莱曼连续谱星系的搜寻及其性质的研究
The searching of Lyman continuum galaxies and their properties
Lyman continnum (LyC) photons (rest-frame λ<912 angstrom ), which are produced by OB stars in star-forming galaxies or active super-massive black holes (AGNs), can ionize the neutral hydrogen gas. The ionizing radiation which escapes into the IGM contributes either to the reionization at z>6 or to keep the environment ionized at lower redshifts. Many studies have confirmed that AGNs cannot provide sufficient ionizing photons so that the star-forming galaxies should be considered as dominant ionizing sources. Galaxies who emit LyC photons (LyC galaxies) can reveal the ionizing sources of the early universe and their properties are related with both inner and outer environment. In this talk, I will first basicly introduce some background of LyC photons and LyC galaxies. Then I will talk about the methods to search LyC galaxies, from imaging to spectroscopic observations, from low redshifts to high redshifts. Also, I will present the properties of LyC galaxies, such as escape fraction, ionizing emissivity and their relation with emission lines. Specifically, as CSST can obtain deep UV imaging and spectroscopic information in large sky area, I will show some results of CSST simulation on detecting this kind of galaxies.
