We intend to use a model atmosphere for the DB white dwarf WD0308-565 to calibrate COS below 1150 Ang. This model has been vetted at longer wavelengths, where it has been shown to agree with previous DA calibrations. However, unlike the DA standards, WD0309-565 contains very little hydrogen. This eliminates uncertainties in the physics of the Lyman stark wings which affect virtually all wavelengths below 1100 Ang. As a result, it will provide a superior, less biased calibration for COS at these wavelengths. These same data will be used to produce fixed pattern templates for the new COS FUV settings. These can be used to reduce the effects of the COS fixed pattern noise. We used the available STIS and FUSE spectra of WD0308-565 for the ETC calculations (COS.sp.490029 for CENWAVE 1055 and COS.sp.490065 for CENWAVE 1096). The exposure times are set by the counts on segment B (FUVB), since its wavelength coverage is short ward of the MgF2 cut off, where the COS response drops by a factor of 100. The ETC calculations show that in a 50 min. orbit, the count rate over the FUVB is relatively uniform at roughly 250 counts/resel/s = 0.0028/counts/pixel/s. Further, for 1055 and 1096 settings, the FUVB has a plate scale of ' 0:01A/pixel. Using these numbers, we see that we can achieve our primary goal of a S/N = 50/1 over 1A bins with four 50 min. orbits (one at each FPPOS) for each CENWAVE. These will give a S/N of 58/1/A. The goals of this proposal are straightforward: To produce a better FUV fux calibration for the COS FUV settings which is free of uncertainties due to Stark broadening of the Lyman lines and to develop a P-flat that will greatly enhance the data quality of all COS FUV data. Upon its completion, we will furnish STScI with sensitivity curves for the COS FUV CENWAVE 1055 and 1096 settings derived from the best available model atmosphere for the DB WD0308-565. We will also provide P-ats for these CENWAVEs. Because the P-flat is a 1-D correction for an inherently 2-D effect, a new P-flat must be determined for the FUV settings since they fall at a different cross-dispersion location on the detector than the traditional settings. The same observations used to derive the absolute fux calibration can be used to derive the P-ats as well, if adequate S/N is achieved. HOT STARS 0 true true false false false SUPPORTED CALIBRATION PHOTOMETRIC Coordinate information same as Prop 12795 J2000 J2000 COS/NUV Imaging No No MIRRORA COS/FUV Spectroscopic No No G130M 1055 COS/FUV Spectroscopic No No G130M 1096 Timing link suitability includes constraints ([Group (01 02) Within 7.0 days]) The scheduling data was generated by CASM 21.2. CASM was run in Phase II mode. 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CASM was run in Phase II mode. (Tic-Visit :proposal-id 13353 :visit-id "02" :proposal-version -1 :trans-version "20130502" :date "13-Aug-2013 13:10:16.0" :trans-errors '(:WARNINGS 1 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 1278640 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13353 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13353 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2827 :al-overhead-at-end 0 :internal-dur-at-end 67 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3491 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13353 :visit-id "02" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2964 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3491 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13353 :visit-id "02" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2964 :al-overhead-at-end 0 :internal-dur-at-end 48 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3491 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13353 :visit-id "02" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2964 :al-overhead-at-end 0 :internal-dur-at-end 376 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3491 :pcs-gap 0 ) true 4 0