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Available filters are shown in the table below. An ND filter with OD=1 is assumed to be used for observing in the 9.8-um band to avoid saturation.
| Name | Center wavelength (um) | Band width (FWHM; um) | Note |
| 7.7um | 7.67 | 0.21 | |
| 9.8um+OD1 | 9.61 | 0.96 | OD1 means an ND filter with OD=1 required to avoid saturation. |
| 11.5um | 11.5 | 1.02 | |
| 13.1um | 13.1 | 0.6 | |
| 16.7um | 16.71 | 0.43 | |
| 17.8um | 17.87 | 0.83 | |
| 20.9um | 20.86 | 1.73 | |
| 24.5um | 24.97 | 1.94 |
Saturation limits are calculated as shown in the Table below. The range of values shown for many bands indicates the variable range depending on PWV (assuming 0.3 to 1.5 mm). ND filters with other ODs may be available. By using ND filters or performing defocused observations, objects brighter than the flux densities below, although such observations require special care for calibration.
| Name | Saturation limit |
| 7.7um | 900-1100 Jy |
| 9.8um+OD1 | 2000 Jy |
| 11.5um | 210 Jy |
| 13.1um | 580 Jy |
| 16.7um | 8300-9500 Jy |
| 17.8um | 3000-3500 Jy |
| 20.9um | 1300-1700 Jy |
| 24.5um | 3700-5700 Jy |
Noise-equivalent flux density for one exposure is calculated as shown in the figures below. Corresponding 1-sigma 1-sec sensitivity is also plotted. This calculation assumes aperture photometry with an aperture diameter of 2.5 times the FWHM of the PSF in the medium seeing condition (see here). Since readout noise (assumed 4000e-/read) is the main noise source in short exposures, sensitivity improves with longer exposure times. In the bands at 7.7 um and in the Q band, significant PWV dependency is confirmed. The truncation in the right edge of each band shows the longest exposure time. For accurate subtraction of background emission, it may be better to limit the exposure time for one exposure to less than 0.20 sec.
| &ref(): File not found: "sensitivity_dia_nband.jpg" at page "Observing/mirl_filters_20221225"; | &ref(): File not found: "sensitivity_dia_qband.jpg" at page "Observing/mirl_filters_20221225"; |
| Noise equivalent flux density for one exposure in the N band. Corresponding 1-sigma 1-sec sensitivity is shown by dotted lines. Multiple lines for each filter set show different PWV conditions (from bottom to top, 0.3, 0.5, 0.7, 0.9, 1.2, and 1.5 mm). | Same as the left figure, but for the Q band. |
