diff --git a/TrimSPlib.js b/TrimSPlib.js
index 9220187..0a6e2d8 100644
--- a/TrimSPlib.js
+++ b/TrimSPlib.js
@@ -3886,15 +3886,42 @@ function plotProfiles(filenames) {
     win.document.close();
     var plotDiv=win.document.getElementById("newPlot");
 
-    // Extract energies from run files if available
-    var Es = [];
-    for (let i=0;i<filenames.length;i++) {
-	Es[i]=Number(filenames[i].substring(filenames[i].indexOf('_')+2,filenames[i].indexOf('.')));
+    // Build sortable labels from the trailing scan token in each file name.
+    // The old code used the first "_" in the full path, which breaks for
+    // prefixes such as "Au_Cr_Si_3layer_E15000.rge".
+    let plottedFiles = [];
+    for (let i = 0; i < filenames.length; i++) {
+	const filename = Array.isArray(filenames) ? filenames[i] : filenames[i];
+	const baseName = filename.split(/[\\/]/).pop();
+	const stem = baseName.replace(/\.rge$/i, '');
+	const lastUnderscore = stem.lastIndexOf('_');
+	let legend = stem;
+	let sortValue = i;
+
+	if (lastUnderscore !== -1) {
+	    const scanToken = stem.substring(lastUnderscore + 1);
+	    const energyMatch = scanToken.match(/^E(-?\d+(?:\.\d+)?)$/);
+	    if (energyMatch) {
+		const energyEv = Number(energyMatch[1]);
+		legend = 'E=' + (energyEv / 1000) + 'keV';
+		sortValue = energyEv;
+	    } else {
+		legend = scanToken;
+	    }
+	}
+
+	plottedFiles.push({
+	    filename: filename,
+	    legend: legend,
+	    sortValue: sortValue,
+	});
     }
 
+    plottedFiles.sort((a, b) => a.sortValue - b.sortValue);
+
     // loop on sorted values and plot
-    for (let i=0;i<Es.length;i++) {
-	let [cols,data]= readDatFile(filenames[i]);
+    for (let i = 0; i < plottedFiles.length; i++) {
+	let [cols,data]= readDatFile(plottedFiles[i].filename);
 	// convert depth to nm and normalize profile
 	let depth=data[0];
 	let nmuons=data[1];
@@ -3904,7 +3931,7 @@ function plotProfiles(filenames) {
 	    depth[i]=depth[i]/10;
 	    nmuons[i]=nmuons[i]/norm;
 	}
-	Plot_xy(plotDiv,depth,nmuons,['Depth (nm)','Stopped muons (%/nm)','E='+(Es[i]/1000)+'keV']);		
+	Plot_xy(plotDiv,depth,nmuons,['Depth (nm)','Stopped muons (%/nm)',plottedFiles[i].legend]);		
     }
     
 }