# ${{\widetilde{\boldsymbol t}}}$ (Stop) mass limit

Limits depend on the decay mode. In ${{\mathit e}^{+}}{{\mathit e}^{-}}$ collisions they also depend on the mixing angle of the mass eigenstate ${{\widetilde{\mathit t}}_{{1}}}$ = ${{\widetilde{\mathit t}}_{{L}}}$cos $\theta _{\mathit t}$ $+$ ${{\widetilde{\mathit t}}_{{R}}}$sin$\theta _{\mathit t}$. The coupling to the ${{\mathit Z}}$ vanishes when $\theta _{\mathit t}$ = $0.98$. In the Listings below, we use $\Delta \mathit m$ ${}\equiv$ ${\mathit m}_{{{\widetilde{\mathit t}}_{{1}}}}–{\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ or $\Delta \mathit m$ ${}\equiv$ ${\mathit m}_{{{\widetilde{\mathit t}}_{{1}}}}–{\mathit m}_{{{\widetilde{\mathit \nu}}}}$, depending on relevant decay mode. See also bounds in ${{\widetilde{\mathit q}}}~$(Squark) MASS LIMIT.''
Some earlier papers are now obsolete and have been omitted. They were last listed in our PDG 2014 edition: K. Olive, $\mathit et~al.$ (Particle Data Group), Chinese Physics C38 070001 (2014) (http://pdg.lbl.gov).

# R-parity violating ${{\widetilde{\boldsymbol t}}}$ (Stop) mass limit INSPIRE search

VALUE (GeV) CL% DOCUMENT ID TECN  COMMENT
$> 1150$ 95 1
 2019 BI
ATLS ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit \mu}}$ , long-lived, Tstop2RPV, c$\tau$ = 0.1 cm
$\bf{> 1100}$ 95 2
 2019 BJ
CMS ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit e}}$ , Tstop2RPV, prompt
$\text{none 100 - 410}$ 95 3
 2018 BB
ATLS 4 jets, Tstop1RPV with ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit d}}{{\mathit s}}$ , ${{\mathit \lambda}_{{312}}^{''}}$ coupling
$\text{none 100 - 470, 480 - 610}$ 95 4
 2018 BB
ATLS 4 jets, Tstop1RPV, ${{\mathit \lambda}_{{323}}^{''}}$ coupling
${}\geq{}\text{ 600 - 1500}$ 95 5
 2018 P
ATLS 2${{\mathit \ell}}$ + ${{\mathit b}}$-jets, Tstop2RPV, depending on ${{\mathit \lambda}_{{i33}}^{\,'}}$ coupling (${{\mathit i}}$ = 1, 2, 3)
$\bf{> 1130}$ 95 6
CMS ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit \ell}}$ , long-lived, c$\tau$ = $70 - 100$ mm
$> 550$ 95 6
CMS ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit \ell}}$ , long-lived, c$\tau$ = $1 - 1000$ mm
$> 1400$ 95 7
 2018 DV
CMS long-lived ${{\widetilde{\mathit t}}}$, RPV, ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\overline{\mathit d}}}{{\overline{\mathit d}}}$ , 0.6 mm $<$ c${{\mathit \tau}}<$ 80 mm
$\text{none 80 - 520}$ 95 8
 2018 DY
CMS 2, 4 jets, Tstop3RPV, ${{\mathit \lambda}_{{312}}^{''}}$ coupling
$\text{none 80 - 270, 285 - 340, 400 - 525}$ 95 8
 2018 DY
CMS 2 , 4 jets, Tstop1RPV, ${{\mathit \lambda}_{{323}}^{''}}$ coupling
$>1200$ 95 9
 2017 AI
ATLS ${}\geq{}1{{\mathit \ell}}$+ ${}\geq{}$8 jets, Tstop1 with ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$ $\rightarrow$ ${{\mathit t}}{{\mathit b}}{{\mathit s}}$ , ${{\mathit \lambda}_{{323}}^{''}}$ coupling, ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$=500 GeV
$\text{none, 100 - 315}$ 95 10
 2016 AM
• • • We do not use the following data for averages, fits, limits, etc. • • •
$>890$ 95 11
 2016 AC
CMS ${{\mathit e}^{+}}{{\mathit e}^{-}}$ + ${}\geq{}$5 jets; ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ ; ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ $\rightarrow$ ${{\mathit \ell}^{\pm}}$ ${{\mathit j}}{{\mathit j}}$ , ${{\mathit \lambda}_{{ijk}}^{\,'}}$
$> 1000$ 95 11
 2016 AC
CMS ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ + ${}\geq{}$5 jets; ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ ; ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ $\rightarrow$ ${{\mathit \ell}^{\pm}}$ ${{\mathit j}}{{\mathit j}}$ , ${{\mathit \lambda}_{{ijk}}^{\,'}}$
$> 950$ 95 12
 2016 BX
CMS ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit t}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ , ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$ $\rightarrow$ ${{\mathit \ell}}{{\mathit \ell}}{{\mathit \nu}}$ , ${{\mathit \lambda}_{{121}}}$ or ${{\mathit \lambda}_{{122}}}{}\not=$0
$>790$ 95 13
 2015 E
CMS ${{\widetilde{\mathit t}}_{{1}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit \ell}}$ , c$\tau$ = 2 cm
1  SIRUNYAN 2019BI searched in 35.9 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV in final states with two muons and two jets, or with one muon, two jets, and missing transverse momentum. Limits are set in a model of pair-produced, prompt or long-lived top squarks with R-parity violating decays to a ${{\mathit b}}$-quark and a lepton (Tstop2RPV), branching fraction of ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit \mu}}$ equal to 1/3 and c$\tau$ between 0.1 cm and 10 cm in the case of long-lived top squarks. See their Fig. 10.
2  SIRUNYAN 2019BJ searched in 35.9 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV in final states with two electrons and two jets, or with one electron, two jets, and missing transverse momentum. Limits are set in a model of pair-produced, prompt top squarks with R-parity violating decays to a ${{\mathit b}}$-quark and a lepton (Tstop2RPV), assuming branching fraction of ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\mathit e}}$ equal to 1/3 and c$\tau$ = 0 cm. See their Fig.10.
3  AABOUD 2018BB searched in 36.7 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for massive colored resonances which are pair-produced and decay into two jets. No significant deviation from the background prediction is observed. Results are interpreted in a SUSY simplified model as Tstop1RPV with ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit d}}{{\mathit s}}$ . Top squarks with masses in the range $100 - 410$ GeV are excluded, see their Figure 9(a). The ${{\mathit \lambda}_{{312}}^{''}}$ coupling is assumed to be sufficiently large for the decays to be prompt, but small enough to neglect the single-top-squark resonant production through RPV couplings.
4  AABOUD 2018BB searched in 36.7 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for massive coloured resonances which are pair-produced and decay into two jets. No significant deviation from the background prediction is observed. Results are interpreted in Tstop1RPV. Top squarks with masses in the range $100 - 470$ GeV or $480 - 610$ GeV are excluded, see their Figure 9(b). The ${{\mathit \lambda}_{{323}}^{''}}$ coupling is assumed to be sufficiently large for the decays to be prompt, but small enough to neglect the single-top-squark resonant production through RPV couplings.
5  AABOUD 2018P searched in 36.1 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for pair-produced top squarks that decay through RPV ${{\mathit \lambda}_{{i33}}^{\,'}}$ (${{\mathit i}}$ = 1, 2, 3) couplings to a final state with two leptons and two jets, at least one of which is identified as a ${{\mathit b}}$-jet. No significant excess is observed over the SM background. In the Tstop2RPV model, lower limits on the top squark masses between 600 and 1500 GeV are set depending on the branching fraction to ${{\mathit b}}{{\mathit e}}$ , ${{\mathit b}}{{\mathit \mu}}$ , and ${{\mathit b}}{{\mathit \tau}}$ final states. See their Figs 6 and 7.
6  SIRUNYAN 2018AD searched in 2.6 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for long-lived particles by exploiting the multiplicity of displaced jets to search for the presence of signal decays occurring at distances between 1 and 1000 mm. Limits are set in a model of pair-produced, long-lived top squarks with R-parity violating decays to a ${{\mathit b}}$-quark and a lepton, see their Figure 3.
7  SIRUNYAN 2018DV searched in 38.5 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for long-lived particles in events with multiple jets and two displaced vertices composed of many tracks. No events with two well-separated high-track-multiplicity vertices were observed. Limits are set on the stop and the gluino mass in RPV models of supersymmetry where the stop (gluino) is decaying solely into dijet (multijet) final states, see their Figures 6 and 7.
8  SIRUNYAN 2018DY searched in 35.9 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for the pair production of resonances, each decaying to two quarks. The search is conducted separately in a boosted (two-jet) and resolved (four-jet) jet topology. The mass spectra are found to be consistent with the Standard Model expectations. Limits are set on the stop mass in the Tstop3RPV and Tstop1RPV simplified models, see their Figure 11.
9  AABOUD 2017AI searched in 36.1 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 13 TeV for events with one or more isolated lepton, at least eight jets, either zero or many ${{\mathit b}}$-jets, for evidence of R-parity violating decays of the top squark. No significant excess above the Standard Model expectations is observed. Limits up to 1.25 (1.10) TeV are set on the top squark mass in R-parity-violating supersymmetry models where ${{\widetilde{\mathit t}}_{{1}}}$ decays for a bino LSP as: ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit t}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ and for a higgsino LSP as ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit t}}{{\widetilde{\mathit \chi}}_{{1,2}}^{0}}$ / ${{\mathit b}}{{\widetilde{\mathit \chi}}_{{1}}^{+}}$ . These is followed by the decays through the non-zero ${{\mathit \lambda}_{{323}}^{''}}$ coupling ${{\widetilde{\mathit \chi}}_{{1,2}}^{0}}$ $\rightarrow$ ${{\mathit t}}{{\mathit b}}{{\mathit s}}$ , ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ $\rightarrow$ ${{\mathit b}}{{\mathit b}}{{\mathit s}}$ . See their Figure 10 and text for details on model assumptions.
10  AAD 2016AM searched in 17.4 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for events containing two large-radius hadronic jets. No deviation from the background prediction is observed. Top squarks with masses between 100 and 315 GeV are excluded at 95$\%$ C.L. in the hypothesis that they both decay via ${{\mathit R}}$ -parity violating coupling ${{\mathit \lambda}_{{323}}^{"}}$ to ${{\mathit b}}$- and ${{\mathit s}}$-quarks. See their Fig. 10.
11  KHACHATRYAN 2016AC searched in 19.7 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for events with low missing transverse momentum, two oppositely charged electrons or muons, and at least five jets, at least one of which is a ${{\mathit b}}$-jet, for evidence of R-parity violating, charging-mediated decays of the top squark. No significant excess above the Standard Model expectations is observed. Limits are set on the stop mass in R-parity-violating supersymmetry models where ${{\widetilde{\mathit t}}}$ $\rightarrow$ ${{\mathit b}}{{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ with ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ $\rightarrow$ ${{\mathit \ell}^{\pm}}{{\mathit j}}{{\mathit j}}$ , ${{\mathit \lambda}_{{ijk}}^{\,'}}$ ${}\not=$ 0 (${{\mathit i}},{{\mathit j}}$, ${{\mathit k}}{}\leq{}$ 2), and with ${\mathit m}_{{{\widetilde{\mathit t}}}}$ $−$ ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{\pm}}}$ = 100 GeV, see Fig. 3.
12  KHACHATRYAN 2016BX searched in 19.5 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for events containing 4 leptons coming from R-parity-violating decays of ${{\widetilde{\mathit \chi}}_{{1}}^{0}}$ $\rightarrow$ ${{\mathit \ell}}{{\mathit \ell}}{{\mathit \nu}}$ with ${{\mathit \lambda}_{{121}}}{}\not=$ 0 or ${{\mathit \lambda}_{{122}}}{}\not=$ 0. No excess over the expected background is observed. Limits are derived on the gluino, squark and stop masses, see Fig. 23.
13  KHACHATRYAN 2015E searched for long-lived particles decaying to leptons in 19.7 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV. Events were selected with an electron and muon with opposite charges and each with transverse impact parameter values between 0.02 and 2 cm. Limits are set on SUSY benchmark models with pair production of top squarks decaying into an ${{\mathit e}}{{\mathit \mu}}$ final state via RPV interactions. See their Fig. 2
References:
 SIRUNYAN 2019BJ
PR D99 052002 Search for pair production of first-generation scalar leptoquarks at $\sqrt{s} =$ 13 TeV
 SIRUNYAN 2019BI
PR D99 032014 Search for pair production of second-generation leptoquarks at $\sqrt{s}=$ 13 TeV
 AABOUD 2018BB
EPJ C78 250 A search for pair-produced resonances in four-jet final states at $\sqrt{s} =$ 13 TeV with the ATLAS detector
 AABOUD 2018P
PR D97 032003 Search for B-L R -parity-violating top squarks in $\sqrt s$ =13??TeV pp collisions with the ATLAS experiment
PL B780 432 Search for new long-lived particles at $\sqrt{s} =$ 13 TeV
 SIRUNYAN 2018DV
PR D98 092011 Search for long-lived particles with displaced vertices in multijet events in proton-proton collisions at $\sqrt{s}=$13 TeV
 SIRUNYAN 2018DY
PR D98 112014 Search for pair-produced resonances decaying to quark pairs in proton-proton collisions at $\sqrt{s}=$ 13 TeV
 AABOUD 2017AI
JHEP 1709 088 Search for New Phenomena in a Lepton Plus High Jet Multiplicity Final State with the ATLAS Experiment using $\sqrt {s }$ = 13 TeV Proton-Proton Collision Data
JHEP 1606 067 A Search for Top squarks with R-parity-violating Decays to All-hadronic Final States with the ATLAS Detector in $\sqrt {s }$ = 8 TeV Proton-Proton Collisions
PL B760 178 Search for ${{\mathit R}}$ -Parity Violating Decays of a top squark in Proton-Proton Collisions at $\sqrt {s }$ = 8 TeV
PR D94 112009 Searches for $\mathit R$-Parity-Violating Supersymmetry in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 8 TeV in Final States with $0 - 4$ Leptons