Résumé / Abstract Journal-club_Galaxies

Séminaire/Seminar Galaxies

« Preparing for JWST to unveil the sources of cosmic reionization : Connecting gas properties to ionizing photon escape in confirmed LyC leakers and non-leakers »

Floriane Leclercq
Dept. Astron., Univ. Texas Austin (Austin, Texas, Etats-Unis d'Amérique)

Understanding if and how galaxies contributed to reionize the Universe constitutes one of the three principal science goals of the James Webb space telescope. The geometry of the neutral gas in and around galaxies is a key regulator of the escape of ionizing photons. I will present the first statistical study aiming at linking the neutral (as traced by Mg II) and ionized (as traced by [O II]) gas distributions and kinematics to the LyC escape fraction in a sample of 22 confirmed LyC leakers and non-leakers (Leclercq et al. submitted and in prep.). Our observations suggest that strong LyC emitters do not have extended neutral gas halos and ionizing photons may be emitted in many directions. Combined with high ionization diagnostics, we propose the Mg II, and potentially [O II], spatial compactness are indirect indicators of LyC emitting galaxies at high-redshift.

I will also show some preliminary results of our COS/HST programs (PID 17148 and 17153) aiming at linking Lyman alpha and Mg II spectral properties with LyC escape in a large sample of LyC emitters.
jeudi 8 février 2024 - 11:30
Salle des séminaires Évry Schatzman
Institut d'Astrophysique de Paris
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