Contact:  otto.akseli.hannuksela[AT]gmail.comLocation:  Hong Kong
We seek applicants with preferred expertise in strong gravitational lensing who are interested in expanding their research focus to strong gravitational lensing involving gravitational waves. The ideal candidate will have considerable expertise in constructing lens models for galaxies (or galaxy clusters) as constrained by multiply-lensed light images, familiarity with analyzing optical images, and will be committed to working with local experts to incorporate additional constraints provided by multiply-lensed gravitational-wave events. Current ground-based gravitational-wave detectors have the potential to reveal dark matter (DM) substructures through high-precision timing of the arrival of multiply-lensed gravitational waves.
We envision that the combination of constraints from both light and gravitational waves will provide immunity from stellar microlensing, and reveal the nature of such sub-structures at high precision. If such small-scale structures can be confidently linked with dark matter model predictions, their existence would either provide strong support for or alternatively rule out the current standard cosmological cold dark matter paradigm. Apart from this work, involving a collaboration between research teams at CUHK and HKU, the candidate is strongly encouraged to pursue his or her independent research line. Local expertise is provided by the research teams at both CUHK and HKU, who are experts in the lensing of gravitational waves and light rays, respectively [e.g. 1,2].
At CUHK, since 2016, the group has built tools to detect, analyse, and make use of gravitational-wave lensing with ground-based gravitational-wave detectors in isolation or together with electromagnetic imaging [e.g. 1]. At HKU, the group is a leading expert in using traditional gravitational lensing of light rays to elucidate the nature of DM, including investigating investigating the linkage between dark matter substructures and their model predictions, such as subhalos (e.g., WIMPs) and pervasive density modulations (e.g., Axions) [e.g. 2].
There are furthermore three dark matter groups at CUHK, specialising in numerical simulations, indirect detection, and theory, and expertise in theoretical aspects of dark matter modelling. The postdoc’s role would be to fill the role of a lens modelling expert in the joint endeavor to connect these two branches of lensing and pursuing dark matter studies. Apart from the joint work, the postdoctoral researcher is strongly encouraged to freely integrate and work with these groups and to develop their own independent research line throughout the study, with 50% time allotted to independent research.
Applicants should possess a PhD in Physics, Astronomy, or a related field and have a track record in lens modelling. Expertise in implementing new strong lensing analyses and modelling (using e.g. lenstronomy or an equivalent strong lens modelling software), a publication track record in substructure lensing, and experience implementing Bayesian analysis models are highly advantageous. Applicants from gravitational-wave lensing background are also welcome to apply.
Application Procedure Interested candidates should submit a cover letter, curriculum vitae, and research statement outlining their interests and qualifications and request for two references to be sent to (https://forms.gle/1aiAF7FCUCVgUQai8 or oahannuksela@cuhk.edu.hk) by October 10. Applications will be reviewed immediately and continue until the position is filled (early applications are strongly encouraged; applications received before August may be able to apply for RGC Postdoctoral Fellowship). The start date for the position is between Fall 2024 (October 2024) and Fall of next year (December 2025) (start date is negotiable).
The salary range is 29,845-34,585 HKD (~3,800-4,400 USD) per month depending on experience.
Contacts:
CUHK gravitational-wave group:
Otto A. Hannuksela https://newww.phy.cuhk.edu.hk/teaching_staff/otto-a-hannuksela
HKU gravitational lensing group:
Jeremy Lim http://hub.hku.hk/rp/rp00745
CUHK dark matter groups:
Kenny C. Y. Ng https://newww.phy.cuhk.edu.hk/teaching_staff/kenny-c-y-ng
Tsang Keung Chan
https://newww.phy.cuhk.edu.hk/teaching_staff/chan-tsang-keung
Ming-Chung Chu
https://newww.phy.cuhk.edu.hk/teaching_staff/chu-ming-chung
[1] https://arxiv.org/abs/2004.13811
[2] https://www.nature.com/articles/s41550-023-01943-9