092422

We have identified a possible candidate transitional millisecond pulsar (tMSP)in the globular cluster Terzan 6. It shows type-I X-ray bursts eclipses andusually has X-ray luminosities of (1.3-60)e33 erg/s. The X-ray/radio behavior ofthe source suggests it may be a tMSPs or an accreting millisecond X-ray pulsar(AMXP). During a rare outburst state ( and amp gt 1e36 erg/s) we observed indications forX-ray pulsations at 463.5 Hz strengthening the case for a tMSP/AMXPinterpretation. We propose a 120 ks XMM ToO observation to constrain the orbitalperiod of the source confirm the presence of pulsations and search forsub-luminous disk state behavior (only seen in tMSPs). With our observation wewill determine whether the source can be considered a strong candidate tMSP or a regular AMXP. [truncated! Please see actual data for full text]