A Self-Consistent Dynamical Model for the COBE Detected Galactic Bar

نویسنده

  • HongSheng Zhao
چکیده

A 3D steady state stellar dynamical model for the Galactic bar is constructed with 485 orbit building blocks using an extension of Schwarzschild technique. The weights of the orbits are assigned using the non-negative least square method. The model fits the density profile of the COBE light distribution, the observed solid body stellar rotation curve, the fall-off of minor axis velocity dispersion and the velocity ellipsoid at Baade’s window. We show that the model is stable. Maps and tables of observable velocity moments are made for easy comparisons with observation. The model can also be used to set up equilibrium initial conditions for N-body simulations to study stability. The technique used here can be applied to interpret high quality velocity data of external bulges/bars and galactic nuclei. Subject headings: Galaxy: structure Galaxy: kinematics and dynamics celestial mechanics, stellar dynamics methods: numerical Submitted to Monthly Notices

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Mass Distribution in Our Galaxy

This article summarizes recent work on the luminosity and mass distribution of the Galactic bulge and disk, and on the mass of the Milky Way’s dark halo. A new luminosity model consistent with the COBE NIR data and the apparent magnitude distributions of bulge clump giant stars has bulge/bar length of ' 3.5 kpc, axis ratios of 1:(0.3-0.4):0.3, and short disk scale-length (' 2.1 kpc). Gas-dynami...

متن کامل

The microlensing rate and mass function vs. dynamics of the Galactic bar

With the steady increase of the sample size of observed microlenses towards the central regions of the Galaxy, the main source of the uncertainty in the lens mass will shift from the simple Poisson noise to the intrinsic non-uniqueness of our dynamical models of the inner Galaxy, particularly, the Galactic bar. We use a set of simple self-consistent bar models to investigate how the microlensin...

متن کامل

3D self-consistent N -body barred models of the Milky Way II. Gas dynamics

The gas dynamics in the Galactic disc is modeled by releasing an initially axisymmetric SPH component in a completely self-consistent and symmetry-free 3D N -body simulation of the Milky Way in which the stellar components display a COBE-like bar. The density centre of the stellar bar wanders around the centre of mass and the resulting gas flow is asymmetric and non-stationary, reproducing the ...

متن کامل

3 D self - consistent N - body barred models of the Milky Way

The gas dynamics in the Galactic disc is modeled by releasing an initially axisymmetric SPH component in a completely self-consistent and symmetry-free 3D N-body simulation of the Milky Way in which the stellar components display a COBE-like bar. The density centre of the stellar bar wanders around the centre of mass and the resulting gas flow is asym-metric and non-stationary, reproducing the ...

متن کامل

3D self-consistent N-body barred models of the Milky Way I. Stellar dynamics

Many 3DN -body barred models of the Galaxy extending beyond the Solar circle are realised by selfconsistent evolution of various bar unstable axisymmetric models. The COBE/DIRBE K-band map, corrected for extinction, is used to constrain the location of the observer in these models, assuming a constant mass-to-light ratio. The resulting view points in the best matching models suggest that the in...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1995