UV Photometry Table

These four UV filters have values for PHTFLAM1 set so that their PHTRATIO matches the count ratio of the two detectors (in electrons). The first column lists the quantity, the second column lists the image header keyword name and columns 3 through 6 contain the values for each filter. For UVIS1 fluxes, multiply the UVIS1 count rate by PHOTFLAM. For UVIS2 fluxes, multiply the pipeline value of UVIS2 by PHTFLAM1. Remember to use the appropriate aperture correction for point sources.

Item Header Keyword F200LP F218W F225W F275W
UVIS1 Pivot Wavelength PHOTPLAM 4989.2 2228.8 2373.3 2710.4
UVIS2 Pivot Wavelength PHOTPLAM 4889.2 2224.4 2359.5 2704.0
Count rate ratio, C1/C2 n/a 0.9342 0.7738 0.8110 0.9428
UVIS1 Inverse Sensitivity (S1) PHOTFLAM 4.66567E-20 1.44562E-17 4.51883E-18 3.18585E-18
UVIS2 inverse sensitivity (S2) PHTFLAM2 4.75278E-20 1.12973E-17 3.75053E-18 3.04219E-18
Inverse sensitivity ratio (S2/S1) n/a 1.0187 0.7815 0.8300 0.9549
Adjusted UVIS1 Inverse  Sensitivity (S1’) PHTFLAM1 5.0879E-20 1.4600E-17 4.6248E-18 3.2268E-18
Inverse sensitivity ratio: (S2/S1’) PHTRATIO 0.9341 0.7738 0.8110 0.9428
LAST UPDATED: 05/22/2019

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