Search for Production of Heavy Particles Decaying to Top Quarks and Invisible Particles in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV

Abstract

We present a search for a new particle $T^{\prime }$ decaying to top quark via $T^{\prime }\to t+X$, where $X$ is an invisible particle. In a data sample with 4.8 fb${}^{-1}$ of integrated luminosity collected by the CDF II detector at Fermilab in $p\bar{p}$ collisions with $\sqrt{s}=1.96$ TeV, we search for pair production of $T^{\prime }$ in the lepton+jets channel, $p\bar{p}\to t\bar{t}+X+X\to \ell \nu bq{q}^{\prime }b+X+X$. We interpret our results primarily in terms of a model where $T^{\prime }$ are exotic fourth generation quarks and $X$ are dark matter particles. Current direct and indirect bounds on such exotic quarks restrict their masses to be between 300 and 600 GeV$/c^2$, the dark matter particle mass being anywhere below $m_{T^{\prime }}$. The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of $T^{\prime }\overline{T^{\prime }}\to t\bar{t}+X+X$. We apply these limits to the dark matter model and exclude the fourth generation exotic quarks $T^{\prime }$ at 95% confidence level up to $m_{T^{\prime }}=360$ GeV$/c^2$ for $m_X\le 100$ GeV$/c^2$.

References in corpus (18)

• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• A Unified Approach to the Classical Statistical Analysis of Small Signals
• ALPGEN, a generator for hard multiparton processes in hadronic collisions
• Dark Matter Candidates from Particle Physics and Methods of Detection
• MadGraph/MadEvent v4: The New Web Generation
• An update on vector boson pair production at hadron colliders
• Measurement of the J/Psi Meson and b-Hadron Production Cross Sections in ppbar Collisions at sqrt s = 1960 GeV
• NLL resummation of the heavy-quark hadroproduction cross-section
• Little Hierarchy, Little Higgses, and a Little Symmetry
• Determination of the Jet Energy Scale at the Collider Detector at Fermilab
• The t-tbar cross-section at 1.8 and 1.96 TeV: a study of the systematics due to parton densities and scale dependence
• Baryon and Lepton Number as Local Gauge Symmetries
• Top Quark Mass Measurement Using the Template Method in the Lepton + Jets Channel at CDF II
• First Measurements of Inclusive W and Z Cross Sections from Run II of the Tevatron Collider
• Measurement of the ttbar Production Cross Section in ppbar collisions at sqrt{s} = 1.96 TeV using Lepton+Jets Events with Jet Probability b-tagging
• Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt(s) = 1.96 TeV
• Dark Matter-Motivated Searches for Exotic 4th Generation Quarks in Tevatron and Early LHC Data
• The ${\alpha }_S$ Dependence of Parton Distributions

Cited by in corpus (25)

• SUSY, the Third Generation and the LHC
• Probing natural SUSY from stop pair production at the LHC
• Search for single production of a vector-like T quark decaying to a Z boson and a top quark in proton-proton collisions at $\sqrt{s}=$13 TeV
• Stops and MET: the shape of things to come
• Vector-like Singlet Quarks: a Roadmap
• Top-flavored dark matter and the forward-backward asymmetry
• Search for New Phenomena in ttbar Events with Large Missing Transverse Momentum in Proton-Proton Collisions at sqrt(s) = 7 TeV with the ATLAS Detector
• Search for long-lived particles decaying to jet pairs
• Probing Light Stop Pairs at the LHC
• Search for flavour-changing neutral current top-quark decays to $qZ$ in $pp$ collision data collected with the ATLAS detector at $\sqrt{s}=8$ TeV
• Phenomenology of 2HDM with VLQs
• Top-Quark Physics: Status and Prospects
• Search for New $T^{\prime }$ Particles in Final States with Large Jet Multiplicities and Missing Transverse Energy in ppbar Collisions at sqrt(s) = 1.96 TeV
• Scalar versus fermionic top partner interpretations of $t\bar{t}+E_T^{\mathrm{miss}}$ searches at the LHC
• Search for a dark matter candidate produced in association with a single top quark in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV
• Hitting sbottom in natural SUSY
• Proton stability from a fourth family
• K_1(1270)-K_1(1400) mixing and the fourth generation SM effects in B-->K_1l^+l^- decays
• LHC signatures of vector-like quarks
• B's with Direct Decays: Tevatron and LHC Discovery Prospects in the b\bar{b}+MET Channel
• New Physics from the Top at the LHC
• Large Jet Multiplicities and New Physics at the LHC
• Top Quark Physics at the Tevatron
• The 750 GeV threshold to a new particle world
• Phenomenology of extra quarks at the LHC