WAVEFRONT CHARACTERIZATION CAMPAIGN AT PARANAL

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1 WAVEFRONT CHARACTERIZATION CAMPAIGN AT PARANAL DECEMBER Marc Sarazin, Gianluca Lombardi, Julio Navarrete; ESO -Aziz Ziad, Amokrane Berdja, Julien Borgnino, Wassila Dali Ali, Jérôme Maire; LUAN-UMR UMR Université de Nice -Andrei Tokovinin, i Edison Bustos, CTIO -Héctor Vázquez Ramió, Marcos Reyes, José Miguel Delgado, Jesús J. Fuensalida; Instituto de Astrofísica de Canarias 1 FOR ROT-Sardenia Septemb ber 2008

2 WAVEFRONT CHARACTERIZATION CAMPAIGN AT PARANAL DECEMBER 2007 Using DIMM-MASS-GSM-MOSP-LuSci & SCIDAR 2 ESO/LUAN/IAC/CTIO Joint effort FOR ROT-Sardenia Septemb ber 2008

3 THE GOALS OF THE CAMPAIGN ELT-DS (EU-FP6) funds Understand the properties of the optical turbulence at ELT scales (which model for L0?) Understand the transition from free air to telescope enclosure Cross-correlate various instruments used in site surveys, establish confidence levels FOROT T-Sardenia September

4 Spatial scales at which turbulence is probed by different instruments Kolmogorov / von Kàrmàn von Kàrmàn?? GSM MOSP SCIDAR LUSCI MASS DIMM AO WFS: NACO Interferometry: AMBER Nice & ESO ESO & ONERA ESO 2m 8m FOROT T-Sardenia September 2008 Instruments baselines or diameters 4

5 MASS-DIMM (C N2 (h), ε 0, τ 0 ) LUSCI (C N2 (h)) SCIDAR (C 2 N2 (h),v(h), ε 0, θ 0, τ 0 ) MOSP (L 0 (h), C N2 (h), ε 0 ) DIMM (ε 0, τ 0 ) GSM (ε 0, L 0, θ 0, τ 0 ) NACO (ε 0, L 0, τ 0 ) AMBER (OPD, ε 0, L 0 ) CN2 : structure constant L0 : outer scale V : wind speed ε 0 : seeing θ 0 : isoplanatic angle τ 0 : coherence time 5 FOROT T-Sardenia September 2008

6 C CORRECTION FROM GROUND (6M) TO ELT (50-100M) 6 a March Slide seeing, Kon Symposium on s Seeing conditions are monitored at lower height above ground Direct measurement of the surface layer turbulence properties in the first 100m? Indirect estimations: UT-DIMM comparison MASS-DIMM comparison SLODAR-MASS-DIMM comparison LuSci-MASS-DIMM-GSM comparison 6m 30m DIMM UT ELT m

7 WHERE? Cute-SCIDAR location at Paranal N E The Paranal Astronomical Site Monitor is located on the platform, in a zone diametrically opposite to the Control Building, just behind the VST. The CUTE-SCIDAR@AT4 is located on the platform, in VLTI J2 Station. FOROT T-Sardenia September

8 Cute-SCIDAR at Paranal (AT4 focus) for E-ELT Site Characterisation (Vázquez Ramió et al; The Messenger 132 June 2008) INSTRUMENT COMMISSIONED IN NOVEMBER 2007 Data collected during 20 nights between November and December 2007 December acquisitions included in the Navidad Campaign 8

9 Meteo, DIMM, GSM and MOSP, MASS and LuSci 9

10 DIMM, GSM and MOSP SCIDAR

11 11 Synchronous acquisitions

12 GSM and MOSP (Borgnino & al, this conference) & nearby buildings 12

13 LUSCI - J. Beckers, 1993 & this conference - P. Hickson, 2004 & this conference - A. Tokovinin SPIE 7013,

14 14 MASS-DIMM on C11 tube and ASTELCO mount

15 TURBULENCE PROFILES FROM MASS FOROT-Sardenia 15-1 The altitude weighting functions of MASS and SCIDAR are of different physical nature 15 8 September 2008

16 on VLTI J2 Station 300 m vertical resolution layers sensed between the ground (pupil) and 22.5 km above pupil (about 78 layers sensed each 25 seconds) C n2 for each layer (GL + FA) Isoplanatic Angle FOROT T-Sardenia September

17 SCIDAR SCIDAR real time analysis and first post-processingprocessing Real time turbulence evolution including and excluding dome turbulence (see Fuensalida et al. 2008, MNRAS, 389, 731) FOROT T-Sardenia September

18 18 RESULTS

19 19 RESULTS

20 20 RESULTS

21 21 RESULTS

22 22 RESULTS

23 23 RESULTS

24 24 RESULTS

25 25 RESULTS

26 X-Comparison MASS vs Cute-SCIDAR MASS-like structure: 300 m vertical resolution layers sensed between the ground (pupil) and 22.5 km above pupil (about 78 layers sensed each 25 seconds) C n2 for each layer (GL + FA) Isoplanatic Angle FOROT T-Sardenia September

27 X-Comparison MASS vs Cute-SCIDAR MASS-like structure: 27

28 X-Comparison MASS vs Cute-SCIDAR MASS-like structure: clocks from the two instruments are synchronized within few seconds data are 1 minute averages in one night FOROT T-Sardenia September 2008 Cute-SCIDAR averages are synchronized no more than ± 30 sec with respect to MASS data Data reduction continuing 28 Data reduction continuing, more work needed!!!