MC/PWGEM: add cfg and ini for VM2ll

Author: dsekihat

MC/config/PWGEM/ini/pythia8_OO_VM2ll.ini

@@ -0,0 +1,9 @@
+[Diamond]
+width[2]=6.0
+
+[GeneratorExternal]
+fileName=${O2DPG_MC_CONFIG_ROOT}/MC/config/ALICE3/pythia8/generator_pythia8_ALICE3.C
+funcName=generator_pythia8_ALICE3()
+
+[GeneratorPythia8]
+config=${O2DPG_MC_CONFIG_ROOT}/MC/config/PWGEM/pythia8/generator/pythia8_OO_536_VM2ll.cfg

MC/config/PWGEM/pythia8/generator/pythia8_OO_536_VM2ll.cfg

@@ -0,0 +1,21 @@
+### OO beams
+Beams:idA = 1000080160
+Beams:idB = 1000080160           
+Beams:eCM = 5360.0                ### energy
+    
+Beams:frameType = 1
+ParticleDecays:limitTau0 = on
+ParticleDecays:tau0Max = 10.      ### match alice: 1cm/c = 10.0mm/c
+
+### Save some CPU at init of jobs
+### To avoid refitting, add the following lines to your configuration file:
+HeavyIon:SigFitNGen = 0
+HeavyIon:SigFitDefPar = 2.15,18.42,0.33
+    
+Random:setSeed = on
+
+# change omega, phi meson's BR below
+223:oneChannel = 1 0.5 0 -11 11
+223:addChannel = 1 0.5 0 -13 13
+333:oneChannel = 1 0.5 0 -11 11
+333:addChannel = 1 0.5 0 -13 13