CCD Observations and Preliminary Analysis of the “End-of-the-Line” W UMa Eclipsing Binary V523 Cas

1. CCD Observations and Preliminary Analysis of the “End-of-the-Line” W UMa Eclipsing Binary V523 Cas Presenting Authors: Russell M. Genet, Orion Observatory Thomas C. Smith, Dark Ridge Observatory Contributing Authors: Dirk Terrell, Southwest Research Institute Laurance Doyle, SETI Institute

2. First year “pilot” • Concentrated on two W UMa binaries • Complete light curves every night • Often from two observatories • Primary science goal • Study changes in light curve shapes • Secondary science goals • Precise seasonal ephemeredes • Consider hot “Jupiter” transits • Technical goals • Develop analytical tools • Explore photometric precision Program Overview

3. Presentation Outline • Introduction to W UMa Binaries • Observations and Reduction • V523 Cas Preliminary Analysis • V523 Cas “Movie” • Question & Answers Russ Tom Russ Tom All

4. Presentation Outline • Introduction to W UMa Binaries • Observations and Reduction • V523 Cas Preliminary Analysis • V523 Cas “Movie” • Question & Answers Russ Tom Russ Tom All

5. Introduction to W UMa Binaries • Photometric / Magnetic Variability • Intrinsic Period Changes • Third – Body Period Changes • Planetary Transits

6. Introduction to W UMa Binaries • Photometric / Magnetic Variability • Intrinsic Period Changes • Third – Body Period Changes • Planetary Transits

7. Over contact • Dissimilar stars W UMa’s Binaries Common envelope • Very Different masses Yet nearly same temperature • Huge transfer of energy Large to small

8. Color – Period Relationship

9. Color – Period Relationship

10. A and W TypeW-UMa Binaries A W More evolved Higher masses Thicker envelopes Unevolved Lower masses Cannot achieve equilibrium Period changes Light curve variability Brighter star Dimmer star

11. Large Rosby number • Fast rotators • Long convection turnover times • For single stars Late Slow rotator • For W UMa Late Fast rotator • Ideal “laboratories” for magnetic activity • Revealed through changing light curves • “Movies” instead of disjointed snapshots W Type W UMa Variability

12. Bright Northern Short Period W UMa’s

13. Introduction to W UMa Binaries • Photometric / Magnetic Variability • Intrinsic Period Changes • Third – Body Period Changes • Planetary Transits

14. Intrinsic Period Changes • Angular Momentum Loss • Gravitational radiation • Mass loss • Magnetic breaking • Mass transfer between stars • Applegate effect

15. Introduction to W UMa Binaries • Photometric / Magnetic Variability • Intrinsic Period Changes • Third – Body Period Changes • Planetary Transits

16. SETI Visit with Laurance Doyle

17. Barycenters

18. V523 Cas Long-Term O-C

19. CM Dra Program

20. Introduction to W UMa Binaries • Photometric / Magnetic Variability • Intrinsic Period Changes • Third – Body Period Changes • Planetary Transits

21. Transit Perspective II I Inclination Angle

22. High Inclination W UMa Stars

23. Solar Radii vs. Line-of-Sight Inclination Angle

24. Three Transit Plots

25. Presentation Outline • Introduction to W UMa Binaries • Observations and Reduction • V523 Cas Preliminary Analysis • V523 Cas “Movie” • Question & Answers Russ Tom Russ Tom All

26. Dark Ridge Observatory (DRO)

27. Orion Observatory (OO)

28. Image Reduction Flowchart

29. DRO/OO Observational Database 2004

30. Light-Curve Database

31. Raw Text File to Raw Excel 25K 1 Sub buildPhase() ' use the getPhase function to populate the phase field Dim myDb As Database Dim myRs As Recordset Set myDb = CurrentDb() Set myRs = myDb.OpenRecordset("Select * from tblLightCurve", dbOpenDynaset) Do While Not myRs.EOF myRs.Edit myRs.Fields("Phase").Value = getPhase(myRs.Fields("HJD").Value).phase myRs.Fields("Cycle").Value = getPhase(myRs.Fields("HJD").Value).Cycle myRs.Update myRs.MoveNext Loop MsgBox "Done" End Sub Sub buildAdjustedPhase() ' use the getPhase function to populate the phase field Dim myDb As Database 2 1a 3 Raw Source Database

32. Presentation Outline • Introduction to W UMa Binaries • Observations and Reduction • V523 Cas Preliminary Analysis • V523 Cas “Movie” • Question & Answers Russ Tom Russ Tom All

33. V523 Cas Preliminary Analysis

34. Specialized analysis • Complete light curves only • Many complete curves • Multiple observatories • Preliminary • Analysis not completed • No ensemble photometry yet • Automation • Not just labor efficiency • Parametric outer loop • In conjunction with WD (Terrell) Analysis Considerations

35. Edits and Adjustments

36. Edits and Adjustments

37. Beginning and Ending Database Rows

38. Typical DRO 21K Database Light Curve

39. Typical OO 21K Database Light Curve

40. Classical Analysis

41. Robert Nelson’s Minima23

42. V523 Cas Seasonal O-C

43. Phase-Binned Analysis

44. Eclipsing Binary Phases 0.00 0.25 0.50 0.75 0.00 0.25

45. { } HJD to Phase Transformation Φ Epoch – JD Obs Period = Epoch = 2453234.63551606 Period = 0.23369537

46. 21K Data Point Phase Plot V523 Cas

47. Phase Binning { } Φ Epoch – JD Obs Period =

48. ... Phase – Binned Analysis I

49. ... Phase – Binned Analysis II Difference Engine ...

50. V523 Cas 2004 Season Master Curve Utilizing the Binning Method