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Below we list current FLASH sub-projects and their details.

1) SEAFOG: Studies of eROSITA And FLASH Obscured Galaxies - contact person Vanessa Moss
A project in collaboration with eROSITA, to study the connection between HI absorption and X-ray absorption in AGN. Specifically, we will trace the relationship between N_H and N_HI, and look at the multiwavelength properties of the source population which features either or both of HI/X-ray absorption. Of key interest in this project is understanding the physical relationship between the neutral gas traced by HI absorption and the overall hydrogen content traced by soft X-ray absorption near the central regions of AGN.

Status: Pending observations 


2) Statistically determine evolution of the HI spin temperature - contact person James Allison
Compare the detection yield of intervening HI absorbers in FLASH with that expected from known measurements of f(HI, X) in order to statistically determine how the mean spin temperature in 21-cm absorbers evolves with redshift.  Draw comparisons with direct measurements of the spin temperature using Damped Lyman-alpha absorbers at z > 2 and 21-emission in the Local Group and nearby galaxies. As the survey draws to a close we should have sufficient sight lines to look at relative changes in the detection of 21-cm absorbers across our observed band. 

Status: Pending observations 

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