Search for pair-produced scalar and vector leptoquarks decaying into third-generation quarks and first- or second-generation leptons in pp collisions with the ATLAS detector
A search for pair-produced scalar and vector leptoquarks decaying into quarks and leptons of different generations is presented. It uses the full LHC Run 2 (2015-2018) data set of 139 fb$^{-1}$ collected with the ATLAS detector in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 13$ TeV. Scalar leptoquarks with charge -(1/3)e as well as scalar and vector leptoquarks with charge +(2/3)e are considered. All possible decays of the pair-produced leptoquarks into quarks of the third generation (t, b) and charged or neutral leptons of the first or second generation ($e, μ, ν$) with exactly one electron or muon in the final state are investigated. No significant deviations from the Standard Model expectation are observed. Upper limits on the production cross-section are provided for eight models as a function of the leptoquark mass and the branching ratio of the leptoquark into the charged or neutral lepton. In addition, lower limits on the leptoquark masses are derived for all models across a range of branching ratios. Two of these models have the goal of providing an explanation for the recent B-anomalies. In both models, a vector leptoquark decays into charged and neutral leptons of the second generation with a similar branching fraction. Lower limits of 1980 GeV and 1710 GeV are set on the leptoquark mass for these two models.
Search for 1st-Generation Leptoquarks Using the ATLAS Detector
本文报道了在LHC记录的7 TeV ATLAS数据的1/fb中寻找标量细夸克对产生的结果。轻夸克是一种假设的三重色玻色子，它同时带有夸克和轻子的味道，因此衰变为夸克和轻子，与任何标准模型粒子不同。轻夸克产生于许多超越标准模型的理论。在这个分析中检查的通道需要至少一个轻夸克衰变到电子，其中包括最终状态eejj和evjj。没有多余的事件被观察到，从而限制允许leptoquark质量被确定。我们在95%的置信水平上排除了质量m < 660（607）GeV的第一代标量细夸克的产生，假设细夸克衰变到电子的分支分数为1.0（0.5）。
ATLAS Sensitivity to Leptoquarks, W_R and Heavy Majorana Neutrinos in Final States with High-pt Dileptons and Jets with Early LHC Data at 14 TeV proton-proton collisions
Search for a singly produced third-generation scalar leptoquark decaying to a $τ$ lepton and a bottom quark in proton-proton collisions at $\sqrt{s} =$ 13 TeV
Searches for third-generation scalar leptoquarks in $\sqrt{s}$ = 13 TeV pp collisions with the ATLAS detector
对标量轻夸克的对产生进行了限制，考虑了轻夸克衰变为第三代夸克（$t$，$b$）和轻子（$τ$，$ν$）的所有可能.对于上型（$\mathrm{LQ}_{3}^{u}$ $\rightarrow t ν/ b τ$）和下型（$\mathrm{LQ}_{3}^{d}$ $\rightarrow b ν/ t τ$）细夸克，极限是细夸克质量和带电轻子分支比的函数。许多结果是对以前发表的ATLAS检索的重新解释。在所有情况下，使用ATLAS探测器在2015年和2016年记录的质量中心能量为$\sqrt{s}$ = 13 TeV的LHC质子-质子碰撞数据，对应于36.1 fb $^{-1}$的积分光度。对于$\mathrm{LQ}_{3}^{u}$和$\mathrm{LQ}_{3}^{d}$两者，与分支比无关地排除低于800 GeV的质量，对于分支比等于零或1的极限情况，排除低于约1 TeV的质量。
Search for pair production of scalar leptoquarks decaying into first- or second-generation leptons and top quarks in proton-proton collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
Search for a leptoquark in events with a hadronically decaying $τ$-lepton and missing transverse momentum using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)（欧洲核子研究中心（CERN））
Search for pair production of third-generation scalar leptoquarks decaying into a top quark and a $τ$-lepton in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
Searches for scalar leptoquarks and differential cross-section measurements in dilepton-dijet events in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV with the ATLAS experiment
Search for heavy neutrinos or third-generation leptoquarks in final states with two hadronically decaying tau leptons and two jets in proton-proton collisions at sqrt(s) = 13 TeV
Search for excited $τ$-leptons and leptoquarks in the final state with $τ$-leptons and jets in pp collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
Search for leptoquark pair production decaying into $te^- \bar{t}e^+$ or $tμ^- \bar{t}μ^+$ in multi-lepton final states in $pp$ collisions at 13 TeV with the ATLAS detector
Search for resonant leptoquark production via lepton-jet signatures in $pp$ collisions at $\sqrt{s} = 13$ TeV and $\sqrt{s} = 13.6$ TeV with the ATLAS detector
EUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)（欧洲核子研究中心（CERN））
本文利用 ATLAS 装置在 13 和 13.6 TeV 激撞数据中，通过轻子-喷注信号搜索共振轻子淬克产生，排除了标量轻子淬克的高质量范围。
Search for a scalar partner of the top quark in the all-hadronic $t\bar{t}$ plus missing transverse momentum final state at $\sqrt{s}=13$ TeV with the ATLAS detector
Search for pair-production of vector-like quarks in final states with at least one $Z$ boson decaying into a pair of electrons or muons in $pp$ collision data collected with the ATLAS detector at $\sqrt{s}$ = 13 TeV
Search for heavy resonances decaying into a photon and a hadronically decaying Higgs boson in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
Search for heavy resonances decaying to a photon and a hadronically decaying $Z/W/H$ boson in $pp$ collisions at $\sqrt{s}=13$ $\mathrm{TeV}$ with the ATLAS detector
Search for down-type fourth generation quarks with the ATLAS detector in events with one lepton and hadronically decaying W bosons
这封信介绍了在轻子+喷流通道中通过b '->Wt衰变的重下型夸克的成对产生的研究，如b' b '->WtWt->bbWWWW->lvbbqqqqqq。除了需要恰好一个轻子、大的缺失横向动量和至少六个喷注之外，附近喷注对的不变质量被用来识别高横向动量的W玻色子。在ATLAS探测器记录的sqrt（s）= 7 TeV pp碰撞的积分亮度为1.04 fb^-1的数据中，在95%的置信水平下排除了质量小于480 GeV的重降型夸克。
Search for dark matter in events with missing transverse momentum and a Higgs boson decaying into two photons in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector
