During a BeppoSAX observation of the low-mass X-ray binary dip source XB 1323 - 619 a total of 10 type I X-ray bursts and parts of 12 intensity dips were observed .
During non-bursting , non-dipping intervals , the 1.0–150 keV BeppoSAX spectrum can be modelled by a cutoff power-law with a photon index of 1.48 \pm 0.01 , a cutoff energy of { 44.1 ^ { +5.1 } _ { -4.4 } } keV together with a blackbody with kT of 1.77 \pm 0.25 keV contributing \sim 15 % of the 2 – 10 keV flux .
Absorption equivalent to { 3.88 \pm 0.16 \times 10 ^ { 22 } } atom cm ^ { -2 } is required .
The dips repeat with a period of 2.938 \pm 0.020 hr and span 40 % of the orbital cycle .
During dips the maximum reduction in 2–10 keV intensity is \sim 65 % .
The spectral changes during dips are complex and can not be modelled by a simple absorber because of the clear presence of part of the non-dip spectrum which is not absorbed .
Spectral evolution in dipping can be well modelled by progressive covering of the cutoff power-law component which must be extended , plus rapid absorption of the point-source blackbody .
One of the bursts is double and 4 of the bursts occurred during dipping intervals .
These bursts have 2–10 keV peak count rates reduced by only 22 % on average from those occurring outside the dips , and are not heavily absorbed .
One explanation for this lack of absorption is that the bursts temporarily ionize the absorbing material responsible for the dips .