Extended Data Fig. 2: UV and H i Fit Parameters for New Sight Lines.
From: Diverse metallicities of Fermi bubble clouds indicate dual origins in the disk and halo
The second column represents the allowed velocity range of gas co-rotating with the Milky Way disk in each quasar’s direction67. Xi represents the ion used for metallicity calculations. The UV Voigt fit parameters of Xi for each cloud are the LSR velocity centroid, v0 UV, the Doppler broadening parameter (b-value), and the log column density, log \({N}_{{{{{\rm{X}}}}}^{i}}\). The UV velocity centroid errors include the 7.5 km s−1 COS zero-point uncertainty. The H i Gaussian fit parameters are the LSR velocity centroid, v0 HI, and full-width-half-max, FWHM. For a Gaussian profile, the relation between FWHM and b-value is FWHM=1.665b. The H i log column density, log NHI, is given in the last column. J1853-4158’s H i column was obtained using the spectrum’s rms, as described in the Methods Section. J1919-2958’s H i column was obtained by through the “flip-and-subtract” method (described in the Methods Section) using two velocity ranges for integration, which encompass all potential emission associated with the FB HVC (upper column limit) and emission least affected by stray radiation (lower column limit). J1938-4326’s H i column was obtained using a Gaussian fit to emission. Second and third measurements of the H i column were made by integrating over the C ii absorber’s FWHM and then using Equation (2); see Supplementary Information Section 1 for more details.
