We report on spectral and timing analysis of Beppo SAX data of the 13.6 s period transient X-ray pulsar EXO 053109-6609.2 .
Observations were carried out in March 1997 and October 1998 , catching the source during a high and a low emission state , respectively .
Correspondingly , the X-ray luminosity is found at a level of 4.2 \times 10 ^ { 37 } erg s ^ { -1 } 
and 1.5 \times 10 ^ { 36 } erg s ^ { -1 } in the two states .
In the high state the X-ray emission in the energy range 1–100 keV is well fitted by an absorbed power–law with photon index \Gamma \sim 1.7 plus a blackbody component with a characteristic temperature of \sim 3.5 keV .
Moreover , we find an evidence of an iron emission at \sim 6.8 keV , typical feature in this class of sources but never revealed before in the EXO 053109-6609.2 spectrum .
In the low state an absorbed power–law with \Gamma \sim 0.4 is sufficient to fit the 1–10 keV data .
During Beppo SAX observations EXO 053109-6609.2 display variations of the pulse profile with the X-ray flux : it showed single peaked and double peaked profiles in the low and high state , respectively .
Based on these two observations we infer a spin–up period derivative of - ( 1.14 \pm 0.08 ) \times 10 ^ { -10 } ss ^ { -1 } .
By comparing these with other period measurements reported in literature we find an alternating spin-up and spin-down behaviour that correlates well with the X-ray luminosity .