Xuheng Ding's Homepage
Postdoctoral Researcher at Kavli IPMU
I am currently a Postdoctoral Researcher (Kavli Fellow) in IPMU, the University of Tokyo, working with Prof. John D. Silverman's research group. I obtained my Ph.D. (2012-2017) at Beijing Normal University. After that, I engaged in scientific research at Wuhan University and worked as a postdoc at UCLA with Prof. Tommaso Treu.
My current research focuses on galaxy evolution, strong gravitational lensing, and observational cosmology. I used HST imaging data to study 32 type-1 AGNs to reveal the coevolution of scaling correlations between supermassive black hole growth and its host galaxy at redshift z ~ 1.5. As a co-PI of one JWST cycle-1 program, my research group will use redshift very high-z QSOs to extend the study of the scaling relation to redshift 6. More recently, my HST cycle-30 program was approved, and I will lead the study to confirm eleven very close dual AGN candidates that have the closest separation at z>1. To help people efficiently fit the scientific images of galaxies, QSOs, which are observed by HSC, HST, JWST and CSST, I developed an open-source image modeling software galight.
In 2022 Aug and Sept, I performed the analysis of five quasars selected from SDSS and AEGIS at 1.6 < z < 3.5 that fall within the JWST CEERS area. For the first time, I detected the quasar hosts at z up to 3.5. I also obtained spatially-resolved host morphological structures (spiral arm and bar) not possible with HST.
This Figure demonstrates my 2D decomposition result of SDSS1420 (z∼2) using HST (left) and JWST (right). With JWST, I obtained the morphological structures (spiral arms, bar) not possible using HST for this same target. More details see Ding et al., 2022 ApJL 939L 28D.
In 2022 Nov, I studied two high redshift (z~6.4) low-luminosity quasars imaged with the NIRCam on JWST. I successfully detected starlight from quasar host galaxies at z>6, at a time when our universe was less than a billion years old. This is the first time that quasar host galaxies have been imaged at this cosmic epoch, highlighting the tremendous power of JWST. The detections of these two quasars’ host galaxies at z>6 has achieved the key milestone of measuring their stellar mass and physical size, which provides a decisive step forward in understanding how the growth of SMBHs relates to that of massive galaxies at early cosmic times.
This Figure demonstrates the 2D decomposition result of two quasar at z~6.4. More details see Ding et al., 2022 Nature Under Review.
In addition, I led the Time Delay Lens Modeling Challenge (TDLMC), aiming to assess the present capabilities of lens modeling codes and assumptions and test the level of accuracy of inferred cosmological parameters given realistic mock datasets. I also make predictions for the future lensing of transients such as gravitational wave and FRB events and study their applications in observational cosmology.
I am a member of HSC survey collaboration, COSMOS survey collaboration, H0LiCOW collaboration, and TDCOSMO collaboration.
Research Related
After school life
I am also a guitar player, and I enjoyed filming myself, and playing guitar with friends. Some pieces of my play are presented below. I hope you enjoy them!
Recently I started to learn to play piano, so I haven't posted any new videos :(
However, my new videos will come back soon! Stay tuned!