Questions for SAHARA

Questions for SAHARA:

Can SAHARA address “What happens close to a black hole” using Fe-L line measurements?

What is the actual energy range of the mission? A range of 0.2-3 keV is stated, but then there is some discussion of the Fe K lines, and the effective area curve shows significant area there. But there are statements that the 6-7 keV range isn’t required. Is there some limitation of the instrument design that precludes using those photons?

Unlike the Fe K lines, the Fe L lines form a complex of many closely spaced lines, some of which are also close in energy to Ne lines. Please explain how the expected velocity shifts due to strong gravity effects compare to the line spacing, and demonstrate that line confusion will not make the use of Fe L lines for this purpose impractical. Will you need the K line measurements as well as L lines to decipher what is going on?

For the SMBH growth SAHARA will not measure black hole spin, but will search for and measure AGN winds in ~ 500 serendipitous sources / year. How will this measurement answer the question of how supermassive black holes grow and how does it compare to spin measurements?

Please clarify what velocities are expected in AGN outflows and what the requirement is for resolving velocity structure (in km/s).

Please clarify what turbulent velocities are expected in the clusters and what the requirement is for resolving velocity structure (in km/s). Is the energy resolution in the outer regions of the calorimeter array (4 eV) adequate?

In the large-scale structure question there is no mention of WHIM measurements.Is this because the spectral resolution is not adequate?

For measuring the metallicity and velocity (connection between SMBH formation and large scale structure) how important are the FeK lines? (SAHARA has very little effective area above 2 keV.)

Please show a histogram of energy resolution from existing arrays of TES (with and without hydra design).