NICER observation list: Target ID 866301

Recently, a new neutron-star LMXB was discovered in the globular cluster Terzan 6. This source, X2, has been classified as a candidate transitional millisecond pulsar (tMSP). Usually, X2 has luminosities between 2.4e33 and 6e34 erg/s but RXTE monitoring of Terzan 6 suggests that in rare instances X2 enters an outburst state (>1e36 erg/s). In one of these outburst states indications of X-ray pulsations were seen in a short RXTE observation. We propose NICER monitoring of Terzan 6 to catch X2 in an outburst state and confirm the presence of pulsations. We request 114x0.5ks observations with a 2-day cadence. Although the chances of catching an outburst are small (20% in Cycle 7), identification of X2 as a tMSP would add a valuable new member to a very small class of sources.