Search for bottom-squark pair production in $pp$ collision events at $\sqrt{s} = 13$ TeV with hadronically decaying $\tau$-leptons, $b$-jets and missing transverse momentum using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Brad ; et al.
Phys.Rev.D 104 (2021) 032014, 2021.
Inspire Record 1851675 DOI 10.17182/hepdata.99788

A search for pair production of bottom squarks in events with hadronically decaying $\tau$-leptons, $b$-tagged jets and large missing transverse momentum is presented. The analyzed dataset is based on proton-proton collisions at $\sqrt{s}$ = 13 TeV delivered by the Large Hadron Collider and recorded by the ATLAS detector from 2015 to 2018, and corresponds to an integrated luminosity of 139 fb$^{-1}$. The observed data are compatible with the expected Standard Model background. Results are interpreted in a simplified model where each bottom squark is assumed to decay into the second-lightest neutralino $\tilde \chi_2^0$ and a bottom quark, with $\tilde \chi_2^0$ decaying into a Higgs boson and the lightest neutralino $\tilde \chi_1^0$. The search focuses on final states where at least one Higgs boson decays into a pair of hadronically decaying $\tau$-leptons. This allows the acceptance and thus the sensitivity to be significantly improved relative to the previous results at low masses of the $\tilde \chi_2^0$, where bottom-squark masses up to 850 GeV are excluded at the 95% confidence level, assuming a mass difference of 130 GeV between $\tilde \chi_2^0$ and $\tilde \chi_1^0$. Model-independent upper limits are also set on the cross section of processes beyond the Standard Model.

15 data tables

The expected exclusion contour at $95\%$ CL as a function of the M(Sbottom) vs. M(N2) with the $\Delta M$(N2,N1) = 130 GeV. Masses within the contour are excluded.

The observed exclusion contour at $95\%$ CL as a function of the M(Sbottom) vs. M(N2) with the $\Delta M$(N2,N1) = 130 GeV. Masses within the contour are excluded.

Acceptance in the Single-bin SR as a function of the M(Sbottom) vs. M(N2) with the $\Delta M$(N2,N1) = 130 GeV. Keep in mind that the acceptance is given in units of $10^{-4}$.

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Search for dark matter and other new phenomena in events with an energetic jet and large missing transverse momentum using the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
JHEP 01 (2018) 126, 2018.
Inspire Record 1635274 DOI 10.17182/hepdata.80608

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses proton--proton collision data corresponding to an integrated luminosity of 36.1 fb${}^{-1}$ at a centre-of-mass energy of 13 TeV collected in 2015 and 2016 with the ATLAS detector at the Large Hadron Collider. Events are required to have at least one jet with a transverse momentum above 250 GeV and no leptons ($e$ or $\mu$). Several signal regions are considered with increasing requirements on the missing transverse momentum above 250 GeV. Good agreement is observed between the number of events in data and Standard Model predictions. The results are translated into exclusion limits in models with pair-produced weakly interacting dark-matter candidates, large extra spatial dimensions, and supersymmetric particles in several compressed scenarios.

33 data tables

The measured leading jet $p_{T}$ distribution in the W($\rightarrow \mu \nu$)+jets control region, for the $E_{T}^{miss}$ > 250GeV inclusive selection, compared to the background predictions. The latter include the global normalization factors extracted from the fit. The last bin of the distribution contains overflows.

The measured $E_{T}^{miss}$ distribution in the W($\rightarrow e \nu$)+jets control region, for the $E_{T}^{miss}$ > 250GeV inclusive selection, compared to the background predictions. The latter include the global normalization factors extracted from the fit. The last bin of the distribution contains overflows.

The measured leading jet $p_{T}$ distribution in the W($\rightarrow e \nu$)+jets control region, for the $E_{T}^{miss}$ > 250GeV inclusive selection, compared to the background predictions. The latter include the global normalization factors extracted from the fit. The last bin of the distribution contains overflows.

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Version 2
Search for supersymmetry in events with $b$-tagged jets and missing transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
JHEP 11 (2017) 195, 2017.
Inspire Record 1620694 DOI 10.17182/hepdata.79165

A search for the supersymmetric partners of the Standard Model bottom and top quarks is presented. The search uses 36.1 fb$^{-1}$ of $pp$ collision data at $\sqrt{s}=13$ TeV collected by the ATLAS experiment at the Large Hadron Collider. Direct production of pairs of bottom and top squarks ($\tilde{b}_{1}$ and $\tilde{t}_{1}$) is searched for in final states with $b$-tagged jets and missing transverse momentum. Distinctive selections are defined with either no charged leptons (electrons or muons) in the final state, or one charged lepton. The zero-lepton selection targets models in which the $\tilde{b}_{1}$ is the lightest squark and decays via $\tilde{b}_{1} \rightarrow b \tilde{\chi}^{0}_{1}$, where $\tilde{\chi}^{0}_{1}$ is the lightest neutralino. The one-lepton final state targets models where bottom or top squarks are produced and can decay into multiple channels, $\tilde{b}_{1} \rightarrow b \tilde{\chi}^{0}_{1}$ and $\tilde{b}_{1} \rightarrow t \tilde{\chi}^{\pm}_{1}$, or $\tilde{t}_{1} \rightarrow t \tilde{\chi}^{0}_{1}$ and $\tilde{t}_{1} \rightarrow b \tilde{\chi}^{\pm}_{1}$, where $\tilde{\chi}^{\pm}_{1}$ is the lightest chargino and the mass difference $m_{\tilde{\chi}^{\pm}_{1}}- m_{\tilde{\chi}^{0}_{1}}$ is set to 1 GeV. No excess above the expected Standard Model background is observed. Exclusion limits at 95\% confidence level on the mass of third-generation squarks are derived in various supersymmetry-inspired simplified models.

202 data tables

- - - - - - - - - - - - - - - - - - - - <br/><b>Acceptance:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Acceptance1">b0L-SRA350</a> <a href="79165?version=1&table=Acceptance2">b0L-SRA450</a> <a href="79165?version=1&table=Acceptance3">b0L-SRA550</a> <a href="79165?version=1&table=Acceptance4">b0L-SRB</a> <a href="79165?version=1&table=Acceptance5">b0L-SRC</a> <a href="79165?version=1&table=Acceptance6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Acceptance7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Acceptance8">b1L-SRA450</a> <a href="79165?version=1&table=Acceptance9">b1L-SRA600</a> <a href="79165?version=1&table=Acceptance10">b1L-SRA750</a> <a href="79165?version=1&table=Acceptance11">b1L-SRB</a> <a href="79165?version=1&table=Acceptance12">b1L-best</a><br/><br/><b>Efficiency:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Efficiency1">b0L-SRA350</a> <a href="79165?version=1&table=Efficiency2">b0L-SRA450</a> <a href="79165?version=1&table=Efficiency3">b0L-SRA550</a> <a href="79165?version=1&table=Efficiency4">b0L-SRB</a> <a href="79165?version=1&table=Efficiency5">b0L-SRC</a> <a href="79165?version=1&table=Efficiency6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Efficiency7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Efficiency8">b1L-SRA450</a> <a href="79165?version=1&table=Efficiency9">b1L-SRA600</a> <a href="79165?version=1&table=Efficiency10">b1L-SRA750</a> <a href="79165?version=1&table=Efficiency11">b1L-SRB</a> <a href="79165?version=1&table=Efficiency12">b1L-best</a><br/><br/><b>Best SR Mapping:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=BestSR4">b0L</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=BestSR1">b1L</a> <a href="79165?version=1&table=BestSR2">b0L</a> <a href="79165?version=1&table=BestSR3">combined</a><br/><br/><b>Exclusion Contour:</b><br/><i>symmetric:</i> b0L-SRA350&nbsp;<a href="79165?version=1&table=Contour1">exp</a>&nbsp;<a href="79165?version=1&table=Contour2">obs</a> b0L-SRA450&nbsp;<a href="79165?version=1&table=Contour5">exp</a>&nbsp;<a href="79165?version=1&table=Contour6">obs</a> b0L-SRA550&nbsp;<a href="79165?version=1&table=Contour9">exp</a>&nbsp;<a href="79165?version=1&table=Contour10">obs</a> b0L-SRB&nbsp;<a href="79165?version=1&table=Contour11">exp</a>&nbsp;<a href="79165?version=1&table=Contour12">obs</a> b0L-SRC&nbsp;<a href="79165?version=1&table=Contour15">exp</a>&nbsp;<a href="79165?version=1&table=Contour16">obs</a> b0L-best&nbsp;<a href="79165?version=1&table=Contour17">exp</a>&nbsp;<a href="79165?version=1&table=Contour18">obs</a><br/><i>asymmetric:</i> b0L-SRA350&nbsp;<a href="79165?version=1&table=Contour3">exp</a>&nbsp;<a href="79165?version=1&table=Contour4">obs</a> b0L-SRA450&nbsp;<a href="79165?version=1&table=Contour7">exp</a>&nbsp;<a href="79165?version=1&table=Contour8">obs</a> b0L-SRB&nbsp;<a href="79165?version=1&table=Contour13">exp</a>&nbsp;<a href="79165?version=1&table=Contour14">obs</a> b0L-best&nbsp;<a href="79165?version=1&table=Contour19">exp</a>&nbsp;<a href="79165?version=1&table=Contour20">obs</a> b1L-SRA300-2j&nbsp;<a href="79165?version=1&table=Contour21">exp</a>&nbsp;<a href="79165?version=1&table=Contour22">obs</a> b1L-SRA450&nbsp;<a href="79165?version=1&table=Contour23">exp</a>&nbsp;<a href="79165?version=1&table=Contour24">obs</a> b1L-SRA600&nbsp;<a href="79165?version=1&table=Contour25">exp</a>&nbsp;<a href="79165?version=1&table=Contour26">obs</a> b1L-SRA750&nbsp;<a href="79165?version=1&table=Contour27">exp</a>&nbsp;<a href="79165?version=1&table=Contour28">obs</a> b1L-SRB&nbsp;<a href="79165?version=1&table=Contour29">exp</a>&nbsp;<a href="79165?version=1&table=Contour30">obs</a> b1L-best&nbsp;<a href="79165?version=1&table=Contour31">exp</a>&nbsp;<a href="79165?version=1&table=Contour32">obs</a> A-LowMass&nbsp;<a href="79165?version=1&table=Contour33">exp</a>&nbsp;<a href="79165?version=1&table=Contour34">obs</a> A-HighMass&nbsp;<a href="79165?version=1&table=Contour35">exp</a>&nbsp;<a href="79165?version=1&table=Contour36">obs</a> B combination&nbsp;<a href="79165?version=1&table=Contour37">exp</a>&nbsp;<a href="79165?version=1&table=Contour38">obs</a> Best combination&nbsp;<a href="79165?version=1&table=Contour39">exp</a>&nbsp;<a href="79165?version=1&table=Contour40">obs</a><br/><br/><b>SR Distribution:</b><br/><a href="79165?version=1&table=SRdistribution1">b0L-SRA</a>: $m_{\mathrm{CT}}$ <a href="79165?version=1&table=SRdistribution2">b0L-SRB</a>: $\mathrm{min[m_{T}(jet_{1-4}, E_{T}^{miss})]}$ <a href="79165?version=1&table=SRdistribution3">b0L-SRC</a>: ${\cal A}$ <a href="79165?version=1&table=SRdistribution4">b1L-SRA300-2j</a>: $\mathrm{m_{bb}}$ <a href="79165?version=1&table=SRdistribution5">b1L-SRA</a>: $\mathrm{m_{eff}}$ <a href="79165?version=1&table=SRdistribution6">b1L-SRB</a>: $\mathrm{m_{T}}$<br/><br/><b>Cross section upper limit:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Limitoncrosssection1">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection2">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection3">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection4">b0L-SRA550</a> <a href="79165?version=1&table=Limitoncrosssection5">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection6">b0L-SRC</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Limitoncrosssection7">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection8">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection9">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection10">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection11">b1L-best</a> <a href="79165?version=1&table=Limitoncrosssection12">b1L-SRA300-2j</a> <a href="79165?version=1&table=Limitoncrosssection13">b1L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection14">b1L-SRA600</a> <a href="79165?version=1&table=Limitoncrosssection15">b1L-SRA750</a> <a href="79165?version=1&table=Limitoncrosssection16">b1L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection17">best combination</a> <a href="79165?version=1&table=Limitoncrosssection18">A-LowMass</a> <a href="79165?version=1&table=Limitoncrosssection19">A-HighMass</a> <a href="79165?version=1&table=Limitoncrosssection20">B combination</a><br/><br/><b>Cutflow:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=CutflowTable1">b0L-SRA (1 TeV, 1 GeV)</a> <a href="79165?version=1&table=CutflowTable2">b0L-SRB (700 GeV, 450 GeV)</a> <a href="79165?version=1&table=CutflowTable3">b0L-SRC (450 GeV, 430 GeV)</a><br/><i>mixed:</i> <a href="79165?version=1&table=CutflowTable4">b1L-SRA (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable5">b1L-SRA300-2j (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable6">b0L-SRA (700 GeV, 300 GeV)</a><br/><br/><b>Truth Code</b> and <b>SLHA Files</b> for the cutflows are available under "Resources" (purple button on the left)

- - - - - - - - - - - - - - - - - - - - <br/><b>Acceptance:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Acceptance1">b0L-SRA350</a> <a href="79165?version=1&table=Acceptance2">b0L-SRA450</a> <a href="79165?version=1&table=Acceptance3">b0L-SRA550</a> <a href="79165?version=1&table=Acceptance4">b0L-SRB</a> <a href="79165?version=1&table=Acceptance5">b0L-SRC</a> <a href="79165?version=1&table=Acceptance6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Acceptance7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Acceptance8">b1L-SRA450</a> <a href="79165?version=1&table=Acceptance9">b1L-SRA600</a> <a href="79165?version=1&table=Acceptance10">b1L-SRA750</a> <a href="79165?version=1&table=Acceptance11">b1L-SRB</a> <a href="79165?version=1&table=Acceptance12">b1L-best</a><br/><br/><b>Efficiency:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Efficiency1">b0L-SRA350</a> <a href="79165?version=1&table=Efficiency2">b0L-SRA450</a> <a href="79165?version=1&table=Efficiency3">b0L-SRA550</a> <a href="79165?version=1&table=Efficiency4">b0L-SRB</a> <a href="79165?version=1&table=Efficiency5">b0L-SRC</a> <a href="79165?version=1&table=Efficiency6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Efficiency7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Efficiency8">b1L-SRA450</a> <a href="79165?version=1&table=Efficiency9">b1L-SRA600</a> <a href="79165?version=1&table=Efficiency10">b1L-SRA750</a> <a href="79165?version=1&table=Efficiency11">b1L-SRB</a> <a href="79165?version=1&table=Efficiency12">b1L-best</a><br/><br/><b>Best SR Mapping:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=BestSR4">b0L</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=BestSR1">b1L</a> <a href="79165?version=1&table=BestSR2">b0L</a> <a href="79165?version=1&table=BestSR3">combined</a><br/><br/><b>Exclusion Contour:</b><br/><i>symmetric:</i> b0L-SRA350&nbsp;<a href="79165?version=1&table=Contour1">exp</a>&nbsp;<a href="79165?version=1&table=Contour2">obs</a> b0L-SRA450&nbsp;<a href="79165?version=1&table=Contour5">exp</a>&nbsp;<a href="79165?version=1&table=Contour6">obs</a> b0L-SRA550&nbsp;<a href="79165?version=1&table=Contour9">exp</a>&nbsp;<a href="79165?version=1&table=Contour10">obs</a> b0L-SRB&nbsp;<a href="79165?version=1&table=Contour11">exp</a>&nbsp;<a href="79165?version=1&table=Contour12">obs</a> b0L-SRC&nbsp;<a href="79165?version=1&table=Contour15">exp</a>&nbsp;<a href="79165?version=1&table=Contour16">obs</a> b0L-best&nbsp;<a href="79165?version=1&table=Contour17">exp</a>&nbsp;<a href="79165?version=1&table=Contour18">obs</a><br/><i>asymmetric:</i> b0L-SRA350&nbsp;<a href="79165?version=1&table=Contour3">exp</a>&nbsp;<a href="79165?version=1&table=Contour4">obs</a> b0L-SRA450&nbsp;<a href="79165?version=1&table=Contour7">exp</a>&nbsp;<a href="79165?version=1&table=Contour8">obs</a> b0L-SRB&nbsp;<a href="79165?version=1&table=Contour13">exp</a>&nbsp;<a href="79165?version=1&table=Contour14">obs</a> b0L-best&nbsp;<a href="79165?version=1&table=Contour19">exp</a>&nbsp;<a href="79165?version=1&table=Contour20">obs</a> b1L-SRA300-2j&nbsp;<a href="79165?version=1&table=Contour21">exp</a>&nbsp;<a href="79165?version=1&table=Contour22">obs</a> b1L-SRA450&nbsp;<a href="79165?version=1&table=Contour23">exp</a>&nbsp;<a href="79165?version=1&table=Contour24">obs</a> b1L-SRA600&nbsp;<a href="79165?version=1&table=Contour25">exp</a>&nbsp;<a href="79165?version=1&table=Contour26">obs</a> b1L-SRA750&nbsp;<a href="79165?version=1&table=Contour27">exp</a>&nbsp;<a href="79165?version=1&table=Contour28">obs</a> b1L-SRB&nbsp;<a href="79165?version=1&table=Contour29">exp</a>&nbsp;<a href="79165?version=1&table=Contour30">obs</a> b1L-best&nbsp;<a href="79165?version=1&table=Contour31">exp</a>&nbsp;<a href="79165?version=1&table=Contour32">obs</a> A-LowMass&nbsp;<a href="79165?version=1&table=Contour33">exp</a>&nbsp;<a href="79165?version=1&table=Contour34">obs</a> A-HighMass&nbsp;<a href="79165?version=1&table=Contour35">exp</a>&nbsp;<a href="79165?version=1&table=Contour36">obs</a> B combination&nbsp;<a href="79165?version=1&table=Contour37">exp</a>&nbsp;<a href="79165?version=1&table=Contour38">obs</a> Best combination&nbsp;<a href="79165?version=1&table=Contour39">exp</a>&nbsp;<a href="79165?version=1&table=Contour40">obs</a><br/><br/><b>SR Distribution:</b><br/><a href="79165?version=1&table=SRdistribution1">b0L-SRA</a>: $m_{\mathrm{CT}}$ <a href="79165?version=1&table=SRdistribution2">b0L-SRB</a>: $\mathrm{min[m_{T}(jet_{1-4}, E_{T}^{miss})]}$ <a href="79165?version=1&table=SRdistribution3">b0L-SRC</a>: ${\cal A}$ <a href="79165?version=1&table=SRdistribution4">b1L-SRA300-2j</a>: $\mathrm{m_{bb}}$ <a href="79165?version=1&table=SRdistribution5">b1L-SRA</a>: $\mathrm{m_{eff}}$ <a href="79165?version=1&table=SRdistribution6">b1L-SRB</a>: $\mathrm{m_{T}}$<br/><br/><b>Cross section upper limit:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Limitoncrosssection1">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection2">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection3">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection4">b0L-SRA550</a> <a href="79165?version=1&table=Limitoncrosssection5">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection6">b0L-SRC</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Limitoncrosssection7">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection8">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection9">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection10">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection11">b1L-best</a> <a href="79165?version=1&table=Limitoncrosssection12">b1L-SRA300-2j</a> <a href="79165?version=1&table=Limitoncrosssection13">b1L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection14">b1L-SRA600</a> <a href="79165?version=1&table=Limitoncrosssection15">b1L-SRA750</a> <a href="79165?version=1&table=Limitoncrosssection16">b1L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection17">best combination</a> <a href="79165?version=1&table=Limitoncrosssection18">A-LowMass</a> <a href="79165?version=1&table=Limitoncrosssection19">A-HighMass</a> <a href="79165?version=1&table=Limitoncrosssection20">B combination</a><br/><br/><b>Cutflow:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=CutflowTable1">b0L-SRA (1 TeV, 1 GeV)</a> <a href="79165?version=1&table=CutflowTable2">b0L-SRB (700 GeV, 450 GeV)</a> <a href="79165?version=1&table=CutflowTable3">b0L-SRC (450 GeV, 430 GeV)</a><br/><i>mixed:</i> <a href="79165?version=1&table=CutflowTable4">b1L-SRA (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable5">b1L-SRA300-2j (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable6">b0L-SRA (700 GeV, 300 GeV)</a><br/><br/><b>Truth Code</b> and <b>SLHA Files</b> for the cutflows are available under "Resources" (purple button on the left)

Signal acceptance (in %) in the ( M(SBOTTOM), M(NEUTRALINO) ) mass plane for the symmetric decay of the sbottom into bottom quark and neutralino, for the b0L-SRA350 signal region.

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Search for pair-produced third-generation squarks decaying via charm quarks or in compressed supersymmetric scenarios in $pp$ collisions at $\sqrt{s}=8~$TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 90 (2014) 052008, 2014.
Inspire Record 1304459 DOI 10.17182/hepdata.65457

Results of a search for supersymmetry via direct production of third-generation squarks are reported, using $20.3$ fb$^{-1}$ of proton-proton collision data at $\sqrt{s} = 8$ TeV recorded by the ATLAS experiment at the LHC in 2012. Two different analysis strategies based on monojet-like and $c$-tagged event selections are carried out to optimize the sensitivity for direct top squark pair production in the decay channel to a charm quark and the lightest neutralino ($\tilde{t}_1 \to c + \tilde{\chi}_{1}^{0}$) across the top squark--neutralino mass parameter space. No excess above the Standard Model background expectation is observed. The results are interpreted in the context of direct pair production of top squarks and presented in terms of exclusion limits in the ($m_{\tilde{t}_1}$, $m_{\tilde{\chi}_{1}^{0}}$) parameter space. A top squark of mass up to about 240 GeV is excluded at 95$\%$ confidence level for arbitrary neutralino masses, within the kinematic boundaries. Top squark masses up to 270 GeV are excluded for a neutralino mass of 200 GeV. In a scenario where the top squark and the lightest neutralino are nearly degenerate in mass, top squark masses up to 260 GeV are excluded. The results from the monojet-like analysis are also interpreted in terms of compressed scenarios for top squark pair production in the decay channel $\tilde{t}_1 \to b + ff^{'} + \tilde{\chi}^{0}_{1}$ and sbottom pair production with $\tilde{b}_1 \to b + \tilde{\chi}^{0}_{1}$, leading to a similar exclusion for nearly mass-degenerate third-generation squarks and the lightest neutralino. The results in this paper significantly extend previous results at colliders.

57 data tables

Distribution of the discriminator against b-jets, log(Pcharm/Pb), for the first-leading jet. For illustration purposes, the distributions of two different SUSY scenarios for stop pair production with the decay mode $\tilde{t}_1 \rightarrow c + \tilde{\chi}^{0}_1$ are included. In the SUSY signal, the first-leading jet mostly originates from ISR.

Distribution of the discriminator against b-jets, log(Pcharm/Pu), for the third-leading jet. For illustration purposes, the distributions of two different SUSY scenarios for stop pair production with the decay mode $\tilde{t}_1 \rightarrow c + \tilde{\chi}^{0}_1$ are included. In the SUSY signal, the third-leading jet is expected to contain a large fraction of c-jets.

The measured $E_T^{miss}$ distribution in the $W \rightarrow \mu \nu$ control region, for the M1 selection, compared to the background predictions. The latter include the global normalization factors extracted from the fit.

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Search for strong production of supersymmetric particles in final states with missing transverse momentum and at least three $b$-jets at $\sqrt{s}$= 8 TeV proton-proton collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 10 (2014) 024, 2014.
Inspire Record 1304457 DOI 10.17182/hepdata.65323

This paper reports the results of a search for strong production of supersymmetric particles in 20.1 fb$^{-1}$ of proton-proton collisions at a centre-of-mass energy of 8 TeV using the ATLAS detector at the LHC. The search is performed separately in events with either zero or at least one high $p_\mathrm{T}$ lepton (electron or muon), large missing transverse momentum, high jet multiplicity and at least three jets identified as originated from the fragmentation of a b-quark. No excess is observed with respect to the Standard Model predictions. The results are interpreted in the context of several supersymmetric models involving gluinos and scalar top and bottom quarks, as well as a mSUGRA/CMSSM model. Gluino masses up to 1340 GeV are excluded, depending on the model, significantly extending the previous ATLAS limits.

49 data tables
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