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Wavefront Characterization Campaign at Paranal December 2007. ESO/LUAN/IAC/CTIO Joint effort. Using DIMM-MASS-GSM-MOSP- LuSci & SCIDAR. The goals of the campaign. ELT-DS (EU-FP6) funds Understand the properties of the optical turbulence at ELT scales (which model for L0?)
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Wavefront Characterization Campaign at ParanalDecember 2007 FOROT-Sardenia 15-18 September 2008 ESO/LUAN/IAC/CTIO Joint effort Using DIMM-MASS-GSM-MOSP-LuSci & SCIDAR
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-Sardenia 15-18 September 2008
Spatial scales at which turbulence is probed by different instruments Kolmogorov / von Kàrmàn von Kàrmàn?? GSM MOSP SCIDAR LUSCI MASS DIMM Interferometry: AMBER AO WFS: NACO FOROT-Sardenia 15-18 September 2008 ESO Nice & ESO ESO & ONERA 2m 8m Instruments’ baselines or diameters
Instruments and expectedparameters MASS-DIMM (CN2(h),e0, t0) LUSCI (CN2(h)) SCIDAR (CN2(h),v(h),e0, q0, t0) MOSP (L0(h), CN2(h),e0) DIMM (e0, t0) GSM (e0, L0, q0, t0) NACO (e0, L0, t0) AMBER (OPD, e0, L0) FOROT-Sardenia 15-18 September 2008 CN2 : structure constant L0 : outer scale V : wind speed ε0 : seeing θ0 : isoplanatic angle τ0 : coherence time
? 30m 6m DIMM UT ELT Correction from ground (6m) to ELT (50-100m) • 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 50-100m
WHERE? Cute-SCIDAR location at Paranal N The Paranal Astronomical Site Monitor is located on the platform, in a zone diametrically opposite to the Control Building, just behind the VST. E FOROT-Sardenia 15-18 September 2008 The CUTE-SCIDAR@AT4 is located on the platform, in VLTI J2 Station.
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 FOROT-Sardenia 15-18 September 2008
Meteo, DIMM, GSM and MOSP, MASS and LuSci FOROT-Sardenia 15-18 September 2008
DIMM, GSM and MOSP FOROT-Sardenia 15-18 September 2008 SCIDAR-----
Synchronous acquisitions FOROT-Sardenia 15-18 September 2008
GSM and MOSP (Borgnino & al, thisconference)…& nearby buildings FOROT-Sardenia 15-18 September 2008
LUSCI • J. Beckers, 1993 & thisconference • P. Hickson, 2004 & thisconference • - A. Tokovinin SPIE 7013, 2008 FOROT-Sardenia 15-18 September 2008
MASS-DIMM on C11 tube and ASTELCO mount FOROT-Sardenia 15-18 September 2008
Turbulence profiles from MASS FOROT-Sardenia 15-18 September 2008 The altitude weighting functions of MASS and SCIDAR are of different physical nature
Cute-SCIDAR@AT4 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) • - Cn2 for each layer (GL + FA) • - Isoplanatic Angle FOROT-Sardenia 15-18 September 2008
Real time turbulence evolution including and excluding dome turbulence (see Fuensalida et al. 2008, MNRAS, 389, 731) Direct correlation with Seeing from other Profilers or Monitors, wind speed and wind direction Recombination of the turbulence profile in a “MASS-like” structure for immediate comparison SCIDAR real time analysis and first post-processing FOROT-Sardenia 15-18 September 2008
Results 2007-12-17 FOROT-Sardenia 15-18 September 2008
Results 2007-12-18 FOROT-Sardenia 15-18 September 2008
Results 2007-12-19 FOROT-Sardenia 15-18 September 2008
Results 2007-12-20 FOROT-Sardenia 15-18 September 2008
Results 2007-12-21 FOROT-Sardenia 15-18 September 2008
Results 2007-12-22 FOROT-Sardenia 15-18 September 2008
Results 2007-12-23 FOROT-Sardenia 15-18 September 2008
Results 2007-12-24 FOROT-Sardenia 15-18 September 2008
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) • - Cn2 for each layer (GL + FA) • - Isoplanatic Angle FOROT-Sardenia 15-18 September 2008
X-Comparison MASS vs Cute-SCIDAR “MASS-like” structure: FOROT-Sardenia 15-18 September 2008
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 - Cute-SCIDAR averages are synchronized no more than ± 30 sec with respect to MASS data FOROT-Sardenia 15-18 September 2008 more work needed!!!