1. 11/16/2018
Probing the Galactic Potential Using the μarcsec astrometric observations of Disk Stars
T. 　　Sumi　　　 (Nagoya STE)
K.V. 　Johnston (Columbia)
S.　　　Tremaine (IAS)
D.N.　Spergel 　(Princeton)

2. MOA-II1.8m telescope （New Zealand/Mt. John Observatory at NZ, 44S ）
11/16/2018
MOA-II1.8m telescope （New Zealand/Mt. John Observatory at NZ, 44S ）
Mirror : 1.8m
CCD : 8k　x　10k pix.
FOV : 2.2 square deg.

3. MACHO fraction depends on halo model
11/16/2018
MACHO fraction depends on halo model

4. Proper motion
11/16/2018
~300 I-band frames, 4years  ~1mas/yr

5. Streaming motions of the bar
11/16/2018
Streaming motions of the bar
Sun
Color Magnitude Diagram
faint bright
Vrot=~50km/s

6. SIM Key Project: Taking Measure of the Milky Way
11/16/2018
SIM Key Project: Taking Measure of the Milky Way
Steven Majewski (Virginia)
[John Bahcall (IAS)]
Doug Geisler (Concepción)
Wolfgang Gieren (Concepción)
Eva Grebel (Basel)
Carl Grillmair (Caltech)
Kathryn Johnston (Wesleyan)
Ricky Patterson (Virginia)
I. Neill Reid (STScI)
David Spergel (Princeton)
Scott Tremaine (Princeton)
Takahiro Sumi (Princeton)
Jeff Crane (OCIW)
Peter Frinchaboy (Virginia)
Ricardo Muñoz (Virginia)
Clara Moskowitz (Wesleyan)
Christina Hampton (Virginia)
David Nidever (Virginia)
Roberta Johnson (Caltech)
Mei-Yin Chou (Virginia)
Cameron Hummels (Wesleyan)
Mike Siegel (Texas)
Tony Sohn (Korean Astro Obs)
Kyle Westfall (Wisconsin)
David Law (Caltech)
Bill Kunkel (Carnegie)
James Bullock (UC-Irvine)
Rachael Beaton (Virginia)
SIM Science Team Meeting – Washington January 2006

7. KP Proposed Scope (1999)
11/16/2018
Mass Potential of Galaxy (tidal tails & satellites in halo)
Mass and Mass Distribution (shape, radial profile) of MW
“Lumpiness” of the Halo
Dynamics of the Disk
Surface Mass Density (Oort limit)
Milky Way Rotation Curve
Dynamics of the Central Galaxy
Dynamics of Bulge
Orientation and Motions of the Bar
Fundamental and Legacy Measurements
Proper motions of every known MW satellite galaxy & globular
Proper motions for large number of selected open clusters
Solar rotation speed, p & dynamical distance to GC

8. Halo & Disk model Halo mass: Disk density: Radial dispersion:
11/16/2018
Halo & Disk model
Hernquist 1990
Halo mass:
Disk density:
Radial dispersion:

9. Spiral arms model m:number of spirals K=C/R:radial wave number
11/16/2018
Spiral arms model
Potential:
Radial verlocity:
m:number of spirals
K=C/R:radial wave number
p:pattern speed
:epicyclic frequency
F:reduction factor

10. 11/16/2018
Parameters
(kpc)

11. 11/16/2018
Disk stars

12. SIM Mission time & the number of targets
11/16/2018
SIM Mission time & the number of targets
240hr
10μas 
N=810

13. Markov Chain Monte Carlo
11/16/2018
Markov Chain Monte Carlo
Likelihood:
n:number density of stars
V:volume ~p-4(p-3)

14. Provability distribution of p
11/16/2018
Provability distribution of p
V~p-3

15. Recovery by MCMC. (N=810)
11/16/2018

16. 11/16/2018
Consistency Check
10 MCMC runs

17. Accuracy v.s. Numer of stars
11/16/2018

18. Accuracy v.s. parallax accuracy
11/16/2018

19. 11/16/2018
Disk stars 

20. Accuracy v.s. 
11/16/2018

21. Summary SIM can constrain Rotation curve in 3% up to 20 kpc δMN-1/2
11/16/2018
Summary
SIM can constrain Rotation curve in 3% up to 20 kpc
δMN-1/2
δM do NOT depnd on δp until 500μas
 should be >60
Knowing the error distribution is important
APOGEE, RVs with <0.5 km/s for 1-2 x 10^5 stars

22. Likelihood surface. (N=810)
11/16/2018
68%,95%CL.

23. 11/16/2018

24. 2005: Satellite Galaxy Tails
11/16/2018
Extensive new data on Sgr tidal streams
2 new wraps of debris (Pakzad et al. 2005)
Evidence for interaction w/LMC 2 Gyrs ago (Majewski, Nidever et al., in prep)
Proper motion predictions for the LMC-Sgr interaction made.
Extensive RV survey of Sgr core (~1500 stars)