# Long-lived ${{\widetilde{\boldsymbol \chi}}^{\pm}}$ (Chargino) mass limit INSPIRE search

Limits on charginos which leave the detector before decaying.
VALUE (GeV) CL% DOCUMENT ID TECN  COMMENT
$\bf{>620}$ 95 1
 2015 AE
ATLS stable ${{\widetilde{\mathit \chi}}^{\pm}}$
$>534$ 95 2
 2015 BM
ATLS stable ${{\widetilde{\mathit \chi}}^{\pm}}$
$>239$ 95 2
 2015 BM
ATLS ${{\widetilde{\mathit \chi}}^{\pm}}$ $\rightarrow$ ${{\widetilde{\mathit \chi}}_{{1}}^{0}}{{\mathit \pi}^{\pm}}$ , lifetime 1 ns, ${\mathit m}_{{{\widetilde{\mathit \chi}}^{\pm}}}$ $−$ ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0.14 GeV
$>482$ 95 2
 2015 BM
ATLS ${{\widetilde{\mathit \chi}}^{\pm}}$ $\rightarrow$ ${{\widetilde{\mathit \chi}}_{{1}}^{0}}{{\mathit \pi}^{\pm}}$ , lifetime 15 ns, ${\mathit m}_{{{\widetilde{\mathit \chi}}^{\pm}}}$ $−$ ${\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 0.14 GeV
$> 103$ 95 3
 2013 H
ATLS long-lived ${{\widetilde{\mathit \chi}}^{\pm}}$ $\rightarrow$ ${{\widetilde{\mathit \chi}}_{{1}}^{0}}{{\mathit \pi}^{\pm}}$ , mAMSB, $\Delta {\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ = 160 MeV
$> 92$ 95 4
 2012 BJ
ATLS long-lived ${{\widetilde{\mathit \chi}}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\widetilde{\mathit \chi}}_{{1}}^{0}}$ , mAMSB
$> 171$ 95 5
 2009 M
D0 ${{\widetilde{\mathit H}}}$
$>102$ 95 6
 2003 L
OPAL ${\mathit m}_{{{\widetilde{\mathit \nu}}}}>$500~GeV
$\text{none 2 - 93.0}$ 95 7
 2000 T
DLPH ${{\widetilde{\mathit H}}^{\pm}}$ or ${\mathit m}_{{{\widetilde{\mathit \nu}}}}>{\mathit m}_{{{\widetilde{\mathit \chi}}^{\pm}}}$
• • • We do not use the following data for averages, fits, limits, etc. • • •
$>260$ 95 8
 2015 AB
CMS ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ $\rightarrow$ ${{\widetilde{\mathit \chi}}_{{1}}^{0}}{{\mathit \pi}^{\pm}}$ ,$\tau _{{{\widetilde{\mathit \chi}}_{{1}}^{\pm}}}$=0.2ns, AMSB
$>800$ 95 9
 2015 AO
CMS long-lived ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$, mAMSB, $\tau >$100ns
$>100$ 95 9
 2015 AO
CMS long-lived ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$, mAMSB, $\tau$ $>$ 3 ns
95 10
 2015 W
CMS long-lived ${{\widetilde{\mathit \chi}}^{0}}$, ${{\widetilde{\mathit q}}}$ $\rightarrow$ ${{\mathit q}}{{\widetilde{\mathit \chi}}^{0}}$ , ${{\widetilde{\mathit \chi}}^{0}}$ $\rightarrow$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}{{\mathit \nu}}$ , RPV
$> 270$ 95 11
 2013 BD
ATLS disappearing-track signature, AMSB
$> 278$ 95 12
 2013 B
D0 long-lived ${{\widetilde{\mathit \chi}}^{\pm}}$, gaugino-like
$> 244$ 95 12
 2013 B
D0 long-lived ${{\widetilde{\mathit \chi}}^{\pm}}$, higgsino-like
1  AAD 2015AE searched in 19.1 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for heavy long-lived charged particles, measured through their specific ionization energy loss in the ATLAS pixel detector or their time-of-flight in the ALTAS muon system. In the absence of an excess of events above the expected backgrounds, limits are set on stable charginos, see Fig. 10.
2  AAD 2015BM searched in 18.4 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for stable and metastable non-relativistic charged particles through their anomalous specific ionization energy loss in the ATLAS pixel detector. In absence of an excess of events above the expected backgrounds, limits are set on stable charginos (see Table 5) and on metastable charginos decaying to ${{\widetilde{\mathit \chi}}_{{1}}^{0}}{{\mathit \pi}^{\pm}}$ , see Fig. 11.
3  AAD 2013H searched in 4.7 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 7 TeV for direct electroweak production of long-lived charginos in the context of AMSB scenarios. The search is based on the signature of a high-momentum isolated track with few associated hits in the outer part of the tracking system, arising from a chargino decay into a neutralino and a low-momentum pion. The $p_T$ spectrum of the tracks was found to be consistent with the SM expectations. Constraints on the lifetime and the production cross section were obtained, see Fig. 6. In the minimal AMSB framework with tan $\beta$ = 5, and ${{\mathit \mu}}$ $>$ 0, a chargino having a mass below 103 (85) GeV for a chargino-neutralino mass splitting $\Delta {\mathit m}_{{{\widetilde{\mathit \chi}}_{{1}}^{0}}}$ of 160 (170) MeV is excluded at the 95$\%$ C.L. See Fig. 7 for more precise bounds.
4  AAD 2012BJ looked in 1.02 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 7 TeV for signatures of decaying charginos resulting in isolated tracks with few associated hits in the outer region of the tracking system. The $p_T$ spectrum of the tracks was found to be consistent with the SM expectations. Constraints on the lifetime and the production cross section were obtained. In the minimal AMSB framework with ${\mathit m}_{\mathrm {3/2}}$ $<$ 32 TeV, ${\mathit m}_{\mathrm {0}}$ $<$ 1.5 TeV, tan ${{\mathit \beta}}$ = 5, and ${{\mathit \mu}}$ $>$ 0, a chargino having a mass below 92 GeV and a lifetime between 0.5 ns and 2 ns is excluded at the 95$\%$ C.L. See their Fig. 8 for more precise bounds.
5  ABAZOV 2009M searched in 1.1 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\sqrt {s }$ = 1.96 TeV for events with direct production of a pair of charged massive stable particles identified by their TOF. The number of the observed events is consistent with the predicted background. The data are used to constrain the production cross section as a function of the ${{\widetilde{\mathit \chi}}_{{1}}^{\pm}}$ mass, see their Fig. 2. The quoted limit improves to 206 GeV for gaugino-like charginos.
6  ABBIENDI 2003L used ${{\mathit e}^{+}}{{\mathit e}^{-}}$ data at $\sqrt {s }$ = $130 - 209$ GeV to select events with two high momentum tracks with anomalous dE/dx. The excluded cross section is compared to the theoretical expectation as a function of the heavy particle mass in their Fig.~3. The bounds are valid for colorless fermions with lifetime longer than $10^{-6}$ s. Supersedes the results from ACKERSTAFF 1998P.
7  ABREU 2000T searches for the production of heavy stable charged particles, identified by their ionization or Cherenkov radiation, using data from $\sqrt {\mathit s }$= 130 to 189 GeV. These limits include and update the results of ABREU 1998P.
8  KHACHATRYAN 2015AB searched in 19.5 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for events containing tracks with little or no associated calorimeter energy deposits and with missing hits in the outer layers of the tracking system (disappearing-track signature). Such disappearing tracks can result from the decay of charginos that are nearly mass degenerate with the lightest neutralino. The number of observed events is in agreement with the background expectation. Limits are set on the cross section of electroweak chargino production in terms of the chargino mass and mean proper lifetime, see Fig. 4. In the minimal AMSB model, a chargino mass below 260 GeV is excluded at 95$\%$ C.L., see their Fig. 5.
9  KHACHATRYAN 2015O searched in 18.8 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for evidence of long-lived charginos in the context of AMSB and pMSSM scenarios. The results are based on a previously published search for heavy stable charged particles at 7 and 8 TeV. In the minimal AMSB framework with tan ${{\mathit \beta}}$ = 5 and $\mathit \mu$ ${}\geq{}$ 0, constraints on the chargino mass and lifetime were placed, see Fig. 5. Charginos with a mass below 800 (100) GeV are excluded at the 95$\%$ C.L. for lifetimes above 100 ns (3 ns). Constraints are also placed on the pMSSM parameter space, see Fig. 3.
10  KHACHATRYAN 2015W searched in up to 20.5 ${\mathrm {fb}}{}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for evidence of long-lived neutralinos produced through ${{\widetilde{\mathit q}}}$-pair production, with ${{\widetilde{\mathit q}}}$ $\rightarrow$ ${{\mathit q}}{{\widetilde{\mathit \chi}}^{0}}$ and ${{\widetilde{\mathit \chi}}^{0}}$ $\rightarrow$ ${{\mathit \ell}^{+}}{{\mathit \ell}^{-}}{{\mathit \nu}}$ (RPV: $\lambda _{121}$, $\lambda _{122}{}\not=$ 0). 95$\%$ C.L. exclusion limits on cross section times branching ratio are set as a function of mean proper decay length of the neutralino, see Figs. 6 and 9.
11  AAD 2013BD searched in 20.3 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ collisions at $\sqrt {s }$ = 8 TeV for events containing tracks with no associated hits in the outer region of the tracking system resulting from the decay of charginos that are nearly mass degenerate with the lightest neutralino, as is often the case in AMSB scenarios. No significant excess above the background expectation is observed for candidate tracks with large transverse momentum. Constraints on chargino properties are obtained and in the minimal AMSB model, a chargino mass below 270$~$GeV is excluded at 95$\%$ C.L., see their Fig. 7.
12  ABAZOV 2013B looked in 6.3 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ collisions at $\sqrt {s }$ = 1.96 TeV for charged massive long-lived particles in events with muon-like particles that have both speed and ionization energy loss inconsistent with muons produced in beam collisions. In the absence of an excess, limits are set at 95$\%$ C.L. on gaugino- and higgsino-like charginos, see their Table 20 and Fig. 23.
References:
EPJ C75 407 Search for Metastable Heavy Charged Particles with Large Ionisation Energy Loss in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 8 TeV using the ATLAS Experiment
JHEP 1501 068 Searches for Heavy Long-Lived Charged Particles with the ATLAS Detector in Proton-Proton Collisions at $\sqrt {s }$ = 8 TeV
 KHACHATRYAN 2015AB
JHEP 1501 096 Search for Disappearing Tracks in Proton-Proton Collisions at $\sqrt {s }$ = 8 TeV
 KHACHATRYAN 2015AO
EPJ C75 325 Constraints on the pMSSM, AMSB Model and on Other Models from the Search for Long-Lived Charged Particles in Proton-Proton Collisions at $\sqrt {s }$ = 8 TeV
 KHACHATRYAN 2015W
PR D91 052012 Search for Long-Lived Particles that Decay into Final States Containing Two Electrons or Two Muons in Proton-Proton Collisions at $\sqrt {s }$ = 8 TeV
PR D88 112006 Search for Charginos Nearly Mass Degenerate with the Lightest Neutralino Based on a Disappearing-Track Signature in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 8 TeV with the ATLAS Detector
JHEP 1301 131 Search for Direct Chargino Production in Anomaly-Mediated Supersymmetry Breaking Models Based on a Disappearing-Track Signature in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 7 TeV with the ATLAS Detector
 ABAZOV 2013B
PR D87 052011 Search for Charged Massive Long-Lived Particles at $\sqrt {s }$ = 1.96 TeV
EPJ C72 1993 Search for Anomaly-Mediated Supersymmetry Breaking with the ATLAS Detector Based on a Disappearing-Track Signature in ${{\mathit p}}{{\mathit p}}$ Collisions at $\sqrt {s }$ = 7 TeV
PRL 102 161802 Search for Long-Lived Charged Massive Particles with the ${D0}$ Detector
PL B572 8 Search for Stable and Longlived Massive Charged Particles in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions at $\sqrt {s }$ = 130 to 209 GeV
PL B444 491 A Search for Heavy Stable and Longlived Squarks and Sleptons in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions at Energies from 130 to 183 GeV
PL B433 195 Search for Stable and Longlived Massive Charged Particles with the OPAL Detector at LEP in ${{\mathit e}^{+}}{{\mathit e}^{-}}$ Collisions at $\sqrt {s }$ = 13
PL B748 255 Search for Narrow High-Mass Resonances in Proton$−$Proton Collisions at$\sqrt {s }$ = 8 TeV Decaying to a ${{\mathit Z}}$ and a Higgs Boson