Galaxy Spectral Lines Interactive Reference
JWST NIRCam spectroscopy reference for galaxy observations at any redshift
with WFSS at 3.1-5.0 μm through the F356W and F444W filters with grisms
📡 Observed Wavelength Positions & JWST Coverage
Observable Lines
🔴 Emission Lines
Hydrogen Series
Balmer Series (n→2)
| Line | Rest λ (Å) | Obs λ (μm) | Rel. Flux | JWST |
|---|---|---|---|---|
| Hα | 6564.614 | 3.28 | 1.00 | ✓ |
| Hβ | 4862.721 | 2.43 | 0.35 | ✗ |
| Hγ | 4341.68 | 2.17 | 0.17 | ✗ |
| Hδ | 4102.89 | 2.05 | 0.10 | ✗ |
Paschen Series (n→3) - Infrared
| Line | Rest λ (Å) | Obs λ (μm) | Transition | JWST |
|---|---|---|---|---|
| Pa α | 18756.0 | 9.38 | n=4→3 | ✗ |
| Pa β | 12821.6 | 6.41 | n=5→3 | ✗ |
| Pa γ | 10941.1 | 5.47 | n=6→3 | ✗ |
| Pa δ | 10052.1 | 5.03 | n=7→3 | ✗ |
Brackett Series (n→4) - Far-Infrared
| Line | Rest λ (Å) | Obs λ (μm) | Transition | JWST |
|---|---|---|---|---|
| Br α | 40522.8 | 20.26 | n=5→4 | ✗ |
| Br β | 26258.7 | 13.13 | n=6→4 | ✗ |
| Br γ | 21661.2 | 10.83 | n=7→4 | ✗ |
Oxygen Forbidden Lines
| Line | Rest λ (Å) | Obs λ (μm) | Flux Ratio | JWST |
|---|---|---|---|---|
| [OII]λ3727 | 3727.092 | 1.86 | Doublet | ✗ |
| [OIII]λ4959 | 4960.295 | 2.48 | 1:3 | ✗ |
| [OIII]λ5007 | 5008.239 | 2.50 | 3:1 | ✗ |
Nitrogen & Sulfur Lines
| Line | Rest λ (Å) | Obs λ (μm) | Notes | JWST |
|---|---|---|---|---|
| [NII]λ6549 | 6549.86 | 3.27 | Weaker NII | ✓ |
| [NII]λ6584 | 6585.27 | 3.29 | Stronger NII | ✓ |
| [SII]λ6718 | 6718.29 | 3.36 | Density diag | ✓ |
| [SII]λ6732 | 6732.68 | 3.37 | Density diag | ✓ |
High Ionization Lines
| Line | Rest λ (Å) | Obs λ (μm) | Type | JWST |
|---|---|---|---|---|
| Lyα | 1215.24 | 0.61 | Often absorbed | ✗ |
| C IV | 1549.48 | 0.77 | High ionization | ✗ |
| C III] | 1908.734 | 0.95 | Semi-forbidden | ✗ |
| Mg II | 2799.117 | 1.40 | AGN diagnostic | ✗ |
🔵 Stellar Absorption Lines
Strong Stellar Features
| Line | Rest λ (Å) | Obs λ (μm) | Diagnostic | JWST |
|---|---|---|---|---|
| Ca II K | 3934.777 | 1.97 | Age indicator | ✗ |
| Ca II H | 3969.588 | 1.98 | Age indicator | ✗ |
| G-band | 4305.61 | 2.15 | CH molecular | ✗ |
| Mg I b | 5176.7 | 2.59 | Metallicity | ✗ |
| Na I D | 5895.6 | 2.95 | Interstellar | ✗ |
| Ca II λ8500 | 8500.36 | 4.25 | NIR triplet | ✓ |
| Ca II λ8544 | 8544.44 | 4.27 | NIR triplet | ✓ |
| Ca II λ8664 | 8664.52 | 4.33 | NIR triplet | ✓ |
🛰️ JWST NIRCam Grism Specifications
F356W Grism: λ = 3.0 - 4.0 μm, R ~ 1600, optimal for z = 4-6 Hα, [OIII], [SII] observations
F444W Grism: λ = 3.8 - 5.0 μm, R ~ 1600, optimal for z = 5-7 Hα, higher-z [OIII] observations
Observing Strategy: Use both grisms for optimal line coverage across different redshift ranges
📋 Selected Line Details
Click on any line in the tables above to see detailed information and observability.
Created by: Ronaldo Laishram
© 2025 Ronaldo Laishram | www.ronaldolaishram.com
Galaxy Spectral Lines Interactive Reference for JWST NIRCam Observations