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Description
SPECFIND is a new tool to extract cross-identifications and radio continuum spectra from radio catalogues contained in the VIZIER database of the CDS. It is designed to handle radio surveys of very different resolutions and sensitivities. Power laws are fitted to the radio spectra, resulting in the determination of a power law slope and a zero-point. SPECFIND has been applied to 22 survey catalogues at 11 different frequencies (159 - 8400 MHz) containing a total of 3.5 million sources, leading to 757894 independent radio cross-identifications and 66866 independent radio spectra with more than two independent frequencies. The code was tested and its results validated by a comparison between the spectral indices found by SPECFIND and those determined by other authors. The determined spectral indices have an error of about +/-0.3. Negative spectral indices have smaller errors, while the error of positive spectral indices can be larger, mainly because of the occurrence of a peak in the spectrum. The code is quite rapid (less than 3 hr running time on a standard PC for 3.5 million sources) and since it is written in C, it can be run on virtually all PCs with at least 512~MB RAM. It produces an output of variable format that can be adapted easily to the purpose of the user. The results of the spectrum identification process are provided as a master table, where a spectrum is attached to each radio source. Due to the SPECFIND algorithm, different radio components of the same physical source can have somewhat different slopes and zero-points. The SPECFIND subdirectory contains the code (in C) and the data used to generate the catalogue, as well as a user manual (manual.ps). For compilation please IMPERATIVELY read the README file stored in the SPECFIND subdirectory.
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