calculate+redshift

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Finding the Redshift

First off find two very strong emission lines. Then find the ratio between the two. (divide the bigger wavelength by the smaller one) Check to make sure it is a legitimate ratio from a table of emission line ratios. Use the redshift equation and solve for z. Confirm with other ratios and wavelengths. Watch out for wavelengths close to the telluric bands because they are strong absorption lines and will mess up the reading.

Table of wavelengths: Values of Critical density: __Identification__ **__Wavelength (Å)__** __log //Ncr// (cm-3)__ [C III] **1909** 9.0 [O II] **3726.1** 3.5 [O II] **3728.8** 2.8 [Fe VII] **3760.3** 7.6 [Ne III] **3868.8** 7.0 [Ne III] **3967.5** 7.0 [S II] **4068.6** 6.4 [O III] **4363.2** 7.5 [Ar IV] **4711.3** 4.4 [Ar IV] **4740.0** 5.6 [O III] **5006.9** 5.8 [Fe VIII] **5159.0** 6.5 [Fe VI] **5176.4** 7.6 [Fe VII] **5721.1** 7.6 [N II] **5754.6** 7.5 [Fe VII] **6086.9** 7.6 [O I] **6300.3** 6.3 [S III] **6312.1** 7.2 [Fe X] **6374.6** 9.7 [N II] **6583.4** 4.9 [N I] **5197.9** 3.3 [S II] **6716.4** 3.2 [S II] **6730.8** 3.6 [Ar III] **7135.4** 6.7 [O II] **7319.9** 6.8 [O II] **7330.2** 6.8 [|source]