  We present the Brera Multi-scale Wavelet Chandra (BMW-Chandra) source
catalogue drawn from essentially all Chandra ACIS-I pointed observations with
an exposure time in excess of 10ks public as of March 2003 (136 observations).
Using the wavelet detection algorithm developed by Lazzati et al. (1999) and
Campana et al. (1999), which can characterise both point-like and extended
sources, we identified 21325 sources. Among them, 16758 are serendipitous, i.e.
not associated with the targets of the pointings. This makes our catalogue the
largest compilation of Chandra sources to date. The 0.5-10keV absorption
corrected fluxes of these sources range from 3E-16 to 9E-12 erg/cm2/s with a
median of 7E-15 erg/cm2/s. The catalogue consists of count rates and relative
errors in three energy bands (total, 0.5-7keV; soft, 0.5-2keV; and hard,
2-7keV), where the detection was performed, and source positions relative to
the highest signal-to-noise detection among the three bands. The wavelet
algorithm also provides an estimate of the extension of the source. We also
extracted source counts in four additional energy bands, SB1 (0.5-1keV), SB2
(1-2keV), HB1 (2-4keV), and HB2 (4-7keV).

High Energy Astrophysical Phenomena