Work

What causes the ultraviolet extinction bump at the cosmic dawn?

Year: 2024

Type: article

Abstract: ABSTRACT The enigmatic ultraviolet (UV) extinction bump at 2175 $\, {\rm \mathring{\rm A}}$, the strongest spectroscopic absorption feature superimposed on the interstellar extinction curve, has recently been detected at the cosmic dawn by the JWST in JADES-GS-z6-0, a distant galaxy at redshift $z\approx 6.71$, corresponding to a cosmic age of just 800 million years after the big bang. Although small graphite grains have historically long been suggested as the carrier of the 2175 $\, {\rm \mathring{\rm A}}$ extinction bump and graphite grains are expected to have already been pervasive in the early Universe, in this work we demonstrate that small graphite grains are not responsible for the UV extinction bump seen at the cosmic dawn in JADES-GS-z6-0, as the extinction bump arising from small graphite grains is too broad and peaks at wavelengths that are too short to be consistent with what is seen in JADES-GS-z6-0.

Source: Monthly Notices of the Royal Astronomical Society Letters

DOI: 10.1093/mnrasl/slae095

Authors: Qi Li, X J Yang, Aigen Li

Institutions: Xiangtan University, University of Missouri

Language: English

Topic: Astrophysics and Star Formation Studies

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $1,434

Funder: National Natural Science Foundation of China