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4. Radio source catalogue

4.1. The tables

Tables 2 to 6 are the catalogues of discrete radio sources found in the SMC surveysgif. In these tables, we used the same format as for the paper on the LMC (Paper IV) i.e. the source name (Col. 1) is derived from the standard IAU system of source nomenclature (Dickel et al. 1987; Lortet et al. 1994), namely - SMC Bhhmm-ddmm (e.g., SMC B0054-7254). The letter ``B" in Col. 1 indicates that the source positions (Cols. 2 and 3) are for equinox and equator B1950. For easier cross-checking we have adopted the reference source name based on the position at the highest frequency, since that position will be the most accurate. In Col. 4 the symbol (e) is used to flag sources that are significantly extended. The definition of extension is discussed below in Sect. 4.2. The integrated flux densities are listed in Col. 5.

Table 7 gives the cross-references for all sources in Tables 2 to 6. Column 3 (Other Names and Comments) uses the following abbreviations:
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4.2. Source extension

The basket-weaving analysis, gridding and scanning process used during the observations slightly broadens the full width half maximum (FWHM) beam size. We have determined the effective beam size from the distribution of the fitted widths after excluding the tail of very extended sources. We excluded sources greater than 5 times the median size and then recalculated the median until the process convergedgif. The definition adopted here for a significantly extended source is that the fitted size (solid angle) of the source is twice that of the effective beam size. The true angular size of the sources is the observed size deconvolved with the effective beam size. Adopting this definition, between 5% and 20% (depending on the observing frequency) of all our sources in the SMC field are extended. For details about nominal beam size, effective beam size, uncertainty in the effective beam size and the number of extended sources, see Table 8 (click here).

  table275
Table 8: Nominal and effective beam sizes, standard deviation of effective source sizes and number of sources considered as clearly extended


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