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Table 1.
Lower and upper bounds placed on initial conditions in the line-fitting routine.
| Fit parameters | Boundary conditions |
|---|---|
| Gaussian (for emission): | |
| Line centre, λ0 (Å) | Δλ0 = 0.3 |
| Line flux, F (erg s−1 cm−2) | F ≥ 0 |
| Line width, σλ (Å) | σλ > 0 |
| Voigt (for absorption): | |
| Redshift, z: | |
| Lyα | Δz1 ≤ 5.0 × 10−3 |
| Δz2 ≤ 1.0 × 10−3 | |
| Δz3 ≤ 4.0 × 10−3 | |
| Δz4 ≤ 3.0 × 10−3 | |
| C IV | Δzn ≤ 6.0 × 10−4 |
| Si IV and N V | Δzn ≤ 6.0 × 10−3 |
| Doppler parameter, b (km s−1): | |
| Lyα, C IV, N V, and Si IV | 40 ≤ b ≤ 400 |
| Column density, N (cm−2): | |
| Lyα | 1012 ≤ N ≤ 1020 |
| C IV, N V, and Si IV | 1013 ≤N≤ 1016 |
Notes. Δ is the largest permissible deviation (from the initial guess) imposed on a fit parameter.
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