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work:wp6 [2015/03/27 17:02] persiawork:wp6 [2015/03/30 13:43] (current) persia
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 +==== WP6. Spectroscopic analysis ====
 +
 +
 +^Responsible: INAF |
 +|Ennio Poretti |
 +
 +
 +The space mission CoRoT and Kepler observed hundreds of A-F type stars locate
 +
 +
 +inside the instability strip. Spectroscopic campaigns in the framework\\ 
 +of three ESO Large Programmes (LPs)  were performed and some papers were published (see below). \\ 
 +They discuss in details the comparison between the models and the results from spectroscopic\\ 
 +mode identification. This task was very difficult due to the extreme complexity\\ 
 +of the pulsational content and a full comprehension of the rotational effects.\\ 
 +As a final output, the most powerful results were obtained on stars with a \\ 
 +clear frequency pattern only.\\ 
 +\\ 
 +The HARPS spectra  of A-F stars are now included in the spectroscopic\\ 
 +archive built in the context of the FP7-Space SpaceInn project. The spectra\\ 
 +are fully reduced in terms of careful determination of the physical parameters,\\ 
 +rotational velocities, and mean line-profiles. No extra work is foreseen on the \\ 
 +determination of these quantities. The goal of the SpaceInn archive is to make\\ 
 +the spectra available to the community for a deep analysis in function of \\ 
 +the spectral class and/or variability type. This is what we intend to perform in \\ 
 +the PERSIA project for A-F stars. Unexploited  \\ 
 +spectra are available on HD 181555, HD 172189, HD 171834, HD 174532, HD 44195, \\ 
 +HD 170699, HD 43338, and HD 170133. The spectra of \\ 
 +HD 49434 (Uytterhoeven et al. 2008, A&A 489, 1213), \\ 
 +HD 50844 (Poretti et al.  2009, A&A 506, 85), \\ 
 +HD 174936 (Garcia Hernandez et al. 2009, A&A 506, 79),\\ 
 +HD 50870 (Mantegazza et al. 2012, A&A 542, A24), \\ 
 +HD 174966 (Garcia Hernandez et al. 2013, A&A 559, A63),\\ 
 +HD 51844 (Hareter et al. 2014, A&A 567, 124), and \\ 
 +HD 144277 (Zwintz et al. 2014, A&A 567, A4) \\ 
 +are also available for this kind of new  analysis.\\ 
 +\\ 
 +When developing the tools of a more detailed \\ 
 +comprehension of the rotational effects the INAF team will go back to the spectra and \\ 
 +compare predictions with observations in order to test we are going in the\\ 
 +right direction. These kind of tests  will be performed by means of   \\ 
 +codes supplied by other partners and existing software (e.g., FAMIAS). This will give us \\ 
 +back  tighter constraints on the models, in a sort of virtuous circle. \\ 
 +\\ 
 +Without the efforts programmed in the PERSIA project the pulsational\\ 
 +content of A-F stars will still remain not understood and this will have a \\ 
 +negative feedback in future missions, PLATO in particular. This should be\\ 
 +a frustrating insuccess for the asteroseismology technique, especially if\\ 
 +considering the large spectroscopic database available and the richness of\\ 
 +physical information contained in the line-profile variations.\\ 
 +For instance the age determination will remain limited to the lower part of the \\ 
 +Main Sequence, leaving the datation of the exoplanetary systems\\ 
 +around A-F stars an inaccurate technique.
 +
 +
 +=== Tasks  (TBD) ===
 +
 +
 +    * Proposals, observations, data reduction
 +    * …TBD
 +
 +
 +=== Deliverables ===
 +
 +
 +    * Particular spectroscopic time series of interest for theoretical models
 +    * Partial mode identification for a small set of stars
 +    * …TBD
 +
 +
 +\\