Observation of the candidate persistent Be X-ray binary pulsar 4U 0728-25

The persistent Be accreting pulsars are a subclass of the BeXRBs characterizedby persistently low luminosity (Lx 10^(3435) erg/s) and long pulse period (P> 100 s). Since in these binaries the matter is accreted from the lowdensitywind of the companion star, these systems are a particularly interestinglaboratory to study the emission processes occuring at low accretion rates.Therefore, it is very important to identify and investigate new sources of thistype. To this aim, we propose to observe the Galactic Be pulsar 4U 072825,which is a poorly studied candidate member of this class of sources. Our aim isto examine, at an unprecedented sensitivity level, its spectral and timingproperties, and to test if the description of the other persistent pulsars is applicable also in this case. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]