Youngest white dwarf companion found in millisecond pulsar system

Discovery of binary star pair

A team from Italy and Germany announced the finding in a paper published in Astronomy and Astrophysics. Greta Ettorre, who holds a Ph.D., is the study's lead researcher and she studies at the Alma Mater Studiorum University of Bologna. They located the system within the globular cluster NGC 362D approximately 29,300 light-years away. The pulsar rotates with a period of only 5.83 milliseconds and spins more than 10,000 times per minute.

Formation process explained by authors

Millisecond pulsars form in binary systems where mass transfers from an evolving companion to a slowly rotating neutron star. This transfer gives the neutron star angular momentum that makes it spin rapidly as a cosmic lighthouse. The companion star COM-NGC 362D is now a proto-white dwarf representing an unusual evolutionary stage. Most stars become white dwarfs eventually but this specific pairing is exceptionally young for such a system.

Significance of the research findings

Globular clusters serve as excellent hunting grounds because high stellar density increases the likelihood of neutron star companions. Neutron stars are extremely dense objects that can have two solar masses and measure only 12 km in diameter. Finding this specific binary system helps astronomers understand how massive stars explode as core-collapse supernovae to create these rare objects.