Upload any IUE SWP spectrum as a plain .txt file with two whitespace-separated columns: wavelength (Å) and flux.
Demo loads Spectrum 70 — a real 3C273 archival observation — so you can explore the pipeline without your own file.
Once submitted, the pipeline fits a power-law continuum, searches 5,600 Gaussian candidate models, refines with scipy, and returns all line statistics instantly.
Δλ — wavelength shift from rest frame. Velocity — Doppler offset in km/s (v = cΔλ/λ_rest).
FWHM — full width at half maximum, converted to km/s via 2.355σ·c/μ.
Flux — integrated line flux A·σ·√(2π). EW — equivalent width relative to continuum.
SNR — detection significance = Flux / σ_Flux. χ²red — reduced chi-squared goodness of fit.
Click a row's line tab to inspect its zoomed fit and full diagnostics.
| Line | Rest λ (Å) | Fitted λ (Å) | Δλ (Å) | Velocity (km/s) | σ (Å) | FWHM (km/s) | Flux | Flux Err | EW (Å) | EW Err | SNR | χ²red | Status |
|---|
Amplitude — peak flux density of the Gaussian above continuum.
Line Center — fitted wavelength μ of the emission peak (Å).
Wing Window — full integration width W used for flux/EW. Blue wing = μ−W/2, Red wing = μ+W/2.
Sigma — Gaussian width σ in Å. FWHM = 2.355σ.
| Amplitude | |
| Line Center (Å) | |
| Wing Window (Å) | |
| Min Wavelength (Å) | |
| Max Wavelength (Å) | |
| Sigma (Å) |
| Rest Wavelength (λ_rest) | 1216.00 Å |
| Fitted Center (μ) | 1214.97 Å |
| Wavelength Offset (Δλ) | -1.03 Å |
| Velocity Offset (v) | -254.1 km/s |
| Gaussian Amplitude (A) | 8.00e-13 |
| Gaussian Sigma (σ) | 6.14 Å |
| FWHM (Å) = 2.355σ | 14.13 Å |
| FWHM (km/s) | — km/s |
| Derived 2.355σ FWHM | 14.13 Å |
| Integrated Line Flux | — |
| Flux Error | — |
| Equivalent Width (EW) | — Å |
| EW Error | — Å |
| Signal-to-Noise (SNR) | — |
| Reduced χ² (χ²red) | 0.036 |
| Fitting Wing Window | 19.0 Å |