# Charged sleptons

This section contains limits on charged scalar leptons (${{\widetilde{\mathit \ell}}}$, with ${{\mathit \ell}}={{\mathit e}},{{\mathit \mu}},{{\mathit \tau}}$). Studies of width and decays of the ${{\mathit Z}}$ boson (use is made here of $\Delta \Gamma _{{\mathrm {inv}}}<2.0~$MeV, LEP 2000 ) conclusively rule out ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{R}}}}<40~$GeV (41 GeV for ${{\widetilde{\mathit \ell}}_{{L}}}$) , independently of decay modes, for each individual slepton. The limits improve to 43$~$GeV ($43.5$ GeV for ${{\widetilde{\mathit \ell}}_{{L}}}$) assuming all 3 flavors to be degenerate. Limits on higher mass sleptons depend on model assumptions and on the mass splitting $\Delta \mathit m$= ${\mathit m}_{{{\widetilde{\mathit \ell}}}}–{\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$. The mass and composition of ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$ may affect the selectron production rate in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions through ${{\mathit t}}$-channel exchange diagrams. Production rates are also affected by the potentially large mixing angle of the lightest mass eigenstate ${{\widetilde{\mathit \ell}}_{{1}}}={{\widetilde{\mathit \ell}}_{{R}}}$ sin$\theta _{{{\mathit \ell}}}$ + ${{\widetilde{\mathit \ell}}_{{L}}}$ cos $\theta _{{{\mathit \ell}}}$. It is generally assumed that only ${{\widetilde{\mathit \tau}}}$ may have significant mixing. The coupling to the ${{\mathit Z}}$ vanishes for $\theta _{{{\mathit \ell}}}$=0.82. In the high-energy limit of ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions the interference between ${{\mathit \gamma}}$ and ${{\mathit Z}}$ exchange leads to a minimal cross section for $\theta _{{{\mathit \ell}}}$=0.91, a value which is sometimes used in the following entries relative to data taken at LEP2. When limits on ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{R}}}}$ are quoted, it is understood that limits on ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{L}}}}$ are usually at least as strong.
Possibly open decays involving gauginos other than ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$ will affect the detection efficiencies. Unless otherwise stated, the limits presented here result from the study of ${{\widetilde{\mathit \ell}}^{+}}{{\widetilde{\mathit \ell}}^{-}}$ production, with production rates and decay properties derived from the MSSM. Limits made obsolete by the recent analyses of ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions at high energies can be found in previous Editions of this Review.
For decays with final state gravitinos (${{\widetilde{\mathit G}}}$), ${\mathit m}_{{{\widetilde{\mathit G}}}}$ is assumed to be negligible relative to all other masses.

# R-parity conserving ${{\widetilde{\boldsymbol \mu}}}$ (Smuon) mass limit INSPIRE search

VALUE (GeV) CL% DOCUMENT ID TECN  COMMENT
$\bf{> 210}$ 95 1
 2019 AW
CMS ${{\mathit \ell}^{\pm}}{{\mathit \ell}^{\mp}}$ + $\not E_T$, ${{\widetilde{\mathit \mu}}_{{R}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$> 280$ 95 1
 2019 AW
CMS ${{\mathit \ell}^{\pm}}{{\mathit \ell}^{\mp}}$ + $\not E_T$, ${{\widetilde{\mathit \mu}}_{{L}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$> 290$ 95 1
 2019 AW
CMS ${{\mathit \ell}^{\pm}}{{\mathit \ell}^{\mp}}$ + $\not E_T$, ${{\widetilde{\mathit \ell}}_{{R}}}$ and ${{\widetilde{\mathit \ell}}}={{\widetilde{\mathit e}}}$, ${{\widetilde{\mathit \mu}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$> 400$ 95 1
 2019 AW
CMS ${{\mathit \ell}^{\pm}}{{\mathit \ell}^{\mp}}$ + $\not E_T$, ${{\widetilde{\mathit \ell}}_{{L}}}$ and ${{\widetilde{\mathit \ell}}}={{\widetilde{\mathit e}}}$, ${{\widetilde{\mathit \mu}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$> 450$ 95 1
 2019 AW
CMS ${{\mathit \ell}^{\pm}}{{\mathit \ell}^{\mp}}$ + $\not E_T$, ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{R}}}}$ = ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{L}}}}$ and ${{\widetilde{\mathit \ell}}}={{\widetilde{\mathit e}}}$, ${{\widetilde{\mathit \mu}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$> 310$ 95 1
 2019 AW
CMS ${{\mathit \ell}^{\pm}}{{\mathit \ell}^{\mp}}$ + $\not E_T$, ${\mathit m}_{{{\widetilde{\mathit \mu}}_{{R}}}}$ = ${\mathit m}_{{{\widetilde{\mathit \mu}}_{{L}}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$> 190$ 95 2
 2018 R
ATLS 2${{\mathit \ell}}$ (soft) + $\not E_T$, ${\mathit m}_{{{\widetilde{\mathit e}}}}$ = ${\mathit m}_{{{\widetilde{\mathit \mu}}}}$, ${\mathit m}_{{{\widetilde{\mathit \mu}}}}$ $−$ ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 5 GeV
3
 2014 R
CMS ${}\geq{}3{{\mathit \ell}^{\pm}}$, ${{\widetilde{\mathit \ell}}}$ $\rightarrow$ ${{\mathit \ell}^{\pm}}{{\mathit \tau}^{\mp}}{{\mathit \tau}^{\mp}}{{\widetilde{\mathit G}}}$ simplified model, GMSB, stau (N)NLSP scenario
4
 2013 B
ATLS 2${{\mathit \ell}^{\pm}}$ + $\not E_T$, SMS, pMSSM
$>91.0$ 5
 2004
OPAL $\Delta \mathit m>$3 GeV, ${{\widetilde{\mathit \mu}}_{{R+}}}{{\widetilde{\mathit \mu}}_{{R-}}}$ , $\vert {{\mathit \mu}}\vert >100~$GeV, tan $\beta$=1.5
$>86.7$ 6
 2004
L3 $\Delta \mathit m>$10 GeV, ${{\widetilde{\mathit \mu}}_{{R}}^{+}}{{\widetilde{\mathit \mu}}_{{R}}^{-}}$, $\vert {{\mathit \mu}}\vert >200~$GeV, tan $\beta {}\geq{}$2
$\text{none 30 - 88}$ 95 7
 2003 M
DLPH $\Delta {{\mathit m}}>$5~GeV, ${{\widetilde{\mathit \mu}}_{{R}}^{+}}{{\widetilde{\mathit \mu}}_{{R}}^{-}}$
$\bf{>94}$ 95 8
 2003 M
DLPH ${{\widetilde{\mathit \mu}}_{{R}}},1{}\leq{}$tan $\beta {}\leq{}$40, $\Delta {{\mathit m}}>$10~GeV
$>88$ 95 9
 2002 E
ALEP $\Delta \mathit m>15$ GeV, ${{\widetilde{\mathit \mu}}_{{R+}}}{{\widetilde{\mathit \mu}}_{{R-}}}$
• • • We do not use the following data for averages, fits, limits, etc. • • •
$> 500$ 95 10
 2018 BT
ATLS 2${{\mathit \ell}}$ + $\not E_T$, ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{R}}}}$ = ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{L}}}}$ and ${{\widetilde{\mathit \ell}}}={{\widetilde{\mathit e}}}$, ${{\widetilde{\mathit \mu}}}$, ${{\widetilde{\mathit \tau}}}$ , with ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
$\text{none 90 - 325}$ 95 11
 2014 G
ATLS ${{\widetilde{\mathit \ell}}}$ ${{\widetilde{\mathit \ell}}}$ $\rightarrow$ ${{\mathit \ell}^{+}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}{{\mathit \ell}^{-}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ , simplified model, ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{L}}}}$ = ${\mathit m}_{{{\widetilde{\mathit \ell}}_{{R}}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0 GeV
12
 2014 I
CMS ${{\widetilde{\mathit \ell}}}$ $\rightarrow$ ${{\mathit \ell}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ , simplified model
$>80$ 95 13
 2000 V
DLPH ${{\widetilde{\mathit \mu}}_{{R}}}{{\widetilde{\mathit \mu}}_{{R}}}$ ( ${{\widetilde{\mathit \mu}}_{{R}}}$ $\rightarrow$ ${{\mathit \mu}}{{\widetilde{\mathit G}}}$ ), ${\mathit m}_{{{\widetilde{\mathit G}}}}>$8 eV
1  SIRUNYAN 2019AW searched in 35.9 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for direct electroweak pair production of selectrons or smuons in events with two leptons (electrons or muons) of the opposite electric charge and same flavour, no jets and large $\not E_T$. No significant excess above the Standard Model expectations is observed. Limits are set on the selectron mass assuming left-handed, right-handed or both left- and right-handed (mass degenerate) production, see their Figure 6. Similarly, limits are set on the smuon mass, see their Figure 7. Limits are also set on slepton masses under the assumption that the selectron and smuon are mass degenerate, see their Figure 5.
2  AABOUD 2018R searched in 36.1 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for electroweak production in scenarios with compressed mass spectra in final states with two low-momentum leptons and missing transverse momentum. The data are found to be consistent with the SM prediction. Results are interpreted in slepton pair production models with a fourfold degeneracy assumed in selectron and smuon masses. The ${{\widetilde{\mathit \mu}}}$ masses are excluded up to 190 GeV for ${\mathit m}_{{{\widetilde{\mathit \mu}}}}$ $−$ ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 5 GeV. The exclusion limits extend down to mass splittings of 1 GeV, see their Fig. 11.
3  CHATRCHYAN 2014R searched in 19.5 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for events with at least three leptons (electrons, muons, taus) in the final state. No significant excess above the Standard Model expectations is observed. Limits are set on the slepton mass in a stau (N)NLSP simplified model (GMSB) where the decay ${{\widetilde{\mathit \ell}}}$ $\rightarrow$ ${{\mathit \ell}^{\pm}}{{\mathit \tau}^{\pm}}{{\mathit \tau}^{\mp}}{{\widetilde{\mathit G}}}$ takes place with a branching ratio of 100$\%$, see Fig. 8.
4  AAD 2013B searched in 4.7 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 7 TeV for sleptons decaying to a final state with two leptons (${{\mathit e}}$ and ${{\mathit \mu}}$) and missing transverse energy. No excess beyond the Standard Model expectation is observed. Limits are derived in a simplified model of direct left-handed slepton pair production, where left-handed slepton masses between 85 and 195 GeV are excluded at 95$\%$ C.L. for ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 20 GeV. See also Fig. 2(a). Exclusion limits are also derived in the phenomenological MSSM, see Fig. 3.
5  ABBIENDI 2004 search for ${{\widetilde{\mathit \mu}}_{{R}}}{{\widetilde{\mathit \mu}}_{{R}}}$ production in acoplanar di-muon final states in the $183 - 208$~GeV data. See Fig.$~$14 for the dependence of the limits on ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ and for the limit at tan $\beta$=35. Under the assumption of 100\% branching ratio for ${{\widetilde{\mathit \mu}}_{{R}}}$ $\rightarrow$ ${{\mathit \mu}}$ ~${{\widetilde{\mathit \chi}}_{{1}}^{0}}$, the limit improves to 94.0 GeV for $\Delta \mathit m>$ 4$~$GeV. See Fig.~11 for the dependence of the limits on m$_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ at several values of the branching ratio. This limit supersedes ABBIENDI 2000G.
6  ACHARD 2004 search for ${{\widetilde{\mathit \mu}}_{{R}}}{{\widetilde{\mathit \mu}}_{{R}}}$ production in acoplanar di-muon final states in the $192 - 209$ GeV data. Limits on ${\mathit m}_{{{\widetilde{\mathit \mu}}_{{R}}}}$ are derived from a scan over the MSSM parameter space with universal GUT scale gaugino and scalar masses and , 1${}\leq{}$tan $\beta {}\leq{}$60 and $-2{}\leq{}\mu {}\leq{}$2 TeV. See Fig.~4 for the dependence of the limits on ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$. This limit supersedes ACCIARRI 1999W.
7  ABDALLAH 2003M looked for acoplanar dimuon $\text{+}\not E$ final states at $\sqrt {s }$ = $189 - 208$ GeV. The limit assumes B( ${{\widetilde{\mathit \mu}}}$ $\rightarrow$ ${{\mathit \mu}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ ) = 100\%. See Fig.~16 for limits on the (${\mathit m}_{{{\widetilde{\mathit \mu}}_{{R}}}}$, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$) plane. These limits include and update the results of ABREU 2001 .
8  ABDALLAH 2003M uses data from $\sqrt {s }$ = $192 - 208$ GeV to obtain limits in the framework of the MSSM with gaugino and sfermion mass universality at the GUT scale. An indirect limit on the mass is derived by constraining the MSSM parameter space by the results from direct searches for neutralinos (including cascade decays) and for sleptons. These limits are valid for values of M$_{2}<$ 1 TeV, $\vert {{\mathit \mu}}\vert {}\leq{}$1 TeV with the ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$ as LSP. The quoted limit is obtained when there is no mixing in the third family. See Fig.~43 for the mass limits as a function of tan $\beta$. These limits update the results of ABREU 2000W.
9  HEISTER 2002E looked for acoplanar dimuon + $\not E_T$ final states from ${{\mathit e}^{+}}{{\mathit e}^{-}}$ interactions between 183 and 209 GeV. The mass limit assumes B( ${{\widetilde{\mathit \mu}}}$ $\rightarrow$ ${{\mathit \mu}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ )=1. See their Fig.$~$4 for the dependence of the limit on $\Delta \mathit m$. These limits include and update the results of BARATE 2001 .
10  AABOUD 2018BT searched in 36.1 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for direct electroweak production of charginos, chargino and next-to-lightest neutralinos and sleptons in events with two or three leptons (electrons or muons), with or without jets, and large missing transverse energy. No significant excess above the Standard Model expectations is observed. Limits are set on the slepton mass up to 500 GeV for massless ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$, assuming degeneracy of ${{\widetilde{\mathit e}}}$, ${{\widetilde{\mathit \mu}}}$, and ${{\widetilde{\mathit \tau}}}$ and exploiting the 2${{\mathit \ell}}$ signature, see their Figure 8(b).
11  AAD 2014G searched in 20.3 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for electroweak production of slepton pairs, decaying to a final sate with two leptons (${{\mathit e}}$ and ${{\mathit \mu}}$) and missing transverse momentum. No excess beyond the Standard Model expectation is observed. Exclusion limits are derived in simplified models of slepton pair production, see Fig. 8. An interpretation in the pMSSM is also given, see Fig. 10.
12  KHACHATRYAN 2014I searched in 19.5 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for electroweak production of slepton pairs decaying to a final state with opposite-sign lepton pairs (${{\mathit e}}$ or ${{\mathit \mu}}$) and missing transverse momentum. No excess beyond the Standard Model expectation is observed. Exclusion limits are derived in simplified models, see Fig. 18.
13  ABREU 2000V use data from $\sqrt {\mathit s }$= $130 - 189$ GeV to search for tracks with large impact parameter or visible decay vertices. Limits are obtained as function of ${\mathit m}_{{{\widetilde{\mathit G}}}}$, after combining these results with the search for slepton pair production in the SUGRA framework from ABREU 2001 to cover prompt decays and on stable particle searches from ABREU 2000Q. For limits at different ${\mathit m}_{{{\widetilde{\mathit G}}}}$, see their Fig.$~$12.
References:
 SIRUNYAN 2019AW
PL B790 140 Search for supersymmetric partners of electrons and muons in proton-proton collisions at $\sqrt{s}=$ 13 TeV
 AABOUD 2018BT
EPJ C78 995 Search for electroweak production of supersymmetric particles in final states with two or three leptons at $\sqrt{s}=13\,$TeV with the ATLAS detector
 AABOUD 2018R
PR D97 052010 Search for electroweak production of supersymmetric states in scenarios with compressed mass spectra at $\sqrt{s}=13$ TeV with the ATLAS detector
JHEP 1405 071 Search for Direct Production of charginos, neutralinos and sleptons in Final States with Two Leptons and Missing Transverse Momentum in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 8 TeV with the ATLAS Detector
 CHATRCHYAN 2014R
PR D90 032006 Search for Anomalous Production of Events with Three or More Leptons in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 8 TeV
 KHACHATRYAN 2014I
EPJ C74 3036 Searches for Electroweak Production of charginos, neutralinos, and sleptons Decaying to Leptons and ${{\mathit W}}$, ${{\mathit Z}}$, and Higgs Bosons in ${{\mathit p}}{{\mathit p}}$ Collisions at 8 TeV
PL B718 879 Search for Direct Slepton and Gaugino Production in Final States with Two Leptons and Missing Transverse Momentum with the ATLAS Detector in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 7 TeV
EPJ C32 453 Search for Anomalous Production of Dilepton Events with Missing Transverse Momentum in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions at $\sqrt {s }$ = $183 - 209$ GeV
EPJ C31 421 Searches for Supersymmetric Particles in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions up to 208 GeV and Interpretation of the Results within the MSSM
PL B526 206 Search for Scalar Leptons in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions at Center-of-mass Energies upto 209 GeV