Parkes observations for project P1168 semester 2024OCTS_01

Full description

We discovered seven pulsars in the globular cluster Terzan 1 with the Green Bank Telescope (GBT) and have been timing them over the last 1.5 year with the Parkes Telescope. The discoveries include five fully-recycled millisecond pulsars (MSPs) with spin periods between 3 and 6 ms, a partially-recycled 11-ms MSP, and a pulsar with an unusually long spin period of 134 ms. With our Parkes timing campaign, we have confirmed that all seven pulsars are isolated, consistent with Terzan 1 being a core-collapsed cluster. The 134-ms pulsar has a characteristic age of 23 Myr and is thus an especially interesting discovery in the context of pulsar formation via electron-capture rather than core-collapse supernovae. (We will submit our paper detailing these results by autumn 2024.) Student collaborator Bhakta discovered an eighth MSP in Ter 1 and will use the P1168 dataset to time it. We have been granted continuing status through 2024OCT, with which we will continue timing Terzan 1 at Parkes in order to obtain long-baseline timing solutions. This long-term timing will yield measurements of proper motion and potentially additional spin derivatives that together can be used to probe the cluster dynamics, constrain intrinsic spin properties of the pulsars, and confirm the young vs. old nature of the 134 ms pulsar. In addition to timing, we will probe the pulsars' polarization properties and the Galactic magnetic field in the direction of Terzan 1. We will also search these observations for new pulsars that may have been missed in previous observations.