DEIMOS Keck

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(No Transcript)
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DEIMOS _at_ Keck
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Detailed dynamical studies
Mass distribution underlying stellar systems

• dark halos
• massive black holes
• structure formation

ß 1 (s?/sr)2
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dE's in the Local Group
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• de Rijcke et al. (2006)

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• Geha et al. (in prep.)

NGC 147
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R90
13' x 9'
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dE's in the Local Group

• Simplifying assumptions
• axisymmetry, edge on
• 2-integral DF f(E,Lz)
• constant M/L

Jeans modeling of NGC 147
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dE's in the Local Group

• Simplifying assumptions
• axisymmetry, edge on
• 2-integral DF f(E,Lz)
• constant M/L

Jeans modeling of NGC 147
good fit !!! M/L 8
old to intermediateage stellar population with
no dark matter
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Modeling the kinematics of stellar systems
x,y spatial (light) distribution
v line-of-sight velocity
observations
z
??? ???? tangential velocities (GCs)
x
y
phase-space distribution function
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f (r,v,t) d r d v
spherical system E, L
Integrals of motion
f(r,v)
axisymmetric system E, L , I
z
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simple modeling Jeans, f(E,L ), .
z
geometry (spherical, axisymmetric, ...)
simplifying assumptions
isotropic velocity dispersions
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Schwarzschild (orbit superposition) models
trial gravitational potential F
orbit library sampling (E,Lz,I3) integral space
find weighted superposition of (E,Lz,I3) orbits
that best fits light distribution and kinematics
store orbital properties density and kinematics
as a function of (x,y) on sky
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Storing orbital properties
Orbit Library
Cretton et al. (1999)
Rix et al. (1997)
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Schwarzschild (orbit superposition) models
trial gravitational potential F
orbit library sampling (E,Lz,I3) integral space
find weighted superposition of (E,Lz,I3) orbits
that best fits light distribution and kinematics
store orbital properties density and kinematics
as a function of (x,y) on sky
? supermassive black holes dark halos of
galaxies globular cluster dynamics .. ? Rix et
al. (1997) Gebhardt et al. (2000) Valluri et
al. (2004) - . ? all set up to handle LOSVDs
obtained from continuous datasets
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Continuous vs Discrete Data
Integrated light of unresolved population ?
long slits ? integral field units
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Continuous vs Discrete Data
Integrated light of unresolved population ?
long slits ? integral field units
LOSVDs
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Continuous vs Discrete Data
? Cen (van de Ven et al. 2006)
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Continuous vs Discrete Data
? Cen (van de Ven et al. 2006)
NGC 205 (Geha et al. 2006)

• globular clusters and PNe around giant Es
• galaxy redshifts in clusters of galaxies
• stars near centre of Galactic GCs
• ..

Need tools able to exploit these data
appropriately
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3-integral Schwarzschild code for discrete
datasets

• varying overall rotation

Tests using pseudo-data (axisymmetric) E3 galaxy

• inclination on the sky

• many different input datasets

• Study the recovery of
• distribution function
• mass-to-light ratio
• inclination

(Chanamé, van der Marel, Kleyna, in prep.)
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3-integral Schwarzschild code for discrete
datasets
Recovering the input distribution
function (i.e., orbital structure!!)
(Chanamé, van der Marel, Kleyna, in prep.)
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3-integral Schwarzschild code for discrete
datasets
Recovering the input distribution
function (i.e., orbital structure!!)
non rotating case
rotating case
Schwarzschild fit
Input model
(Chanamé, van der Marel, Kleyna, in prep.)
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Recovering the input distribution
function (i.e., orbital structure!!)
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3-integral Schwarzschild code for discrete
datasets
proper-motions provide additional information
than only-LOS velocities
Recovering the input M/L
(Chanamé, van der Marel, Kleyna, in prep.)
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3-integral Schwarzschild code for discrete
datasets
proper-motions provide additional information
than only-LOS velocities
Recovering the input M/L
(Chanamé, van der Marel, Kleyna, in prep.)
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3-integral Schwarzschild code for discrete
datasets
proper-motions provide additional information
than only-LOS velocities
Recovering the input M/L
(Chanamé, van der Marel, Kleyna, in prep.)
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3-integral Schwarzschild code for discrete
datasets
Recovering the inclination
(Chanamé, van der Marel, Kleyna, in prep.)
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dE's in the Local Group
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• de Rijcke et al. (2006)

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• Geha et al. (in prep.)

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NGC 147
R90
13' x 9'

• Coming soon IMBHs in globular clusters
  dSphs dark halos of giant Es .

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END