Ja En つくば宇宙フォーラム
第158回
Ionization Environment in Star-Forming Galaxies during the Epoch of Reionization
菅原 悠馬 氏
早稲田大学
要旨
ALMA and JWST have been pushing up the redshift frontier to z~14 and pioneering metal emission line studies in star-forming galaxies at $z > 5$. These telescopes are powerful tools for high-redshift probes even on their own, but their multi-wavelength synergy is opening a new window in the high-redshift studies. In this talk, I will start my talk from basics of the high-redshift observations and physics of emission lines in ionized regions. The metal emission lines provide us with line diagnostics to investigate ionized interstellar media featured at high redshift, including intense star formation, strong ionization, high electron density, and characteristic elemental abundances. Our ALMA+JWST project, RIOJA, is exploring these properties of UV-bright galaxies during the epoch of reionization, with ALMA + NIRSpec IFU 3d cubes as well as NIRCam images. These multi-wave emission line observations show that many of these UV-bright galaxies experience an intense starburst but have chemically matured gas-phase properties. In addition, the multi-wave lines provide hints to multi-phase ionized regions, suggesting a complex ionization structure in high-redshift galaxies. If time permits, I would like to present my ongoing research as a topic for discussion.