During a BeppoSAX observation of the X-ray source XB 1746-371 located in the globular cluster NGC 6441 a type I X-ray burst , parts of 4 intensity dips , and energy dependent flaring were detected .
The dips repeat every 5.8 \pm ^ { 0.3 } _ { 0.9 } hr and show no obvious energy dependence .
If the dips are due to electron scattering this energy independence implies an abundance > 130 times less than solar , confirming an earlier measurement .
Since the overall cluster abundance is close to solar this low abundance is unexpected .
Photoionization of the absorbing material , obscuration of an extended source , and variations in multiple components that combine to produce an apparent energy independence are all excluded .
Thus , the nature of the dips remains uncertain .
The best-fit model to the overall 0.3–30 keV spectrum is a disk-blackbody with a temperature of 2.82 \pm 0.04 keV , together with a cutoff power-law with a photon index of -0.32 \pm 0.80 and a cutoff energy of 0.90 \pm 0.26 keV .
Absorption , consistent with the optical extinction to NGC 6441 of { ( 0.28 \pm 0.04 ) \times 10 ^ { 22 } } atom cm ^ { -2 } is required .
All previous best-fit spectral models for this source are excluded at high confidence .
The spectrum is dominated by the blackbody-like component , with the cutoff power-law only contributing an average of 12 % of the 1–10 keV flux .
During flaring intervals the contribution of this component decreases to \sim 6 % with variations in the intensity of the blackbody-like component being responsible for most of the flaring activity .