Transcript Algorithms for CU6

Meeting GHOST2
Participation in CU6
13-14/11/2006 LAM
Overview
• Different deadlines depending on the state
of the workpackages
• rv, Vsini for all types of stars: cold to hot
stars
• General information on spectra
• rv, Vsini on component of multiple system
• Detection of the variability
Algos…
Algo, Single transit analysis
Single transit analysis
Coarse characterization of sources
S650-06000 C.Martayan, A.-M. Hubert
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Lists of abs/Em lines (common with CU8)
Give S/N ratios
Give slopes of spectra
Determine RVS magnitudes, comparisons RVS
vs spectro-photométrie and vs ground-based
photometry
• Use templates/masks for lines and crosscorrelation
Single transit analysis
Coarse characterization of sources
• Other tasks to add ?
• Cycle 2: 10/2006-05/2007
– Define methods
– Specification of requirements
– Obtaining observed and synthetic spectra
• Cycle 3: 05/2007-11/2007
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Define and write algorithms
Observations
Tests with observed and synthetic spectra
Improvement of methods/algo.
Algos…
Single transit analysis
rv & Vsini in Fourier space
S650-08000/09000 Y. Frémat, A. Lobel, C. Delle-Luche, S. Jankov
• rv, use of cross-correlation in Fourier space
• Functional analysis done
• Fortran prototype good results:
– Cold to hot stars
– Vsini=0, rv=20 <rv>:19.75-19.84 for V:6-14
– Vsini=150, rv=20 <rv>:18.94-19.27 for V:6-14
Single transit analysis
rv & Vsini in Fourier space
S650-08000/09000 Y. Frémat, A. Lobel, C. Delle-Luche, S. Jankov
• Cycle 2:
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delivery soft requirements,
soft design,
end of fortran prototype, implementation of java algo.
Tests of java algo, delivery soft products
Validation of soft
• Cycle 3: beginning of Vsini study
Single transit analysis
rv & Vsini by mini distance method
S650-10000 R. Blomme, A. Lobel
• Input: grids of template spectra Teff, logg
(provided by CU8)
• Method defined
• Algo try broadening function, rv shift, best fit
• Other method: Least Square Deconvolution
• Cycle 2: implementation 1st solution direct in java
• Cycle 3: implementation 2nd solution
Algos…
& multiple
transits analysis
Multiple transits analysis
RV & Vsini for multiple line systems
S660-04000 E. Gosset, G. Rauw, Y. Nazé
• Using TODCOR method: 2D cross-correlation
with 2 templates of spectra
• Ratio of flux pre-defined or fitted
• Cycle2: flux ratio fixed, test data to be computed
– Problems of parameters difficult in case of multiple
lines
– Provide a flag to indicate the multiplicity
– Recruitment of 1 postdoc
Multiple transits analysis
Assess source variability
S660-06000 P. De Cat, L. Eyer, A.-M. Hubert, S. Jankov, P. Dubath,
S. Udry
• Drv as function of type of variable
• Detection of the variability in CU6 (CU7 analyses)
• Function of the S/N ratio
– Statistical tests (low S/N)
– Cross-correlation peak (intermediate S/N)
– Line profile variation, study of Em lines (good S/N)
• Cycle2: analysis on low S/N ratio, statistical tests on rv
distributions, prototypes will be developed
• Cycle3: request for simulated data