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+# SMS Long-lived particle MC production
+This repository contains the CMSSW and CRAB config files used to generate SMS
+LLP (long-lived particle) MC.
+
+## Setup the environment
+
+### Everytime you login
+Source the relevant CMS environment, crab environment and setup your grid proxy:
+```bash
+source /cvmfs/cms.cern.ch/cmsset_default.sh
+source /cvmfs/cms.cern.ch/crab3/crab.sh
+voms-proxy-init --voms cms --valid 168:00
+```
+
+### Only once
+Create a directory to keep all your LLP files and directories and move into it.
+Checkout the master branch of this repository:
+```bash
+git clone git@github.com:benkrikler/LLP_generation.git
+cd LLP_generation
+```
+
+Checkout CMSSW version `8_0_21`:
+```bash
+export SCRAM_ARCH=slc6_amd64_gcc530
+cmsrel CMSSW_8_0_21
+cd CMSSW_8_0_21/src
+cmsenv
+mkdir -p Configuration/GenProduction/python/
+cp ../../T1qqqqLL_cfg.py Configuration/GenProduction/python/
+scram b -j 9
+cd -
+```
+
+## Commands to produce the CMSSW config files
+This repository already contains the files produced by the following commands.
+But for reference, here are the commands for each step.
+
+### GEN-SIM
+Runs Madgraph and Pythia
+```bash
+cmsDriver.py Configuration/GenProduction/python/T1qqqqLL_fragment.py \
+    --mc \
+    --eventcontent RAWSIM \
+    --customise_commands "process.source.numberEventsInLuminosityBlock = cms.untracked.uint32(50) \n process.source.firstRun = cms.untracked.uint32(3) \n process.generator.initialSeed = cms.untracked.uint32(3)" \
+    --datatier GEN-SIM \
+    --conditions 80X_mcRun2_asymptotic_2016_TrancheIV_v6 \
+    --beamspot Realistic50ns13TeVCollision \
+    --step GEN,SIM \
+    --magField 38T_PostLS1  \
+    --fileout file:T1qqqqLL_GEN-SIM.root \
+    --python_filename T1qqqqLL_GEN-SIM_cfg.py \
+    --no_exec \
+    -n 50
+```
+
+### PU Mixing
+Run the PU mixing step over all events produced by the GEN-SIM step
+```bash
+cmsDriver.py step1 \
+    --mc \
+    --eventcontent PREMIXRAW \
+    --datatier GEN-SIM-RAW \
+    --conditions 80X_mcRun2_asymptotic_2016_TrancheIV_v6 \
+    --step DIGIPREMIX_S2,DATAMIX,L1,DIGI2RAW,HLT:@frozen2016 \
+    --nThreads 4 \
+    --datamix PreMix \
+    --era Run2_2016 \
+    --filein file:T1qqqqLL_GEN-SIM.root \
+    --fileout file:T1qqqqLL_PUMix.root \
+    --pileup_input "/store/mc/RunIISpring15PrePremix/Neutrino_E-10_gun/GEN-SIM-DIGI-RAW/PUMoriond17_80X_mcRun2_asymptotic_2016_TrancheIV_v2-v2/90023/FED016AB-6A85-E611-96E7-002590A80DF0.root" \
+    --no_exec \
+    -n -1
+```
+
+### AODSIM
+```bash
+cmsDriver.py step2 \
+    --mc \
+    --eventcontent AODSIM,DQM \
+    --runUnscheduled \
+    --datatier AODSIM,DQMIO \
+    --conditions 80X_mcRun2_asymptotic_2016_TrancheIV_v6 \
+    --step RAW2DIGI,RECO,EI,DQM:DQMOfflinePOGMC \
+    --nThreads 4 \
+    --era Run2_2016 \
+    --filein file:T1qqqqLL_PUMix.root \
+    --fileout file:T1qqqqLL_AODSIM.root \
+    --no_exec \
+    -n -1
+```
+
+### MINIAODSIM
+```bash
+cmsDriver.py step1 \
+    --mc \
+    --eventcontent MINIAODSIM \
+    --runUnscheduled \
+    --datatier MINIAODSIM \
+    --conditions 80X_mcRun2_asymptotic_2016_TrancheIV_v6 \
+    --step PAT \
+    --era Run2_2016 \
+    --filein file:T1qqqqLL_AODSIM.root \
+    --fileout file:T1qqqqLL_MINIAODSIM.root \
+    --no_exec \
+    -n -1
+```
+
+## How to submit
+To submit locally, just run pass the CMSSW config file to cmsRun:
+```bash
+cmsRun ${CMSSW_CFG}
+```
+
+To submit to the grid using CRAB, pass the CRAB config file to the relevant crab
+commands:
+```bash
+crab submit -c ${CRAB_CFG}
+```
+
+To monitor your grid job:
+```bash
+crab status -d ${CRAB_DIR}
+```
+
+There are many other fun CRAB commands that I will let you discover yourself.