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 |