DISCOVERY OF SAX J1753.5-2349 AND SAX J1806.5-2215 - 2 X-RAY BURSTERSWITHOUT DETECTABLE STEADY EMISSION

We report the discovery with BeppoSAX-WFC of two new X-ray sources tha t were only seen during bursts: SAX J1753.5-2349 and SAX J1806.5-2215. For both sources, no steady emission was detected above an upper limi t of 5 mCrab (2 to 8 keV) for 3 10(5) s around the burst events. The s ingle burst detected from SAX J1753.5-2349 shows spectral softening an d a black body color temperature of 2.0 keV. Following the analogy wit h bursts in other sources the burst very likely originates in a thermo nuclear flash on a neutron star. The first of two burst detected from SAX J1806.5-2215 does not show spectral softening and cannot be confir med as a thermonuclear flash.