== Jet Radiation in SUSY events == === People === 1. Johan Alwall 1. Simon de Visscher 1. Fabio Maltoni === Aim of the project === We study QCD radiation in SUSY events, such as gluino-gluino, stop-stop, stop-gluino processes. We use the MLM matching and verify/improve the results of [http://arxiv.org/abs/hep-ph/0510144 Tilman, David and Peter], and in particular we investigate whether the extra hard jets in SUSY events are well described by the parton-shower, as it is usually claimed, or if matching gives a better description. We also study the matching in heavy tops events as a reference and the SM background needed in these kind of analysis. The SM samples will be used also for other applications. === Tools === * Madgraph/MadEvent v4 : SUSY and matching * [https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/MadMatchChecker MadMatchChecker] === Work === We have identified two phases: 1. MC samples generation and validation 2. Physics results and paper writeup ==== MC samples generation and validation ==== The strategy here is to first generate samples at the after-showering level to perform the validation. Once all samples are validated, we'll do the full Pythia-PGS simulation. ===== Generation ===== ====== Standard Model Samples (Simon) ====== To get a faster generation we: * define a new model (smzerobmass), where the bmass is set to "Zero" in the particles.dat. This optimizes the flavor sum * We don't decay the Z, W+,W-, and tops. We'll let these particles be decayed by Pythia. In doing this we loose spin correlations, which, however are irrelevant for the multi-jet samples for this type of studies. * Not to generate the single particle samples for Z and W. These have a negligible impact on the multi-jet configurations we are interested in. * In Pythia, we consider only decays of W into leptons (e, mu and tau) and also into neutrinos for Z. ====== SUSY and SM Samples ====== ||'''Process'''||'''Webpage'''||'''section(s)'''||'''LHE (on disks)'''||'''Pythia'''||'''MC'''||'''PGS'''|| ||1. '''gogo at 607 GeV (sps1a)'''||n/a|| all ||ok||ok||ok || || ||1a. '''SC 1'''||n/a||4||ok||ok||||n/a || ||1b. '''SC 2'''||n/a||4||ok||||||n/a || ||1c. '''SC 3'''||n/a||4||ok||||||n/a || ||1d. '''SC 4'''||n/a||4||ok||||||n/a || ||1e. '''QCUT x 2'''||n/a||3.1||ok||||||n/a || ||2. '''gogo at 607 GeV with xqcut and QCUT / 2'''||[http://madgraph.phys.ucl.ac.be/MadGraphData/simon.devisscher@uclouvain.be/PROC40/HTML/crossx.html here] ||3.1 || || || ||n/a || ||3. '''gogo at 607 GeV with scales divided by 2'''||[http://madgraph.phys.ucl.ac.be/MadGraphData/simon.devisscher@uclouvain.be/PROC40/HTML/crossx.html here] ||3 ||ok || || ||n/a || ||4. '''gogo at 607 GeV with scales multiplied by 2'''||[http://madgraph.phys.ucl.ac.be/MadGraphData/simon.devisscher@uclouvain.be/PROC40/HTML/crossx.html here]||3 ||ok|| || ||n/a || ||5. '''gogo at 300 GeV'''|| ||4 ||ok ||ok||ok||n/a || ||6. '''gogo at 1200 GeV'''|| ||4 ||ok||ok ||ok||n/a || ||7. '''sqsq at sps1a'''||n/a ||4,5||ok|| || || || ||8. '''sqgo at sps1a'''||n/a||4,5||ok|| || || || ||9. '''ulul at 607 GeV'''||[http://madgraph.hep.uiuc.edu/MadGraphData/devisscher@fynu.ucl.ac.be/PROC30/HTML/crossx.html here] ||3,4 ||ok ||ok || ||n/a || ||10. '''ulul at 607 GeV with scales divided by 2'''||[http://madgraph.hep.uiuc.edu/MadGraphData/johan@alwall.net/PROC60/HTML/crossx.html here]||3 ||ok ||ok ||ok ||n/a || ||11. '''ulul at 607 GeV with scales multiplied by 2'''||[http://madgraph.hep.uiuc.edu/MadGraphData/johan@alwall.net/PROC60/HTML/crossx.html here] ||3 ||ok ||ok ||ok||n/a || ||12. '''ululbar at 607 GeV'''||[http://madgraph.hep.uiuc.edu/MadGraphData/devisscher@fynu.ucl.ac.be/PROC31/HTML/crossx.html here] ||3,4 ||ok ||ok ||ok ||n/a || ||13. '''ululbar at 607 GeV with scales divided by 2'''||[http://madgraph.hep.uiuc.edu/MadGraphData/devisscher@fynu.ucl.ac.be/PROC37/HTML/crossx.html here] ||3 ||ok ||ok ||ok ||n/a || ||14. '''ululbar at 607 GeV with scales multiplied by 2'''||[http://madgraph.hep.uiuc.edu/MadGraphData/devisscher@fynu.ucl.ac.be/PROC37/HTML/crossx.html here] ||3 ||ok||ok||ok||n/a || ||15. '''ttbar'''||n/a||3,5||ok||ok ||ok|| || ||15a. '''QCUT x 2'''||n/a||3,5||ok|| || ||n/a || ||16. '''ttbar with xqcut and QCUT / 2'''||n/a||3.1 || || || ||n/a || ||17. '''ttbar with scales divided by 2'''||[http://madgraph.phys.ucl.ac.be/MadGraphData/johan@alwall.net/PROC169/HTML/crossx.html here]||3 ||ok||ok ||ok||n/a || ||18. '''ttbar with scales multiplied by 2'''||[http://madgraph.phys.ucl.ac.be/MadGraphData/johan@alwall.net/PROC169/HTML/crossx.html here] ||3 ||ok ||ok ||ok || n/a || ||19. '''W+4 jets biaised'''||n/a||5 ||ok || || || || ||20. '''W+3 jets biaised'''||[http://madgraph.phys.ucl.ac.be/MadGraphData/simon.devisscher@uclouvain.be/PROC37/HTML/crossx.html here]||5||ok|| || || || ||21. '''Z+4 jets biaised'''||n/a||5 ||ok|| || || || ==== Physics results and paper writeup ==== ===== Plots for the paper ===== Explanation of notation: * 4x2 runs means 4 unmatched, 4 matched runs with the different shower params * 4 params means with the 4 different shower params * decay jet #s means number of jets from decays * jet numbers means plot of number of jets above (say) 50 GeV in the events ||'''Figure'''||'''section'''||'''Process(es)'''||'''Description'''||'''Done (plan)'''||'''plot'''|| || 1 || 2 || n/a ||Feynman diagrams illustrating resonance double counting (3 plots) ||done|||| || 2 || 3.1 || 1,1e,2,15,15a,16 ||Standard validation plots: diff. jet rates 0,1,2 with QCUT, x2, /2 for pT- and Q2-ordered showers, for gogo and ttbar (4x3x3 plots)|| ? |||| || 3a || 3.2 || 15 (4x2 runs),16,17 ||pT of 1st and 2nd extra jet in ttbar, unmatched and matched dep on shower params, scale dep. for matched (4 plots) || 6-7/08 ||[attachment:Pt_ttbar.eps Pt_ttbar.eps]|| || 3b || 3.2 || 1 (4x2 runs),3,4 ||pT of 1st and 2nd extra jet in gogo, unmatched and matched dep on shower params, scale dep. for matched (4 plots) || 8/08? ||[attachment:Pt_gogo.eps Pt_gogo.eps]|| || 4(7) || 3.3 || 1,9,12 ||HTred and pTs, matched for gogo, ulul and ulul* 600 GeV (3 plots) || 11/08 ||[attachment:Htred.eps Htred.eps]|| || 5(6) || 3.3 || 1,5,6 ||pT of 1st-2nd extra jet and HTred, matched for gogo at 300, 600, 1200 GeV (2x3 plots) || 11/08 ||[attachment:pt_300_600_1200.eps pt_300_600_1200.eps]|| || 6a(8) || 4 || 1a (4x2 runs) ||HT(n),n=3,4,5(?) matched for gogo with decay jet #s, ETmiss unmatched and matched for sc. 1 (4 plots) || 6-7/08 ||[attachment:htcontrib-mockup.eps htcontrib-mockup.eps]|| || 6b(9) || 4 || 1b (4x2 runs) ||HT(n),n=3,4,5(?) matched for gogo with decay jet #s, ETmiss unmatched and matched for sc. 2 (4 plots) || ||[attachment:htcontrib-sc2.eps htcontrib-sc2.eps]|| || 7(10) || 4.1 || 1a (4 unm runs),12 ||HT(n),n=2,3,4 and jet numbers for unmatched gogo sc. 1 (4 params) and matched ululbar sc. 3 (2x4 plots) || 12/08 |||| || 8(11) || 4.2 || 1d (4x2 runs) ||ETmiss unmatched and matched (1 plot) || 12/08 |||| For sec. 5 we should plot the most important quantities used in typical experimental analyses, such as ETmiss, HT(4), and what else? All after PGS. -- Main.JohanAlwall - 05 Aug 2008 * [attachment:Pt_ulul.eps Pt_ulul.eps]: Pt of 1rst and 2nd jet for ulul * [attachment:Pt_ululbar.eps Pt_ululbar.eps]: Pt of 1rst and 2nd jet for ululbar * [attachment:Htred.eps Htred.eps]: Ht red for gogo, ulul and ululbar, as well as Pt of 1rst and second, all with and without matching * [attachment:htcontrib-mockup.eps htcontrib-mockup.eps]: contrib of jets to Ht scenario 1 * [attachment:Pt_ttbar.eps Pt_ttbar.eps]: pt for ttbar * [attachment:pt_300_600_1200.eps pt_300_600_1200.eps]: characteristic of jets for in gogo for go mass=300, 600 and 1200 GeV * [attachment:Pt_gogo.eps Pt_gogo.eps]: pt of the 1rst and 2nd jet for gogo (with ME and PS) * [attachment:Pt_ulul.eps Pt_ulul.eps]: Pt of two leading jets for ulul * [attachment:Pt_ululbar.eps Pt_ululbar.eps]: pt of leading jets for ululbar * [attachment:Htred.eps Htred.eps]: Htred and Pt for gogo, ulul and ululbar, Pythia vs ME * [attachment:Pt_ttbar.eps Pt_ttbar.eps]: Pt_ttbar.eps * [attachment:Pt_ulul.eps Pt_ulul.eps]: Pt_ulul.eps * [attachment:Pt_ululbar.eps Pt_ululbar.eps]: Pt_ululbar.eps * [attachment:Pt_ulul.eps Pt_ulul.eps]: Pt_ulul.eps * [attachment:pt_300_600_1200.eps pt_300_600_1200.eps]: pt_300_600_1200.eps * [attachment:htcontrib-sc2.eps htcontrib-sc2.eps]: preliminary plot showing the contribution of decay jets to Ht and MET for scenario2 * [attachment:Htred.eps Htred.eps]: Htred.eps