SOME COMMENTS ABOUT THE GIANT CHINESE SOLAR TELESCOPE CONCEPT JACQUES M. BECKERS Beijing August 6 – 8, 2011

OVERVIEW OF RECENTLY BUILD HIGHEST RESOLUTION SOLAR TELESCOPES

DUNN SOLAR TELESCOPE Sacramento Peak NM APERTURE76 cm VACUUM TELESCOPE (FIRST) ADAPTIVE OPTICS

SWEDISH SOLAR TELESCOPE La Palma, Canary Islands APERTURE100 cm VACUUM TELESCOPE ADAPTIVE OPTICS

DUTCH OPEN TELESCOPE (DOT) La PalmaCanary Islands APERTURE 50 cm OPEN AIR TELESCOPE

HINODE JAPANESE + TELESCOPE APERTURE50 cm SPACE FACILITY => No Seeing All Wavelengths

LARGEST AND BEST SOLAR TELESCOPE NOW: BIG BEAR NEW SOLAR TELESCOPE (NST) NST PARAMETERS Diameter1.6 meter Primary f-ratiof/2.4 λ Range μm AOyes MCAO (DCAO)in future NST IS PROTOTYPE FOR ADVANCED TECHNOLOGY SOLAR TELESCOPE

COMPARISON OF HINODE WITH BBSO NST OBSERVATIONS DIAMETER = 0.5 DIAMETER = 1.6-m

LARGEST AND BEST CHINESE SOLAR TELESCOPE NOW: FUXIAN LAKE SOLAR TELESCOPE FUXIAN SOLAR TELESCOPE Diameter1.0 meter Primary f-ratio~ f/.92 λ Range μm AOin future

LARGE SOLAR TELESCOPES FOR THIS DECADE ADVANCED TECHNOLOGY SOLAR TELESCOPE (ATST) HALEAKALA, HAWAII APERTURE4-meter ADAPTIVE OPTICS (later MCAO) EUROPEAN SOLAR TELESCOPE (EST) LA PALMA or TENERIFE APERTURE4-meter MULTI CONJUGATE AO

ADVANCED TECHNOLOGY SOLAR TELESCOPE Completion 2017 INSTRUMENTATION

MAJOR PROGRESS IN SOLAR OBSERVING CAPABILITIES COINCIDES WITH ENORMOUS IMPROVEMENTS IN MAGNETO-HYDRODYNAMIC MODELING CAPABILITIES THEORY  OBSERVING SYNERGY

MATTHIAS REMPEL High Altitude Observatory Boulder CO USA RESOLUTION: 16 x 16 x 12 km = > x arcsec TIME SPAN: 48 hours

OBSERVATION Swedish Solar Telescope MHD MODEL Matthias Rempel INTENSITY IMAGES

MAGNETIC FIELD OUTWARD FLOW

INTENSITY VERTICAL MAGNETIC FIELD BOB STEIN Michigan State University Lansing, MI USA RESOLUTION: 6 km = arcsec

“RAW” (12.1-m) ATST (4-M) NST (1.6-m) SST (1-m) HINODE (0.5-m) G-BAND (431 nm) λ (μm) Nearby Line CaII ▲( 8-m) Δ( 4-m) 3.2-m HeI 12-m ▲ 4.8-m Δ FeXIII FeI (g=3) 16-m ▲ 6.4-m Δ (4-m) 2-m ~ 1.6 H - minimum 3.44 B α (4.05) & Bβ (2.63) ▲ (8-m) Δ( 4-m) 4.80 CO Bands ▲ Δ 6.90 opaque atmosphere ▲(8-m) Δ » 12.3 MgI (3700K) ▲ »

“RAW” (12.1-m) ATST (4-M) NST (1.6-m) SST (1-m) HINODE (0.5-m) G-BAND (431 nm) λ (μm) Nearby Line CaII ▲( 8-m) Δ( 4-m) HeI ▲ Δ FeXIII FeI (g=3) ▲ Δ ~ 1.6 H - minimum 3.44 B α (4.05) & Bβ (2.63) ▲ Δ 4.80 CO Bands ▲ Δ 6.90 opaque atmosphere ▲ Δ » 12.3 MgI (3700K) ▲ »

EFFECT OF MULTI-CONJUGATE ADAPTIVE OPTICS ESO MCAO DEMONSTRATOR * Requires Knowledge of Wavefront Distortion vs Height => Needs Atmospheric Tomography * Uses Multiple Deformable Mirrors Conjugated to Different Heights * Increases Field-Of-View by Factor 2N (diameter) or 4N 2 (N=nr of DMs) * Included in Design of All Extremely Large Nighttime and Solar Telescopes No MCAO With MCAO

CaII 0.86 μm FeI μm CO Bands 4.80 μm MgI 12.3 μm. CORRECTED FIELD-OF-VIEW FOR SINGLE CONJUGATE AO (SCAO) AND TRIPLE CONJUGATE AO (TCAO) NOTES: (1) FOV is not Dependent on Telescope Diameter (2) At 12.3 µm MgI has Full Disk image with 0.3” Resolution!

ATMOSPHERIC TOMOGRAPHY WITH THE RING TELESCOPE

BEAM CROSSECTION Height 12 km λ = 1.56 µm Corrected Area: SCAO (20”) TCAO (100”) 8-meter RING TELESCOPE

BEAM CROSSECTION Height 12 km λ = 1.56 µm Corrected Area: SCAO (20”) TCAO (100”) 8-meter FILLED TELESCOPE

RING TELESCOPES REQUIRES MORE (~ 3 x) “GUIDE STARS” (= sub-areas on Sun) THAN FILLED-APERTURE TELESCOPES

CONCLUSIONS FOR 8-METER APERTURE CHINESE GIANT SOLAR TELESCOPE DESIGN 1. Design Telescope for Near-Infrared & Infrared Wavelengths (0.8 μm – 13 μm) 2. Note that in IR Sunspots are Less Dark and Hence Less Affected by Scattered Light 3. Allow for Future Extension to Visible Wavelengths in case MHD Models & ATST/EST Data Demand Better Resolution 4. Include Multi-Conjugate Adaptive Optics (MCAO => TCAO?) 5. Prefer Filled Aperture to Allow for Atmospheric Tomography 6. But Ring Aperture Ok but will Requires ~3x more “Guide Stars” 7. Consider Low Scattered Light at IR Wavelengths (Coronagraph) to Allow Coronal Magnetic Field Observations at High Resolution 8. Consider also Laser Guide Star SCAO or TCAO in Corona

WHAT ABOUT LOCATION ?? I MONGOLIA !

TOLBO NUUR MONGOLIA 50 km S of ÖLGII 2080 m ALTITUDE 3 x 20 km SIZE FRESH WATER

TOLBO NUUR 2080 m HIGH 3 x 20 km URUMQI

Figure 7. Daily mean distribution per month of probable NAOH (number of astronomical observation hours) for three Mongolian sites and for two sites in Middle Asia. Circles: Khureltogot, +:Dalanzadgad, ×: Muren,squares: Khairabad, triangles: Sanglock.Figure reference:[1]. References [1] Batsukh G, Ganbaatar D, Khaltar D and Tugjisuren N 1995, A&ASS NIGHTTIME! HOURS!

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