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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife TIP@GRIS DATA REDUCTION AND CALIBRATION M. Collados
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife TIP@GRIS DATA REDUCTION AND CALIBRATION + Some notions on the Radiative Transfer Equation and Inversion Techniques
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 2 ferroelectric liquid crystals (TIP) δ 1 = 155º δ 2 = 75º θ 1 = 70º θ 2 = 155º Δθ = 50º Polarimetric techniques 4 independent modulation states Fixed retardances θ 2 = θ 2 (Voltage) θ 1 = θ 1 (Voltage) Polarizer Polarizing beamsplitter
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Polarimetric techniques Why a polarizing beamsplitter instead of a polarizer? Spatial modulation (Dual beam) Temporal modulation (Single beam)
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Polarimetric techniques Spatial modulation (Dual beam) Temporal modulation (Single beam) Seeing-induced crosstalk Flatfield-induced crosstalk
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Polarimetric techniques Temporal and Spatial modulation Beam exchange
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Reduction steps Bad pixel correction Dark current subtraction Flatfield correction Telescope + polarimeter calibration Demodulation + Beam merging Residual fringes correction
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 1.- Bad pixel correction raw imageCorrected for bad pixels
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 2.- Dark current subtraction Important Same exposure time as observations
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3.- Flatfield correction CORRECTION FOR Line inclination Beam misalignment λ 1565 nm Important One flat per modulation state
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3.- Flatfield correction λ 1565 nm CORRECTION FOR Line inclination Beam misalignment Important One flat per modulation state
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3.- Flatfield correction λ 1565 nm Modulation state 1
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3.- Flatfield correction λ 1565 nm Modulation state 2
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3.- Flatfield correction λ 1565 nm Modulation state 3
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3.- Flatfield correction λ 1565 nm Modulation state 4
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 4.- Telescope + polarimeter calibration
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife { 4.- Telescope + polarimeter calibration
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Unknowns: 4.- Telescope + polarimeter calibration
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Residual crosstalk Q, U, V ↔ Q, U, V ≈ 1% 4.- Telescope + polarimeter calibration (IV)
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 5.- Demodulation + Beam merging T(t)D(t)D(t) T(t)1 N = T(t) I I = D(t) N // D(t) T(t) = 1 → →→→
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife On-line Stokes images visualization
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 6.- Demodulation + Beam merging Single beamDual beam I V
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 6.- Demodulation + Beam merging Single beamDual beam Q U
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 6.- Demodulation + Beam merging U Q IV
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Routines pro cal15650 lambda=15650.; polarimetric calibration filecal=['27apr14.005','27apr14.009','27apr14.012','27apr14.019', $ '28apr14.001','28apr14.005','28apr14.007', $ '29apr14.002','29apr14.005','29apr14.008','29apr14.011', $ '30apr14.000','30apr14.005','30apr14.008', $ '30apr14.013','30apr14.016', $ '01may14.002','01may14.005','01may14.007', $ '02may14.002','02may14.005','02may14.012', $ '02may14.016','02may14.019', $ '03may14.001','03may14.006','03may14.010','03may14.014', $ '03may14.017','03may14.025','03may14.029', $ '05may14.001','05may14.006'] get_teles,filecal,lambda=lambda,xtau=xtau,/verbose,/display return end
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Routines pro cal27apr14 ; data calibration xtau=[0.9917,174.02,1.0014,536.71] ; using all calib files ; 27 Apr - 5 May fileff=['27apr14.006'] filecal=['27apr14.005'] map='27apr14.000' gris,map,fileff,filecal,lambda=15650.,xtau=xtau,/xtalk return end
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Data handling and preparation prior to analysis (not included yet in standard routines) -Continuum rectification -Wavelength calibration -Stray light (and PSF) evaluation COMPARISON WITH FTS
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Line Identification
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Calculate dispersion
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Wavelength calibrated spectrum
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Continuum rectification 15th order polynomial FTS in redOBS in white
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Continuum rectification OBS in whiteFTS in red
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 2. Spectral Resolution + Stray Light σ teor = 56 mA
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 2. Spectral Resolution + Stray Light FTS in redOBS in white
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife All steps
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3. The radiative transfer equation Synthesis Inversion
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3. The radiative transfer equation Intensity Optical depth S Source function K Absorption matrix RTE (stationary and plane-parallel)
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3. The radiative transfer equation Unno-Rachkovsky equations observer LTE
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3. The radiative transfer equation Zeeman splitting
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3. The radiative transfer equation Intensity Optical depth S Source function K Absorption matrix O Evolution or extintion operator RTE (stationary and plane-parallel)
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 3. The radiative transfer equation Free parameters: B, θ, χ, B 0, B 1, η, Δλ d, a, v Mag. field Source function Line shape Line position with
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Profiles for different field strength
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Profiles for different field inclination
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Profiles for different field azimuth
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife R X Response function 3. The radiative transfer equation Parameter perturbation RTE perturbation Perturbation solution
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Initial model T Synthesis I syn Observation I obs Perturbed profile δI = I syn - I obs Perturbed model δT 4. The RTE inversion
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Existence of solution? Unicity of solution? 4. The RTE inversion
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Least squares 4. The RTE inversion
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 5. The RTE inversion (SIR)
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 5. The RTE inversion (SIR)
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 6. Information obtained from spectral lines 1.- Temperature stratification 2.- LOS velocity stratification 3.- Magnetic field vector stratification 4.- Atomic parameters 5.- Element abundance
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife 6. Information obtained from spectral lines 1.- Temperature stratification 2.- LOS velocity stratification 3.- Magnetic field vector stratification 4.- Atomic parameters 5.- Element abundance
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M. Collados Instituto de Astrofísica de Canarias CASSDA School 20-25 Apr 2015 - Tenerife Magnetic field Westendorp Plaza et al. (2001) 6. Information obtained from spectral lines
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