CITA Postdoctoral Fellow Claire Ye has been awarded the 2023-25 Jeffrey L. Bishop Fellowship in recognition of her outstanding research on dense star clusters.

Dr. Ye studies the dynamical evolution of compact objects in globular clusters, especially the interactions between neutron stars and black holes, the birth and life of millisecond pulsars and the formation of gravitational wave sources. She is an expert in simulating dense star clusters using N-body dynamics codes, particularly Cluster Monte Carlo (CMC). Her recent paper (arXiv:2402.12444) shows that mass segregation in dense star clusters could naturally lead to a correlation between the component masses in a merging black hole binary and the redshift at which it merges.

Two of her earlier publications were distinguished with the . The papers ‘On the Rate of Neutron Star Binary Mergers from Globular Clusters’ (Ye, C. S., et al. 2020, ApJL, 888, L10-22.) and ‘Modeling Dense Star Clusters in the Milky Way and Beyond with the CMC Cluster Catalog’ (Kremer, K., Ye, C. S., et al. 2020, ApJS, 247, 48) were in the top 1% of most cited articles in the Astronomy and Astrophysics subject category. .One of the most cited papers from North America published across the entire IOP Publishing journal portfolio for 2020-2022.

Before joining the Canadian Institute for Theoretical Astrophysics, Claire earned her Ph.D. at the Ìý²¹²Ô»åÌý at Northwestern University. She is originally from Southern China and got her Bachelor’s degree in Physics at Zhejiang University in the beautiful city of Hangzhou.

The Jeffrey L. Bishop Fellowship was made possible by a generous gift of Mrs. Muriel Simmons in honour of her son Jeffrey Bishop who died in a car accident shortly after he left CITA. Jeffrey was one of CITA’s first postdoctoral fellows. His family contributes the fund to four institutions that he attended (Princeton, Chicago, CITA and Columbia).

Xinyu’s research focuses on two different aspects of theoretical astrophysics: high energy astrophysics and cosmology. He is particularly interested in the physical mechanisms behind various astrophysical phenomena.At CITA, Xinyu has been working on the astrophysics of compact objects, especially neutron stars and magnetars where strong magnetic fields, outflow and neutrinos can lead to new physics and observational signatures. Together with his collaborators, he proposed a new efficient mechanism of dissipating magnetic energy through the collision of Alfven waves. H
e also performed the simulation of neutron star post-merger disk to study the effect of neutrino fast flavour conversion triggered by the neutrino self-interaction. Such mechanism is found to boost the lanthanide abundances of the r-process nucleosynthesis. Additionally, he demonstrated that strong outflow from compact objects can accelerate the compact object, a new phenomena named as negative dynamical friction.

Apart from that, Xinyu is also interested in the cosmology with Fuzzy Dark Matter, a new dark matter model described a complex scalar field of ultralight bosons. He developed a numerical code and employed it to study the novel small-scale structure from the interference of the scalar field, including soliton cores, vortex lines and filaments. Future observations or non-detections of these small-scale structures may serve to constrain the fuzzy dark matter model.

Before coming to CITA, Xinyu received his PhD in physics from Columbia University in 2019 under the supervision of Prof. Andrei Beloborodov and worked with Prof. Yuri Levin. Both professors are former CITAzens and recipients of the Beatrice and Vincent Tremaine Fellowship.