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Title: Search for r-parity violating supersymmetry in multilepton final states with the D0 detector

Abstract

Results obtained from a search for the trilepton signature μμℓ (with ℓ = e, or μ) are combined with two complementary searches for the trilepton signatures eeℓ and eer and interpreted in the framework of R-parity violating Supersymmetry. Pairwise, R-parity conserving production of the supersymmetric particles is assumed, followed by R-parity violating decays via an LL$$\bar{E}$$-operator with one dominant coupling λ 122. An LL$$\bar{E}$$-operator couples two weak isospin doublet and one singlet (s)lepton fields and thus violates lepton number conservation. The data, collected with the D0 detector at the Fermilab proton-antiproton collider Tevatron, corresponds to an integrated luminosity of ∫ L dt = 360 ± 23 pb -1. No evident is observed, while 0.41 ± 0.11(stat) ± 0.07(sys) events are expected from Standard Model processes. The resulting 95% confidence level cross section limits on new physics producing a μμℓ signature in the detector are of the order of 0.020 to 0.136 pb. They are interpreted in two different supersymmetry scenarios: the mSUGRA and the MSSM model. The corresponding lower limits on the masses of the lightest neutralino ($$\tilde{X}$$$$0\atop{1}$$) and the lightest chargino ($$\tilde{X}$$$$±\atop{1}$$ in case of the mSUGRA model are found to be in the range of: mSUGRA, μ >more » 0: M($$\tilde{X}$$$$0\atop{1}$$) ~> 115-128 GeV and M($$\tilde{X}$$$$±\atop{1}$$) ~> 215-241 GeV; mSUGRA, μ < 0: ($$\tilde{X}$$$$0\atop{1}$$) ~> 101-114 GeV and M($$\tilde{X}$$$$±\atop{1}$$) ~> 194-230 GeV, depending on the actual values of the model parameters: m 0, m 1/2, A 0, tanβ, and μ. The first and second parameters provide the boundary conditions for the masses of the supersymmetric spin-0 and spin-1/2 particles, respectively, while A 0 gives the universal value for the trilinear couplings at the GUT scale. The parameter tan β denotes the ratio of the vacuum expectation values of the two Higgs fields and μ, finally, represents the Higgs mixing parameter. In the MSSM scenario the lower bound on the mass of the lightest chargino (for fixed neutralino mass) is found to be in the range of: M($$\tilde{X}$$$$±\atop{1}$$) ~> 205 GeV, for M($$\tilde{X}$$$$0\atop{1}$$) = 30 GeV; M($$\tilde{X}$$$$±\atop{1}$$) ~> 232 GeV, for M($$\tilde{X}$$$$0\atop{1}$$) = 200 GeV. The parameters of the considered MSSM model are: M 1, M 2, M 3, A 0, tan β, μ, and m A. The first three parameters define the common masses of the superpartners of the U(1) Y, SU(2) L, and SU(3) C bosons at the electroweak scale, respectively. The following three parameters are identical to those defined in the mSUGRA model above, while m A denotes the mass of the pseudoscalar Higgs boson, present in the supersymmetric extension of the Standard Model. In addition all sfermion masses are set to 1000 GeV.« less

Authors:
 [1]
  1. RWTH Aachen Univ. (Germany)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
907810
Report Number(s):
FERMILAB-THESIS-2006-22
TRN: US0703324
DOE Contract Number:  
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BOSONS; BOUNDARY CONDITIONS; CROSS SECTIONS; EXPECTATION VALUE; FERMILAB; FERMILAB TEVATRON; HIGGS BOSONS; ISOSPIN; LEPTON NUMBER; LUMINOSITY; PHYSICS; PSEUDOSCALARS; SPARTICLES; STANDARD MODEL; SUPERSYMMETRY; Experiment-HEP

Citation Formats

Kaefer, Daniela. Search for r-parity violating supersymmetry in multilepton final states with the D0 detector. United States: N. p., 2006. Web. doi:10.2172/907810.
Kaefer, Daniela. Search for r-parity violating supersymmetry in multilepton final states with the D0 detector. United States. https://doi.org/10.2172/907810
Kaefer, Daniela. Fri . "Search for r-parity violating supersymmetry in multilepton final states with the D0 detector". United States. https://doi.org/10.2172/907810. https://www.osti.gov/servlets/purl/907810.
@article{osti_907810,
title = {Search for r-parity violating supersymmetry in multilepton final states with the D0 detector},
author = {Kaefer, Daniela},
abstractNote = {Results obtained from a search for the trilepton signature μμℓ (with ℓ = e, or μ) are combined with two complementary searches for the trilepton signatures eeℓ and eer and interpreted in the framework of R-parity violating Supersymmetry. Pairwise, R-parity conserving production of the supersymmetric particles is assumed, followed by R-parity violating decays via an LL$\bar{E}$-operator with one dominant coupling λ122. An LL$\bar{E}$-operator couples two weak isospin doublet and one singlet (s)lepton fields and thus violates lepton number conservation. The data, collected with the D0 detector at the Fermilab proton-antiproton collider Tevatron, corresponds to an integrated luminosity of ∫ L dt = 360 ± 23 pb-1. No evident is observed, while 0.41 ± 0.11(stat) ± 0.07(sys) events are expected from Standard Model processes. The resulting 95% confidence level cross section limits on new physics producing a μμℓ signature in the detector are of the order of 0.020 to 0.136 pb. They are interpreted in two different supersymmetry scenarios: the mSUGRA and the MSSM model. The corresponding lower limits on the masses of the lightest neutralino ($\tilde{X}$$0\atop{1}$) and the lightest chargino ($\tilde{X}$$±\atop{1}$ in case of the mSUGRA model are found to be in the range of: mSUGRA, μ > 0: M($\tilde{X}$$0\atop{1}$) ~> 115-128 GeV and M($\tilde{X}$$±\atop{1}$) ~> 215-241 GeV; mSUGRA, μ < 0: ($\tilde{X}$$0\atop{1}$) ~> 101-114 GeV and M($\tilde{X}$$±\atop{1}$) ~> 194-230 GeV, depending on the actual values of the model parameters: m0, m1/2, A0, tanβ, and μ. The first and second parameters provide the boundary conditions for the masses of the supersymmetric spin-0 and spin-1/2 particles, respectively, while A0 gives the universal value for the trilinear couplings at the GUT scale. The parameter tan β denotes the ratio of the vacuum expectation values of the two Higgs fields and μ, finally, represents the Higgs mixing parameter. In the MSSM scenario the lower bound on the mass of the lightest chargino (for fixed neutralino mass) is found to be in the range of: M($\tilde{X}$$±\atop{1}$) ~> 205 GeV, for M($\tilde{X}$$0\atop{1}$) = 30 GeV; M($\tilde{X}$$±\atop{1}$) ~> 232 GeV, for M($\tilde{X}$$0\atop{1}$) = 200 GeV. The parameters of the considered MSSM model are: M1, M2, M3, A0, tan β, μ, and mA. The first three parameters define the common masses of the superpartners of the U(1)Y, SU(2)L, and SU(3)C bosons at the electroweak scale, respectively. The following three parameters are identical to those defined in the mSUGRA model above, while mA denotes the mass of the pseudoscalar Higgs boson, present in the supersymmetric extension of the Standard Model. In addition all sfermion masses are set to 1000 GeV.},
doi = {10.2172/907810},
url = {https://www.osti.gov/biblio/907810}, journal = {},
number = ,
volume = ,
place = {United States},
year = {2006},
month = {10}
}

Thesis/Dissertation:
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