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SUSY searches using Vector Boson Fusion processes in the LHC. Andrés Leonardo Cabrera Mora Andrés Flórez , Bernardo Gómez. Departamento de Física Bogotá , Colombia. activities at CERN for RPC Group from CMS Experiment. Skew and Delay Test for the RPC Signal Cables.
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SUSY searchesusing Vector BosonFusionprocesses in the LHC Andrés Leonardo Cabrera Mora Andrés Flórez , Bernardo Gómez Departamento de Física Bogotá, Colombia
Skew and Delay Test for the RPC Signal Cables Cables tested: 864 Example of the test
Test of HV Adaptorsfor RPC Jupiterconnector Tripolarconnector V0 = 15 KV I0 = 3μA Trip Time = 3 sec 0< I < 0.2 μA
Test of HV Cables HV Cable Adaptor Long Test (48 hours) Fast Test (30 min) V0 = 12 KV I0 = 3μA Trip Time = 3 sec 0< I < 0.3 μA V0 = 15 KV I0 = 3μA Trip Time = 3 sec 0< I < 0.2 μA
Reshuffling code for the RPC HV System Distributors (Back) • Task • Reshuffle endcap HV cables (RE1, RE2, RE3) to group chambers with close working points. • Goal • Bring actual working point for every chamber close to ideal WP to increase overall chamber efficiency. Distributors (Front)
Installation of RPC Signal Cable for RE+4. • Participation in theinstallation of thesignal cables forthe RE+4 • In the rack side • In thechamberside
Gasleaksearch for the RPC Gas Pipes • Search of gas leaks in the RPC gas pipes • LeakMeasurementusing: • Ar gas withPico data logger • LeakBox • N2H2gas • HydrogenLeak Detector (H2000+) Someresults: W-1 260 L/h -> 160 L/h
Search of DarkMatter at the LHC in VBF processesusing SUSY models. Forward tagging jets m MET + jj + muons f m h
VFB Jets VBF related distributions for V + jets and VBF production of a charginopair. As expected, the jets in V + jets events are mostly central and have small dijet invariant masses.
VFB Jets VBF related distributions for V + jets and VBF production of a charginopair. The outgoing partons in VBF processes must carry relatively large pT
Strategy • Presence of two energetic jets in the forward direction in opposite hemispheres, and with large dijetinvariant mass. • RelativelyhighMissing ET requirement is imposed due to the presence of the LSP • Twomuons in the final state are expectedforthischannel • VBF SUSY productioncross-sections are relatively small
Workalready done • Gitaccount • AndresFlorez tutorial of thecode • sourcesetupCode_5_3_11_patch6.sh • Gridcertificate • Come back to CERN bytheend of January
Conclusions • Ready to work¡¡¡
Figure 1: Diagrams of chargino-neutralino and chargino-chargino pair production through vector boson fusion followed by their decays to leptons and a LSP.
Lo que conocemos • Toda la materia que conocemos compone el 4% de la materia total del universo (protones, neutrones, electrones, etc) • ¿Dónde esta el resto? • 74 % DarkEnergy • 22 % Materia Oscura
WHAT’S OUT THERE? • Astronomy tells us: • The matter we know (i.e. protons, neutrons and electrons) accounts for just 5% of the universe • The rest is dark matter • And dark energy SLAC/Nicole Rager
Supersimetría? Composición de la materia Modelo Estándar Bosones Fermiones Fermion Quarks Leptones Supercompañero Boson Supercompañero Masas Grandes
Supersimetría? Composición de la materia Modelo Estándar Bosones Fermiones Fermion Quarks Leptones Supercompañero Boson Supercompañero Masas Grandes
Paridad R • La partícula supersimétrica mas liviana (LSP) es estable • El decaimiento de productos de spartículas debe contener un número impar de LSPs. • Las supercompañeras de las partículas del SM deben ser producidas en pares.
Objetivo • Buscar Materia Oscura en el LHC asociada a procesos VFB utilizando modelos Supersimétricos.
Results 2012 Di-photon (γγ ) invariant mass distribution for the CMS data of 2011 and 2012 (black points with error bars). The data are weighted by the signal to background ratio for each sub-category of events. The solid red line shows the fit result for signal plus background; the dashed red line shows only the background.
supersymmetry? Mattercomposition Standard Model Bosons Fermions Quarks Lepton
supersymmetry? Mattercomposition Standard Model Bosons Fermions S-Fermion Quarks Lepton S-Boson
WHAT’S OUT THERE? The matter we know (i.e. protons, neutrons and electrons) accounts for just 4% of the universe The rest is: 74 % DarkEnergy 22 % Materia Oscura
supersymmetry? Supersimetría • Theoreticalproblems of theSM • CandidatetoDarkMatter (LSP)
supersymmetry? Mattercomposition Standard Model Bosons Fermions S-Fermion Quarks Lepton S-Boson Big Mass
R - Parity • Thelightestsusyparticle (LSP) isstablebyconservation of R parity. • Decays productsof s-particles should contain an odd number of LSPs. • The superpartners of the SM are produced in pairs.
ClassicSetting (ModelDependent) ExclusionLimitsforsquarks and gluinos. 1.5 TeV 95%
Workalready done • Gitaccount • AndresFlorez tutorial of thecode • sourcesetupCode_5_3_11_patch6.sh • Gridcertificate • Crab?? • Run thecode??
PhysicsObjectReconstruction: Electrons
Software Requirements MC Generator: POWHEG, MADGRAPH, TAUOLA, Pythia,etc. Analysis software: CMSSW, Root, etc. ObjectReconstruction: Criteria selection defined by CMS
PhysicsObjectReconstruction: Jets anti-kT clustering algorithm with a reconstruction cone of R = 0.5 is used
PreviousResults • Number of observed events in data and estimated background rates in the search region. The numbers are for L = 10.9 fb-1
Conclusions • The observed number of events in the signal regions shown do not reveal any evidence for VBF SUSY production. • Theresultsarepresented in the context of the R-parity conserving Minimal Supersymmetric Standard Model and considering cases such as VBF electroweak production of charginos and neutralinos. • VBF offers a powerful way to “directly” probe EWK SUSY at the LHC. • Direct window to determination the composition of the LSP.
MainPurpose • Search of DarkMatter at the LHC in VBF processesusing SUSY models.