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SEGUE Target Selection on-going SEGUE observations

SEGUE Target Selection on-going SEGUE observations. SDSS/SEGUE status as of Nov. 10, 2004 Black= completed stripe or plate pair 1002/3900 sq deg imaging: 25% complete, 34/400 plates 8.5% complete. SEGUE Imaging Aug-Oct 2004: Aug 2004 1260 N 38 sq deg 291 N 104

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SEGUE Target Selection on-going SEGUE observations

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  1. SEGUE Target Selection on-going SEGUE observations

  2. SDSS/SEGUE status as of Nov. 10, 2004 Black= completed stripe or plate pair 1002/3900 sq deg imaging: 25% complete, 34/400 plates 8.5% complete.

  3. SEGUE Imaging Aug-Oct 2004: Aug 2004 1260 N 38 sq deg 291 N 104 Sep 2004 1100 N 105 1260 S 60 1100 S 107 72 S 117 72 N 62 Oct 2004 72 N 55 1300 N 52 1300 S 47 --------------------- 747 sq deg + earlier scans: 255 --------------------- 1002 sq deg 25% of SEGUE goal Drillable imaging (filled Stripes N&S): 1100 N&S 200 sq. 1220 N&S 175 sq. portions of: 72 N&S 200 sq. 1300 N&S 40 sq. Stripes 1100&72 were scanned in Aug/Sep and targetted/drilled for Nov/Dec observing (6 week turnaround)

  4. SEGUE imaging sample Color-Magnitude diagrams in 10 square degree boxes towards one direction on the sky...

  5. Dual turnoffs, indicates stream(s?) at 10 and 20 kpc from the sun. Thick Disk Fs Thin disk M stars Halo or stream(s)? Color-Magnitude (g-r,g) diagram for Strip 1260N

  6. SEGUE spectroscopic sample: Radial Velocities of populations of similar stars, Metalicity, Teff, log g determinations Kinematic, Chemical population studies of the Milky Way and halo

  7. Numbers indicate allocation of fibers by spectral type per plate pair. 25 WD 150 A/BHB 200 F 375 G III +V 150 Low Metals 100 K III 100 K V 30 sdM (and L/T candidates) 10 AGB 10 Cool Wds SEGUE target selection currently has 11 categories, freshly reviewed, and aims to observe a total of 240,000 stars arount the sky. Samples of the stellar categories:

  8. SEGUE spectroscopy to date: Aug 2004: 8 Bright, 8 Faint Sep 2004: 7 Bright, 6 Faint Oct 2004: 3 Bright, 2 Faint --------------------------- 18 B 16 F 34/400 Plates done = 8.5% of SEGUE goal 43.6 plate equivalents To date we have approx. 16,000 classified spectra, grouped in these categories (approximately): 1500 A/BHBs, 3000 F, 6000 G, 150 K giants, 1500 K dwarf, 300 WD, 800 M dwarf, 2500 Low Metal candidates (F-K), plus assorted QSOs and stars of unknown type.

  9. White Dwarf

  10. Cool White Dwarf Candidate

  11. BHB Star, probe outer halo, streams to 150 kpc

  12. F turnoff star, trace streams, halo, low [Fe/H] to 20kpc

  13. G dwarf, largest SEGUE sample, probe disk/inner halo 1.5kpc to 8 kpc distances, Stream Giants also here

  14. -250 -200 -150 -100 -50 0 50 km/s G dwarf Radial Velocity histograms, by Magnitude (dist)

  15. K Giants - probe halo to 200 kpc, total Mass of MW,

  16. K dwarf , kinematics from match to USNO-B, +RV photometric parallax – probe disks from 0.5 – 2 kpc

  17. Lower Metals than the lowest metalicity Globular cluster! Low metalicity candidate, [Fe/H] = -2.6, g=15.8, g-r=0.47 Pop III exploration, gradients in inner/outer halo

  18. M dwarfs, M,L,T dwarf candidates, M sub-dwarf cands sample of halo M dwarfs vs. low-metal F's

  19. AGB candidate, Giants in Sagittarius/Monoceros streams? g = 16.5,g-r =1.12, u-g = 3.1, RV= -72km/s d(AGB) = 18 kpc

  20. K Giant: Narrower lines, features less deep. K dwarf Stronger features, broader lines. How to tell a (distant) K giant from a (nearby) K dwarf, using SDSS/SEGUE spectra.

  21. Using the spectra to separate giants from dwarfs, one can explore halo structure with K giants. Sun SEGUE K giant stars used to probe halo to d> 50 kpc

  22. To test ability to determine metalicity of stars from SDSS/SEGUE spectra, we obtain spectra of objects with known Metals [Fe/H] = -1.6 g +1 0 -1 [Fe/H] -2 -3 g-r Target cluster stars separate well from field stars, with spread of 1 sigma = 0.25 dex. Radial Velocity

  23. With atmospheric parameters determined for stars, one can go from observed 'color-magnitude' diagrams to... g g-r surface gravity Physical Hertzsprung- Russell diagrams: Green: cluster giants Red: Field stars Yellow: Proper motion definite cluster matches Teff

  24. SEGUE is doing well with the grant of Fall season observing during the last full year of SDSS-I. This 2004 data is available to all SDSS participants for analysis and papers.

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