1. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Gábor F ű rész, predoc fellow Harvard-Smithsonian Center for Astrophysics Application of Hectochelle: Dynamical Studies of Open Clusters

2. Application of Hectochelle - MMT Science Symposium, 06/14/2006Gábor Fűrész - Application of Hectochelle; 06/14/2006, Tucson Talk outline Talk overview Brief description of the Hectochelle Some scientific programs underway with Hectochelle: NGC 2264 – signs of cluster formation Orion Nebula Cluster – birth of a cluster NGC 1907 & 1912 – interacting open clusters Plans for the future

3. Application of Hectochelle - MMT Science Symposium, 06/14/2006 The Hectochelle Team PI: A.Szentgyorgyi Detectors:J.Geary, B.McLeod, S.Amato Optical Design:D.Fabricant, H.Epps Operational Support:N.Caldwell, G.Williams Software:M.Conroy, J.Roll Mech Eng:R.Eng, J.Barberis, M.Honsa, P.Cheimets Struct Eng: H.Bergner, R.Fata, M.Pieri Elec Eng: T.Gauron, D.Weaver Fibers/Calibration: J.Zajac Tech Support: F.Collette, W.Brymer, F.Rivera, R.Goddard, S.Nichols Management: L.Feldman, C.Osterer, T.Norton, P.Sozanski Science Team: L.Hartmann, D.Latham, A. Dupree, S.Korzennik, P.Nisenson, R.Noyes, S.Baliunis MMT Staff “Deputy.PI”: G.Fűrész

4. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Hectochelle Performance Parameters A multiobject high resolution (echelle) spectrograph for the post-conversion MMT, operating at f/5 - Resolution: 34,000 - Single order - Order separation by filter - Number of fibers: 240 - Shares HectoRobot as Hectospec - Number of available passbands, typically 150Å wide - Typical efficiency: 8% - Precision radial velocity (PRV) in development

5. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Fiber positioner

6. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Fiber positioner Fred and Ginger Twin gantry geometry Each robot  5 axes (x,y,z, ,  )

7. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Positions 300 optical fibers on curved 1º focal plane in 5 minutes with < 25µ accuracy. Fibers magnetically attached to focal surface. Positioner consists of two robots operating simultaneously. Plate scale is 174μ/arcsec Fibers are 250µ dia. (1.4 arcsec) Fiber positioner

8. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Hectospec (left) and Hectochelle (right) in early phase of integration at the MMT. The Hectochelle is instrumented with a test fiber slit. Bench spectrographs: Hectospec and Hectochelle

9. Application of Hectochelle - MMT Science Symposium, 06/14/2006 20 Minute exposure of Kepler field Color and pincushion present Slit tilt present Sample data

10. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Performance RMS: 56 m/s RMS: 225 m/s

11. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Examples of Science Programs In Progress Surveys of Young Clusters - Hartmann, Calvet et al. Kepler Ground Segment – Latham, et.al. Internal Dynamics of Local Group dSphe – Olszewski, Mateo et al. & Majewski et al. PRV Extrasolar Planet Searches – Korzennik, Noyes, Latham, &c. Wisconsin Open Cluster Survey (WOCS) – Mathieu, Latham, et al. Studies of Globular Cluster Spitzer Sources – Dupree, et al. Absorption line distance to the Cygnus Loop – Eriksen Chromospheric Activity of Solar-Type Stars - Baliunis et al. Open Cluster Dynamics – Fűrész & Hartmann, et al.

12. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: NGC 2264 targets based on a list of X-ray sources (Ramírez et al. 2004) and later 2MASS sources added (selected in color-color diagram)

13. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: NGC 2264 Radial velocity distribution - distribution is not gaussian -  ~ 3.5 km s-1

14. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: NGC 2264 Radial velocity vs. spatial distribution - matching molecular gas key: Hectochelle targets in a given RV bin Ha emission stars form Reipurth et al. 2004 13CO channel maps from Ridge et al. 2003

15. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: NGC 2264 Radial velocity vs. spatial distribution

16. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Model simulation: Finite sheet evolution with gravity, initially elliptical, uniform  :  then forms filament with higher concentrations of mass at ends!  pileup of material at edge, PLUS focal points at ends! Finite sheet evolution with gravity

17. Application of Hectochelle - MMT Science Symposium, 06/14/2006 velocity dispersion Finite sheet evolution with gravity: rotating ellipse

18. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Finite sheet evolution with gravity – NGC 2264 (GM/R (r/R)) 1/2 ~ (G [4000 M  ]/3.5 pc (0.55)) 1/2 ~ 1.6 km/s faster infall at ends - focal point behavior

19. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: ONC

20. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Finite sheet evolution with gravity – ONC Orion A Orion B

21. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Finite sheet evolution with gravity – ONC Orion A has a similar structure (clumps along a filament) as the Burkert- Hartmann theory predicts

22. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Hectochelle field of view is shown in cyan. Likely cluster members based on RV: Green – errors less than 1 km/s Red- errors greater than 1 km/s Blue- Observed on both nights Size of dots is proportional to quality of radial velocity: larger dot-better velocity fit IRAC image of the ONC with cluster members Open cluster kinematics: ONC

23. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: ONC Histogram of cluster members: Average radial velocity is 26.6 km/s Velocity dispersion ~ 4 km/s

24. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: ONC

25. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: ONC

26. Application of Hectochelle - MMT Science Symposium, 06/14/2006 ONC: triggered star formation?

27. Application of Hectochelle - MMT Science Symposium, 06/14/2006 NGC 1907 & 1912 age ~250 Myr distance ~1300 pc separation ~18 pc supposed pair (Subramaniam & Sagar, 1999) photometry: FLWO 48” and MiniCam target selection for Hectochelle spectroscopy, based on CMD Open cluster kinematics: M 38

28. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: M 38 Photometric result: average color inbetween the clusters is closer to the value of clusters, rather than field stars: hint for a tidal bridge? also, signs for tidal tails

29. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: M 38

30. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: M 38 Region C (NGC 1912) total/member106/45 mean RV -0.9 ( 0.7) km/s dispersion3.8 km/s Region B (bridge) total/member57/28 mean RV -0.7 ( 1.1) km/s dispersion3.6 km/s Region A (NGC 1907) total/member35/10 mean RV -3.3 ( 1.1) km/s dispersion4.5 km/s

31. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: M 38 N body simulation using STARLAB: fly-by of two clusters,  V=3 km/s

32. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Open cluster kinematics: M 38  1 = 3 km/s  2 = 3 km/s

33. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Histogram of stars from our sample which have ages from Hillenbrand (1997). Ages were determined by evolutionary track fitting. What is the dispersion of so-called old and young stars from our sample? Future Plans

34. Application of Hectochelle - MMT Science Symposium, 06/14/2006 Empty Regions Why are these here? If all off- cloud stars are ONC members, there should be a continuous flow of stars, as in Trapezium region (yellow rectangle). Possible explanation is the off-cloud stars are part of another, older association: Orion OB1c To answer this, age determination is necessary for more stars. Future Plans: age determination

35. Application of Hectochelle - MMT Science Symposium, 06/14/2006 hectochelle@cfa.harvard.ed u