Plot Tab

The Plot tab provides a built-in plotting utility for visualizing cross sections, S-factors, and calculation results. This tab requires the QWT library to be enabled at compile time (-DUSE_QWT=ON).

Note

The built-in plotter is intended as a quick visualization tool during analysis. For publication-quality figures, use the output files (AZUREOut_aa=*_R=*.out and AZUREOut_aa=*_R=*.extrap) with an external plotting program.

Selecting Segments

The tab displays two lists of segments, corresponding to the segments defined in the Segments tab:

  • Segments From Data – data-driven calculation segments.

  • Segments Without Data – pure calculation segments.

Click a segment to select it (the background color changes). Click again to deselect. Multiple segments can be selected simultaneously.

Drawing Plots

After selecting one or more segments, click the Draw button in the lower-left corner to render the plot.

  • R-matrix calculations are shown as red lines.

  • Data points are shown in black with different marker shapes for different segments.

Axis Configuration

X-Axis

Choose the horizontal axis quantity:

  • CoM Energy – center-of-mass energy

  • Excitation Energy – excitation energy of the compound nucleus

  • CoM Angle – center-of-mass angle

Y-Axis

Choose the vertical axis quantity:

  • Cross Section – cross section (barns or barns/sr)

  • S-Factor – astrophysical S-factor (MeV b or MeV b/sr)

Both axes have a Log checkbox to switch to logarithmic scale.

Note

Drawing an analyzing-power segment switches the y-axis to a linear Cross Section scale automatically, overriding both settings. This is a necessity rather than a preference: \(A_y\) is a dimensionless ratio that is negative over much of its range, so a logarithmic axis cannot represent it and an S-factor conversion has no meaning for it. Negative points are drawn; for every other observable the non-positive values that a logarithmic axis cannot show are still filtered out.

Tip

Plotting with Excitation Energy on the x-axis is very useful for comparing data from different entrance and exit particle channels, since all channels share the same excitation energy scale.

Interacting with Plots

Zoom in

Click and hold the left mouse button, then drag to highlight a region.

Zoom out

Right-click anywhere on the plot.

Pan

Hold the center mouse button and drag to shift the view.

When first plotted, axes are automatically scaled to fit all data.

Exporting and Printing

Export…

Save the current plot to an image file. Most standard image formats are supported.

Print…

Send the current plot to a printer.

Both export and print use the currently displayed view, so you can zoom in before exporting to customize the plotted area.