모바일 메뉴 닫기
 

최신연구

제목
LyC escape from SPHINX galaxies in the Epoch of Reionization
작성일
2022.08.17
작성자
천문우주학과
게시글 내용

LyC escape from SPHINX galaxies in the Epoch of Reionization


Joakim Rosdahl, Jérémy Blaizot, Harley Katz, Taysun Kimm, Thibault Garel, Martin Haehnelt, Laura C. Keating, Sergion Martin-Alvarez, Léo Michel-Dansac, Pierre Ocvirk


We measure escape fractions, fesc, of ionizing radiation from galaxies in the SPHINX suite of cosmological radiation-hydrodynamical simulations of reionization, resolving halos with Mvir7.5×107 M with a minimum cell width of 10 pc. Our new and largest 20 co-moving Mpc wide volume contains tens of thousands of star-forming galaxies with halo masses up to a few times 1011 M. The simulated galaxies agree well with observational constraints of the UV luminosity function in the Epoch of Reionization. The escape fraction fluctuates strongly in individual galaxies over timescales of a few Myrs, due to its regulation by supernova and radiation feedback, and at any given time a tiny fraction of star-forming galaxies emits a large fraction of the ionizing radiation escaping into the inter-galactic medium. Statistically, fesc peaks in intermediate-mass, intermediate-brightness, and low-metallicity galaxies (M107 M, M150017, Z5×103 Z), dropping strongly for lower and higher masses, brighter and dimmer galaxies, and more metal-rich galaxies. The escape fraction correlates positively with both the short-term and long-term specific star formation rate. According to SPHINX, galaxies too dim to be yet observed, with M150017, provide about 55 percent of the photons contributing to reionization. The global averaged fesc naturally decreases with decreasing redshift, as predicted by UV background models and low-redshift observations. This evolution is driven by decreasing specific star formation rates over cosmic time.


https://arxiv.org/abs/2207.03232

저자명
Taysun Kimm