Oral Presentation

Quasar Environments at High Redshift: From HSC and PFS to Roman

Author(s): Masafusa Onoue (Waseda U.)

Presenter: Masafusa Onoue (Waseda University)

I will discuss the recent progress on the understanding of high-redshift quasar environments in the host galaxy and the protocluster scale. In the first half of the presentation, I will present the first results from an open-use Subaru/PFS observation of a quasar field at z = 6.6, where HSC NB926 imaging has revealed a significant overdensity of Lyman-alpha emitters over a scale of R ~ 50 Mpc. Leveraging PFS's wide-field multi-fiber capability, we investigate the three-dimensional structure of this rich environment hosting a billion-solar-mass black hole. The line profiles of spectroscopically confirmed LAEs also enable us to search for surrounding broad-line quasars and double-peaked LAEs, which indicate reionization of the local IGM by the central quasar.

In the second half, I will present our recent JWST observations of the z>6 HSC quasars and, if time allows, introduce recent progress in the preparation for high-redshift quasar observations with the Nancy Grace Roman Space Telescope, with a particular focus on the collaboration between the Subaru community and Roman.