Detector | Dark Current (Amps) | Dark Flux (W/cm^2/um) | Flux Density (Jy) |
0 | 4.96e-16 | 5.01e-18 | 36.6 |
1 | 2.08e-16 | 4.07e-18 | 44.1 |
2 | 2.20e-16 | 3.34e-18 | 45.4 |
3 | 1.18e-16 | 2.07e-18 | 38.7 |
4 | 1.56e-16 | 3.03e-18 | 72.9 |
5 | 2.50e-16 | 7.92e-19 | 25.2 |
6 | 7.30e-18 | 7.47e-21 | 0.34 |
7 | 5.31e-17 | 2.04e-20 | 1.30 |
8 | 1.76e-16 | 9.30e-20 | 7.67 |
9 | 1.21e-16 | 3.77e-19 | 40.5 |
2. The LWS is calibrated on a point source (Uranus). The optical design of the LWS has a complex mirror M2 inclined to the primary mirror and incoming light. The substrate supporting M2 appears to be reflective, especially at longer wavelengths which may explain the off-axis fringing seen in extended sources. For extended sources larger than the average LWS beam (75"), an extended source correction must be applied to the data. This correction adjusts the point source fluxes for additional off-axis contributions to the source flux. These corrections have been derived under the ideal assumption that the source is smooth with a very extended flux distribution which may not be the case if the observations contain structure or embedded sources. The extended source correction has been tested on the Trumpler 14 and 16 extended source fields and compared to IRAS 100 micron fluxes. The LWS/IRAS ratio was about 0.9 +/- 0.2. For a more detailed explanation of this correction, please see the LWS Handbook. This table gives the approximate effective radius, effective solid angle (omega x 10^6), and correction of the beam for each detector. The corrected source flux for an observed flux F (Jy), is S = F * (correction) / (omega x 10^6) MJy/sr
Detector | Effective Beam Radius (") |
omega x 10^6 (sr) | Correction |
0 | 39 | 0.114 | 0.88 |
1 | 42 | 0.130 | 0.88 |
2 | 43 | 0.135 | 0.84 |
3 | 41 | 0.117 | 0.73 |
4 | 40 | 0.114 | 0.70 |
5 | 38 | 0.107 | 0.69 |
6 | 39 | 0.111 | 0.69 |
7 | 35 | 0.092 | 0.62 |
8 | 34 | 0.088 | 0.55 |
9 | 33 | 0.083 | 0.48 |