Understanding when and how reionization happened is crucial for studying the early structure formation and the properties of the first galaxies in the Universe. At
JWST observations have recently begun delivering the first samples of Ly
- PAR ID:
- 10535498
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 972
- Issue:
- 1
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 56
- Size(s):
- Article No. 56
- Sponsoring Org:
- National Science Foundation
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Abstract z > 5.5, the observed intergalactic medium (IGM) optical depth shows a significant scatter, indicating an inhomogeneous reionization process. However, the nature of the inhomogeneous reionization remains debated. A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE) is a JWST Cycle 1 program that has spectroscopically identified >400 [Oiii ] emitters in 25 quasar fields atz > 6.5. Combined with deep ground-based optical spectroscopy of ASPIRE quasars, the ASPIRE program provides the current largest sample for IGM-galaxy connection studies during cosmic reionization. We present the first results of IGM effective optical depth measurements around [Oiii ] emitters using 14 ASPIRE quasar fields. We find the IGM transmission is tightly related to reionization era galaxies to the extent that a significant excess of Lyα transmission exists around [Oiii ] emitters. We measure the stacked IGM effective optical depth of IGM patches associated with [Oiii ] emitters and find they reach the same IGM effective optical depth at leastd z ∼ 0.1 ahead of those IGM patches where no [Oiii ] emitters are detected, supporting earlier reionization around [Oiii ] emitters. Our results indicate an enhancement in IGM Lyα transmission around [Oiii ] emitters at scales beyond 25h −1cMpc, consistent with the predicted topology of reionization from fluctuating UV background models. -
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