We report on BeppoSAX observations of the X-ray transient XTE J0421+560 in quiescence 156 , 541 , and \sim 690 days after the maximum of the 1998 April outburst .
In the first observation the source was soft with a power-law photon index , \alpha , of 4.0 \pm ^ { 1.9 } _ { 0.9 } and absorption , { N _ { H } } , of ( 1.1 \pm ^ { 4.9 } _ { 1.1 } ) \times 10 ^ { 21 } atom cm ^ { -2 } .
In the second observation , the source brightened by a factor \sim 15 in the 1–10 keV energy range , became significantly harder with \alpha = 1.86 \pm ^ { 0.27 } _ { 0.32 } and was strongly absorbed with { N _ { H } = ( 4.0 \pm 0.8 ) \times 10 ^ { 23 } ~ { } atom~ { } cm ^ { -2 } } .
There is evidence for a narrow emission line in both spectra at \sim 7 keV .
In the third observation , the source had faded by a factor \mathrel { \hbox { \hbox to 0.0 pt { \lower 2.365 pt \hbox { $ \sim$ } } \kern - 3.0 pt \raise 1.72 pt \hbox { $ > $ } } } 8 from the previous observation to below the BeppoSAX detection level .
It is possible that these variations result from orbital motion of a compact object around the B [ e ] star companion with the intense , absorbed , spectrum arising during passage through dense circumstellar material .
If this is the case , the system may be continuing to exhibit periodic activity .