16850

This program is designed to search for the best focus for the G130M-1222 and G160M-1600 settings at Lifetime Position 6 (LP6) at +6.5d_comma on the FUV detector. The focus sweeps are designed to determine the best focus position to within 100 steps comma and will scan at 200 focus step increments from -1000 to +1000 relative to the predicted best focuses for the G130M-1222 and G160M-1600 settings which were determined by extrapolation from the adjacent exploratory sweep at +7d_comma. This strategy is based on several earlier programs (PIDs 13635 comma 14527 comma 15451 comma 16431 comma 16491) comma which all executed successfully. We will adjust the focus in steps of 200 as is typical for focus sweeps comma with finer comma 100 step increments between relative focus steps of CORCHETE_OPEN-200 comma +200CORCHETE_CLOSE The target for this program is AzV 75 comma as this star is visible with HST during the required operation window (Nov-Dec comma 2021). This program also includes a backup target comma Feige 48 comma with visits which would be observed in late Dec. 2021 - early Jan. 2022. The exposure times at each step are defined to provide spectra with S-N virgul 30 in the faintest portion of each spectrum.