Details

Autor(en) / Beteiligte

• Jung, Intae
• Papovich, Casey
• Finkelstein, Steven L
• Simons, Raymond C
• Estrada-Carpenter, Vincente
• Backhaus, Bren E
• Cleri, Nikko J
• Finlator, Kristian
• Giavalisco, Mauro
• Ji, Zhiyuan
• Matharu, Jasleen
• Momcheva, Ivelina
• Straughn, Amber N
• Trump, Jonathan R

Titel

CLEAR: Boosted Ly alpha Transmission of the Intergalactic Medium in UV-bright Galaxies

Ist Teil von

• The Astrophysical journal, 2022-07, Vol.933 (1)

Ort / Verlag

Goddard Space Flight Center: IOP Science

Erscheinungsjahr

2022

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Reionization is an inhomogeneous process, thought to begin in small ionized bubbles of the intergalacticmedium (IGM) around overdense regions of galaxies. Recent Lyman-alpha (Lyα) studies during the epochof reionization show growing evidence that ionized bubbles formed earlier around brighter galaxies, suggest-ing higher IGM transmission of Lyαfrom these galaxies. We investigate this problem using IR slitless spec-troscopy from the Hubble Space Telescope (HST) Wide-Field Camera 3 (WFC3) G102 grism observations of148 galaxies selected via photometric redshifts at6.0< z <8.2. These galaxies have spectra extracted fromthe CANDELS LyαEmission at Reionization (CLEAR) survey. We combine the CLEAR data for 275 galaxieswith the Keck/DEIMOS+MOSFIRE dataset from the Texas Spectroscopic Search for LyαEmission at the Endof Reionization Survey. We then constrain the Lyαequivalent-width (EW) distribution at6.0< z <8.2, whichis described by an exponential form,dN/dEW∝exp(-EW)/W0, with the characteristice-folding scale width(W0). We confirm a significant drop of the Lyαstrength (orW0) atz >6. Furthermore, we compare the redshiftevolution ofW0between galaxies at different UV luminosities. The UV-bright (MUV<−21, orLUV> L∗)galaxies show weaker evolution with a decrease of 0.4 (±0.2) dex inW0atz >6while UV-faint (MUV>−21,orLUV< L∗) galaxies exhibit a significant drop by a factor of 0.7-0.8 (±0.2) dex inW0fromz 6.Our results add to the accumulating evidence that UV-bright galaxies exhibit boosted Lyαtransmission in theIGM, suggesting that reionization completes sooner in regions proximate to galaxies of higher UV luminosity.