feat(fit): add --fix-e0 flag

numass-workspace/src/main/kotlin/ru/inr/mass/scripts/application.kt

@@ -34,6 +34,7 @@ data class FitCustomParams(
     val fixTrap: Boolean = false,
     val trapFunc: String = "TrapInterpolator",
     val fixRWall: Boolean = false,
+    val fixE0: Boolean = false,
     val wallFunc: String = "wallStep",
     val noAdiabacity: Boolean = false,
     val adiabacityFunc: String = "2024_11"
@@ -94,6 +95,7 @@ fun main (args: Array<String>) {
             fixTrap =  config.fixTrap,
             trapFunc = trapFunc,
             fixRwall = config.fixRWall,
+            fixE0 = config.fixE0,
             wallFunc = wallFunc,
             noAdiabacity = config.noAdiabacity,
             adiabacityFunc = adiabacityFunc

numass-workspace/src/main/kotlin/ru/inr/mass/scripts/fit-custom.kt

@@ -101,6 +101,8 @@ class CustomArgs : CliktCommand() {
 
     val noAdiabacity: Boolean by option().flag().help("Use const 1 instead of adiabacity function")
 
+    val fixE0: Boolean by option().flag().help("Don't fit e0 variable")
+
     // TODO: convert to enum
     val adiabacityFunc: String by option().default("2024_11").help(
         "adiabacity type (one of 2024_11, shifted, vasya)"
@@ -130,6 +132,7 @@ class CustomArgs : CliktCommand() {
                 fixBkg,
                 fixU2,
                 fixTrap,
+                fixE0,
                 getTrapByName(trapFunc),
                 fixRwall,
                 noAdiabacity,
@@ -172,6 +175,7 @@ suspend fun processCustom(
     fixBkg: Boolean,
     fixU2: Boolean,
     fixTrap: Boolean,
+    fixE0: Boolean,
     trapFunc: ITrap,
     fixRwall: Boolean,
     noAdiabacity: Boolean,
@@ -211,7 +215,6 @@ suspend fun processCustom(
     }
 
     val fitVars = mutableListOf(
-        NumassBeta.e0,
         NBkgSpectrum.norm,
 //        NBkgSpectrum.bkg,
 //        rearWall,
@@ -221,6 +224,10 @@ suspend fun processCustom(
 //        NumassTransmission.trap,
     )
 
+    if (!fixE0) {
+        fitVars += NumassBeta.e0
+    }
+
     if (!fixBkg) {
         fitVars += NBkgSpectrum.bkg
     }