Josh Winn

2. Models for the Eclipsesof the T Tauri Star KH 15D:Occultation Mapping of a Pre-Main-Sequence Star Josh Winn Harvard-Smithsonian Center for Astrophysics In collaboration with: Matt Holman, Kris Stanek, and Dimitar Sasselov (CfA), John Johnson and Geoff Marcy (U.C. Berkeley), Catrina Hamilton (Mt. Holyoke), Bill Herbst (Wesleyan)

3. The Case of theMysterious Winking Star Josh Winn Harvard-Smithsonian Center for Astrophysics In collaboration with: Matt Holman, Kris Stanek, and Dimitar Sasselov (CfA), John Johnson and Geoff Marcy (U.C. Berkeley), Catrina Hamilton (Mt. Holyoke), Bill Herbst (Wesleyan)

4. T.A. Rector and B.A. Wolpa (NRAO/AUI/NSF and NOAO/AURA/NSF)

6. Spectral energy distribution of TW Hya Disk Photosphere Calvet et al. (2002)

9. T.A. Rector and B.A. Wolpa (NRAO/AUI/NSF and NOAO/AURA/NSF)

10. T.A. Rector and B.A. Wolpa (NRAO/AUI/NSF and NOAO/AURA/NSF)

13. Rotation periods of pre-main-sequence stars Lamm et al. (2003)

14. The unusual star 15D Kearns & Herbst (1998)

15. The unusual star 15D Kearns & Herbst (1998)

16. The unusual star 15D Kearns & Herbst (1998)

17. The unusual star 15D Kearns & Herbst (1998)

18. The unusual star 15D Kearns & Herbst (1998)

19. The unusual star 15D Kearns & Herbst (1998)

20. The unusual star 15D Kearns & Herbst (1998)

21. Eclipses by circumstellar dust Kearns & Herbst (1998), Hamilton et al. (2001)

22. Hamilton et al., in preparation

23. Hamilton et al., in preparation

24. Density waves in aprotoplanetary disk (2-d simulation by G. Bryden)

25. Observations of KH 15D VLT, Subaru, Hobby-Eberly, MMT, Magellan, Gemini, Keck, HST, Chandra, Spitzer…

26. Observations of KH 15D VLT, Subaru, Hobby-Eberly, MMT, Magellan, Gemini, Keck, HST, Chandra, Spitzer… Harvard College Observatory plate stacks (1913-1951)

27. Observations of KH 15D VLT, Subaru, Hobby-Eberly, MMT, Magellan, Gemini, Keck, HST, Chandra, Spitzer… Harvard College Observatory plate stacks (1913-1951) The Astrophysical Observatory of Asiago (1967-1981)

28. Archival observations of KH 15D Johnson & Winn (2004)

29. Archival observations of KH 15D Johnson & Winn (2004)

30. Archival observations of KH 15D • The bright state was >2 times brighter Johnson & Winn (2004)

31. Archival observations of KH 15D • The bright state was >2 times brighter • The fractional variations were only 54% instead of 95% Johnson & Winn (2004)

32. Archival observations of KH 15D • The bright state was >2 times brighter • The fractional variations were only 54% instead of 95% • The phase of minimum light was shifted by ≈180° Johnson & Winn (2004)

33. Archival observations of KH 15D There is a second star in the system, which is presently obscured. Johnson & Winn (2004)

34. Archival observations of KH 15D • Where did the second star go? Johnson & Winn (2004)

35. Archival observations of KH 15D • Where did the second star go? • Why is there little or no radial velocity variation? Johnson & Winn (2004)

36. Archival observations of KH 15D • Where did the second star go? • Why is there little or no radial velocity variation? • Why was there a phase shift? Johnson & Winn (2004)

37. Archival observations of KH 15D What causes the eclipses and their evolution? Johnson & Winn (2004)

38. B A

39. 1950 B A

40. Flux 1950 B A Time

41. Flux 1970 A Time

42. Flux 1980 A Time

43. Flux 2000 A Time

44. Flux 2004 A Time

45. Flux 1995 A Time

46. KH 15D: gradual occultation of a pre-main-sequence binary Winn et al. (2004) Flux 1995 A Time

47. KH 15D: gradual occultation of a pre-main-sequence binary Winn et al. (2004)

48. KH 15D: gradual occultation of a pre-main-sequence binary Winn et al. (2004)

49. KH 15D: gradual occultation of a pre-main-sequence binary Winn et al. (2004)

50. KH 15D: a spectroscopic binary Johnson et al. (2004)