diff --git a/beamtime/nappBackground.m b/beamtime/nappBackground.m
index ee6efe5..e8003d8 100644
--- a/beamtime/nappBackground.m
+++ b/beamtime/nappBackground.m
@@ -103,16 +103,16 @@ for ii = 1:size(p.Results.DataTable(p.Results.tableSelection,:),1)
             excludedPoints = excludedata( xData, yData, 'domain',[p.Results.energyStart(1) p.Results.energyEnd(1)] );
             if size(p.Results.energyStart,2) ==2 && size(p.Results.energyEnd,2) ==1
                 excludedPointsEins = excludedPoints;
-                clearvars excludedPoints 
+                clearvars excludedPoints
                 excludedPointsZwei = excludedata( xData, yData, 'domain',[xData(1) p.Results.energyStart(2)] );
                 excludedPoints = excludedPointsEins & excludedPointsZwei;
             elseif size(p.Results.energyStart,2) ==2 && size(p.Results.energyEnd,2) ==2
                 excludedPointsEins = excludedPoints;
-                clearvars excludedPoints 
+                clearvars excludedPoints
                 excludedPointsZwei = excludedata( xData, yData, 'domain',[p.Results.energyStart(2) p.Results.energyEnd(2)] );
                 excludedPoints = excludedPointsEins & excludedPointsZwei;
             end
-            
+
             opts = fitoptions( 'Method', 'NonlinearLeastSquares','Exclude', ~excludedPoints );
             opts.Display = 'Off';
 
@@ -121,8 +121,8 @@ for ii = 1:size(p.Results.DataTable(p.Results.tableSelection,:),1)
             if contains(p.Results.showFigures,'on')
                 % Plot fit with data.
                 figure( 'Name', 'untitled fit 1' );
-               plot( fitresult, xData, yData, excludedPoints );
-               % legend( h, 'y vs. x', 'Excluded y vs. x', 'untitled fit 1', 'Location', 'NorthEast', 'Interpreter', 'none' );
+                plot( fitresult, xData, yData, excludedPoints );
+                % legend( h, 'y vs. x', 'Excluded y vs. x', 'untitled fit 1', 'Location', 'NorthEast', 'Interpreter', 'none' );
                 % Label axes
                 xlabel( 'kinetic energy [eV]', 'Interpreter', 'none' );
                 ylabel( 'PE intensity', 'Interpreter', 'none' );
@@ -131,9 +131,9 @@ for ii = 1:size(p.Results.DataTable(p.Results.tableSelection,:),1)
             end
             if endsWith(p.Results.mode,'divide')
                 tmp{ii,1} = p.Results.DataTable(p.Results.tableSelection,:).(p.Results.tableVariable){ii}./fitresult(p.Results.DataTable(p.Results.tableSelection,:).scientaEkin_eV{ii});
-          
+
             else
-                tmp{ii,1} = p.Results.DataTable(p.Results.tableSelection,:).(p.Results.tableVariable){ii}-fitresult(p.Results.DataTable(p.Results.tableSelection,:).xRayEkin_eV{ii});
+                tmp{ii,1} = p.Results.DataTable(p.Results.tableSelection,:).(p.Results.tableVariable){ii}-fitresult(p.Results.DataTable(p.Results.tableSelection,:).scientaEkin_eV{ii});
             end
         elseif startsWith(p.Results.mode,'mean')
             b_1         = find(p.Results.DataTable(p.Results.tableSelection,:).scientaEkin_eV{ii} >= p.Results.energyStart,1);
@@ -153,7 +153,48 @@ for ii = 1:size(p.Results.DataTable(p.Results.tableSelection,:),1)
         if contains(p.Results.mode,'linfit')
             disp('linfit not yet supported')
             % MEAN
-        else
+
+        elseif contains(p.Results.mode,'exponential')
+            [xData, yData] = prepareCurveData(p.Results.DataTable(p.Results.tableSelection,:).bindingEnergy_eV{ii},p.Results.DataTable(p.Results.tableSelection,:).(p.Results.tableVariable){ii});
+
+            % Set up fittype and options.
+            ft = fittype( 'exp2' );
+            excludedPoints = excludedata( xData, yData, 'domain',[p.Results.energyStart(1) p.Results.energyEnd(1)] );
+            if size(p.Results.energyStart,2) ==2 && size(p.Results.energyEnd,2) ==1
+                excludedPointsEins = excludedPoints;
+                clearvars excludedPoints
+                excludedPointsZwei = excludedata( xData, yData, 'domain',[xData(1) p.Results.energyStart(2)] );
+                excludedPoints = excludedPointsEins & excludedPointsZwei;
+            elseif size(p.Results.energyStart,2) ==2 && size(p.Results.energyEnd,2) ==2
+                excludedPointsEins = excludedPoints;
+                clearvars excludedPoints
+                excludedPointsZwei = excludedata( xData, yData, 'domain',[p.Results.energyStart(2) p.Results.energyEnd(2)] );
+                excludedPoints = excludedPointsEins & excludedPointsZwei;
+            end
+
+            opts = fitoptions( 'Method', 'NonlinearLeastSquares','Exclude', ~excludedPoints );
+            opts.Display = 'Off';
+
+            % Fit model to data.
+            [fitresult, ~] = fit( xData, yData, ft, opts );
+            if contains(p.Results.showFigures,'on')
+                % Plot fit with data.
+                figure( 'Name', 'untitled fit 1' );
+                plot( fitresult, xData, yData, excludedPoints );
+                % legend( h, 'y vs. x', 'Excluded y vs. x', 'untitled fit 1', 'Location', 'NorthEast', 'Interpreter', 'none' );
+                % Label axes
+                xlabel( 'binding energy [eV]', 'Interpreter', 'none' );
+                ylabel( 'PE intensity', 'Interpreter', 'none' );
+                grid on
+                title(p.Results.DataTable(p.Results.tableSelection,:).name{ii},'Interpreter','none')
+            end
+            if endsWith(p.Results.mode,'divide')
+                tmp{ii,1} = p.Results.DataTable(p.Results.tableSelection,:).(p.Results.tableVariable){ii}./fitresult(p.Results.DataTable(p.Results.tableSelection,:).bindingEnergy_eV{ii});
+
+            else
+                tmp{ii,1} = p.Results.DataTable(p.Results.tableSelection,:).(p.Results.tableVariable){ii}-fitresult(p.Results.DataTable(p.Results.tableSelection,:).bindingEnergy_eV{ii});
+            end
+        elseif startsWith(p.Results.mode,'mean')
             b_1         = find(p.Results.DataTable(p.Results.tableSelection,:).bindingEnergy_eV{ii} <= p.Results.energyStart,1);
             b_2         = find(p.Results.DataTable(p.Results.tableSelection,:).bindingEnergy_eV{ii} <= p.Results.energyEnd,1);