susy searches using vector boson fusion processes in the lhc departamento de física bogotá,...

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?

30

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?

33

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

40

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.