1. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference SOLIS A Long, Careful Look at the Sun Jack Harvey National Solar Observatory

2. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Overview Why What Drivers/design Some data samples Opportunites for German-US collaboration Summary

3. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Why Study the Sun?  Our only vital astronomical object  It’s the astrophysics of here and now  As challenging as any area of astrophysics  Practical applications (space weather, climate)  Often first use of new photonics  AAAS Journal Science posed 125 Big Science questions for its 125 th anniversary issue of July 1, 2005; one was “What drives the solar magnetic cycle?”

4. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference German and US Solar Programs  Long histories of observation and theory  Long history of beneficial collaborations  Both countries now building modern 1.5 m facilities for short-term optical observations  Both interested in advanced photonics  Germany ceased long-term optical (synoptic) programs  US invested in SOLIS synoptic program

5. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference What is SOLIS?  Synoptic Optical Long-term Investigations of the Sun  State-of-the-art instruments designed to measure the Sun regularly for 25 years  Replaces and modernizes successful NSO program started in 1973  SOLIS started regular observations 2003  Science goals aimed at solar activity  Decadal Survey urges a 3-station network

6. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Virtues of SOLIS VSM Regular full-disk vector magnetograms Full Stokes spectral profile information Chromospheric magnetograms High efficiency optical path (6×10 7 ph/pix/s) Low polarization telescope Long projected life (~2028) Open data archive Complements related space projects (e.g., SOHO, TRACE, Hinode, STEREO, Sunrise, SDO, Solar Orbiter, etc.)

7. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Why Long-Term?  Magnetic solar cycle is 22 years  Many solar processes are slow  Synoptic data taken since 1973 still widely used for today’s research and to address originally unforeseen questions  Maximize the scientific payoff for the initial investment

8. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference 48 Solar Rotations

9. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Why Frequent?  Many basic solar processes occur rapidly  Increased chance of capturing rare events  Minimize observational gaps  Smooth out noisy local solar processes  Provide frequently updated boundary conditions for data assimilation modeling  Prompt forecasting of space weather

10. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference SOLIS on Kitt Peak

11. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Long-slit spectropolarimeter 80-cm window, 50 cm aperture Helium filled Single crystal Si secondary Ferroelectric LC modulators High reflectivity coatings All light used Vector SpectroMagnetograph German tip-tilt mount German beamsplitters

12. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference SOLIS VSM 10 4 Dynamic Range 2004 January 6

13. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Field strengthAzimuth in sky planeInclination to line of sight SOLIS VSM Vector Magnetogram

14. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference

15. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference SOLIS VSM – Hinode XRT

16. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference SOLIS Collaboration Opportunities 1.Short-term campaigns  In progress (e.g. Solanki; Wilhelm) 2.Instrumental improvements 3.Long-term associations  Model – Data comparisons  Gregor  ESA Solar Orbiter 4.Partners in building a global SOLIS network

17. June 12, 2007J. Harvey DFG-NSF Astrophysics Research Conference Summary  Long-term study of Sun is vital  Advanced photonics as used in SOLIS enable that research  SOLIS provides unique data waiting to be exploited  SOLIS welcomes collaborations! http://solis.nso.edu