1. Select the Spectra tab from the main menu.

2. Select in the left-hand top subpanel two stars. The left-hand radio button sets the spectrum of the star shown in the top part of the central subpanel. The right-hand radio button sets the spectrum of the star shown in the bottom part of the central subpanel. Note the same star can also be selected for simultaneously viewing different wavelength portions of the spectrum.

3. Select the wavelength region of the spectrum of 30 Å wide in the bottom left-hand subpanel. This wavelength region loads for both stars selected in the top left-hand panel.

4. Press the Load Region #1 button in the top menu of the central subpanel. It displays the spectral regions selected for both stars. Wait a few seconds until the spinner timer vanishes signaling the spectra are fully loaded in the BRASS Spectra Data Interface.

5. The red and blue line labels marked on the wavelength axis can be lifted onto the stellar spectrum by checking the Up radio button and pressing the Shift top labels button next to it.

6. By hovering with the mouse over the red and blue line labels they change color and the BRASS line identification and line rest wavelength are displayed next to the mouse pointer. By clicking the line labels the right-hand subpanel is populated with atomic line data and other spectral line information for the selected star. The line lists increment with new clicks on the line labels. The line lists can be purged by pressing the Clear lines list and Clear graded list button in the right-hand subpanels.

7. The selected wavelength region can be enlarged as is explained in point 7 of the BRASS Help pages: How do I interactively display BRASS stellar spectra? To investigate the atomic data of the BRASS graded lines marked with red labels click on the View data quality link in the right-hand subpanel. This will add a tab to the Atomic Data Quality tab of the central subpanel with additional information. It is also possible to double-click the red line labels. It changes the red line label numbers to L1, L2, … and populates in green color the my list in the right-hand subpanel. The green line list can be saved to the user’s computer disc as is explained in the BRASS Help pages: How do I save a list of graded BRASS lines?

8. Select the Atomic Data Quality tab in the central subpanel and click on the line tab of the selected star to the right-hand side of the Info Page tab. The central panel provides a page with verbose information about the quality assessment results for all atomic line data utilized in the theoretical line profile calculations of BRASS. The top portion of the page informs if the line was Quality assessable marked with Yes or No, and if the line was found to be robust against the analysis method indicated with Yes or No. The page section Cross-matched literature data lists the atomic line data offered in the literature used for the BRASS quality assessments. The table column names are explained in the Info Page.

The page section Line profile plots per G-type benchmark star shows the detailed line profiles observed in the BRASS benchmark stars with black dotted lines. The line plot panels can be interactively modified by checking the boxes or radio-buttons above the line plots. By un/checking the boxes the theoretical line profiles are over-plotted that are calculated in BRASS using the atomic data values listed in the Cross-matched literature data page section. The individual line plots can be zoomed and/or panned with mouse interactions inside each plot panel. The top right-hand menu provides a row of special icons users can activate by mouse-clicking for un/marking the wheel/zooming or panning options with the blue underscore symbol _. The line plots can be reset to the initial plot scale and also be printed to PNG image files for saving to the user’s disc. The top left-hand panel shows the Curve-of-growth (COG in green color) and GRID (in blue color) log(gf)-values vs. Teff-values calculated for each BRASS benchmark star. More information is provided above the line plots.

The page section Quality assessment below the line plots lists important quality assessment information of the atomic line data from all database sources used in BRASS. The page section Equivalent widths provides the equivalent line width values (with the non-Gaussian correction value listed below) measured in the benchmark stars and calculated with the atomic line data provided in the Databases investigated by BRASS also listed in the Cross-matched literature data page section.

9. The Atomic Data Quality tab can be populated with atomic quality assessment data of graded BRASS lines in spectral regions that are loaded for different benchmark stars in any of the four Region # tabs. The View Data Quality links in the top and bottom right-hand subpanels populate the individual line tabs of each benchmark star with a loaded spectral region. The line tabs can be individually removed by clicking x inside a single line tab. The Clear all tab at the top right-hand side removes all activated line tabs.