…

                                                                                                                   4
                                                               60                                               5 10

                                                               55
                                                                                                                   4
                                                                                                                4 10
                                                               50




                                                                     PHD FWHM (%) (²)
2 107                                                          45                                                  4
                                                                                                                3 10




                                                                                                       Counts
                                                               40
   Gain (o)




                                                                                                                   4
                                                               35                                               2 10

                                                               30                                                  4
                                                                                                                1 10
                                                               25

     107                               20                                                                          0
                                                                                                                                  6           7         7         7              7      7
      4200 4300 4400 4500 4600 4700 4800                                                                               0       5 10    1 10 1.5 10 2 10 2.5 10 3 10
                                     Detector Voltage                                                                                              Gain
                          Figure 8. Gain and PHD as a function of voltage                                              Figure 9. PHD for FL03B, UV (2537Å)
                                 for FL03B, UV (2537Å) full flood.                                                            full flood (32% FWHM).
                                                                                                                   4
                        0.5                                                                               3 10

                                                                                                                       4
                                                                                                 2.5 10
cm )




                        0.4
-2




                                                                                   Output Event Rate




                                                                                                                   4
                                                                                                          2 10
-1




                        0.3
 Background rate (sec




                                                                                                                       4
                                                                                                 1.5 10
                        0.2                                                                                        4
                                                                                                          1 10

                        0.1                                                                                        3
                                                                                                          5 10

                                                                                                                   0
                         0                                                                                0 10
                                                                                                                           0           4           4          4              4              4
                              0    50       100         150    200                                            0 10              1 10        2 10       3 10           4 10           5 10
                                  Threshold (% modal gain)                                                                                 Input Event Rate
                        Figure 10. FL02 background rate as a                                                     Figure 11. Flight electronics dead time curve
                           function of counting threshold.                                                          comparing the output/input event rate




                         Figure 12. Pinhole mask image for FL02, 8.6cm x 1cm with 1mm pinhole period, 10µm holes.