Boris Goncharov, Scientist
Albert Einstein Institute (AEI)

Xiaoming Bi
PhD student, AEI
Xiaoming is pursuing his PhD on gravitational-wave astrophysics. His recent work includes modelling how astronomical bodies respond to gravitational waves, alongside broader interests in PTA science and cosmology.

Jacob Cardinal Tremblay
PhD student, AEI
Jacob is pursuing his PhD on searches for continuous gravitational waves and multimessenger counterparts of supermassive black hole binaries with pulsar timing arrays.

• "A Multi-Messenger Search for the Supermassive Black Hole Binary in 3C 66B with the Parkes Pulsar Timing Array" (arXiv). This work delivers the strongest PTA constraints to date on the 3C 66B candidate, partially rules out electromagnetic parameter space, and introduces a joint electromagnetic plus gravitational-wave likelihood framework for targeted multimessenger PTA analyses.

Sharon Mary Tomson
PhD student, AEI
Sharon is pursuing her PhD on methods to search PTA data for supermassive black hole binary mergers and gravitational-wave memory signals.

• "Search for Gravitational-wave Memory in PPTA and EPTA Data: A Complete Signal Model" (arXiv; ApJL). This is the first full search in PTA data for late inspirals and mergers using numerical-relativity waveforms with nonlinear gravitational-wave memory, placing astrophysically meaningful limits, including exclusion of 10¹⁰ M_⊙ mergers out to 700 Mpc at 95% credibility.
• "Finding Supermassive Black Hole Binary Mergers in Pulsar Timing Array Data" (arXiv). This paper presents the first proof-of-principle PTA framework to search for complete supermassive black hole merger signals, modelling inspiral, merger, ringdown, and memory together in one analysis.

Arian Leon von Blanckenburg
PhD student, AEI
Arian is pursuing his PhD on PTA data analysis methods, including new mathematical bases and estimators for stochastic gravitational-wave searches.

Shubhit Sardana
AEI intern & BS-MS student, IISER Bhopal
Shubhit is pursuing an integrated BS-MS degree and works on the astrophysical interpretation of PTA signals, with recent projects on supermassive black hole binary populations, PTA noise modelling, and targeted standard-siren cosmology.

• "The Targeted Standard Siren Cosmology with Pulsar Timing Arrays" (arXiv). We show that targeted PTA searches for known supermassive black hole binaries can turn them into standard sirens and, for the first time, potentially measure the Hubble constant with PTA data at competitive precision.
• "Reading signatures of supermassive binary black holes in pulsar timing array observations" (arXiv; Nature Communications). This work shows that improved hierarchical noise modelling brings PTA-inferred background properties into agreement with the canonical supermassive black hole binary picture, recovering consistency with the expected strain spectral index of -2/3 and finding no evidence for environmental hardening or eccentricity.
• "Ensemble noise properties of the European Pulsar Timing Array" (arXiv; MNRAS). This paper introduces a new numerical marginalization procedure for hierarchical PTA noise inference at negligible computational cost, and reports the first measurement of ensemble spin-noise and dispersion-measure-noise distributions from EPTA data.

Yonghao Liu
PhD student, The Hong Kong University of Science and Technology
Yonghao is pursuing his PhD on particle physics and cosmology, with recent work connected to pulsar timing arrays and dark-matter-related signals.

• "Probing Ultralight Axion-like Dark Matter: A Pulsar Timing Arrays-Pulsar Polarization Arrays Synergy" (arXiv). This work develops, for the first time, a joint PTA-PPA methodology for ultralight axion-like dark matter searches, including the cross-correlation structure needed for combined timing and polarization analyses.

Xuan Tao
Visiting AEI PhD student from Huazhong University of Science and Technology
Xuan works on new methods to detect supermassive black hole inspirals in pulsar timing arrays.

Kanyuni Iemoto (incoming)
Incoming student
Kanyuni will be joining the team soon.

Rinat Kagirov Visiting intern, AEI → M.Sc. student, the University of Oxford
We evaluated the prospects of Pulsar Timing Arrays to detect gravitational wave backgrounds from the early Universe through the gravitational wave foreground created by supermassive black hole binaries.

Clemente Smarra
PhD student, SISSA → Postdoctoral researcher, University of Padua
We worked on searches for ultralight dark matter while Clemente was a PhD student at SISSA, Italy.

• "The second data release from the European Pulsar Timing Array: VI. Challenging the ultralight dark matter paradigm" (arXiv; PRL). This paper showed, for the first time with PTA data, that ultralight dark matter in a key mass range cannot make up all of the local dark matter density, directly challenging the simplest PTA-accessible ultralight-dark-matter scenario.
• "Constraints on conformal ultralight dark matter couplings from the European Pulsar Timing Array" (arXiv; PRD). This paper places improved PTA bounds on conformal ultralight-dark-matter couplings, extending PTA sensitivity beyond purely gravitational scenarios and constraining scalar-tensor models through pulsar timing.