A new pulsating X-ray source , AX J183220 - 0840 , with a 1549.1-s period was discovered at R.A . = 18 ^ { h } 32 ^ { m } 20 ^ { s } and Dec . = -8 ^ { \circ } 40 ^ { \prime } 30 ^ { \prime \prime } ( J2000 , uncertainty = 0 \farcm 6 ) during an ASCA observation on the Galactic plane .
The source was observed two times , in 1997 and in 1999 .
A phase-averaged X-ray flux of 1.1 \times 10 ^ { -11 } ergs cm ^ { -2 } s ^ { -1 } and pulsation period of 1549.1 \pm 0.4 s were consistently obtained from these two observations .
The X-ray spectrum was represented by a flat absorbed power-law with a photon-index of \Gamma \simeq 0.8 and an absorption column density of N _ { H } \simeq 1.3 \times 10 ^ { 22 } cm ^ { -2 } .
Also , a signature of iron K-shell line emission with a centroid of 6.7 keV and an equivalent width of approximately 450 eV was detected .
From the pulsation period and the iron-line feature , AX J183220 - 0840 is likely to be a magnetic white dwarf binary with a complexly absorbed thermal spectrum with a temperature of about 10 keV .