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StarFinder

Involved people at OAB: Diolaiti, Parmeggiani.

StarFinder is a code for high precision astrometry and photometry of crowded fields, designed for Adaptive Optics well-sampled diffraction limited images with high and low Strehl ratio. The code is the result of a joint collaboration between the Astronomy Department of the Bologna University (Orazio Bendinelli and Emiliano Diolaiti), the Working Group on Adaptive Optics at ESO (Laird Close, Douglas Currie and Domenico Bonaccini) and the Bologna Observatory (Gianluigi Parmeggiani). The main peculiarity of the code is the fact that the PSF is extracted directly from the CCD frame, to take into account the actual structure of the instrumental response and the atmospheric effects. The PSF is used as a template for all the stars of the field, which are accepted on the basis of their correlation coefficient with the template. The code has been successfully applied to AO images, like the well-sampled, high Strehl PUEO frame of the Galactic Center, which contains about 1000 detectable stars in a filed of view of 13X13 arcsec, to HST undersampled data handled by dithering techniques like the starburst galaxy NGC 1569, observed with the NICMOS camera. The application of the code to low Strehl images or undersampled data gives results comparable to those attainable by other methods. The code is written in IDL language and organized in the form of a self- contained widget-based application, provided with a series of tools for data visualization and analysis. It has been tested on Windows and Unix platforms supporting IDL v.5.0 or later. StarFinder is also reasonably fast: the analysis of the Galactic Center image requires between 5 and 10 minutes on a normal PC (Pentium Pro - 64Mb RAM - 350MHz). The StarFinder package and its technical documentation can be obtained on request to E. Diolaiti (diolaiti@bo.astro.it), writer and maintainer of the code, or are directly available through World Wide Web at the home page of Bologna Observatory.



next up previous contents
Next: Instruments and Techniques Up: Numerical studies and Previous: Turbulence