相关论文: Boosted Semileptonic Tops in Stop Decays
The top quark may hold the key to new physics associated with the electroweak symmetry-breaking sector, given its large mass and enhanced coupling to the Higgs sector. We systematically categorize generic interactions of a new particle that…
So far the squarks have not been detected at the LHC indicating that they are heavier than a few hundred GeVs, if they exist. The lighter stop can be considerably lighter than the other squarks. We study the possibility that a…
An overview of tools and methods for the reconstruction of high-boost top quark decays at the LHC is given in this report. The focus is on hadronic decays, in particular an overview of the current status of top quark taggers in physics…
In scenarios that stabilize the electroweak scale, the top quark is typically accompanied by partner particles. In this work, we demonstrate how extended stabilizing symmetries can yield scalar or fermionic top partners that transform as…
A search for supersymmetry through the direct pair production of top squarks, with Higgs (H) or Z bosons in the decay chain, is performed using a data sample of proton-proton collisions at sqrt(s) = 8 TeV collected in 2012 with the CMS…
This paper describes a method for detecting a rare top quark decay into a charm quark and a Higgs boson (H), which decays further into b quarks, at the Large Hadron Collider (LHC), and introduces a tagging algorithm to identify boosted tops…
Current searches for the light top squark (stop) mostly focus on the decay channels of $\tilde{t} \rightarrow t \chi_1^0$ or $\tilde{t} \rightarrow b \chi_1^\pm \rightarrow bW \chi_1^0$, leading to $t\bar{t}/bbWW+\met$ final states for stop…
The precise reconstruction of the mass peak of long-lived heavy neutral leptons (HNLs) helps to improve the sensitivity for sterile neutrino searches in both fixed-target and collider environments (e.g., SHiP and the LHC). We present an…
An overview of the boosted top production analyses using data collected by the ATLAS and CMS experiments at $\sqrt{s}=$ 8 TeV and 13 TeV of proton-proton collisions at the LHC is presented. These analyses use techniques for the…
Composite Higgs models provide a natural, non-supersymmetric solution to the hierarchy problem. In these models, one or more sets of heavy top-partners are typically introduced. Some of these new quarks can be relatively light, with a mass…
Observables sensitive to top quark polarization are important for characterizing or even discovering new physics. The most powerful spin analyzer in top decay is the down-type fermion from the W, which in the case of leptonic decay allows…
We study the top quark pair events production in $pp$ collisions in the $\ell$+jets channel at the LHC energy of $\sqrt{s} = 14$ TeV for Standard Model as well as new physics processes. We explore the usage of semi-boosted topologies where…
Fermionic third generation top partners are generic in composite Higgs models. They are likely to decay into third generation quarks and electroweak bosons. We propose a novel cut-and-count-style analysis in which we cross correlate the…
This dissertation addresses the question of how to detect light top squarks at the upgraded Fermilab Tevatron collider. After a brief introduction to supersymmetry, the basic phenomenology of the light stop is reviewed and the current…
The LHC discovery potential of heavy top partners decaying into a top quark and a $Z$ boson is studied in the trilepton channel at 13 TeV in the single production mode. The clean multilepton final state allows to strongly reduce the…
Searching for top squark (stop) is a crucial task of the LHC. When the flavor conserving two body decays of the stop are kinematically forbidden, the stops produced near the threshold will live long enough to form bound states which…
The LHC discovery potential of heavy top partners decaying into a top quark and a $Z$ boson is studied in the trilepton channel at $\sqrt{s}=13$ TeV. The clean multilepton final state allows to strongly reduce the background contaminations…
In composite Higgs models (CHMs), electroweak precision data generically push colourless composite vector resonances to a regime where they dominantly decay into pairs of light top partners. This greatly attenuates their traces in canonical…
The search for new physics in top quark decays at the LHC is reviewed in this paper. Results from ATLAS and CMS experiments on top quark decays within the Standard Model are presented together with the measurements of the W boson…
We propose a new search strategy for directly-produced sbottoms at the LHC with a small mass splitting between the sbottom and its decayed stable neutralino. Our search strategy is based on boosting sbottoms through an energetic initial…