SUSY searches using Vector Boson Fusion processes in the LHC

Departamento de FísicaBogotá, Colombia

Andrés Leonardo Cabrera MoraAndrés Flórez , Bernardo Gómez

ACTIVITIES AT CERN FOR RPC GROUP FROM CMS EXPERIMENT

Skew and Delay Test for the RPC Signal Cables

CABLE NAME DELAY MAX SKEW RESULTRE+4/3/11/A1/CA1/X4A51_i/L9/J1 68,78 0,85 OKRE+4/3/11/A2/CA1/X4A51_i/L9/J2 68,75 0,78 OKRE+4/3/11/B1/CA1/X4A51_i/L9/J3 63,51 0,73 OKRE+4/3/11/B2/CA1/X4A51_i/L9/J4 63,63 0,76 OKRE+4/3/11/C1/CA1/X4A51_i/L9/J5 63,43 0,79 OKRE+4/3/11/C2/CA1/X4A51_i/L9/J6 63,51 0,69 OK

RE+4/3/12/C2/CA1/X4A51_i/L17/J6 56,79 0,72 OK

RE+4/3/12/C1/CA1/X4A51_i/L17/J5 56,9 0,73 OKRE+4/3/12/B2/CA1/X4A51_i/L17/J4 56,88 0,68 OKRE+4/3/12/B1/CA1/X4A51_i/L17/J3 56,83 0,68 OKRE+4/3/12/A2/CA1/X4A51_i/L17/J2 61,98 0,81 OKRE+4/3/12/A1/CA1/X4A51_i/L17/J1 62,06 0,73 OK

RE+4/3/24/C2/CA1/X2A52_d/L17/J6 43,49 0,62 OKRE+4/3/24/C1/CA1/X2A52_d/L17/J5 43,54 0,48 OKRE+4/3/24/B2/CA1/X2A52_d/L17/J4 43,48 0,56 OKRE+4/3/24/B1/CA1/X2A52_d/L17/J3 43,63 0,55 OKRE+4/3/24/A2/CA1/X2A52_d/L17/J2 48,68 0,57 OKRE+4/3/24/A1/CA1/X2A52_d/L17/J1 48,75 0,62 OK

RE+4/3/22/A1/CA1/X2A52_d/L8/J1 33,24 0,32 OKRE+4/3/22/A2/CA1/X2A52_d/L8/J2 33,26 0,36 OKRE+4/3/22/B1/CA1/X2A52_d/L8/J3 28,26 0,47 OKRE+4/3/22/B2/CA1/X2A52_d/L8/J4 28,18 0,32 OKRE+4/3/22/C1/CA1/X2A52_d/L8/J5 28,24 0,42 OKRE+4/3/22/C2/CA1/X2A52_d/L8/J6 28,21 0,28 OK

Cables tested: 864Example of the test

Test of HV Adaptors for RPC

V0 = 15 KVI0 = 3μATrip Time = 3 sec0< I < 0.2 μA

Tripolar connector

Jupiter connector

Fast Test (30 min) Long Test (48 hours)

I0Set (uA)

Vmon (V)

Imon (uA)

Trip Time (sec) Trip ? Test I0Set

(uA)Vmon (V)

Imon (uA)

Trip Time (sec) Trip ? Test Reason

Adaptor 1 3 14998 0,1 3 No Ok 3 12003 0,89 3 No Fail I >0,3Adaptor 1 3 14997 0,1 3 No Ok 3 12003 0 3 No Fail I >0,3Adaptor 2 3 14998 0,1 3 No Ok 3 12004 0 3 No Ok Adaptor 2 3 14998 0 3 No Ok 3 12000 0 3 No Ok Adaptor 3 3 15000 0,2 3 No Ok 3 11998 0 3 No Ok Adaptor 3 3 14998 0,1 3 No Ok 3 11998 0,1 3 No Ok Adaptor 4 3 14998 0,1 3 No Ok 3 12013 0 3 No Ok Adaptor 4 3 14997 0,1 3 No Ok 3 12008 0 3 No Ok Adaptor 5 3 14999 0,1 3 No Ok 3 12014 0 3 No Ok Adaptor 5 3 14998 0 3 No Ok 3 12007 0 3 No Ok Adaptor 6 3 15001 0,2 3 No Ok 3 11998 0,2 3 No Ok Adaptor 6 3 14998 0 3 No Ok 3 11998 0 3 No Ok Adaptor 7 3 14998 0,1 3 No Ok 3 11999 0 3 No Ok Adaptor 7 3 14997 0,1 3 No Ok 3 12001 0 3 No Ok Adaptor 8 3 15000 0 3 No Ok 3 5 0 3 Yes Fail TrippedAdaptor 8 3 14998 0 3 No Ok 3 11997 0,2 3 No Fail TrippedAdaptor 9 3 15001 0,1 3 No Ok 3 11998 0 3 No Ok Adaptor 9 3 14998 0 3 No Ok 3 11999 0,3 3 No Ok

Adaptor

HV

Cabl

eTest of HV Cables

Fast Test (30 min)V0 = 15 KVI0 = 3μATrip Time = 3 sec0< I < 0.2 μA

Long Test (48 hours)V0 = 12 KVI0 = 3μATrip Time = 3 sec0< I < 0.3 μA

Reshuffling code for the RPC HV System

• 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 (Back)

Distributors (Front)

Installation of RPC Signal Cable for RE+4.

• Participation in the installation of the signal cables for the RE+4– In the rack side– In the chamber side

Gas leak search for the RPC Gas Pipes

• Search of gas leaks in the RPC gas pipes• Leak Measurement using:

– Ar gas with Pico data logger – Leak Box – N2H2 gas – Hydrogen Leak Detector

(H2000+)

Some results:W-1 260 L/h -> 160 L/h

ANALYSIS WORK

h

f

Forward tagging jets

MET + jj + muonsm

m

Search of Dark Matter at the LHC in VBF processes using SUSY models.

VFB Jets

VBF related distributions for V + jets and VBF production of a chargino pair.

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 chargino pair.

The outgoing partons in VBFprocesses must carry relatively large pT

Missing Transverse Energy

Strategy

• Presence of two energetic jets in the forward direction in opposite hemispheres, and with large dijet invariant mass.

• Relatively high Missing ET requirement is imposed due to the presence of the LSP

• Two muons in the final state are expected for this channel

• VBF SUSY production cross-sections are relatively small

Work already done

• Git account• Andres Florez tutorial of the code

– source setupCode_5_3_11_patch6.sh• Grid certificate• Come back to CERN by the end of January

Conclusions

• Ready to work¡¡¡

BACKUP SLIDES

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Figure 1: Diagrams of chargino-neutralino and chargino-chargino pair production through vectorboson fusion followed by their decays to leptons and a LSP.

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.

Distribution of the four-lepton reconstructed mass for the sum of the 4e, 4μ, and 2e2μ

channels. Points represent the data, shaded histograms represent the background and un-shaded histogram the signal expectations. The

distributions are presented as stacked histograms. The measurements are presented for the sum of the data collected at centre of mass energies of

7 TeV and 8 TeV.

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Lo que conocemosToda la materia que conocemos compone el 4% de la materia total del universo (protones, neutrones, electrones, etc)

¿Dónde esta el resto?

74 % Dark Energy22 % 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 SL

AC/N

icol

e Ra

ger

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Composición de la materia

Bosones Fermiones

Quarks Leptones

Modelo Estándar

SUPERSIMETRÍA?

Supercompañero

Supercompañero

Boson

Fermion

Masas Grandes

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Composición de la materia

Bosones Fermiones

Quarks Leptones

Modelo Estándar

SUPERSIMETRÍA?

Supercompañero

Supercompañero

Boson

Fermion

Masas Grandes

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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.

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Parámetro η : La seudorapidez

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.

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Matter composition

Bosons Fermions

Quarks Lepton

Standard Model

SUPERSYMMETRY?

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Matter composition

Bosons Fermions

Quarks Lepton

Standard Model

SUPERSYMMETRY?

S-Boson

S-Fermion

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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 % Dark Energy22 % Materia Oscura

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Supersimetría

• Theoretical problems of the SM• Candidate to Dark Matter (LSP)

SUPERSYMMETRY?

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Matter composition

Bosons Fermions

Quarks Lepton

Standard Model

SUPERSYMMETRY?

S-Boson

S-Fermion

Big Mass

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R - Parity

• The lightest susy particle (LSP) is stable by conservation of R parity.

• Decays products of s-particles should contain an odd number of LSPs.

• The superpartners of the SM are produced in pairs.

Classic Setting (Model Dependent)

Exclusion Limits for squarks and gluinos.1.5 TeV 95%

Work already done

• Git account• Andres Florez tutorial of the code

– source setupCode_5_3_11_patch6.sh• Grid certificate• Crab??• Run the code??

Physics Object Reconstruction: Electrons

Muon Reconstruction and Identification

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Missing Transverse Energy

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η: Pseudorapidity

Software Requirements

MC Generator:POWHEG, MADGRAPH, TAUOLA, Pythia,etc.Analysis software:CMSSW, Root, etc.Object Reconstruction:Criteria selection defined by CMS

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Physics Object Reconstruction: Jets

anti-kT clustering algorithm with a reconstruction cone of

R = 0.5 is used

Previous Results• 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.

• The results are presented 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.

Main Purpose

• Search of Dark Matter at the LHC in VBF processes using SUSY models.