1. Slide 1 (of 18) Circumstellar Disk Studies with the EVLA Carl Melis UCLA/LLNL In collaboration with: Gaspard Duchêne, Holly Maness, Patrick Palmer, and Marshall Perrin NASA/CXC/M.Weiss

2. Slide 2 (of 18) Why study disks?  Star Formation Disk material feeds young star through accretion. Disks facilitate the removal of stellar angular momentum. Jets launched by accreting disk material can impact star’s natal environment. HH30/HST-WFPC2

3. Slide 3 (of 18) Why study disks?  Planet Formation and Evolution Disk grains grow from interstellar size to planetesimals and eventually planets. Disks are the end result of planet and planetsimal collisions. Disk material traces planets through their interaction with grains.  -Pic/HST-STIS

4. Slide 4 (of 18) VLA Protoplanetary Disk Studies Most aimed towards measuring grain growth through spectral indices. Herbig Ae/Be stars: Natta et al. (2004)

5. Slide 5 (of 18) VLA Protoplanetary Disk Studies Most aimed towards measuring grain growth through spectral indices. Rodmann et al. (2006) showed growth to cm sizes and that 7 mm emission is optically thin.  = 0.7±0.1  = 1.3±0.1

6. Slide 6 (of 18) VLA Protoplanetary Disk Studies  = 0.7±0.1  = 1.3±0.1 Greaves et al. may have detected a proto-gas giant planet forming in the disk of HL Tau with high angular resolution 7 mm observations using VLA+PT. Jet Planet?

7. Slide 7 (of 18) VLA Protoplanetary Disk Studies Wilner et al. show growth beyond cm sizes in the disk of TW Hya.  = 0.7±0.1  = 1.3±0.1 Wilner et al. (2005) Wilner et al. (2000) Hughes et al. (2007)

8. Slide 8 (of 18) The EVLA  = 0.7±0.1  = 1.3±0.1 Point source sensitivity for 12 hours on-source, 1  rms.

9. Slide 9 (of 18) The EVLA  = 0.7±0.1  = 1.3±0.1 Q- and K-band receivers with 2 GHz bandwidth will be the first fully available!

10. Slide 10 (of 18) EVLA Disks  = 0.7±0.1  = 1.3±0.1  Protoplanetary Disks Grain growth in a statistical sense as a function of time.  Complete samples of targets for a range of masses.  Several star forming regions, e.g.: Taurus Orion CrA  Oph

11. Slide 11 (of 18) EVLA Disks  = 0.7±0.1  = 1.3±0.1  Protoplanetary Disks Probing the spatial distribution of large grains.  Large grains predicted to drift into host star on short timescales.  Incompatible with current observations!  Need to probe radial distribution of large grains. Johansen & Klahr (2005) Brauer et al. (2007)

12. Slide 12 (of 18) EVLA Disks  = 0.7±0.1  = 1.3±0.1  Protoplanetary Disks Probing the spatial distribution of large grains.  Grain growth and sedimentation are predicted to be intimately linked.  Observe edge-on disks with compact and extended array configurations to test this prediction.

13. Slide 13 (of 18) EVLA Disks  = 0.7±0.1  = 1.3±0.1  Protoplanetary Disks Molecules with EVLA spectral line studies.  Important opacity sources for giant planet atmospheres.  Materials necessary for life. slide courtesy Claire Chandler

14. Slide 14 (of 18) EVLA Disks  Debris Disks A new way to discover planets? HD 107146; Corder et al. (2009) Vega; Wilner et al. (2002) HD 32297; Maness et al. (2008)  BiggerSmaller  >~7 mm~3 mm ~0.1  m ~10  m Watch the pattern move!  Planet at 100 AU orbiting a 10 pc distant 2 M  star moves ~100 mas in 1 year. Wyatt (2005)

15. Slide 15 (of 18) EVLA Disks  Phoenix Giant Disks A second chance for planets? H  in TYC 4144 329 2; Melis et al. (2009) CO (3-2) in BP Psc; Zuckerman et al. (2008)

16. Slide 16 (of 18) The EVLA-ALMA Strip: Star Formation

17. Slide 17 (of 18) The EVLA-ALMA Strip: Disks

18. Slide 18 (of 18) NASA/JPL/CalTech Conclusions  The EVLA will enable unprecedented studies of disks forming and interacting with planets.  Grain growth and sedimentation across the Hayashi tracks.  Protoplanets within disks.  Molecular gas and organic material in disks.  Planets perturbing debris in mature planetary systems.  Rebirth of planetary systems around Phoenix Giants.