An XMM-Newton target of opportunity observation of the field around the transient 18.37 s pulsar XTE J0055 $ - $ 727 in the Small Magellanic Cloud ( SMC ) revealed two bright , long-period X-ray pulsars in the EPIC data .
A new pulsar , XMMU J005517.9 $ - $ 723853 , with a pulse period of 701.7 \pm 0.8 s was discovered and 500.0 \pm 0.2 s pulsations were detected from XMMU J005455.4 $ - $ 724512 ( = CXOU J005455.6 - 724510 ) , confirming the period found in Chandra data .
We derive X-ray positions of RA = 00 ^ { h } 54 ^ { m } 55 \aas@@fstack { s } 88 , Dec = –72°45′10 \aas@@fstack { \prime \prime } 5 and RA = 00 ^ { h } 55 ^ { m } 18 \aas@@fstack { s } 44 , Dec = –72°38′51 \aas@@fstack { \prime \prime } 8 ( J2000.0 ) with an uncertainty of 0 \aas@@fstack { \prime \prime } 2 utilizing optical identification with OGLE stars .
For both objects , the optical brightness and colours and the X-ray spectra are consistent with Be/X-ray binary systems in the SMC .