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Description
All 543 pointed observations of the ROSAT High Resolution Imager (HRI) with exposure times higher than 50 seconds, and performed between 1990 and 1998 in a field of 10 by 10 degrees covering the Large Magellanic Cloud were analyzed, and a source catalogue was produced that contains 397 X-ray sources whose properties have been measured with the HRI. The list was cross-correlated with the ROSAT Position Sensitive Proportional Counter (PSPC) LMC source catalogue of Haberl and Pietsch (1999, A&AS, 139, 277; the HEASARC database LMCROSXRAY) in order to obtain the (PSPC) hardness ratios for the X-ray sources detected by both instruments. 138 HRI sources are contained in the PSPC Catalogue, while 259 sources are new detections. The spatial resolution of the HRI being better than that of the PSPC, source positions could be determined with errors smaller than 15 arcsec which are dominated by systematic errors. After cross-correlating the source catalogue with the SIMBAD database and the Tycho Catalogue, 94 HRI sources were identified with known objects based on their positional coincidences and X-ray properties. Whenever more accurate coordinates were given in catalogues or the literature, the X-ray coordinates were corrected and the systematic error of the X-ray position was reduced. For other sources observed simultaneously with an identified source, the positional coordinates were also improved. In total, the X-ray positions of 254 sources were newly determined. The sources identified in this study include 39 foreground stars, 24 supernova remnants (SNR), 5 supersoft sources, 9 X-ray binaries, and 9 active galactic nuclei (AGN) well-known from the literature. Another 8 sources were identified with known candidates for these source classes. An additional 21 HRI sources were suggested by the authors as candidates for SNR, X-ray binaries in the LMC, or background AGN, because of their spatial extents, hardness ratios, X-ray to optical flux ratios, or flux variability. This database was created at the HEASARC in June 2000 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+AS/143/391">CDS Catalog J/A+AS/143/391</a>, and is derived from Table 4 of the reference. This is a service provided by NASA HEASARC .
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