Add BRF / beam jitter to the MC

UserTools/AssignBunchTimingMC/AssignBunchTimingMC.cpp

@@ -15,6 +15,7 @@ bool AssignBunchTimingMC::Initialise(std::string configfile, DataModel &data){
     bool got_width     = m_variables.Get("bunchwidth", fbunchwidth);
     bool got_interval  = m_variables.Get("bunchinterval", fbunchinterval);
     bool got_count     = m_variables.Get("bunchcount", fbunchcount);
+    bool got_BRF       = m_variables.Get("BRFfituncertainty", fBRF);
     bool got_sample    = m_variables.Get("sampletype", fsample);
     bool got_trigger   = m_variables.Get("prompttriggertime", ftriggertime);
     bool got_waveform  = m_variables.Get("PMTWaveformSim", fPMTWaveformSim);
@@ -49,6 +50,15 @@ bool AssignBunchTimingMC::Initialise(std::string configfile, DataModel &data){
         Log(logmessage, v_warning, verbosity);
     }
 
+    // Uncertainty due to beam signals / electronic jitter in our system
+    // see https://annie-docdb.fnal.gov/cgi-bin/sso/ShowDocument?docid=6489 for more information
+    if (!got_BRF) {
+        fBRF = 0;
+        logmessage = ("Warning (AssignBunchTimingMC): \"BRFfituncertainty\" not "
+            "set in the config file. Using default: 0ns (no uncertainty will be included for this)");
+        Log(logmessage, v_warning, verbosity);
+    }
+
     if (!got_sample) {
         fsample = 0;    // assume they are using the Tank samples
         logmessage = ("Warning (AssignBunchTimingMC): \"sampletype\" not "
@@ -78,6 +88,7 @@ bool AssignBunchTimingMC::Initialise(std::string configfile, DataModel &data){
         std::cout<<"bunch width       = "<<fbunchwidth<<" ns"<<"\n";
         std::cout<<"bunch interval    = "<<fbunchinterval<<" ns"<<"\n";
         std::cout<<"number of bunches = "<<fbunchcount<<"\n";
+        std::cout<<"BRF uncertainty   = "<<fBRF<<"\n";
         std::cout<<"PMTWaveformSim    = "<<fPMTWaveformSim<<"\n";
         std::cout<<"sample type       = "<<(fsample == 0 ? "(0) Tank" : "(1) World")<<"\n";
         std::cout<<"trigger time      = "<<(ftriggertime == 0 ? "(0) prompt trigger starts when first particle arrives (default WCSim)" 
@@ -206,6 +217,9 @@ bool AssignBunchTimingMC::LoadStores()
 
 void AssignBunchTimingMC::BNBtiming()
 {
+
+    // Add instrinsic bunch width and the jitter from our beam signals / fitting
+
     // Determined from GENIE samples (as of Dec 2024)
     const double tank_time = 33.0;    // Tank neutrino arrival time: 33ns
     const double world_time = 33.0;   // WORLD neutrino arrival time: 33ns
@@ -229,9 +243,17 @@ void AssignBunchTimingMC::BNBtiming()
     std::normal_distribution<double> distribution(0, fbunchwidth); 
     jitter = distribution(generator);
 
+    // assign beam jitter (BRF uncertainty)
+    std::normal_distribution<double> BRF_distribution(0, fBRF);
+    BRF_jitter = BRF_distribution(generator);
+
     if (verbosity >= v_message) {
-        std::string logmessage = "AssignBunchTimingMC: bunchNumber = " + std::to_string(bunchNumber) + " | t0 = " + std::to_string(new_nu_time);
-        Log(logmessage, v_debug, verbosity);
+        std::ostringstream logmessage;
+        logmessage << "AssignBunchTimingMC: bunchNumber = " << bunchNumber
+                << " | t0 = " << new_nu_time
+                << " | sampled intrinsic bunch jitter = " << jitter << " ns"
+                << " | sampled BRF jitter = " << BRF_jitter << " ns";
+        Log(logmessage.str(), v_debug, verbosity);
     }
 
 }
@@ -292,8 +314,8 @@ void AssignBunchTimingMC::CalculateClusterAndBunchTimesPMTWaveformSim(std::vecto
         Log(logmessage, v_debug, verbosity);
     }
 
-    // calculate BunchTime
-    bunchTime = fbunchinterval * bunchNumber + clusterTime + jitter + new_nu_time ;
+    // calculate BunchTime (add the two gaussian contributions independently)
+    bunchTime = fbunchinterval * bunchNumber + clusterTime + jitter + BRF_jitter + new_nu_time ;
     if (verbosity >= v_debug) {
         std::string logmessage = "AssignBunchTimingMC: bunchTime = " + std::to_string(bunchTime);
         Log(logmessage, v_debug, verbosity);

UserTools/AssignBunchTimingMC/AssignBunchTimingMC.h

@@ -46,13 +46,16 @@ class AssignBunchTimingMC: public Tool {
         double fbunchwidth;       ///< BNB intrinsic bunch width in ns
         double fbunchinterval;    ///< BNB bunch spacing in ns
         int fbunchcount;          ///< number of BNB bunches per spill
+        double fBRF;              ///< BRF fit uncertainty extracted from the data (due to any additional electronic jitter unaccounted for)
         int fsample;              ///< GENIE Tank or WORLD samples
         int ftriggertime;         ///< whether the samples used the default WCSim prompt trigger = 0 (when particles enter the volume), or the adjusted prompt trigger based on the start of the beam dump
         bool fPMTWaveformSim;     ///< whether to use the PMTWaveform data-like hits or the defaul MCHits
 
+
         double new_nu_time;       ///< offset needed to make the cluster times beam realistic
         int bunchNumber;          ///< randomly assigned bunch number
         double jitter;            ///< random jitter based on the intrinsic bunch width
+        double BRF_jitter;        ///< random jitter based on the beam timing + fit uncertainties
         double bunchTime;         ///< individual bunch time assigned for a specific cluster
 
         /// \brief verbosity levels: if 'verbosity' < this level, the message type will be logged.

UserTools/AssignBunchTimingMC/README.md

@@ -15,16 +15,17 @@
 
 verbosity 0
 
-PMTWaveformSim 1       # Whether we're using the data-like hits output from PMTWaveformSim
-
 # BNB properties taken from: MicroBooNE https://doi.org/10.1103/PhysRevD.108.052010
-bunchwidth 1.308       # BNB instrinic bunch spread [ns]
-bunchinterval 18.936   # BNB bunch spacings [ns]
-bunchcount 81          # number of BNB bunches per spill
+bunchwidth 1.308          # BNB instrinic bunch spread [ns]
+bunchinterval 18.936      # BNB bunch spacings [ns]
+bunchcount 81             # number of BNB bunches per spill
+
+# Uncertainty extracted from Data / MC comparisons, see here: https://annie-docdb.fnal.gov/cgi-bin/sso/ShowDocument?docid=6489 
+BRFfituncertainty 1.809   # jitter in our beam signals / BRF fitting uncertainty [ns]
 
-sampletype 1           # Tank (0) or World (1) genie samples you are running over
-prompttriggertime 1    # WCSim prompt trigger settings: (0 = default, t0 = 0 when a particle enters the volume)
-                       #                                (1 = modified, t0 = 0 when the neutrino beam dump begins)
+sampletype 0              # Tank (0) or World (1) genie samples you are running over
+prompttriggertime 1       # WCSim prompt trigger settings: (0 = default, t0 = 0 when a particle enters the volume)
+                          #                                (1 = modified, t0 = 0 when the neutrino beam dump begins)
 ```
 
 

configfiles/BeamClusterAnalysisMC/AssignBunchTimingMCConfig

@@ -7,6 +7,8 @@ bunchwidth 1.308       # BNB instrinic bunch spread [ns]
 bunchinterval 18.936   # BNB bunch spacings [ns]
 bunchcount 81          # number of BNB bunches per spill
 
+BRFfituncertainty 1.809 # jitter in our beam signals / BRF fitting uncertainty [ns]
+
 sampletype 0           # Tank (0) or World (1) genie samples you are running over
 prompttriggertime 1    # WCSim prompt trigger settings: (0 = default, t0 = 0 when a particle enters the volume)
                        #                                (1 = modified, t0 = 0 when the neutrino beam dump begins)

configfiles/CC_MC_RECO_ntuple/AssignBunchTimingMCConfig

@@ -7,6 +7,8 @@ bunchwidth 1.308       # BNB instrinic bunch spread [ns]
 bunchinterval 18.936   # BNB bunch spacings [ns]
 bunchcount 81          # number of BNB bunches per spill
 
+BRFfituncertainty 1.809   # jitter in our beam signals / BRF fitting uncertainty [ns]
+
 sampletype 0           # Tank (0) or World (1) genie samples you are running over
 prompttriggertime 1    # WCSim prompt trigger settings: (0 = default, t0 = 0 when a particle enters the volume)
                        #                                (1 = modified, t0 = 0 when the neutrino beam dump begins)