disk Galaxy Dynamics Using IFU Data
• Kinematics and Stellar Disk Modeling of Lenticular Galaxies

Cited by in corpus (8)

• The specific angular momentum of disc galaxies and its connection with galaxy morphology, bar structure and disc gravitational instability
• Resolving Quiescent Galaxies at $z\gtrsim 2$: II. Direct Measures of Rotational Support
• From lenticulars to blue compact dwarfs: the stellar mass fraction is regulated by disc gravitational instability
• Angular momentum and local gravitational instability in galaxy discs: does $Q$ correlate with $j$ or $M$?
• Gravitational instability and star formation in NGC 628
• Two-component gravitational instability in spiral galaxies
• Local variations of the Stellar Velocity Ellipsoid-I: the disc of galaxies in the Auriga simulations
• Gravitational instability and spatial regularity of the gas clouds and young stellar population in spiral arms of NGC 628