Simulated Intensity Maps from SPHEREx Mission During Cosmic Reionization
Researchers have simulated emission line intensity maps observable by the SPHEREx space telescope during the cosmic reionization epoch, including Lyman-alpha, hydrogen, and oxygen emission lines with radiative transfer modeling. The simulations incorporate multiple emission sources and dust extinction effects based on observations of high-redshift galaxies. These simulations are important for planning SPHEREx observations and understanding the feasibility of detecting reionization-era structures with current and future instruments.
A new study presents detailed simulations of intensity maps from five emission lines—Lyman-alpha, H-alpha, H-beta, [OII], and [OIII]—that the SPHEREx space telescope is expected to observe during cosmic reionization (z~6 and beyond). The simulations include radiative transfer calculations for Lyman-alpha and incorporate realistic dust extinction models derived from observations of high-redshift galaxies. The research demonstrates that detecting certain features during reionization with SPHEREx will be challenging and may require more sensitive instruments like the proposed Cosmic Dawn Intensity Mapper. This work provides crucial predictions for SPHEREx's science capabilities and helps guide the design of future observatories aimed at studying this critical epoch in cosmic history.
What's missing
The study's own limitations and caveats are not detailed in the provided abstract excerpt, including assumptions about the dust extinction model, the range of galaxy properties included in simulations, and specific sensitivity thresholds assumed for SPHEREx.
What different sources said
- arXiv astro-phCenter
On Cross-Correlating Line Intensity Maps from SPHEREx during Reionization
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