1. Culmination of the Southern Proper Motion Program T. Girard (Yale University) William van AltenaArnold KlemolaTing-Gao Yang Carlos LópezDana Casetti-DinescuJohn Lee Imants PlataisRené MéndezWen-Zhang Ma Vera-Kozhurina PlataisReed Meyer Dave Monet David HerreraDanilo CastilloNorbert Zacharias Kathy VieiraJin-Fuw Lee

2. T. GirardStars In Motion - Sept 20082 A Brief History of the SPM Program SPM is the southern extension of the Lick NPM program (Klemola 1986). Both are based on W. H. Wright’s (1950) proposal of using external galaxies as a fixed reference frame for proper-motion determination. SPM began, formally, in 1952 as a joint project of Yale and Columbia Univ. El Leoncito, Argentina was selected as the site for the new observatory. Eventually, Columbia was out and Univ. of San Juan, Argentina was in. Observations with the 20-inch double astrograph began July 1 st, 1965 when SPM field #512 (α=19h, δ= -30 °) was successfully taken by Arnold Klemola. The first epoch was essentially completed by the end of 1973. Sky coverage is south of δ= -20 °, with some more northerly fields providing overlap with the Lick NPM.

3. T. GirardStars In Motion - Sept 20083 A Brief History of the SPM Program (cont.) Second-epoch photographic observations from 1988 to 1998, then the supply of Kodak 103 emulsion plates ran out, with ~1/3 of survey repeated CCD cameras installed in 2000 - main astrometry camera, 4Kx4K PixelVision (yellow) - smaller 1Kx1K Apogee 8, replaced by 2Kx2K Apogee Alta (blue) - two auxiliary SBIG ST5c cameras for focusing Second-epoch CCD observations from 2003 - present

4. T. GirardStars In Motion - Sept 20084 Cesco Obs: El Leoncito, Argentina altitude = 2400 m Astrograph: twin 51-cm, f/7 scale = 55.1 “/mm YSO Double-Astrograph at Cesco Obs.

5. T. GirardStars In Motion - Sept 20085 Current SPM Observing Status * * through June 2008

6. T. GirardStars In Motion - Sept 20086 SPM Catalogs The SPM1 and SPM2 Catalogs were based on PDS measures and thus contain only a small fraction of stars down to the plate limit. The SPM3 is based on full plate scans of the SPM plates using the PMM of USNO-FS. SPM1 (1998) SPM2 (1999) SPM3 (2004) (SPM4) (200?) measurementsPDS PMMPMM+CCD sky coverage720 sq deg3,700 sq deg 13,600 sq deg # of objects0.059 M0.322 M10.7 M~ 100 M

7. T. GirardStars In Motion - Sept 20087 Magnitude-Equation Correction SPM (and NPM) plates use objective gratings, producing diffraction image pairs which can be compared to the central-order image to deduce the form of the magnitude equation. A comparison of proper motions derived from uncorrected SPM blue-plate pairs and yellow-plate pairs indicates a significant magnitude equation is present. Using the grating images to correct each plate’s individual magnitude equation, the resulting proper motions are largely free of bias.

8. T. GirardStars In Motion - Sept 20088 SPM Catalog Estimated Uncertainties SPM2 (pds measures) SPM3 (pmm measures)

9. T. GirardStars In Motion - Sept 20089 Harvesting the SPM López & Girard 1990 (PASP 102, 1018) “Accurate Positions for Variable and Suspected Variable Stars South of -67 Deg” Demartino et al. 1996 (IBVS 4321/4322) “Accurate Positions of Variable/Suspected Variable Stars near the South Galactic Pole” Bailyn et al. 2002 (Nature 37, 701) “The Optical Counterpart of the Superluminal Source GRO J1655-40”

10. T. GirardStars In Motion - Sept 200810 Harvesting the SPM Girard et al. 1988 (AJ 95, 58) “Astrometry of SN1987A and SK-69.202°”

11. T. GirardStars In Motion - Sept 200811 Harvesting the SPM Platais et al. 1998 (A&A 331, 1119) “The Hipparcos Proper Motion Link to the Extragalactic Reference System using SPM and NPM”

12. T. GirardStars In Motion - Sept 200812 Harvesting the SPM Carraro et al. 2005 (A&A 433, 143) “Probing the Nature of Possible Open Cluster Remnants with the Southern Proper Motion Program” Dinescu et al. 2007 (AJ 134, 195) “Space Velocities of Southern Globular Clusters V: A Low Galactic-Latitude Sample” Dinescu et al. 2005 (ApJ 618L, 25) “Absolute Proper Motion of the Sagittarius Dwarf Galaxy and the Outer Regions of the Milky Way Bulge” “To date, 53 of ~150 GGC have measured absolute proper motions, with formal errors between 0.1 and 2.0 mas/yr; mean value ~ 0.5 mas/yr. Of those measured, 33 have a single determination, and 25 were measured by the Southern Proper-Motion Program (SPM).”

13. T. GirardStars In Motion - Sept 200813 Velocity Shear of the Thick Disk using SPM3 Girard et al. 2006 (AJ 132, 1768) ◄ SPM3 stars within 15° of SGP  ’s measure transverse motion ► 2MASS photometry to select preferentially thick-disk giants ► N giants ~ 1200

14. T. GirardStars In Motion - Sept 200814 Velocity Shear of the Thick Disk using SPM3 Proper-motion data: Thick-disk component shows up well, distinct from the faint, nearby dwarfs that show a much larger  dispersion. ↓ Transverse Velocities Assume an absolute magnitude distribution as a function of J-K color to convert J,K,  to U,V,d. (Integrate under the assumed magnitude distributions.)

15. T. GirardStars In Motion - Sept 200815 Velocity Shear of the Thick Disk using SPM3 (Somewhat equivalent to separation using reduced proper motion.) ◄ Trim conservatively in U,V to eliminate nearby dwarfs.

16. T. GirardStars In Motion - Sept 200816 Velocity Shear of the Thick Disk using SPM3 Density and Velocity profiles: Over the range 1 < z < 4 kpc the observed sample shows an exponential form in number density and roughly linear forms of mean velocity and velocity dispersion as a function of z. BUT we must correct for systematic biases; (Malmquist and “Lutz-Kelker”-type). ►Use knowledge of our  uncertainties and selection criteria to construct Monte-Carlo simulations and derive the intrinsic Thick-disk parameters: h z = 783 ±48 pc dV/dz = -30 ±3 km/s/kpc d  V,U /dz = 9 ±3 km/s/kpc (and 8 ±6 % halo contamination). [ Figure Key: U-profiles in black, V in gray ]

17. T. GirardStars In Motion - Sept 200817 Ongoing and Future SPM Projects Vieira, K. 2009, Ph.D. Thesis: “Proper-Motion Study of the Magellanic Clouds Using SPM Data”

18. T. GirardStars In Motion - Sept 200818 Ongoing and Future SPM Projects SPM “TBD” –absolute  of Sgr dSph stars along trailing and leading orbital tails –absolute  of CMa overdensity over an extended area –absolute  for 15 globular clusters for which CCD observations exist –absolute  for 19 more globular clusters, CCD obs are still needed –full 3-d velocity distribution of SGP thick-disk giant sample –full 3-d velocity analysis using SPM4/RAVE cross-section