Pulsar Bonanza! Ten New Millisecond Pulsars Discovered in Globular Cluster Terzan 5

Astronomers have struck gold in a globular cluster known as Terzan 5, uncovering a treasure trove of ten new millisecond pulsars (MSPs). This exciting discovery, detailed in a recent arXiv preprint, not only pushes Terzan 5 to the top of the "most pulsar-rich cluster" list but also offers valuable insights into the evolution of these fascinating objects.

Integrated pulse profiles of all the newly discovered pulsars in Terzan 5. These plots are obtained after summing together individual profiles from different epochs and aligning the profiles with respect to a reference template profile. Credit: Padmanabh et al., 2024.

What are Pulsars and Millisecond Pulsars?

Pulsars are super-dense, rapidly spinning neutron stars, the collapsed cores of massive stars. They emit beams of electromagnetic radiation like a cosmic lighthouse, with their rotation period defining their "pulse." Millisecond pulsars are a special breed, spinning exceptionally fast with periods less than 30 milliseconds.

Globular clusters are tightly bound collections of hundreds of thousands to millions of stars. Terzan 5, located roughly 18,800 light-years away in our Milky Way's bulge, was already known to harbor a significant pulsar population. This latest discovery adds ten more to the list, bringing the total to a record-breaking 49 pulsars!

The newfound pulsars were detected using the powerful MeerKAT radio telescope. By observing Terzan 5 at specific radio frequencies, astronomers were able to pick up the telltale pulsating signals emitted by these stellar remnants.

Interestingly, nine out of the ten newly discovered pulsars appear to be locked in a cosmic dance with companion stars. Four likely have white dwarf companions, while one, Ter5ao, stands out as a potential double neutron star system. This binary system, with its massive companion and rapid spin, could be a rare and exciting find for future study.

The presence of so many pulsars in Terzan 5 is a valuable resource for astronomers. Studying these objects can provide clues about the formation and evolution of binary star systems, the densities of globular clusters, and the properties of neutron stars themselves.